Specific Recognition of Breast Cancer Cells In Vitro Using Near Infrared-Emitting Long-Persistence Luminescent Zn_3Ga_2Ge_2O_(10):Cr^(3+)Nanoprobes

In this paper, near-infrared emitting long-persistence luminescent Zn3Ga2Ge2O10:Cr3?(ZGG) nanoparticles with diameters of 30–100 nm and bright luminescence were prepared by a sol–gel synthesis method. After the surface amination, the nanoparticles were further bioconjugated with breast cancer-specific monoclonal antibody(anti-Ep CAM) to form ZGG-Ep CAM nanoprobes which can specifically target breast cancer cell lines(MCF7) in vitro. The results of in vitro images show that the luminescence signals from the cells treated with ZGG-Ep CAM nanoprobes are stronger than those from cells treated with ZGG-unconjugated antibody, indicating that the prepared ZGG-Ep CAM nanoprobes possessed excellent specific recognition capability. Furthermore, due to their long afterglow properties, the imaging could persist more than 1 h. Therefore, these nanoprobes could not only provide a high specificity detection method for cancer cells but also realize the long-time monitoring. Developed near-infrared emitting long-persistence luminescent nanoprobes will be expected to find new perspectives for cell therapy research and diagnosis applications.

Entropy-based multipath detection model for MIMO radar

An optimized detection model based on weighted entropy for multiple input multiple output (MIMO) radar in multipath environment is presented. After defining the multipath distance difference (MDD), the multipath received signal model with four paths is built systematically. Both the variance and correlation coefficient of multipath scattering coefficient with MDD are analyzed, which indicates that the multipath variable can decrease the detection performance by reducing the echo power. By making use of the likelihood ratio test (LRT), a new method based on weighted entropy is introduced to use the positive multipath echo power and suppress the negative echo power, which results in better performance. Simulation results show that, compared with non-multipath environment or other recently developed methods, the proposed method can achieve detection performance improvement with the increase of sensors.

Tensor-Based Source Localization Method with EVS Array

In many wireless scenarios,e.g.,wireless communications,radars,remote sensing,direc-tion-of-arrival(DOA)is of great significance.In this paper,by making use of electromagnetic vec-tor sensors(EVS)array,we settle the issue of two-dimensional(2D)DOA,and propose a covari-ance tensor-based estimator.First of all,a fourth-order covariance tensor is used to formulate the array covariance measurement.Then an enhanced signal subspace is obtained by utilizing the high-er-order singular value decomposition(HOSVD).Afterwards,by exploiting the rotation invariant property of the uniform array,we can acquire the elevation angles.Subsequently,we can take ad-vantage of vector cross-product technique to estimate the azimuth angles.Finally,the polarization parameters estimation can be easily completed via least squares,which may make contributions to identifying polarization state of the weak signal.Our tensor covariance algorithm can be adapted to spatially colored noise scenes,suggesting that it is more flexible than the most advanced algorithms.Numerical experiments can prove the superiority and effectiveness of the proposed approach.

X-ray excited Mn^(2+)-doped persistent luminescence materials with biological window emission for in vivo bioimaging

In recent years,persistent luminescence materials(PLMs)excited by X-rays and emitting in biological windows have received extensive attention in the field of high-sensitivity bioimaging.Transition metal Mn^(2+)is an ideal emission center,but few studies focus on Mn^(2+)-doped PLMs with X-ray excitation and biological window emission.Here,we report a Mn^(2+)-doped PLM,LiYGeO_(4):Mn^(2+)(LYGM),with excellent biological window persistent luminescence emission.After excitation by UV,LYGM produces a durable biological window of persistent luminescence emission at 660 nm for up to 20 h.More importantly.LYGM can be repeatedly excited by X-rays,resulting in long-term biological window persistent luminescence emission.In addition,we obtain LYGM around 200 nm in diameter by ball milling and centrifugation and improve its biocompatibility by surface modification to apply it to in vivo imaging in mice.After LYGM are injected into mice through the tail vein,in situ excitation of X-rays can be achieved.After the persistent luminescence decays,LYGM can be re-excited for repeated imaging.Therefore,LYGM shows potential prospects for in vivo deep tissue and long-term bioimaging.

