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Background This study was designed to compare early outcomes associated with coronary artery bypass grafting for multi-vessel disease conducted using either minimally invasive or conventional off-pump techniques. Methods From January 2017 through January 2021, 582 patients with multi-vessel lesion coronary artery disease underwent either minimally invasive cardiac surgery coronary artery bypass grafting (MICS CABG) or conventional off-pump coronary artery bypass grafting (OPCABG) treatment by our team at Anzhen Hospital. Patients in the MICS CABG group were propensity score-matched with those in the OPCABG at a 1:1 ratio (MICS CABG = 172; OPCABG = 172), using epidemiological data, preoperative clinical characteristics, and SYNTAX score as covariates. Perioperative outcomes and 6-month computed tomography angiography findings were compared between these groups. Results No significant differences between groups were observed with respect to 30-day postoperative mortality, myocardial infarction, and stroke incidence. Surgical data indicated that the MICS CABG procedure was able to cover all three main arterial territories with a relatively low need for circulatory assistance. The MICS CABG procedure was associated with a longer operative duration, but was also associated with higher postoperative hemoglobin and activities of daily living index values as well as a shorter duration of postoperative hospitalization (P Conclusions MICS CABG is a safe, less invasive alternative to OPCABG when performing complete revascularization provided patients are properly selected, yielding similar in-hospital outcomes and 6-month graft patency rates together with an earlier return of physical function.

In this paper, a chiral metamaterial (CMM) has been proposed theoretically and experimentally to realize a 90° polarization converter, whose maximum cross-polarization conversion efficiency is nearly to 1. In 0.4 GHz bandwidth around 16.8 GHz, a 90° polarization angle and negligible ellipticity can be obtained, with a minimum cross-polarization conversion efficiency of 0.96. The mechanism of the cross-polarization conversion is explained by studying the surface current and electric field of the structure. Finally, through parameter inversion, the parameter characteristics of the structure are studied.

The current global demand for novel anti-TB drugs has drawn urgent attention on the discovery of natural product compounds with anti-TB activity. Lots of efforts have emphasized on environmental samples from unexplored or underexplored natural habits and identified numerous rare actinomycete taxa producing structurally diverse bioactive natural products. Herein, we report a survey of the rare actinobacteria diversity in Xinjiang region together with the discovery of anti-TB active natural products from these strains. We have collected 17 soil samples at different sites with different environmental conditions, from which 39 rare actinobacteria were identified by using a selective isolation strategy with 5 media variations. Among those isolated strains, XJ31 was identified as a new Nocardia sp. based on 16S rRNA gene analysis. Through one strain-many compounds (OSMAC) strategy combined with anti-Bacillus Calmette-Guérin bioassay-guided isolation, two groups of compounds were identified. They were twelve siderophores (nocardimicins, 1-12) and two anthraquinones (brasiliquinones, 13 and 14) and ten of them were identified as new compounds. The structures of the purified compounds were elucidated using HR-ESI-MS, 1D NMR, and 2D NMR techniques. The anti-TB bioassays revealed that the two benz[α]anthraquinones have potent activity against BCG (MICs = 25 μM), which can be used as a promising start point for further anti-TB drug development. Key points • Ten new natural products were identified from Nocardia sp. XJ31. • Brasiliquinones 13 and 14 showed moderate anti-BCG activity. Electronic supplementary material The online version of this article (10.1007/s00253-020-10842-2) contains supplementary material, which is available to authorized users.

The current study explored the triadic relationship between the government, local\ud residents and developers as stakeholders in rural tourism land expropriation. Unstructured\ud interviews and non-participant observation were conducted to obtain relevant data. Social\ud action theory was applied to delineate the complex interaction and relationships between the\ud various stakeholders. Growth machine theory was also used to reveal the internal\ud mechanisms of these relationships. The results showed that in land expropriation for rural\ud tourism development in the case setting, stakeholders’ relationships were not merely\ud cooperative or antagonistic; rather, their interests were interwoven and showed a\ud process-based evolution with the progress of land expropriation. Finally, the local\ud government (political elite) and the developer (economic elite) formed a growth coalition and\ud jointly led the process of land expropriation. However, local residents failed to form an\ud anti-growth coalition, which indicates the potential vulnerability of tourism coalition\ud formation. These insights have implications for developing sustainable tourism, including\ud government involvement and resident participation, particularly in the context of developing\ud countries.

