农户认知、政策信任与教育扶贫清单执行绩效——基于河南省20村1542户贫困农户的实证调查

本文运用河南省20个村1542户贫困农户的调查数据建构有序logit模型,分析了农户认知、政策信任与教育扶贫清单执行绩效的关系。研究结果显示,教育扶贫清单的政策执行绩效受农户个体特征、家庭类型以及政策信任等多重影响。具体而言,女性对扶贫清单的满意度高于男性,教育扶贫政策执行绩效满意度不会随农户年龄增大而提高。与兼业户相比,纯农业户对教育扶贫清单执行的满意度较高。教育水平越高、家庭人口数越多的贫困农户对教育扶贫清单政策执行越满意。家庭收入、教育支出和健康状况三个变量对教育扶贫清单的执行均不具有显著影响,该结果凸显了贫困农户对教育投资的刚性需求和脱贫理性。在教育扶贫清单信任变量中,教育扶贫清单的执行主体、过程与结果均对扶贫效果影响较大。从教育扶贫清单的内容看,农户对资金助学政策的评价较为满意,对技术培训以及职业教育政策的需求意愿较为强烈。因此,要不断拓展教育资源配置精准化的公共性价值,提升农户对基层政府的信任,对教育扶贫清单的运作绩效进行精准监测和及时回应。

Use of the ulcerative colitis endoscopic index of severity and Mayo endoscopic score for predicting the therapeutic effect of mesalazine in patients with ulcerative colitis

Objective:The ulcerative colitis endoscopic index of severity(UCEIS)and the Mayo endoscopic score(MES)are developed as objective methods of evaluating endoscopic severity in patients with ulcerative colitis(UC).The aim of this study is to investigate the diagnostic accuracy of the UCEIS and MES in predicting the patient's response to mesalazine.Methods:Consecutive patients with UC who had undergone colonoscopy within 1 month before starting mesalazine between October 2011 and July 2016 were retrospectively collected at the Department of Gastroenterology,Sir Run Run Shaw Hospital,Zhejiang University School of Medicine.The median follow-up was 81 months,and all the data were analyzed in January 2021.The primary outcome was the need for step-up treatment,which included the use of corticosteroids,immunomodulatory,or surgery during admission and follow-up.Data were analyzed using the c2 or Fisher exact test,Spearman test,t-test,and ManneWhitney U test.Results:Totally,65 patients were enrolled,of whom 12(18.5%)needed step-up treatment due to nonresponse to mesalazine.The UCEIS score,MES,and the ulcerative colitis disease activity index(UCDAI)score were significantly higher in patients who had nonresponse to mesalazine(UCEIS score:6.92±0.69 vs.4.45±1.17,p<0.001;MES:2.67±0.49 vs.2.15±0.69,p=0.024;UCDAI score:9.33±1.87 vs.6.70±2.38,p=0.002).In the multivariate analysis,the UCEIS score(OR=25.65,95%CI:3.048 e45.985,p=0.003),UCDAI score(OR=1.605,95%CI:1.144e2.254,p=0.006),and C-reactive protein level(OR=1.056,95%CI:1.006e1.108,p=0.026)were independent risk factors of nonresponse.The area under the ROC curve of UCEIS was 0.95,with a sensitivity of 100%and specificity of 84.6%,a cut-off value of 6,which outperformed the MES with an area under the ROC curve of 0.70.When the UCEIS score≥6,60%of patients eventually needed step-up treatment.Conclusions:The UCEIS is a useful instrument for predicting the therapeutic effect in patients with UC treated with mesalazine.The high probability of mesalazine treatment failure and benefits of other therapies should be discussed in patients with baseline UCEIS score≥6.