X-ray-activated Bi^(3+)/Pr^(3+)co-doped LiYGeO_4 phosphor with UV and NIR dual-emissive persistent luminescence

X-ray-activated luminescence materials have broad application prospects in photodynamic therapy of deep tissue.Among them,X-ray-activated persistent luminescence materials(PLMs)exhibiting multiple emission peaks have drawn extensive attention for the ir capacity to achieve a combination of bioimaging and therapeutic functions.Here,we developed a novel PLM,LiYGeO_4:Bi^(3+),Pr^(3+),that simultaneously exhibits UV and NIR dual persistent luminescence(PersL)emissions after irradiation by X-ray.The material can be re peatedly excited by X-ray and emits similar lumine scence intensity every time,which shows good PersL stability.In addition,LiYGeO_4:Bi^(3+),Pr^(3+)exhibits photostimulated PersL properties by stimulation with a red light-emitting diode(LED)or NIR laser after long-term decay.This work provides a new choice of X-ray-excited PLMs with UV and NIR dual emission and the novel phosphor shows promise as a potential candidate for the integration of treatment and diagnosis of deep tumors.

Plant pan-genomics and its applications

Plant genomes are so highly diverse that a substantial proportion of genomic sequences are not shared among individuals.The variable DNA sequences,along with the conserved core sequences,compose the more sophisticated pan-genome that represents the collection of all non-redundant DNA in a species.With rapid progress in genome sequencing technologies,pan-genome research in plants is now accelerating.Here we review recent advances in plant pan-genomics,including major driving forces of structural variations that constitute the variable sequences,methodological innovations for representing the pan-genome,and major successes in constructing plant pan-genomes.We also summarize recent efforts toward decoding the remaining dark matter in telomere-to-telomere or gapless plant genomes.These new genome resources,which have remarkable advantages over numerous previously assembled less-than-perfect genomes,are expected to become new references for genetic studies and plant breeding.

具有红色上转换发光和近红外二区发光的生物可降解镧系掺杂无机纳米颗粒用于生物成像和光动力治疗

近红外二区镧掺杂无机纳米颗粒由于其较低的光子散射和较弱的自身荧光特性而受到广泛关注.然而,这些纳米颗粒具有“刚性”和生理惰性的晶格结构(例如NaYF_(4):Yb,Er),无法在体内降解,限制了它们在生物医学上的进一步应用.改变化学结构,实现晶体由“刚性”向“软性”的转变,是一种促进其可降解生物应用的可行方法.在这里,我们报道了一种可生物降解的近红外二区镧掺杂无机纳米颗粒Na_(3)ZrF_(7):Yb,Er,Ce(NZF).通过Na的调控和Ce^(3+)的掺杂优化,NZF纳米粒子的近红外二区下转换发光强度比Na_(3)ZrF_(7):Yb,Er提高了约37倍.由于其“软”的晶格特征,水可以破坏其晶体结构,降解产物可以从器官和组织中排出.此外,NZF还表现出红色的上转换发光能力.在表面改性后,我们基于其近红外二区的下转换发光和红色上转换发光的特性进行了可降解生物成像应用和光动力治疗的概念验证,这些发现将有利于稀土掺杂无机纳米颗粒的未来生物医学应用.