Accumulating evidence has shown that circular RNA (circRNA) dysregulation is involved in various types of cancer, including osteosarcoma (OS). Nevertheless, the role and mechanism of circRNAs in OS progression and chemoresistance remain elusive. We found that a novel doxorubicin-induced circular RNA, hsa_circ_0004674, screened by whole total transcriptome RNA sequencing in our previous study, was upregulated in OS chemoresistant cell lines and tissues and also connected with patients’ poor prognosis. Circ_0004674 knockdown remarkably suppressed OS cell chemoresistance, proliferation, migration, invasion, OS tumor growth, and enhanced cell cycle arrest and apoptosis in vitro and in vivo through control the expression of the antiapoptotic protein MCL1, a member of the Bcl-2 gene family. Further online bioinformatics analysis revealed that miR-142-5p had potential binding sites that can bind circ_0004674 and the 3′UTR of MCL1 mRNA. Moreover, the expression and function of miR-142-5p were conversely correlated with circ_0004674 in vitro. RIP, pull-down, luciferase assay, and RNA FISH demonstrated that circ_0004674 could compete with MCL1 for miR-142-5p binding to counteract miR-142-5p-mediated repression of MCL1 at the post-transcriptional level. To sum up, our study sheds light on the critical role of the oncogenic circ_0004674/miR-142-5p/MCL1 axis in OS progression and chemoresistance, providing a novel potential target for OS therapy.

This study describes the linkage relationships between the economic cycle and the domestic tourism cycle in Mainland China and Taiwan. The Markov-switching vector autoregressive (MS-VAR) mo...

Background: We initiated a retrospective study on ankle fractures to assess (1) the time needed for fracture union; (2) the incidence of adverse radiographic outcomes (AROs); (3) factors that might lead to AROs; and (4) whether AROs were associated with worse function and higher incidence of post-trauma osteoarthritis (PTOA). Methods: From 2007 to 2016, a total of 296 patients (169 women, 127 men; average age, 48.6 years; range, 20-84) were diagnosed with a medial malleolar fracture, whether isolated or in the setting of bi- or trimalleolar fractures, and underwent open reduction and internal fixation (ORIF) or percutaneous screw fixation (PSF). The interval to fracture union, radiographic outcomes, American Orthopaedic Foot & Ankle Society (AOFAS) score at 6 months postoperatively, and the incidence of PTOA were recorded. Risk factors were identified both in univariate and multivariate analysis. The average follow-up period was 52.0 months (range, 12-118). Results: The incidence of delayed union, nonunion, and malunion were 20.3%, 3.7%, and 4.4%, respectively. The interval to fracture union was 10.3 ± 6.4 weeks. In the multivariate analysis, the risk factors for AROs were tobacco use, vertical fractures, interposed soft tissue, and fair/poor reduction. Patients with AROs had significantly worse AOFAS score at 6 months postoperatively ( P < .001) and higher incidence of PTOA ( P < .001). Conclusion: AROs of medial malleolar fractures have an underestimated incidence rate and are associated with worse ankle function and higher incidence of PTOA. Risk factors including tobacco use, vertical fractures, interposed soft tissue, poor/fair reduction should be prudently taken into consideration when treating medial malleolar fractures. Level of Evidence: Level III, retrospective cohort study.

