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Expanding employment channels for rural households is a crucial means of enhancing the income of rural residents and enhancing the quality of rural employment. This study examines the impact of digital skills on rural laborers’ employment choices and explores the underlying mechanisms by using data from the China Family Panel Studies (CFPS) spanning 2014–2018. By employing various models, including the Probit, IV, mediated effects, and propensity-score-matching methods, the study reveals that digital skills have a significant impact on rural laborers’ employment choices. Specifically, digital skills increase rural labor’s employment opportunities in nonfarm and employed employment while reducing the proportion of informal employment. Additionally, the analysis indicates that the main channels through which digital skills influence rural labor’s employment choices are human and social capital. A heterogeneity analysis further reveals that work-study and social-entertainment skills have a more significant effect on rural laborers’ nonfarm and employed employment opportunities while inhibiting informal employment. Hence, to enhance the quality of future rural employment, the government must encourage rural workers to enhance their digital literacy and digital application skills while improving digital infrastructure.

Stem color is an important agronomic trait in zucchini ( Cucurbita pepo , C. pepo ) for robust seedings and high yield. However, the gene controlling this trait has not been characterized. This study identified a single locus accounting for dark green stem color in C. pepo ( CpDsc-1 ). Genetic analysis of this trait in segregation populations derived from two parental lines (line 296 with dark green stem and line 274 with light green stem) revealed that it was controlled by a single dominant gene (dark green vs. light green). Using the bulked segregant analysis method, CpDsc-1 was mapped to a 2.09 Mb interval on chromosome 15. Then this region was further narrowed down to 65.2 kb using linkage analysis in the F 2 population. Sequencing analysis revealed a 14 kb deletion between Cp4.1LG15g03420 and Cp4.1LG15g03360 , encoding a two-component response regulator-like protein (APRR2). The incomplete structures of the two APRR2 genes and the abnormal chloroplasts in line 274 might be the main reason for the light green phenotype. Gene expression pattern analysis showed that only Cp4.1LG15g03420 was upregulated in line 296. The subcellular localization analysis indicated that Cp4.1LG15g03420 was a nuclear gene. Furthermore, a co-dominant marker G4563 (93% accuracy rate) and a co-segregation marker Fra3 were established in 111 diverse germplasms, and both were tightly linked with the color trait. This study provide new insight into the chlorophyll regulation pathway, and these markers would be valuable for marker-assisted selection in zucchini breeding.

Cp4.1LG15g03420 (CpDsc-1), which encodes a two-component response regulator-like protein (APRR2) in the nucleus, influences dark green stem formation in Cucurbita pepo by regulating the chlorophyll content. Stem color is an important agronomic trait in zucchini (Cucurbita pepo) for robust seeding and high yield. However, the gene controlling the stem color has not been characterized. In this study, we identified a single locus accounting for the dark green stem color of C. pepo (CpDsc-1). Genetic analysis of this trait in segregated populations derived from two parental lines (line 296 with dark green stems and line 274 with light green stems) revealed that stem color was controlled by a single dominant gene (dark green vs. light green). In bulked segregant analysis, CpDsc-1 was mapped to a 2.09-Mb interval on chromosome 15. This region was further narrowed to 65.2 kb using linkage analysis of the F

A floating raft is a complicated multilayer vibration isolation system, which is often simplified as a two-degree-of-freedom viscous damping system in analysis. In order to research the influences of the hysteretic damping and the raft flexibility on the vibration isolation effect, a three-degree of freedom hysteretic mechanical model of the floating raft is established, and the impedance method is adopted to deduce the model of the force transmissibility of the floating raft. The analytic calculation methods of force transmissibility are given aiming at the low-frequency range, the resonance range, and the high-frequency range, respectively. Finally, the influence rules of damping, mass, and stiffness on force transmissibility are analyzed aiming at the value range of parameters of most floating rafts. The main analysis conclusions are listed as follows: the analytic calculation equation for resonance frequency and resonance peak is accurate; the vibration isolation effect of the high frequency range is determined by the entire floating raft, the unconstrained raft, the inherent frequency of the equipment, the mass ratio between the raft and the equipment only; the hysteretic damping can reduce the force transmissibility at the place of the resonance frequency of the floating raft, which shall be maximized; the increase in the mass of the raft will reduce the force transmissibility during the frequency range above the inherent frequency of the equipment, but it will reduce the marginal benefit; the reduction in the stiffness of the isolator or the raft will reduce the force transmissibility during the frequency range above the inherent frequency of the equipment, and will increase the displacement of the equipment; with limited displacement, it is better to design the isolator and the raft according to the principle of equal stiffness.