基于低管秩张量分解的互质阵列自适应波束成形算法

互质阵列因其大阵列孔径和高自由度特性在波束成形领域受到广泛关注.为了充分利用该特性,近年来学者们提出了基于孔洞填充的算法,有效提高了互质阵列波束成形的性能.然而,这些算法存在计算量大、噪声鲁棒性弱等缺点,难以适应复杂多变的实际环境.为此,本文利用张量的多维结构在参数估计上的性能优势,提出了一种基于低管秩张量分解的互质阵列自适应波束成形算法.首先将互质阵列的多采样虚拟信号矩阵重排为张量形式,利用其低管秩特性补全缺失的互相关信息;然后从补全后的张量数据中提取信号参数,并与目标先验进行匹配,最终得到波束成形权矢量.本算法分别利用ADMM和Tucker分解提高了张量补全和分解的运算效率;所设计的目标匹配方案也有效控制了算法误差.仿真结果展示了本算法在性能和计算复杂度相对于现有方法的优势,尤其是在低信噪比和少采样数的情况下.

A high-quality,phased genome assembly of broomcorn millet reveals the features of its subgenome evolution and 3D chromatin organization

Dear Editor,Grasses of the genus Panicumgrowin natural and agricultural ecosystems worldwide and include about 450 species distributed throughout tropical and temperate regions.Most Panicumgrasses remain unexploited,with the exceptions of broomcorn millet(P.miliaceum)(Shi et al.,2019;Zou et al.,2019),switchgrass(P.virgatum)(Lovell et al.,2021),Hall’s panicgrass(P.hallii)(Lovell et al.,2018),and a few other species that have been successfully domesticated into staple,forage,and energy crops.Broomcorn millet(2n=4x=36)is probably one of the earliest domesticated grain crops,originating in North China around 10000 years ago.

稀疏阵列MIMO雷达参数估计研究进展

利用稀疏阵列多输入多输出(multi-input and multi-output,MIMO)雷达的虚拟孔径扩展特性开展参数估计研究具有重要的理论意义和应用前景.本文以稀疏阵列MIMO雷达设计和参数估计为导向,以提高估计精度和降低运算量为落脚点,从子空间类和压缩感知类算法的契合点出发,围绕阵列设计、波达方向估计、角度联合估计等方面,构建了系统的稀疏阵列MIMO雷达参数估计理论.最后,从阵列优化设计、混合目标参数估计、非理想因素抑制和分布式平台搭建等方面展望了稀疏阵列MIMO雷达的发展趋势.

Hybrid Particle Swarm Optimization Algorithm Based on Entropy Theory for Solving DAR Scheduling Problem

An efficient task-scheduling algorithm in the Digital Array Radar(DAR) is essential to ensure that it can handle a large number of requested tasks simultaneously. As a solution to this problem, in this paper, we propose an optimization model for scheduling DAR tasks using a hybrid approach. The optimization model considers the internal task structure and the DAR task-scheduling characteristic. The hybrid approach integrates a particle swarm optimization algorithm with a genetic algorithm and a heuristic task-interleaving algorithm. We introduce the chaos theory to optimize initialized particles and use entropy theory to indicate the diversity of particles and adaptively adjust the inertia weight, the crossover probability, and the mutation probability. Then, we improve both the efficiency and global exploration ability of the hybrid algorithm. In the framework of the swarm exploration algorithm, we include a heuristic task-interleaving scheduling algorithm, which not only utilizes the wait interval to transmit or receive subtasks, but also overlaps the receive intervals of different tasks. In a large-scale simulation,we demonstrate that the proposed algorithm is more robust and effective than existing algorithms.

Evolution and Domestication Footprints Uncovered from the Genomes of Coix

Coix lacryma-jobi,a plant species closely related to Zea and Sorghum,is an important food and medicinal crop in Asia.However,no reference genome of this species has been reported,and its exact phylogeny within the Andropogoneae remains unresolved.Here,we generated a high-quality genome assembly of coix comprising～1.73 Gb with 44485 predicted protein-coding genes.We found coix to be a typical diploid plant with an overall 1-to-1 syntenic relationship with the Sorghum genome,despite its drastic genome expansion(～2.3-fold)due mainly to the activity of transposable elements.Phylogenetic analysis revealed that coix diverged with sorghum～10.41 million years ago,which was～1.49 million years later than the divergence between sorghum and maize.Resequencing of 27 additional coix accessions revealed that they could be unambiguously separated into wild relatives and cultivars,and suggested that coix experienced a strong genetic bottleneck,resulting in the loss of about half of the genetic diversity during domestication,even though many traits have remained undomesticated.Our data not only provide novel comparative genomic and evolutionary insights into the Andropogoneae lineage,but also an important resource that will greatly benefit molecular breeding of this important crop.

