Grain-filling strategies of wheat of contrasting grain sizes under various planting patterns and irrigation levels

In a study comparing grain filling and yield in a large-and a small-grain-size wheat cultivar under two planting patterns and two irrigation regimes,plastic-covered ridge and furrow planting with sprinkler irrigation increased grain filling and yield in both cultivars.The largest contributors to grain yield were an extended active grain-filling period in Shuangda 1 and an increased mean grain-filling rate in XN538.

Arginine promotes seed energy metabolism,increasing wheat seed germination at low temperature

Low temperatures during germination inhibit seed growth,lead to small and weak seedlings,and significantly reduce the wheat yield.Alleviating the adverse effects of low temperature on wheat seed germination is highly important for achieving high and stable wheat yields.In this study,Tongmai 6(insensitive)and Zhengmai 113(sensitive),which have different low-temperature sensitivities during germination were treated with low temperature during germination.The transcriptome,metabolome and physiological data revealed that low temperature decreased the germination rate,downregulated the expression of a large number of genes involved in regulating glycometabolism,and inhibited carbon,nitrogen(especially amino acids)and energy metabolism in the seeds.Arginine content increased at low temperature,and its increase in the low-temperature-tolerant variety was significantly greater than that in the sensitive variety.Arginine priming experiment showed that treatment with an appropriate concentration of arginine improved the seed germination rate.The conversion of starch to soluble sugar significantly increased under exogenous arginine conditions,the content of key metabolites in energy metabolism increased,and the utilization of ATP in the seeds increased.Taken together,arginine priming increased seed germination at low temperature by relieving inhibition of seed carbon and nitrogen metabolism and improving seed energy metabolism.

Application of Secondary Logging Interpretation—Taking Yan 9 Reservoir in X Area as an Example

Logging data and its interpretation results are one of the most important basic data for understanding reservoirs and oilfield development. Standardized and unified logging interpretation results play a decisive role in fine reservoir description and reservoir development. Aiming at the problem of the conflict between the development effect and the initial interpretation result of Yan 9 reservoir in Hujianshan area of Ordos Basin, by combining the current well production performance, logging, oil test, production test and other data, on the basis of making full use of core, coring, logging, thin section analysis and high pressure mercury injection data, the four characteristics of reservoir are analyzed, a more scientific and reasonable calculation model of reservoir logging parameters is established, and the reserves are recalculated after the second interpretation standard of logging is determined. The research improves the accuracy of logging interpretation and provides an effective basis for subsequent production development and potential horizons.

Phthalocyanine-derived catalysts decorated by metallic nanoclusters for enhanced CO_(2)electroreduction

Electrochemical CO_(2)reduction(CO_(2)RR)over molecular catalysts is a paramount approach for CO_(2)conversion to CO.Herein,we report a novel phthalocyanine-derived catalyst synthesized by a two-step method with a much improved electroconductivity.Furthermore,the catalyst contains both Ni-N4sites and highly dispersed metallic Ni nanoclusters,leading to an increased CO_(2)RR currents by two folds.Isotope labelling study and in situ spectroscopic analysis demonstrate that the existence of metallic Ni nanoclusters is the key factor for the activity enhancement and can shift the CO_(2)RR mechanism from being electron transfer(ET)-limited(forming*COO^(-))to concerted proton-electron transfer(CPET)-limited(forming CO).

The design and application of BIM+refined management and control platform for the Jingxiong railway bridge

The high-speed railway construction involves multiple professional fields,such as railway design,construction,and supervision.This paper architects the"BIM+"project refined management platform,designs the platform's logical architecture,physical architecture,and solves several key technology difficulties.This"BIM+"platform has been applied on the Jingxiong Bridge Project and achieved all-round,whole-process and multi-management of high-speed railway engineering construction.It significantly improves the level of construction management,and plays a role in promoting the development of high-speed railway construction informatization.