We initiated a retrospective study on the long-term survival of cemented endoprostheses for bone tumours around the knee to answer the following questions: (1) What was the survival of these patients? (2) What was the overall survival of cemented prostheses around the knee? (3) What types of failures were observed in these reconstructions? (4) Did the survival and complications vary according to the site of the implant? (5) What was the functional result after cemented prosthesis replacement around the knee? From January 2006 to December 2013, 108 consecutive patients with an average age of 25 years, who had mature bone development as evidenced by imaging examinations, underwent 108 cemented endoprosthetic knee replacements for osteosarcoma resection. All patients received neoadjuvant chemotherapy using a multi-drug protocol consisting of high dose methotrexate (HDMTX), doxorubicin (ADM), cisplatin (DDP) and high dose ifosfamide (HDIFO). When extensor mechanism reconstruction was required, we ran nonabsorbable sutures through designated holes in the tibial component to fix detached hamstrings and the remaining ligaments in an imbricated fashion as well as reinforced the reconstruction with a medial gastrocnemius flap. Seventy-two (72/108, 66.7%) lesions were located in the distal femur and 36 (36/108, 33.3%) lesions at the proximal tibias. Nineteen patients were staged as IIA and 89 as IIB according to the Enneking staging system. The average follow-up was 53.3 months (range 12–125 months), with a minimum oncological follow-up of one year. Survival, prosthetic failure, complications and functional outcomes were recorded and reassessed at every visit after the primary operation. At the final follow-up, the oncologic results showed that 33 patients died from metastases, and local recurrence occurred in ten patients. The estimated overall five-year and eight-year survival rates were 71% (95% CI: 62.4–79.65%) and 67.2% (95% CI: 58–76.4%), respectively. In this study, a total of 51 complications occurred in 45 patients, and at the end of follow-up, 59 patients had prostheses in situ. The estimated overall five-year and eight-year implant survival rates were 77.7% (95% CI: 67.9–87.5%) and 54.5% (95% CI: 31.4–77.6%), respectively, when patients who died with their original prostheses were censored. In total, 21 (21/108, 19.4%) implants failed, five due to infections (5/21), eight due to aseptic loosening (8/21), four due to local recurrence (4/21), three due to structural failure (3/21) and one due to soft tissue failure (1/21). The average Musculoskeletal Tumor Society Score (MSTS) at the most recent follow-up was 22.9 (9–30) points on a 30-point scale, which indicated an excellent or good functional outcome. Analysis of the results based on implant site revealed a slight difference of the estimated five-year prosthesis survival between implants located in the distal femur and those located in the proximal tibia [86.1% (95% CI: 75.5–97%) versus 66.9% (95% CI: 49.8–83.9%); P = 0.09]. However, the functional outcomes and complication rates of prostheses located in the distal femur were both better than those located in the proximal tibia. With effective management strategies for complications, cemented endoprosthetic reconstruction of the proximal tibia and distal femur using an extensor mechanism reconstruction technique provides a reliable method of reconstruction following tumour resection around the knee. Level of Evidence Level IV, therapeutic study.

Emulsions were prepared using hydroxyapatite nanoparticles and nonionic surfactant sorbitan monooleate (Span 80) as emulsifier. Effects of Span 80 concentration, emulsification time, emulsification rate, poly(l-lactic acid) (PLLA) concentration and the surface chemical properties of hydroxyapatite nanoparticles on emulsion properties were systematically studied. The results showed that emulsion would undergo a phase inversion from oil-in-water (O/W) type to water-in-oil (W/O) type with an increase in Span 80 concentration. All of the above factors are closely related to emulsion type and stability. SEM results indicated that cured materials with different structures were obtained using these emulsions as templates via in situ evaporation; especially, open-cell porous structures were obtained by a mixture of hydroxyapatite and a moderate concentration of Span 80. The mechanism of this emulsion system is proposed in relation to the emulsion properties and cured material structure, which should be attributed to the formation of hydrogen bonds between hydroxyapatite and Span 80 by hydroxyl groups as well as their location changes in the emulsion.