The floating raft vibration isolation system includes upper and lower isolators and middle raft. As one of the most important parts that affect the performance of vibration isolation, the raft is usually assumed to be an undamped or viscous damping structure in the analysis, which is different from the actual situation. To study the effects of raft with hysteresis damping characteristics, a three-freedom complex stiffness mechanical model was built, and an approach for calculating the raft's force transmission rate was derived from impedance methods. Based on the mechanical model and a large-sized floating raft, we analysed the effects of raft mass, stiffness and damping on vibration isolation through numerical calculation. Results show that increasing raft mass improved vibration isolation over most frequency ranges; increase in raft stiffness contributed to improved isolation performance over frequency ranges near its low-order natural frequencies, while reduced the performance over higher frequency ranges; and greater raft damping led to enhanced vibration isolation at its natural frequencies and higher frequency ranges.

The Tougu Xiaotong capsule (TXC) is a traditional herbal compound used to treat osteoarthritis (OA) in China. We performed fingerprint analysis with HPLC for the quality control of TXC. Its composition was identified by the comparison of the spectrogram and chromatographic peak of retention time with a reference substance. TXC was found to contain paeoniflorin, isofraxidin, ferulic acid, and rosmarinic acid. The chondrocytes were identified by immunohistochemical staining using collagen II. Chondrocytes that were positive for collagen II were stained brown in the cytoplasm. The toll-like receptor 4 (TLR4) was expressed on the chondrocyte membrane, which was observed using immunofluorescence microscopy. The nuclei were stained blue by 4′,6-diamidino-2-phenylindole (DAPI) and TLR4 was stained green. These were observed using laser scanning confocal microscopy. The successful establishment of LPS-exposed chondrocytes was confirmed using enzyme-linked immunosorbent assay (ELISA). Lipopolysaccharide (LPS) administration significantly reduced the levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), and a maximum effect was observed at 8 h. We believe that these methods will be useful in future investigations of OA. This data article is related to the research article “Tougu Xiaotong capsules may inhibit p38 MAPK pathway-mediated inflammation: In vivo and in vitro verification” [1].

Simple sequence repeats (SSRs) are widely used in mapping constructions and comparative and genetic diversity analyses. Here, 103,056 SSR loci were found in Cucurbita species by in silico PCR. In general, the frequency of these SSRs decreased with the increase in the motif length, and di-nucleotide motifs were the most common type. For the same repeat types, the SSR frequency decreased sharply with the increase in the repeat number. The majority of the SSR loci were suitable for marker development (84.75% in Cucurbita moschata, 94.53% in Cucurbita maxima, and 95.09% in Cucurbita pepo). Using these markers, the cross-species transferable SSR markers between C. pepo and other Cucurbitaceae species were developed, and the complicated mosaic relationships among them were analyzed. Especially, the main syntenic relationships between C. pepo and C. moschata or C. maxima indicated that the chromosomes in the Cucurbita genomes were highly conserved during evolution. Furthermore, 66 core SSR markers were selected to measure the genetic diversity in 61 C. pepo germplasms, and they were divided into two groups by structure and unweighted pair group method with arithmetic analysis. These results will promote the utilization of SSRs in basic and applied research of Cucurbita species.