Phase evolution, microstructure, electric properties of (Ba1–xBi0.67xNa0.33x)(Ti1–xBi0.33xSn0.67x)O3 ceramics

(Ba1–xBi0.67xNa0.33x)(Ti1–xBi0.33xSn0.67x)O3(abbreviated as BBNTBS,0.02≤x≤0.12)ceramics were fabricated via a traditional solid state reaction method.The phase transition of BBNTBS from tetragonal to pseudo cubic is demonstrated by XRD and Raman spectra.The BBNTBS(x=0.1)ceramics have decent properties with a highεr(~2250),smallΔε/ε25℃ values of±15%over a wide temperature range from–58 to 171℃,and low tanδ≤0.02 from 10 to 200℃.The basic mechanisms of conduction and relaxation processes in the high temperature region were thermal activation,and oxygen vacancies might be the ionic charge transport carriers.Meanwhile,BBNTBS(x=0.1)exhibited decent energy storage density(Jd=0.58 J/cm3)and excellent thermal stability(the variation of Jd is less than 3% in the temperature range of 25–120℃),which could be a potential candidate for high energy density capacitors.

Environmental fate and behavior of silver nanoparticles in natural estuarine systems

Silver nanoparticles(AgNPs) are widely used in many consumer products, whereas their environmental behaviors in natural aquatic systems remain unknown, especially in natural brackish media.Therefore, it is urgent to investigate the environmental fate of AgNPs in natural brackish waters.Here, we investigated the stability of citrate-coated AgNPs in natural brackish water collected from 6 different sites with distinct salinities in the Xinglinwan Reservoir, located in Xiamen City, southeast China.The obtained results showed that AgNP colloids remained stable in low-salinity waters, which was mainly determined by the effects of dissolved organic matter(DOM) promoting the stability of the nanoparticles.However, the environmental fate of AgNPs in high-salinity waters was dominated by the salinity or ionic strength, especially the free ion concentrations of Cl-, SO42-, or S2-, resulting in rapid sedimentation and dissolution.In addition, both DOM and salinity contributed to the environmental behavior of AgNPs in moderate-salinity waters,ultimately resulting in either colloidal stability or sedimentation.Overall, these results may reveal that AgNPs remain relatively stable for a long period in low-salinity natural waters,and that the stability might gradually decrease as AgNPs are transferred from freshwaters through brackish waters and eventually end up in seawater along the bay.Our findings also further indicate that the toxicity and potential risks of AgNPs may present more serious threats to the environment and organisms in natural freshwaters than in natural estuarine systems or seawater.

High energy storage density and power density achieved simultaneously in NaNbO_(3)-based lead-free ceramics via antiferroelectricity enhancement

High-performance lead-free dielectric ceramics with simultaneously high energy storage density and power density are in high demanded for pulse power systems.To realize excellent energy-storage characteristics,a strategy to enhance antiferroelectricity and construct a local random field simultaneously was proposed in this study.Based on the above strategy,a series of(1-x)NaNbO_(3)-xBi(Ni_(1/2)Sn_(1/2))O3[xBNS,x=0.05,0.10,0.15,0.20,and 0.22]solid solutions were designed and fabricated.An ultrahigh energy storage density(Utotal)of 7.35 J/cm^(3),and recoverable energy density(Urec)of 5.00 J/cm^(3) were achieved in the 0.10BNS ceramics.In addition,an adequate stability of energy storage properties at a range of temperatures(20e140℃),frequencies(1e100 Hz),and fatigue test durations(1e1-10^(4) cycles)were realized in 0.10BNS ceramics.0.10BNS ceramics displayed a high current density of 1005 A/cm2,an ultrahigh power density of 100.5 MW/cm^(3,)and an ultrashort discharge time of 46.5 ns?This remarkable performance not only justified our strategy but also confirmed 0.10BNS ceramics as a promising candidate for energy storage.