Biomimetic Infiltrating Surface Construction Based on Micro and Nano Structures

Microfluidic chips hold significant potential for applications in various fields, such as biological analysis, chemical separation, and drug screening. Here, we draw inspiration from the natural ability of aquatic plants to capture different substances in streams, focusing on the design and fabrication of surfaces with micron and nano-scale structures to mimic the wetting phenomenon observed in nature, thereby achieving the capture and separation of specific substances. This paper reports on the self-assembly of magnetic nanoparticles, the preparation of flexible magnetic nano-chains, and the modification of microfluidic chip surfaces, providing a novel perspective and approach to microfluidic chip technology.

Chiral Dirac Fermion in a Collinear Antiferromagnet

In a Dirac semimetal, the massless Dirac fermion has zero chirality, leading to surface states connected adiabatically to a topologically trivial surface state as well as vanishing anomalous Hall effect. Recently, it is predicted that in the nonrelativistic limit of certain collinear antiferromagnets, there exists a type of chiral“Dirac-like” fermion, whose dispersion manifests four-fold degenerate crossing points formed by spin-degenerate linear bands, with topologically protected Fermi arcs. Such an unconventional chiral fermion, protected by a hidden SU(2) symmetry in the hierarchy of an enhanced crystallographic group, namely spin space group, is not experimentally verified yet. Here, by angle-resolved photoemission spectroscopy measurements, we reveal the surface origin of the electron pocket at the Fermi surface in collinear antiferromagnet CoNb3S6. Combining with neutron diffraction and first-principles calculations, we suggest a multidomain collinear antiferromagnetic configuration, rendering the the existence of the Fermi-arc surface states induced by chiral Dirac-like fermions.Our work provides spectral evidence of the chiral Dirac-like fermion caused by particular spin symmetry in CoNb_(3)S_(6), paving an avenue for exploring new emergent phenomena in antiferromagnets with unconventional quasiparticle excitations.

Designing simple non-fused terthiophene-based electron acceptors for efficient organic solar cells

Low-cost photovoltaic materials are essential for realizing large-scale commercial applications of organic solar cells(OSCs).However,highly efficient OSCs based on low-cost photovoltaic materials are scarce due to a deficiency in understanding the structure-property relationship.Herein,we investigated two low-cost terthiophene-based electron acceptors,namely,3TC8 and 3TEH,with 3,4-bis(octan-3-yloxy)thiophene,differing only in the alkylated thiophene-bridges.Both acceptors exhibit low optical gaps(∼1.43 eV)and possess deep highest occupied molecular orbital(HOMO)levels(∼−5.8 eV).Notably,the single-crystal structure of 3TEH demonstrates highly planar conjugated backbone and strongπ-πstacking between intermolecular terminal groups,attributed to the presence of the bulky alkylated noncovalently conformational locks.Upon utilizing both acceptors to fabricate OSCs,the 3TC8-based device exhibited a power conversion efficiency(PCE)of 11.1%,while the 3TEH-based OSC demonstrated an excellent PCE of 14.4%.This PCE is the highest among OSCs based on terthiophene-containing electron acceptors.These results offer a new strategy for designing low-cost electron acceptors for highly efficient OSCs.

Research Progress on the Bone Metastasis Mechanism of Prostate Cancer and Bone-Targeted Drugs

Prostate cancer is a common male malignant tumor,and bone metastasis is one of the common complications in the late stage of prostate cancer.The mechanism of prostate cancer bone metastasis is a complex process involving multiple factors and steps.In recent years,with in-depth research on the mechanism of prostate cancer bone metastasis and the development of new drugs,important progress has been made in the treatment of prostate cancer bone metastasis.Based on this,this article introduces the mechanism of prostate cancer bone metastasis and the research progress of several bone-targeted drugs to provide reference and inspiration for future research.

Secure Multigroup Multicast Communication Systems via Intelligent Reflecting Surface

This paper considers a secure multigroup multicast multiple-input single-output(MISO)communication system aided by an intelligent reflecting surface(IRS).Specifically,we aim to minimize the transmit power at Alice via jointly optimizing the transmit beamformer,artificial noise(AN)vector and phase shifts at the IRS subject to the secrecy rate constraints as well as the unit modulus constraints of IRS phase shifts.To tackle the optimization problem,we first transform it into a semidefinite relaxation(SDR)problem,and then alternately update the transmit beamformer and AN matrix as well as the phase shifts at the IRS.In order to reduce the high computational complexity,we further propose a low-complexity algorithm based on second-order cone programming(SOCP).We decouple the optimization problem into two sub-problems and optimize the transmit beamformer,AN vector and the phase shifts alternately by solving two corresponding SOCP subproblem.Simulation results show that the proposed SDR and SOCP schemes require half or less transmit power than the scheme without IRS,which demonstrates the advantages of introducing IRS and the effectiveness of the proposed methods.

