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As the primary research vehicle, rural tourism is used in this paper to examine urban visitors’ “homesickness.” This research explores the effects of homesickness on tourists’ perceptions of travel destinations and consumption intentions through qualitative analysis, logistic empirical analysis, and questionnaire survey. This work also explores the behavioral traits of customers’ purchase intentions from the perspective of a “big data” environment, and it constructs the relevant consumption behavior model for rural visitors in accordance with those behavioral traits. Through questionnaire design and investigation, this paper makes statistical analysis on tourists’ basic information, expected value, and actual experience and explores the related factors that affect their consumption behavior, so as to understand the consumption behavior law of tourists in rural tourism consumption. The research shows that the MSE (mean squared error) of this algorithm is about 4.16, and the RMSE (root mean square error) of this algorithm is about 0.508. Finally, combining the influence of tourists’ consumption behavior, this paper tries to put forward some countermeasures and suggestions on rural tourism. This paper aims to study the development and planning of rural tourist destinations, and provide corresponding basis for the destination selection of tourists with homesickness.

Macrophages and osteoclasts are both derived from monocyte/macrophage lineage, which plays as the osteoclastic part of bone metabolism. Although they are regulated by bone implant surface nanoarchitecture and involved in osseointegration, the beneath mechanism has not been simultaneously analyzed in a given surface model and their communication with osteoblasts is also blurring. Here, the effect of implant surface topography on monocyte/macrophage lineage osteoclastogenesis and the subsequent effect on osteogenesis are systematically investigated. The nanoporous surface is fabricated on titanium implant by etching and anodizing to get the nanotubes structure. The early bone formation around implant is significantly accelerated by the nanoporous surface in vivo. Meanwhile, the macrophage recruitment and osteoclast formation are increased and decreased respectively. Mechanistically, the integrin mediated FAK phosphorylation and its downstream MAPK pathway (p-p38) are significantly downregulated by the nanoporous surface, which account for the inhibition of osteoclastogenesis. In addition, the nanoporous surface can alleviate the inhibition of osteoclasts on osteogenesis by changing the secretion of clastokines, and accelerate bone regeneration by macrophage cytokine profiles. In conclusion, these data indicate that physical topography of implant surface is a critical factor modulating monocyte/macrophage lineage commitment, which provides theoretical guidance and mechanism basis for promoting osseointegration by coupling the osteogenesis and osteoclastogenesis., Graphical abstract This paper investigates the modulation of osteogenesis by monocyte/macrophage lineage on titanium surface nanoarchitecture. The nanoporous surface promotes bone regeneration by changing the secretion profiles of macrophage (Mϕ) cytokines and clastokines. Mechanistically, the nanoporous surface inhibit the differentiation of macrophages into osteoclasts by blocking integrin mediated FAK phosphorylation and downstream MAPK pathway.Image 1, Highlights • Nanoporous implant inhibits osteoclastogenesis via integrin β1/FAKpY397/MAPK. • Nanoporous implant with larger diameter inhibits osteoclastogenesis more strongly. • Nanoporous implant increases osteogenic cytokines of macrophages/osteoclasts.

Indole-functionalized silver nanoparticles were prepared by a simple one-pot method, which exhibited efficient antibacterial activity against Gram-positive and Gram-negative bacteria.

Carbon materials derived from CoZn-ZIFs were used to load Cu catalysts and were applied for DMC synthesis, and the effects of the graphitization degree and the (N1 + N3)/N2 ratio were studied.

The confinement of Cu nanoparticles in narrow mesopores strengthens the Cu–carbon interactions. This can promote the auto-reduction of CuO to form active Cu2O species, resulting in high activity and stability during DMC synthesis.

The Ni-based catalyst has been intensively studied for CO methanation. Here, MCM-41 is selected as support to prepare xNi/MCM-41 catalysts with various Ni contents and the catalytic performance for CO methanation in a slurry-bed reactor is investigated under different reaction conditions. The CO conversion gradually increases as the reaction temperature or pressure rises. As the Ni content increases, the specific surface area and pore volume of xNi/MCM-41 catalysts decrease, the crystallite sizes of metallic Ni increase, while the metal surface area and active Ni atom numbers firstly increase and then slightly decrease. The 20Ni/MCM-41 catalyst with the Ni content of 20 wt% exhibits the highest catalytic activity for CO methanation, and the initial CH4 yield rate is well correlated to the active metallic Ni atom numbers. The characterization of the spent xNi/MCM-41 catalysts shows that the agglomeration of Ni metal is accountable for the catalyst deactivation.