Citric acid-treated zeolite Y (CY) and zeolite beta were mechanically mixed to obtain composite zeolites (CY-Beta) with various zeolite beta contents. The composite zeolites were used as the acid components of hydrocracking catalyst supports. The physical and chemical properties of the supports and catalysts were analyzed by N2 adsorption-desorption, XRD, SEM, and NH3-TPD. The mechanical mixing of CY and zeolite beta does not destroy the textual properties of the original zeolites. However, the acidity of the composite zeolite does not fit the linearly calculated value of the two zeolites because some of the acid sites are covered or reacted with other acid sites during the mixing process. In addition, weak acid sites favor the high yield of tail oil with low BMCI value. Compared with the CY-based and beta-based catalysts, the conversion and light oil yield of the CY-Beta-based catalyst was increased. The conversion, light oil yield, and petrochemical yield of the Ni-W/20CY-Beta(20)/ASA catalyst are 78.15, 65.0, and 83.7%, respectively. The BMCI value of the tail oil is 4.7, and the aromatic potential content (APC) of heavy naphtha (boiling point 65-177°C) is 42%. The 1,500 h pilot plant test of Ni-W/20CY-Beta(20)/ASA at 350°C, 7.0 MPa, 2.0 h-1 LHSV, and 800 H2/oil (v/v) shows that the activity remains stable during the 1,500 h evaluation. The heavy naphtha (APC about 41.0) yield of 41.2 illustrates that the catalyst has the ability to aromatize and cyclize the light fractions. The yield of diesel is about 25% with a cetane index (CI) of 59.2; the frozen point is lower than -45°C, and the cold filter plugging point is -35°C, demonstrating the isomerization performance for middle distillations. The yield of tail oil is 14.9% with a BMCI of 4.4, showing the high hydrogenation performance of the catalyst to transform the un-cracked tail oil to saturated hydrocarbon in order to reduce the BMCI value.

To capture viscoelastic behavior of polymeric damping materials based on limited dynamic mechanical analysis tests, a simple fractional temperature spectrum model representing the viscoelastic materials is proposed in this paper and experimental tests aims at stressing the validity of the model. The storage modulus, the loss modulus, and the loss factor, are established based on the five-parameter fractional derivative model and the time–temperature superposition principle. The dynamic mechanical tests of two polymeric materials are carried out to verify this temperature spectrum model. Results indicate a good agreement between the temperature spectrum model and experimental tests at various temperature conditions. Furthermore, thermodynamic coupling of the viscoelastic material is investigated by temperature rise calculation and vibration experiment test. Comparison analysis shows that the temperature rise model can simulate the temperature rise process for the shear vibration of the constrained damping, which provide references for the damping capability, thermal damage and failure of viscoelastic material.

Ethnopharmacological relevance Tougu Xiaotong capsules (TXC) are an herbal compound commonly used to treat osteoarthritis (OA) in China. Aim of the study We attempted to verify TXC's therapeutic effects and mechanisms related to the p38 mitogen-activated protein kinase (MAPK) pathway in vivo and in vitro. Materials and methods TXC's therapeutic effects were assessed by observing cartilage degeneration and inflammatory factors in a modified Hulth's model (in vivo) and a lipopolysaccharides (LPS)-exposed cellular model (in vitro). The expression of biomarkers related to p38 MAPK pathway-mediated inflammation was also investigated. Results TXC treatment reversed cartilage degeneration related biomarkers (ADAMTS 4, ADAMTS 5, Col I, Col V, MMP 3, MMP 9, and MMP 13) and inflammation factors (IL-1β, TNF-α, and IL-6) in both the animal and cellular OA models. Expression of p-p38 MAPK was downregulated following TXC administration, and changes to microRNAs in the cellular models were recovered. These results indicated that the p38 MAPK pathway-related mechanism may involve therapeutic effects of TXC. Conclusions This study verified TXC's efficacy to treat OA in vivo and in vitro and suggests that p38 MAPK pathway-related mechanisms may be involved in TXC's therapeutic effects.

Modern semantic segmentation frameworks usually combine low-level and high-level features from pre-trained backbone convolutional models to boost performance. In this paper, we first point out that a simple fusion of low-level and high-level features could be less effective because of the gap in semantic levels and spatial resolution. We find that introducing semantic information into low-level features and high-resolution details into high-level features is more effective for the later fusion. Based on this observation, we propose a new framework, named ExFuse, to bridge the gap between low-level and high-level features thus significantly improve the segmentation quality by 4.0% in total. Furthermore, we evaluate our approach on the challenging PASCAL VOC 2012 segmentation benchmark and achieve 87.9% mean IoU, which outperforms the previous state-of-the-art results.