Application of low-cost particulate matter sensors for air quality monitoring and exposure assessment in underground mines:A review

Exposure to mining-induced particulate matter(PM)including coal dust and diesel particulate matter(DPM)causes severe respirat-ory diseases such as coal workers’pneumoconiosis(CWP)and lung cancer.Limited spatiotemporal resolution of current PM monitors causes miners to be exposed to unknown PM concentrations,with increased overexposure risk.Low-cost PM sensors offer a potential solution to this challenge with their capability in characterizing PM concentrations with high spatiotemporal resolution.However,their application in underground mines has not been explored.With the aim of examining the potential application of low-cost sensors in underground mines,a critical review of the present status of PM sensor research is conducted.The working principles of present PM monitors and low-cost sensors are com-pared.Sensor error sources are identified,and comprehensive calibration processes are presented to correct them.Evaluation protocols are pro-posed to evaluate sensor performance prior to deployment,and the potential application of low-cost sensors is discussed.

Carrimycin inhibits coronavirus replication by decreasing the efficiency of programmed–1 ribosomal frameshifting through directly binding to the RNA pseudoknot of viral frameshift-stimulatory element

The pandemic of SARS-CoV-2 worldwide with successive emerging variants urgently calls for small-molecule oral drugs with broad-spectrum antiviral activity.Here,we show that carrimycin,a new macrolide antibiotic in the clinic and an antiviral candidate for SARS-CoV-2 in phase III trials,decreases the efficiency of programmed–1 ribosomal frameshifting of coronaviruses and thus impedes viral replication in a broad-spectrum fashion.Carrimycin binds directly to the coronaviral frameshift-stimulatory element(FSE)RNA pseudoknot,interrupting the viral protein translation switch from ORF1a to ORF1b and thereby reducing the level of the core components of the viral replication and transcription complexes.Combined carrimycin with known viral replicase inhibitors yielded a synergistic inhibitory effect on coronaviruses.Because the FSE mechanism is essential in all coronaviruses,carrimycin could be a new broad-spectrum antiviral drug for human coronaviruses by directly targeting the conserved coronaviral FSE RNA.This finding may open a new direction in antiviral drug discovery for coronavirus variants.

A modular approach to efficient thermally activated delayed fluorescence from metal-perturbed intraligand charge-transfer excited state of Au(Ⅰ)complexes

The efficient harvesting of triplet excitons is crucial to the realization of high-performance organic light-emitting diodes(OLEDs).Herein,we show that coordination of donor-acceptor(D-A)type molecules to a metal atom in a monodentate fashion can lead to thermally activated delayed fluorescence(TADF)emissions with wide color tunability only through varying the noncoordinating acceptor moiety.A panel of TADF gold(Ⅰ)complexes with emission maxima(λmax)of 545–645 nm from metal perturbed intraligand charge-transfer(MPICT)excited states have been developed.Synergetic effects of heavy atom-induced spin-orbit coupling(SOC),steric-induced donor-acceptor twisting and suppressed intramolecular motions lead to high emission efficiencies of 65%-85%in doped films with delayed fluorescence lifetime of as short as 2.0μs.Transient absorption spectroscopic studies on selected complexes determined the kISCto be 6.5×10^(9)s^(-1).Theoretical calculations confirmed the participation of minor d orbital into the lowest excited state,which led to an SOC value of 5.19 cm^(-1)between the lowest-lying singlet and triplet excited states.The yellow to deep red solution-processed OLEDs based on the new gold(Ⅰ)complexes incorporated with various D-A ligands demonstrated promising performances.This study validates a modular design for TADF metal complexes,which will broaden the choices of metal centers and allow for facile color tuning via simple ligand synthesis.