The performance of CZT in $$\gamma $$ -ray and X-ray detection is growing rapidly in these years. However, there are only a few reports on its utilization in $$\alpha $$ particle detection. Therefore, to study the properties of CZT for detection of $$\alpha $$ particle, a detection system has been manufactured, and a series of simulations have been done. A $$22\times 22\times 0.7 mm^3$$ planar CZT detector is deployed to detect the $$\alpha $$ particles from a radiation source containing Am-241 and Pu-239, while COMSOL MultiPhysics and GEANT4 are employed in the simulation of charge collection and interaction between $$\alpha $$ particles and CZT. An energy resolution of 1.47% FWHM at 5.486MeV and 1.32% at 5.157MeV has been achieved. A simulated spectrum has been created, and it is analogous to the one from experiment. The experiment results show the potential of CZT in $$\alpha $$ detection. The simulations are confirmed effective and will guide a better design of the detecting system.

The slurry bed reactor has many advantages, which make it very suitable for gas-to-liquid processes, especially for the highly exothermic reactions. This chapter reviews three types of slurry bed reactors and their comparisons, including the mechanically stirred slurry reactor, bubble column slurry reactor and three-phase fluidized bed reactor. The application of the slurry bed reactors in carbon one (C1) chemistry for syngas conversion to different valuable chemicals is presented, which includes four typical exothermic reactions, that is, the Fischer-Tropsch synthesis to oil, methanol synthesis, dimethyl ether synthesis and synthetic natural gas synthesis. The operation parameters and performance of slurry bed reactor, fixed bed reactor and fluidized bed reactor are compared while discussing the reasons of catalyst deactivation. Since, the development trend of slurry bed reactor for C1 chemistry is finally proposed.

In this study, we propose a hybrid coded-aperture and Compton camera based on cerium-doped Gd

Metal oxide in a bifunctional catalyst plays crucial roles in catalytic activity for syngas conversion to olefin (STO). Here, ternary co-precipitated CrMnGa oxides with various Cr/Mn ratios were pr...

Shoot apical meristem (SAM) and root apical meristem (RAM) act as pools of stem cells to give rise to aboveground and underground tissues and organs in higher plants. Despite the structure differences between these two meristems, they evolve similar signaling pathways to maintain stem cell homeostasis. The CLAVATA3 (CLV3)-WUSCHEL (WUS) negative feedback loop acts as a core pathway in controlling SAM homeostasis, while CLV3/EMBRYO SURROUNDING REGION (ESR) 40 (CLE40) and WUSCHEL-RELATED HOMEOBOX5 (WOX5), homologues of CLV3 and WUS, direct columella stem cell fate. It has been shown that CLV3 INSENSITIVE KINASES (CIKs) are essential for maintaining SAM homeostasis. Whether CIKs regulate the distal root meristem remains to be elucidated. Here, we report that CIKs are indispensable for transducing the CLE40 signal to maintain homeostasis of the distal root meristem. The cik mutants displayed disrupted quiescent center and delayed columella stem cell (CSC) differentiation. Biochemical assays demonstrated that CIKs interact with ARABIDOPSIS CRINKLY4 (ACR4) in a ligand-independent manner and can be phosphorylated by ACR4 in vitro. In addition, the phosphorylation level of CIKs can be rapidly induced by CLE40, which partially depends on ACR4. Though CIKs act as conserved and redundant regulators in the SAM and RAM, our results demonstrated that they exhibit differentiated functions in these meristems.

The storage performance is important for lithium-ion batteries (LIBs) especially with low voltage at high temperature. We herein studied the phenomenon and mechanism of the swelling of LIBs under different storing conditions. We report a systematic optimization of the performance of LIBs using different electrolytes as additives containing 1,3,2-dioxathiolane 2,2-dioxide (DTD), vinyl ethylene carbonate (VEC), and fluoroethylene carbonate (FEC). Cycling performance and storage performance of LIBs with different electrolytes are studied. The LIB using electrolyte with DTD as additive, which exhibits the highest initial capacity and lowest resistance during cycling, has the lowest swelling ratio after 2-week storage. The LIB using electrolyte with FEC as additive has the highest capacity retention ratio during cycling. The electrolyte additive does play an important role in improving the performance of the LIBs. Single additive cannot solve all the problems of a LIB. This work is expected to provide efficient guides toward smart modulation of multi-functional rechargeable batteries.

A satellite remote imaging data is used to describe the actual ground surface around east of Shandong, based on Barrick’s formulations and Wait’s formulations, and considering the time errors due to elongation of the propagation path caused by mountains, this paper comprehensively analyzes the lightning vertical electric field over the actual ground surface. Furthermore, its effects on time-of-arrival (ToA)-based lighting location systems (LLS) are discussed in details and results show that wave-shape and time-delay of the electromagnetic fields can be significantly affected when they propagate over actual ground surface. The time-delay of the field waveform becomes longer with the increasing roughness, but subtle effect on field peak. After analyzing the actual ground surface around district of Qingdao, this paper reveals the relation between azimuth, observation distance and time-delay. The location error caused by actual ground surface is about several kilometers around the district of Qingdao, and the revised stroke points which are evaluated by the improved actual ground surface propagation model are closer to the actual lightning strike points.