Recent findings have shown that lncRNA dysregulation is involved in many cancers, including osteosarcoma (OS). In a previous study, we reported a novel lncRNA, ODRUL, that could promote doxorubicin resistance in OS. We now report the function and underlying mechanism of ODRUL in regulating OS progression. We show that ODRUL is upregulated in OS tissues and cell lines and correlates with poor prognosis. ODRUL knockdown significantly inhibits OS cell proliferation, migration, invasion, and tumor growth in vitro and in vivo by decreasing matrix metalloproteinase (MMP) expression. A microarray screen combined with online database analysis showed that miR-3182 is upregulated and MMP2 is downregulated in sh-ODRUL-expressing MG63 cells and that miR-3182 harbors potential binding sites for ODRUL and the 3′ UTR of MMP2 mRNA. In addition, miR-3182 expression and function are inversely correlated with ODRUL expression in vitro and in vivo. A luciferase reporter assay demonstrated that ODRUL could directly interact with miR-3182 and upregulate MMP2 expression via its competing endogenous RNA activity on miR-3182 at the posttranscriptional level. Taken together, our study has elucidated the role of oncogenic ODRUL in OS progression and may provide a new target in OS therapy.

The surface nano-crystallization (SNC) of carbon steel was achieved via a high-speed rotating wire-brushing process. Microstructure characteristics of SNC steel were systematically studied. The SNC steel surface exhibited marked deformed plastic flows and high surface roughness. Due to the accumulated strains, a deformed gradient layer with thickness of 40–50 μm was produced, and the grain size of the topmost zone was about 50–100 nm. X-ray photoelectron spectroscopy (XPS) analysis indicated that enhanced Fe oxides and Cr oxides were generated. Electrochemical corrosion tests, including open circuit potential (OCP), electrochemical impendence spectroscopy (EIS), potentiodynamic polarization (PDP) and potentiostatic polarization (PP) were conducted to study the corrosion behavior of SNC steel in 3.5 mass% NaCl solution, where an improved corrosion resistance was observed. The resulted improvement resulted from the dominated positive effects (the attached Cr alloying element and enhanced oxide film) against the negative effects (the higher roughness and the improved corrosion activity of surface microstructure).

With the increasing degree of population aging, the traditional pension service model has been difficult to solve the problem of low matching degree between users and the supply and demand of pension service, and the transition from the traditional pension model to the wisdom endowment model is an inevitable trend. In order to improve the user acceptance of wisdom endowment application, this paper, after studying the current situation of wisdom endowment application, constructs UTAUT modification model for the user and potential user behavior of wisdom endowment application. Effective questionnaires were collected for data analysis with the help of SPSS statistical analysis software, and the AMOS structural equation model was used for empirical analysis. Finally, the paper makes a comparative analysis of the existing work, points out the future development direction of the application of wisdom endowment, and puts forward countermeasures and suggestions.

In recent years, with the continuous development of mobile communication technology and the Internet, Chinese mobile medical industry has entered an explosive development stage. The gap between medical supply and demand has brought a bright future to the mobile medical industry. From the perspective of "patient" We use UTAUT to improve the model and study the behavior of patients' mobile medical APP acceptance. Through the combination of literature research and questionnaire survey, collect relevant data and conduct empirical tests. Finally, by analyzing the main factors affecting the behavior of users using mobile medical APP and the impact, it puts forward effective suggestions and Countermeasures for the development of mobile medical APP.

Background Brucellosis is a worldwide zoonotic infectious disease that is transmitted in various ways and causes great harm to humans and animals. The brucellosis pathogen is Brucella, which mainly resides in macrophage cells and survives and replicates in host cells. However, the mechanisms underlying Brucella survival in macrophage cells have not been thoroughly elucidated to date. Peroxiredoxin 6 (Prdx6) is a bifunctional protein that shows not only GSH peroxidase activity but also phospholipase A2 activity and plays important roles in combating oxidative damage and regulating apoptosis. Results Recombinant mouse (Mus musculus) Prdx6 (MmPrdx6) was expressed and purified, and monoclonal antibodies against MmPrdx6 were prepared. Using the Brucella suis S2 strain to infect RAW264.7 murine macrophages, the level of intracellular Prdx6 expression first decreased and later increased following infection. Overexpressing Prdx6 in macrophages resulted in an increase in B. suis S2 strain levels in RAW264.7 cells, while knocking down Prdx6 reduced the S2 levels in cells. Conclusions Host Prdx6 can increase the intracellular survival of B. suis S2 strain and plays a role in Brucella infection.