Formation process and mechanical properties in selective laser melted multi-principal-element alloys

Additive manufacturing is believed to open up a new era in precise microfabrication,and the dynamic microstructure evolution during the process as well as the experiment-simulation correlated study is conducted on a prototype multi-principal-element alloys FeCrNi fabricated using selective laser melting(SLM).Experimental results reveal that columnar crystals grow across the cladding layers and the dense cellular structures develop in the filled crystal.At the micron scale,all constituent elements are evenly distributed,while at the near-atomic scale,Cr element is obviously segregated.Simulation results at the atomic scale illustrate that i)the solid-liquid interface during the grain growth changes from horizontal to arc due to the radial temperature gradient;ii)the precipitates,microscale voids,and stacking faults also form dynamically as a result of the thermal gradient,leading to the residual stress in the SLMed structure.In addition,we established a microstructure-based physical model based on atomic simulation,which indicates that strong interface strengthening exists in the tensile deformation.The present work provides an atomic-scale understanding of the microstructural evolution in the SLM process through the combination of experiment and simulation.

高熵合金强韧化理论建模与模拟研究进展

高熵合金因其优异的性能受到广泛关注,如高强度、高硬度、高韧性、高耐磨、高耐辐照、高耐腐蚀、高电阻、高耐热等,有望应用于核能、航天航空等重要领域和重大装备.高熵合金制备、组织结构以及性能表征等方面开展的实验研究表明其独特的性质依赖于高熵合金高熵效应、晶格畸变和扩散迟滞.在微观尺度以及宏观尺度,理论模型和数值模拟为研究高熵合金微观机理和力学特性提供了一种方法.建立从高熵合金的微观结构与变形机理到宏观独特力学性能的联系是一个多尺度的科学问题.最近,基于实验观察结果,采用多尺度的理论与模拟方法(第一性原理、分子动力学、离散位错动力学、晶体塑性有限元、微结构依赖的理论模型),研究了高熵合金层错能、弹性模量、扩散系数以及相稳定性,揭示了高熵合金变形与强韧化机制.论文综述多尺度计算在高熵合金力学性能和变形行为方面的研究进展,并对高熵合金在原位变形实验、高通量技术以及机器学习方面的研究进行简要展望.

Decoding Cortical Glial Cell Development

Mouse cortical radial glial cells(RGCs)are primary neural stem cells that give rise to cortical oligodendrocytes,astrocytes,and olfactory bulb(OB)GABAergic interneurons in late embryogenesis.There are fundamental gaps in understanding how these diverse cell subtypes are generated.Here,by combining single-cell RNA-Seq with intersectional lineage analyses,we show that beginning at around E16.5,neocortical RGCs start to generate ASCL1^(+)EGFR^(+)apical multipotent intermediate progenitors(MIPCs),which then differentiate into basal MIPCs that express ASCL1,EGFR,OLIG2,and MKI67.These basal MIPCs undergo several rounds of divisions to generate most of the cortical oligodendrocytes and astrocytes and a subpopulation of OB interneurons.Finally,single-cell ATAC-Seq supported our model for the genetic logic underlying the specification and differentiation of cortical glial cells and OB interneurons.Taken together,this work reveals the process of cortical radial glial cell lineage progression and the developmental origins of cortical astrocytes and oligodendrocytes.

Controlled fabrication of nanoscale wrinkle structure by fluorocarbon plasma for highly transparent triboelectric nanogenerator

In this paper,we report a novel nanoscale wrinkle-structure fabrication process using fluorocarbon plasma on poly(dimethylsiloxane)(PDMS)and Solaris membranes.Wrinkles with wavelengths of hundreds of nanometers were obtained on these two materials,showing that the fabrication process was universally applicable.By varying the plasma-treating time,the wavelength of the wrinkle structure could be controlled.Highly transparent membranes with wrinkle patterns were obtained when the plasmatreating time was o125 s.The transmittances of these membranes were 490%in the visible region,making it difficult to distinguish them from a flat membrane.The deposited fluorocarbon polymer also dramatically reduced the surface energy,which allowed us to replicate the wrinkle pattern with high precision onto other membranes without any surfactant coating.The combined advantages of high electron affinity and high transparency enabled the fabricated membrane to improve the performance of a triboelectric nanogenerator.This nanoscale,single-step,and universal wrinkle-pattern fabrication process,with the functionality of high transparency and ultra-low surface energy,shows an attractive potential for future applications in microand nanodevices,especially in transparent energy harvesters.