Direct conversion of syngas into light olefins over bifunctional catalysts (metal oxide and zeolite) has attracted great attention in recent years. For this reaction, the adsorption and activation of CO and H2 occur on metal oxide surface, thus the design of metal oxide is crucial. In this study, ternary oxides ZrCeZnOx with various CeO2 contents were prepared by parallel coprecipitation method, and SAPO-34 zeolite (Si/Al = 0.125) was hydrothermally synthesized. The metal oxides were characterized by XRD, BET, TEM, SEM, XPS, CO-TPD, H2-TPD, TGA and in-situ DRIFTS. The addition of CeO2 into Zr-Zn oxide shifted the diffraction peaks to lower values, and formed the Ce0.5Zr0.5O2 solid solution as the Zr/Ce/Zn atomic ratio reached 4/4/1. As the CeO2 content rose, the BET surface area increased while the metal oxide particle size decreased. Moreover, the addition of CeO2 greatly enhanced the concentration of oxygen vacancies and the adsorption ability of CO and H2. The in-situ DRIFTS confirmed that CH3O* was the intermediate. By optimizing the reaction conditions, ZrCeZnOx/SAPO-34 catalyst exhibited high CO conversion of 25.6 % and light olefins selectivity of 78.6 %. This study will contribute to the design of metal oxide for bifunctional catalyst for light olefins synthesis.

It is widely believed that information spread on social media is a percolation process, with parallels to phase transitions in theoretical physics. However, evidence for this hypothesis is limited, as phase transitions have not been directly observed in any social media. Here, through analysis of 100 million Weibo and 40 million Twitter users, we identify percolation-like spread, and find that it happens more readily than current theoretical models would predict. The lower percolation threshold can be explained by the existence of positive feedback in the coevolution between network structure and user activity level, such that more active users gain more followers. Moreover, this coevolution induces an extreme imbalance in users' influence. Our findings indicate that the ability of information to spread across social networks is higher than expected, with implications for many information spread problems., Comment: 15 pages, 3 figures

Transition metal hydroxides have emerged as promising materials in supercapacitor. In this work, a free-standing supercapacitor electrode was prepared. Sea-urchin-like Co(OH)2 microspheres were hydrothermally deposited on a Ni foam substrate, showing a hierarchical 3D free-standing structure. The 3D framework endows the as-prepared electrode with improved supercapacitive performances. The influence of the hydrothermal time on the structure and electrochemical performances of the resulting products are investigated systematically. It delivers a capacitance of 1916 F/g (15.9 F/cm2) and 699 F/g (5.8 F/cm2) at 10 mA/cm2 and 100 mA/cm2, respectively, exhibiting excellent rate performance. The capacitance retains about 79.3% after 5000 charging-discharging cycles at 80 mA/cm2. Various ill-defined rod-like and stacked plate-like CoOOH materials are obtained from the electrodes after the cycles, which is responsible for the property deterioration of Co(OH)2/Ni foam.

Because metal oxides play an important role in the adsorption and activation of CO and H2, binary Mn–Ga metal oxides were prepared and combined with SAPO-34 to study its catalytic performance for syngas conversion into light olefins. The effects of preparation method and precipitant on the Mn–Ga oxides were investigated. The co-precipitated Mn–Ga oxide sample exhibits a higher activity and light olefins selectivity than impregnated Ga/MnOx and Mn/Ga2O3, or the powder mixed MG-(PM), or the solution precursor mixed MG-(SM) samples. For the precipitants, viz., ammonia hydroxide (AH), sodium hydroxide (SH), oxalic acid (OA) and sodium carbonate (SC), the prepared MG-AH and MG-SH oxides exhibit an amorphous structure, strong interaction between the Mn and Ga species and a high concentration of oxygen vacancies. Furthermore, MG-AH possesses the largest amount of desorbed CO and moderate H2 dissociation. Thus, the MG-AH combined with SAPO-34 exhibits the highest CO conversion of 19.5% and the light olefins space-time yield of 116.1 mL h−1 g−1 with a stable activity in a reaction time of 50 h.