A field experiment was conducted to examine the effects of plastic film mulching (PM), straw retention (SR), and planting green manure (GM) on winter wheat grain yield and soil fertility. The results showed that PM did not have consistently positive effect on the grain yield, when compared to the traditional patterns (TP). No difference of average grain yield was observed between them over three years. Soil total nitrogen (N), available phosphorus (P), potassium (K), sulfur (S), zinc (Zn) and manganese (Mn) were decreased in 20-40 cm layer in PM than those in TP, while no difference was observed for soil organic matter, nitrate (NO通过田间试验,研究地膜覆盖、秸秆还田和种植绿肥对冬小麦籽粒产量和土壤肥力的影响.结果表明: 与传统模式相比,地膜覆盖并不总能提高旱地小麦产量,3年平均产量无显著变化,但降低20～40 cm土壤全氮、有效磷、速效钾、有效硫、有效锌和有效锰含量,对土壤有机质、硝态氮、有效铁和有效铜含量无显著影响.秸秆还田的小麦产量3年平均降低12.1%,收获期0～20 cm土层全氮提高5.8%,20～40 cm土层有效铜含量提高6.2%,而有效磷和有效锰分别降低36.1%和10.2%,对开花期和收获期土壤有机质、硝态氮、速效钾、有效硫、有效锌和有效铁无显著影响.种植绿肥的籽粒产量降低12.1%,同时土壤pH、有效磷和有效硫含量降低,有机质、全氮、硝态氮、有效锌和有效锰均增加,对土壤速效钾、有效铁和有效铜均无显著影响.综上,在旱地土壤肥力较低的条件下,地膜覆盖和秸秆还田不利于土壤肥力的提升,使小麦增产受到限制;种植绿肥培肥效果最好,但应考虑区域降水情况,注意其带来的减产问题.

A novel chiral metamaterial consisting of double L resonators on two sides of the dielectric substrate is proposed in this paper. The structure can realize broadband asymmetric transmission and polarization conversion of a linearly polarized wave in the terahertz band. The polarization conversion ratio of the linearly polarized wave is more than 80% across a wide frequency range from 2.65 THz to 5.58 THz. Furthermore, the structure realizes three bands polarization angle independent 90° polarization rotator. In addition, optical activity and chirality parameter changing with frequency are studied in detail. The physical mechanism of the polarization conversion is also analyzed by the electric field distributions.

The reconstruction capability of the blue phase (BP) template with low polymer concentration was investigated. A threshold polymer concentration to reconstruct the BP with the chiral three-dimensional template was confirmed in different kinds of polymer systems. The anchoring energy of the template may reassemble the double twist cylinder structure of BP liquid crystal (BPLC) by refilling either the same-handed or reverse-handed chiral materials within a certain range of helical twisting power (HTP). Meanwhile, because of the lowered anchoring energy, the kerr constant of the reconstructed BPLC increased by 104%, from 1.81 nm/V2 to 3.70 nm/V2, by refilling the reverse-handed chiral material.

In this paper, a three-dimensional metamaterial structure absorber has been analyzed and discussed. The unit of the absorber is composed of nine different size resistive films which are placed vertically on a metal plate. The proposed metamaterial absorber can achieved the perfect absorption for different polarized waves by rotating around the center axis. The simulated results also show that the 3D absorber has the properties of extremely bandwidth, exhibiting the absorption with above 90 % for TM or TE wave from 20 to 55 GHz. In addition, the mechanism of different absorption between TE and TM mode is also discussed based on the E-field and power loss density distributions. The proposed absorber has potential application in polarization detectors, polarizer, sensor, and so on.