Microstructure evolution and deformation mechanism of amorphous/crystalline high-entropy-alloy composites

High-entropy amorphous alloys present high hardness,but low tensile ductility.Here,deformation behavior of the amorphous/crystalline Fe Co Cr Ni high-entropy alloy(HEA)composite prepared by the previous experiment is investigated using atomic simulations.The result shows the partial dislocations in the crystal HEA layer,and the formation of shear bands in the amorphous HEA layer occurs after yielding.The strength of the amorphous/crystalline HEA composite reduces with increasing the thickness of the amorphous layer,agreeing with the previous experiments.The coupled interaction between the crystal plasticity and amorphous plasticity in amorphous/crystalline HEA composites results in a more homogeneous redistribution of plastic deformation to cause interface hardening,due to the complex stress field in the amorphous layer.The current findings provide the insight into the deformation behavior of the amorphous/crystalline HEA composite at the nanoscale,which are useful for optimizing the structure of the HEA composite with high strength and good plasticity.

Self-ignition characteristics of the high-speed ramjet kinetic energy projectile in the launch process

To research the self-ignition characteristics of high-speed ramjet kinetic energy projectile in the launch process, the self-ignition process based on the solid fuel of polyethylene was numerically simulated by using the dynamic grid technology. The effect of different muzzle velocity on the self-ignition performance, and the effect of opening the blockage at different times on the flow field stability of the combustion chamber and the flow field characteristics after the solid fuel ramjet stabilized were analyzed. The results show that the occurrence of self-ignition is not only related to the pressure, temperature in the combustion chamber, and the muzzle velocity, but also to the content of C_2H_4 and its degree of mixing with air in the combustion chamber. After the kinetic energy projectile gets out of the muzzle and before the blockage opens, there is oscillation occurring in the combustion chamber. The higher the muzzle velocity of the kinetic energy projectile, the more prone to the occurrence of the self-ignition and the negative effects can be avoided due to the pressure oscillation in the combustion chamber. The effect of opening the blockage at different times on the flow field stability after the self-ignition occurs in a period of time is weak. After the blockage opens, the solid fuel ramjet can reach a stable working condition quickly.

Homeobox Gene Six3 is Required for the Differentiation of D2-Type Medium Spiny Neurons

Medium spiny neurons(MSNs)in the striatum,which can be divided into D1 and D2 MSNs,originate from the lateral ganglionic eminence(LGE).Previously,we reported that Six3 is a downstream target of Sp8/Sp9 in the transcriptional regulatory cascade of D2 MSN development and that conditionally knocking out Six3 leads to a severe loss of D2 MSNs.Here,we showed that Six3 mainly functions in D2 MSN precursor cells and gradually loses its function as D2 MSNs mature.Conditional deletion of Six3 had little effect on cell proliferation but blocked the differentiation of D2 MSN precursor cells.In addition,conditional overexpression of Six3 promoted the differentiation of precursor cells in the LGE.We measured an increase of apoptosis in the postnatal striatum of conditional Six3-knockout mice.This suggests that,in the absence of Six3,abnormally differentiated D2 MSNs are eliminated by programmed cell death.These results further identify Six3 as an important regulatory element during D2 MSN differentiation.

A Gyrokinetic simulation model for low frequency electromagnetic fluctuations in magnetized plasmas

We present a new model for simulating the electromagnetic fluctuations with frequencies much lower than the ion cyclotron frequency in plasmas confined in general magnetic configurations.This novel model(termed as GK-E&B)employs nonlinear gyrokinetic equations formulated in terms of electromagnetic fields along with momentum balance equations for solving fields.It,thus,not only includes kinetic effects,such as wave-particle interaction and microscopic(ion Larmor radius scale)physics;but also is computationally more efficient than the conventional formulation described in terms of potentials.As a benchmark,we perform linear as well as nonlinear simulations of the kinetic Alfvén wave;demonstrating physics in agreement with the analytical theories.

A strategy to design eutectic high-entropy alloys based on binary eutectics

1.Introduction As an ancient method for manufacturing metallic materials,casting has the advantages of low cost,high process flexibility and forming complex parts.However,due to the poor as-cast mechanical properties,various processes after casting are generally necessary for traditional metallic materials to eliminate casting defects(e.g.,voids,shrinkage cavities and elemental segregation)and improve their properties,such as rolling,forging,and heat treatment.