Background The proper topography of implant surface can induce macrophages polarization, whereas the regulation mechanism has not been fully deciphered. The study aimed to examine the regulation mechanism of macrophages M2 polarization by titanium (Ti) implant surface micro/nano topography. Results Firstly, the titanium implant micropits-nanotubular surface with ~30 nm diameters (MNT) can induce the M2 polarization of RAW264.7 spontaneously, as indicated by the spindle-like cell morphological alteration and specific molecular marker arginase-1 (Arg1) expression. Next, the autophagic vacuoles (AVs) number is significantly increased on MNT surface, as confirmed by the monodansylcadaverine (MDC) and CYTO-ID staining as well as the transmission electron microscope (TEM) observation. In addition, increasing or decreasing the autophagosomes number by rapamycin or 3-methyladenine (3-MA) will result in augmentation or attenuation of Arg1. Furthermore, blocking the fusion between autophagosomes and lysosomes by bafilomycin also significantly reduces Arg1, even in the presence of rapamycin. Finally, the ERK phosphorylation is selectively upregulated on MNT surface and the AVs number and Arg1 expression are significantly suppressed by U0126 treatment. Conclusion Our findings suggest that the ERK-Beclin-1-autophagy axis may play a pivotal role in the regulation of M2 polarization induced by nanotopography.

Solution combustion synthesis (SCS) possesses many advantages for preparation of nanosized materials. In the process of SCS, a large amount of heat release results in the agglomeration of particles. Thus, the controllable synthesis of solution combustion is necessary. In this study, Ni–Al2O3 nanoparticles with various metal chlorides, i.e., LiCl, NaCl, KCl, MgCl2 and CaCl2, were prepared by SCS method and performed for CO methanation reaction in a slurry-bed reactor. All of the introduced metal chlorides could absorb reaction heat during the combustion process, among which the addition of NaCl minimizes the combustion temperature for its high heat capacity. Moreover, the molten NaCl exerts a steric hindrance effect that restrains the agglomeration of NiO particles, leading to the highest Ni dispersion and smallest Ni particles. MgCl2-added sample exhibits the lowest reducibility and Ni dispersion and the worst methanation activity. The performance shows that, under a harsh condition of 310 °C and 9200 mL (gcat h)−1, NaCl-added Ni–Al2O3 catalyst exhibits the optimal CO conversion, which keeps stable at ca. 87% in a 100-h test. This study offers a new strategy for nanosized catalyst preparation via SCS by introducing metal chlorides.

To minimize the incidence and mortality of cancer, dye trace method was used to explore the mechanism of drug inhibition. 60 mice were selected as the research objects and randomly divided into five groups: model group, shikonin group, aconitine group, notoginsenoside R1 group, and compound group. When establishing the model, begin to administrate the medicine by gavage. The permeability of lung barrier was measured, and H.E staining, immunohistochemical staining, and Western blot test were carried out. The results showed that the mice in model group had decreased autonomic activity, increased permeability of the lung barrier, white nodules on the lung tissue, decreased protein expression related to cell proliferation and differentiation, and decreased protein expression associated with cell proliferation and differentiation, increased expression of related proteins in cancer stem cells, and low level of cell-linked communication. And the incidence of lung cancer in the model group mice was 100%. The histopathological changes in mice were improved to varying degrees after the intervention of the three drugs. Especially in the compound group, the incidence of lung cancer decreased to 8.3%. This study demonstrated that the combination of shikonin, aconitine and notoginsenoside R1 had a good anti-cancer effect, which provided a theoretical basis for clinical research. Keywords: Lung cancer, Mouse model, Dye tracer method, Cancer inhibition mechanism

Objective: The aim of this study was to explore the clinical characteristics of patients with VaIN and identify more sensitive diagnostic methods.Methods: This study retrospectively analyzed 657 patients with VaIN from the International Peace Maternal and Child Health Hospital in Shanghai during a ten-year period. Results: Among the 657 patients, 26.5% were diagnosed with VaIN 2/3. The proportions of patients with VaIN 2/3 among those who did and did not undergo hysterectomy were 39.5% and 24.7%, respectively. The sensitivity of cytology for VaIN in those with only VaIN, VaIN concomitant with cervical or vulvar lesions, and posthysterectomy VaIN was 56.7%, 66.5%, and 72.3%, respectively. The sensitivity of hrHPV for VaIN in the same categories was 87.7%, 86.5%, and 74.3%, respectively. The sensitivity of cytology and hrHPV cotesting for VaIN in the same categories was 95.2%, 95.6%, and 95.0%, respectively. In patients who did not undergo hysterectomy, HPV16 was detected in 9.5% of VaIN 1 lesions among the HPV DNA-positive patients, while the other 12 types of HPV were detected in 62.6% of VaIN 1 lesions. In patients who underwent hysterectomy, HPV16 was detected in 2.1% of VaIN 1 lesions, and the other 12 types of HPV were detected in 54.2% of VaIN 1 lesions.Conclusions: A combination of cytology and colposcopy could increase the sensitivity of the diagnosis of VaIN. The other 12 high-risk types of HPV positive may be more closely related to VAIN 1, more attention should be paid.