Implementing vigorously innovation and entrepreneurship of postgraduate is our country’s main strategy position in relying on science and education to rejuvenate the nation and making China an innovative nation. Firstly, the paper based on the idea of “interest-guided and project-oriented”, which structures the training system of ability of innovation and entrepreneurship, relying on research projects and science and technology contests, breaking down the barriers, going to make it more open, practice training, advocating autonomous learning under the guidance of “tutors and seniors”. Secondly, building practice education system based on uniting the university, government and corporations, making the needs of enterprise’s scientific and technological become preliminary research for postgraduates to research, they can improve abilities of practical, self-study, innovation and entrepreneurship in scientific practice. Finally, strengthening process management and supervision to ensure that all kinds of well-designed and continuously improved mechanisms, policies and systems can be implemented. Researching project can create a good academic atmosphere, optimize the training mechanism, improve the teaching quality and enhance self-learning ability, practical ability and innovation and entrepreneurship ability of graduate students.

Molecular simulations are performed to study the self-assembly of particles with discrete, attractive interaction sites − “patches” − at prescribed locations on the particle surface. Chains, sheets, rings, icosahedra, square pyramids, tetrahedra, and twisted and staircase structures are obtained through suitable design of the surface pattern of patches. Our simulations predict that the spontaneous formation of two-dimensional sheets and icosahedra occurs via a first-order transition while the formation of chains occurs via a continuous disorder-to-order transition as in equilibrium polymerization. Our results show how precise arrangements of patches combined with patch “recognition” or selectivity may be used to control the relative position of particles and the overall structure of particle assemblies. In this context, patchy particles represent a new class of building block for the fabrication of precise structures.

A variety of materials variables affect the performance of an automotive lithium ion battery. Some of the most important materials parameters include dynamic transport properties of electrolyte and solid material, including ionic conductivity, electronic conductivity, reaction rate, and lithium diffusivity. Understanding the relationship between changes to these materials parameters and performance of the battery is critical to battery design. In this work, we consider the impact of the sensitivity of these fundamental parameters within the context of two different systems: a power cell for hybrid electric vehicles (HEV) applications, and an energy cell for electric vehicle (EV) applications. These applications are simulated using high-pulse power capability (HPPC) and constant-current discharge tests. The range of variance and sensitivity of key electrochemical parameters are presented.

Optimization of the performance of Micro-hybrid Electric Vehicles (MHEV) requires a close match between the demands of the driving profile and the chemical and engineering characteristics of the material. Typical driving patterns present the opportunity for regenerative braking pulses that may be over 30 seconds in some cases. Our goal is to provide more opportunity for regenerative braking, particularly for high-speed, long deceleration pulses. In this work we have used electrochemical modeling of NMC 1:1:1 cells to investigate the effects of particle size, coating thickness, and system capability on the energy and power capability of lithium ion batteries. We demonstrate a novel metric for evaluating the regeneration capability of a cell – recovered energy per volume, Whrecov/L – against which these effects are optimized. Finally, we have modeled lithium concentration gradients in both the electrolyte and particle surface and have identified conditions under which regeneration capability is affected.

We simulate in three dimensions molecular beam epitaxial (MBE) growth of CdTe/ZnTe/Si using classical molecular dynamics. Atomic interactions are simulated with Stillinger–Weber potentials, whose parameters are obtained by fitting to experimental data or density function theory-calculated distortion energies of the component crystals. The effects of substrate temperature and atomic species flux ratios on epilayer morphology are investigated. The agreement between simulations and experiments suggests that this model has reasonable ability to predict the microstructures of CdTe/ZnTe/Si grown by MBE.

Y/composite titania-silica (CTS) support was prepared by the in situ growth of CTS on HY zeolite. The effects of HY zeolite pretreatment and Y/CTS modification with P and F for adjusting the acidity of the support were studied. The results showed that the structure of Y/CTS was in the form of CTS as shell and HY zeolite particles as core. The content of HY zeolite affected the acidity, acidity distribution and pore structure of Y/CTS. The density of strong acid sites on the HY zeolite surface could be partly reduced by dealumination with citric acid. This reduced the CTS coverage on the outer surface of the HY zeolite, leading to the increased acidity of Y/CTS. The acidity distribution of the support could also be adjusted by P and F modification. Hydrotreating catalysts were prepared with Y/CTS as support. The catalysts were tested using the hydrotreating reaction of a coker gas oil (CGO). The experimental results showed that the catalyst hydrodenitrogenation (HDN) performance could be remarkably improved by adjusting the acidity of the catalyst support via HY zeolite pretreatment and P and F modification. The catalysts with proper Bronsted (B) acidity and Lewis (L) acidity behaved well in hydrodesulfurization (HDS) and HDN performances.