Cr^(3+)/Y^(3+)co-doped persistent luminescence nanoparticles with biological window activation for in vivo repeatable imaging

The near-infrared(NIR)persistent luminescence materials(PLMs)can remain long-lasting luminescence after removal of the excitation light,which permits bioimaging with high sensitivity owing to the absence of background fluorescence interference from in situ excitation.Recently,the NIR PLMs have aroused intensive research interest in bioimaging.However,the optimal excitation wavelength of current NIR PLMs is located in the ultraviolet region with shallow tissue penetration,making it difficult to activate effectively in vivo,and seriously hindering their further application in bioimaging.Herein,we report a novel kind of Cr^(3+)ions and Y^(3+)ions co-doped NIR PLM,Zn_(1.3)Ga_(1.4)Sn_(0.3)O_(4):Cr^(3+),Y^(3+)(ZGSCY),which emits NIR persistent luminescence at 696 nm.Compared with Zn_(1.3)Ga_(1.4)Sn_(0.3)O_(4):Cr^(3+)(ZGSC)excited by the light with a wavelength in the biological window(>650 nm),after being co-doped with Y^(3+)ions,the NIR persistent luminescence performance of ZGSCY is significantly improved because of the increase of trap concentration in the matrix.In addition,we synthesized ZGSCY nanoparticles(NPs)by the combustion method,which exhibit excellent optical properties after being excited by the light with a wavelength in the biological window.After surface modification with PEG,the ZGSCY NPs present low cytotoxicity.Notably,due to the co-doping of Y^(3+)ions,the signal-to-noise ratio(SNR)of ZGSCY NPs in vivo imaging is about 1.8 times higher than that of the ZGSC NPs.Furthermore,the rechargeable in vivo imaging and passive tumor-targeted imaging are successfully achieved by activating with a lightemitting diode(LED,659 nm)after intravenous injection of ZGSCY.Thus,this kind of NIR PLM with high excitation efficiency performance in the biological window is expected to promote its biomedical application in deep tissues.

Silica shell-assisted synthetic route for mono-disperse persistent nanophosphors with enhanced in vivo recharged near-infrared persistent luminescence

Near-infrared （NIR） persistent-luminescence nanoparticles have emerged as a new class of background-free contrast agents that are promising for in vivo imaging. The next key roadblock is to establish a robust and controllable method for synthesizing monodisperse nanoparticles with high luminescence brightness and long persistent duration. Herein, we report a synthesis strategy involving the coating/etching of the SiO2 shell to obtain a new class of small NIR highly persistent luminescent ZnGa2O4：Cr^3＋,Sn^4＋（ZGOCS） nanoparticles. The optimized ZGOCS nanoparticles have an excellent size distribution of -15 nm without any agglomeration and an NIR persistent luminescence that is enhanced by a factor of 13.5, owing to the key role of the SiO2 shell in preventing nanoparticle agglomeration after annealing. The ZGOCS nanoparticles have a signal-to-noise ratio -3 times higher than that of previously reported ZnGa204：Cr^3＋ （ZGC-1） nanoparticles as an NIR persistent-luminescence probe for in vivo bioimaging. Moreover, the persistent-luminescence signal from the ZGOCS nanoparticles can be repeatedly re-charged in situ with external excitation by a white light- emitting diode; thus, the nanopartides are suitable for long-term in vivo imaging applications. Our study suggests an improved strategy for fabricating novel high-performance optical nanoparticles with good biocompatibility.