Preparation of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials by Hydrothermal Assisted Sol-Gel Method for Sodium -Ion Batteries

Na_(3)V_(2)(PO_(4))_(3)(NVP)cathode material of the sodium ion battery(1 C=117 mAh g-1)has a NASICON-type structure,which not only facilitates the rapid migration of sodium ions,but also has a small volume deformation during sodium ion de-intercalation and the main frame mechanism remains unchanged,and thus is seen as an energy storage material for a wide range of applications,but has a limited electronic conductivity due to its structure.In this paper,NVP cathode materials with finer primary particles are successfully prepared using a simple hydrothermal treatment-assisted sol-gel method.The increased pore size of the NVP materials prepared under the hydrothermal process allows for more active sites and more effective resistance to the volume deformation of sodium ions during insertion/extraction processes,effectively facilitating the diffusion of ions and electrons.The Na_(3)V_(2)(PO_(4))_(3) material obtained by the optimized process exhibited good crystallinity in XRD characterization,as well as superior electrochemical properties in a series of electrochemical tests.A specific capacitance of 106.3 mAh g^(-1) at 0.2 C is demonstrated,compared to 96.5 mAh g^(-1) for Na_(3)V_(2)(PO_(4))_(3) without hydrothermal treatment,and cycling performance is also improved with 93%capacity retention.The calculated sodium ion diffusion coefficient(DNa=5.68×10^(-14))obtained after EIS curve fitting of the improved sample illustrates that the pore structure is beneficial to the performance of the Na_(3)V_(2)(PO_(4))_(3)cathode material.

Design of High Precision CNC Vertical Lathe Turning Tool Holder

A large aspect ratio vibration reducing tool holder based on passive damping vibration reduction technology is designed to solve the vibration problem that occurs in deep hole machining of vertical lathes.A dynamic model of passive damping vibration reduction tool holder was established,and the optimal damping ratio,optimal frequency ratio,and maximum relative amplitude were derived.Modal analysis of the passive damping vibrationreduction tool holder was conducted using software.The results showed that the maximum response amplitude of the passive damping vibration reduction tool holder decreased significantly compared to the original one.

疏水性增透聚酯薄膜的制备及应用

以聚苯乙烯为大分子引发剂,丙烯酸聚硅氧烷酯为单体,通过原子转移自由基聚合制备苯乙烯-丙烯酸聚二甲基硅氧烷酯共聚物。将所得聚合物旋涂于聚对苯二甲酸乙二醇酯(PET)薄膜表面,研究共聚物中不同硅氧烷含量对聚酯薄膜性能的影响。通过核磁共振和红外光谱表征了丙烯酸聚硅氧烷酯单体及与苯乙烯共聚产物的结构,结果表明实验成功制备出了苯乙烯共聚物;凝胶渗透色谱结果表明聚合物的相对分子质量与设计相对分子质量相接近,并且相对分子质量分布系数均小于1.4,说明反应具有一定可控性;紫外-可见光分光光度计结果表明聚合物的折射率随着嵌段聚合物中硅氧烷含量的降低而增加;通过场发射扫描电镜(FE-SEM)对改性前后的聚酯薄膜进行观察,结果显示聚酯薄膜表面形成了蜂窝状多孔结构,从而有效改善了薄膜的透光性。总体研究结果表明,随着共聚物中硅氧烷含量的增加,聚酯薄膜的水接触角和透光率均呈先增后减的趋势。当共聚物中硅氧烷含量为19.6%时,PS-PDMS嵌段共聚物折射率为1.38,涂覆在PET表面后薄膜透光率达到92.6%,水接触角为120°。