We investigate the self-assembly of anisotropic cone-shaped particles decorated by ringlike attractive "patches". In a recent paper, we demonstrated that the self-assembled clusters, which arise due to the conical particle's anisotropic shape combined with directional attractive interactions, are precise for certain cluster sizes, resulting in a precise packing sequence of clusters of increasing sizes with decreasing cone angles (Chen et al. Proc. Natl. Acad. Sci. U.S.A. 2007, 104, 717-722). Here we explore the dependence of cluster packing on the cone angle and cooling rate and discuss the "stability" and "metastability" of the resulting structures as well as polymorphism of non-"magic-number" clusters. We investigate large clusters of cones and discuss the implication of our simulation results in the context of the Israelachvili packing rule for surfactants and a recent geometrical packing analysis on hard cones in the limit of large numbers of cones.

Recent experiments have demonstrated that nanoparticles with dipoles can self-assemble into interesting one-dimensional and two-dimensional nanostructures. In particular, nanocubes with dipoles are found to form straight nanowires and nanorings with potential applications for nanodevices. In this paper, we use a minimal model to study dipole-induced self-assembly of nanocubes with varying dipole directions, dipole strengths and both with and without face−face attractions arising from dispersive or solvophobic interactions. We reproduce the structures observed in experiments and illustrate that the self-assembled morphologies are dictated by the head-to-tail alignment of the dipoles, the orientation of the dipoles within the cubes, and the face-to-face packing of the nanocubes. Our results show how the self-assembly of dipolar nanocubes differs from that of dipolar spheres in which the only anisotropy is the dipole itself and how system parameters can be manipulated to control the assembled morphologies an...

Molecular simulations of the self-assembly of cone-shaped particles with specific, attractive interactions are performed. Upon cooling from random initial conditions, we find that the cones self assemble into clusters and that clusters comprised of particular numbers of cones (e.g. 4 - 17, 20, 27, 32, 42) have a unique and precisely packed structure that is robust over a range of cone angles. These precise clusters form a sequence of structures at specific cluster sizes- a precise packing sequence - that for small sizes is identical to that observed in evaporation-driven assembly of colloidal spheres. We further show that this sequence is reproduced and extended in simulations of two simple models of spheres self-assembling from random initial conditions subject to certain convexity constraints. This sequence contains six of the most common virus capsid structures obtained in vivo including large chiral clusters, and a cluster that may correspond to several non-icosahedral, spherical virus capsid structures obtained in vivo. Our findings suggest this precise packing sequence results from free energy minimization subject to convexity constraints and is applicable to a broad range of assembly processes., Comment: 23 pages, 3 figures

In their physical dimensions, surface chemistry, and degree of anisotropic interactions in solution, CdTe nanoparticles are similar to proteins. We experimentally observed their spontaneous, template-free organization into free-floating particulate sheets, which resemble the assembly of surface layer (S-layer) proteins. Computer simulation and concurrent experiments demonstrated that the dipole moment, small positive charge, and directional hydrophobic attraction are the driving forces for the self-organization process. The data presented here highlight the analogy of the solution behavior of the two vastly different classes of chemical structures.

New catalysts for deep hydrodesulfurization (HDS) of diesel oil were prepared by loading the active metal components on the TiO2−SiO2 composite supports, which were synthesized by a sol−gel and supercritical fluid drying method. The HDS performance of the prepared catalysts for RFCC (resid fluid catalytic cracking) diesel oils was evaluated in a fixed-bed reactor under different conditions. The major sulfur compounds in the RFCC diesel oils are alkyl substituent benzothiophenes (BTs), dibenzothiophene (DBT), and alkyl substituent dibenzothiophenes (DBTs), in which the alkyl DBTs with alkyl groups at the 4 and/or 6 positions, such as 4,6-DMDBT and 4-MDBT, are the refractory compounds. The effects of the catalyst properties on the HDS performance for different sulfur compounds, especially the refractory compounds, in the diesel oils were studied. It was found that the catalysts supported on TiO2−SiO2 composites with higher ratios of Lewis acid sites and with Ni−W active components presented better HDS perfo...