A novel Gd-based phosphor NaGdGeO_(4):Bi^(3+),Li^(+)with super-long ultraviolet-A persistent luminescence

In very recent years,ultraviolet(UV)persistent luminescent materials(PLMs)have attracted widespread attention due to their potential biological applications.However,owing to the lack of suitable emitters and hosts,the design and development of excellent UV PLMs remain challenging.Here,we report a new Gd-based PLM NaGdGeO_(4):Bi^(3+)with super-long UVA persistent luminescence(PersL).By further codoping Li^(+)ions to increase the concentration of traps,the UVA PersL intensity of NaGdGeO_(4):Bi^(3+)is increased by 5.5 times.The optimal NaGdGeO_(4):Bi^(3+),Li^(+)exhibits excellent UVA PersL and can persist for more than 200 h.Moreover,the phosphor NaGdGeO_(4):Bi^(3+),Li^(+)also exhibits photostimulated property with a red LED or NIR laser excitation after the long-term decay,and can be activated by X-ray.This promising Gd-based UVA PLM is expected to have potential applications in biomedicine through triggering photocatalysts or photosensitizers by its UVA PersL to achieve photodynamic therapy and its potential ability of magnetic resonance(MR)imaging due to Gd^(3+)ions as MR imaging probe contained in the host NaGdGeO_(4).

Enhanced thermal and frequency stability and decent fatigue endurance in lead-free NaNbO_(3) -based ceramics with high energy storage density and efficiency

Lead-free ceramic capacitors have the application prospect in the dielectric pulse power system due to the advantages of large dielectric constant,lower dielectric loss and good temperature stability.Never-theless,most reported dielectric ceramics have limitation of realizing large energy storage density(W_(rec))and high energy storage efficiency(h)simultaneously due to the low breakdown electric field(E_(b)),low maximum polarization and large remanent polarization(P_(r)).These issues above can be settled by raising the bulk resistivity of dielectric ceramics and optimizing domain structure.Therefore,we designed a new system by doping(Bi_(0.5)Na_(0.5))_(0.7)Sr_(0.3)TiO_(3) into 0.9NaNbO_(3)-0.1Bi(Ni_(0.5)Zr_(0.5))O_(3) ceramics,which simulta-neously obtained a higher bulk resistivity by decreasing the grain size and achieved a smaller P_(r) by optimizing domain structure,thus the better E_(b) of 530 kV/cm and W_(rec) of 6.43 J/cm^(3) were achieved,h was improved from 34%to 82%.Besides,the 0.4BNST ceramics show excellent temperature,frequency and fatigue stability under the conditions of 20-180℃,1-100 Hz and 104 cycles,respectively.Mean-while,superior power density(P_(D)=107 MW/cm^(3)),large current density(C_(D)=1070 A/cm^(2))and discharge speed(1.025 m s)were achieved in 0.4BNST ceramic.Finally,the charge-discharge performance displayed good temperature stability in the temperature range of 30℃-180℃.The above results indicated that the ceramics have potential practical value in the field of energy storage capacitor.

HITAC-seq enables high-throughput cost-effective sequencing of plasmids and DNA fragments with identity

DNA sequencing is vital for many aspects of biological research and diagnostics. Despite the development of second and third generation sequencing technologies, Sanger sequencing has long been the only choice when required to precisely track each sequenced plasmids or DNA fragments. Here, we report a complete set of novel barcoding and assembling system, Highly-parallel Indexed Tagmentation-reads Assembled Consensus sequencing(HITAC-seq), that could massively sequence and track the identities of each individual sequencing sample. With the cost of much less than that of single read of Sanger sequencing,HITAC-seq can generate high-quality contiguous sequences of up to 10 kilobases or longer. The capability of HITAC-seq was confirmed through large-scale sequencing of thousands of plasmid clones and hundreds of amplicon fragments using approximately 100 pg of input DNAs. Due to its long synthetic length, HITACseq was effective in detecting relatively large structural variations, as demonstrated by the identification of a~1.3 kb Copia retrotransposon insertion in the upstream of a likely maize domestication gene. Besides being a practical alternative to traditional Sanger sequencing, HITAC-seq is suitable for many highthroughput sequencing and genotyping applications.