Caprini风险评估模型预测恶性肿瘤住院患者深静脉血栓形成的确证性研究

目的:评估Caprini风险评估模型在恶性肿瘤患者中预测深静脉血栓形成的有效性。方法:对2015年1月至2017年1月在首都医科大学附属北京世纪坛医院住院的504例恶性肿瘤患者进行深静脉血栓筛查,分析Caprini血栓风险模型评分和危险分级,并与Khorana模型进行比较。结果:深静脉血栓形成患者的Caprini得分中位数为6(4~8)分,高于无深静脉血栓组的5(4~7)分(P=0.004)。低中危、高危、极高危组的深静脉血栓形成发生率的差异具有统计学意义(Z=-1.933,P=0.053)。Caprini评分的接收者操作特征曲线下面积(area under ROC curve,AUC)为0.611(95%CI:0.54~0.69,P=0.004),截断值为6分时,约登指数最大。Khorana模型的AUC为0.65(95%CI:0.57~0.72,P<0.001),与Caprini模型的差异无统计学意义(Z=0.674,P=0.50)。在恶性肿瘤手术患者中,Caprini模型的AUC为0.85(95%CI:0.66~0.96,P<0.01),Khorana模型为0.68(95%CI:0.47~0.84,P=0.18);对于非手术接受化疗患者,Khorana模型的AUC为0.72(95%CI:0.61~0.82,P=0.01),Caprini模型为0.55(95%CI:0.44~0.67,P=0.54)。结论:Caprini和Khorana风险评估模型均具有一定的预测价值,但区分度不高。在接受手术的肿瘤患者中Caprini具有更好的预测性。Khorana模型适合非手术化疗患者。Caprini模型在恶性肿瘤患者中的应用有待进一步深入研究。

Application of three Ln(Ⅲ)-coordination polymers in fields of luminescence,antibacteria and detection of Fe^(3+) and 4-nitrophenol

Three lanthanide-based coordination polymers(Ln-CPs) with layered structure,{[La_(2)(L)_(3)(DMF)(H_(2)O)_(3)]·H_(2)O}_n(1),{[Eu_(2)(L)_(3)(DMF)_(2)(H_(2)O)]·(H_(2)O)}_n(2){Tb_(2)(L)_(3)(DMF)_(2)(H_(2)O)]·H_(2)O}n(3) were successfully synthesized from H_(2)L(N,N'-bis(4-carbozylbenzyl)aniline).Remarkably,compound 3 has extremely high sensitivity to 4-nitrophenol.When the concentration of 4-nitrophenol reaches 5.98 × 10^(-3) mmol/L,the fluorescence intensity of compound 3 is quenched by 59%.The calculated K_(SV) is 7.56 × 10~4 and limit of detection(LOD) is 4.73 μg/L.3 exhibits a highly sensitive detection towards Fe^(3+) and compound 2 shows outstanding antibacterial effects on Staphylococcus aureus,re spectively.The white light emission was also investigated by changing the mixing ratio of LaNO_(3),EuNO_(3) and TbNO_(3) during the preparation of coordination polymers.

基于MEH-PPV:PCBM体异质结的有机人工光电突触

在识别与处理视觉信息、完成复杂的学习和记忆方面,集光学传感和突触功能于一体的人工光电突触表现出巨大的优势.目前已报道的光突触器件功能实现形式相对单一且不稳定,因此需要探索更多基于新材料和新结构的突触器件,以处理复杂多变的视觉信息.本研究采用了有机半导体材料聚[2-甲氧基-5-(2-乙基己氧基)-1,4-苯乙炔](MEH-PPV)和[6,6]-苯基C61丁酸甲酯(PCBM)构建垂直型光调控忆阻器,展现了其在处理视觉信息和模拟神经形态行为方面的优异性能.该器件通过体异质结实现了稳定、缓变的阻值变化,成功模拟了电压调控的长时程增强/抑制,呈现多种光电协同调控的突触可塑性.此外,该器件还成功模拟了人类视觉神经系统中的图案识别与记忆功能,证明了其在开发下一代人工视觉系统方面的应用潜力.

Design of Automatic Sorting System of Workpiece Based on Multi-sensor Detection

The sorting system applies multi-sensor technology,PLC technology,pneumatic technology and frequency converter technology to realize the efficient automatic sorting of workpieces and solve the problem of automatic sorting of more complex shaped products.Through running test,the system has high efficiency,reliable operation,strong practicability,and great application value in automatic production lines such as mechanical processing,electronic assembly and article circulation.