The development of tourism projects is often predicated on land expropriation. It is therefore important to understand residents' attitudes towards land expropriation and how changes in those attitudes can benefit both the land expropriation process and tourism development. Taking Wudaoliang in Sandaogou village in Hebei province as a case study, this study focuses on residents' attitudinal change by taking a longitudinal approach involving non-participant observation and 180 interviews. Critical event analysis was conducted, and a framework for modelling attitudinal change was adopted. The results show that the attitudes of rural residents towards tourism development were not static but underwent a dynamic process of change across three phases. These results suggest that residents should deepen their involvement in the land expropriation process and that information transparency can reduce social conflict, which will facilitate the sustainable development of rural tourism. The theoretical and practical contributions of this study are also discussed.

Chemo-resistance is a huge obstacle encountered in the osteosarcoma (OS) treatment. Protein-coding mRNAs, as well as non-coding RNAs (ncRNAs), including long ncRNA (lncRNA), circular RNA (circRNA), and microRNA (miRNA), have been demonstrated to play an essential role in the regulation of cancer biology. However, the comprehensive expression profile and competing endogenous RNA (ceRNA) regulatory network between mRNAs and ncRNAs in the OS chemo-resistance still remain unclear. In the current study, we developed whole-transcriptome sequencing (RNA sequencing [RNA-seq]) in the three paired multi-drug chemo-resistant and chemo-sensitive OS cell lines to comprehensively identify differentially expressed lncRNAs, circRNAs, miRNAs, and mRNAs. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed for mRNAs with significantly different expression. Then the ceRNA networks combining lncRNAs, circRNAs, miRNAs, and mRNAs were predicted and constructed on the basis of the authoritative miRanda and TargetScan databases combined with the widely accepted vital drug resistance-related genes and signal transduction pathways. In addition, two constructed ceRNA regulatory pathways, lncRNAMEG3/hsa-miR-200b-3p/AKT2 and hsa_circ_0001258/hsa-miR-744-3p/GSTM2, were randomly selected and validated by real-time qPCR, RNA immunoprecipitation (RIP), RNA pull-down assay, and dual luciferase reporter gene system. Taken together, our findings may provide new evidence for the underlying mechanism of OS chemo-resistance and uncover some novel targets for reversing it.

With the rapid development of Internet and smart phone technology, community e-commerce is impacting our life with irresistible trends and widely concerned. Based on the in-depth analysis of the existing problems in the development of E-commerce on Social Network, this thesis constructed a model of influencing factors of user acceptance behavior of shared community APP users. An empirical test was carried out on 757 valid questionnaires. The results showed that performance expectations, contributing factors, perceived risk and trust tendency had a significant impact on community residents' acceptance of APP products in shared communities. based on this, the countermeasures and suggestions for the development of community e-commerce are put forward.

A field experiment was conducted to examine the effects of plastic film mulching (PM), straw retention (SR) and planting green manure (GM) on grain yield and nutrient concentrations of winter wheat. Compared to the traditional pattern (TP), plastic film mulching showed no significant effect on the average yield over the three years but increased the average phosphorus (P) uptake and concentration in grain by 8.4% and 13.0%, respectively. The average uptake of nitrogen (N), sulfur (S) and iron (Fe) was decreased by 12.6%, 15.0% and 11.1%, and the corresponding concentration was decreased by 12.1%, 12.9% and 10.1%, respectively. There was no significant effect on grain zinc (Zn) concentration. Straw retention decreased grain yield by 12.1%, reduced the average uptake of N, S and Fe decreased by 22.5%, 21.0% and 19.8%, and their corresponding concentration by 10.1%, 9.4% and 3.8%, respectively. The average uptake of P in grain was decreased by 9.8% with straw retention, while the P concentration was increased by 5.0%. There was no significant effect of straw retention on Zn concentration in grain. Planting green manure decreased the grain yield by 12.1%. It had no significant effect on the average uptake of N and Zn, but increased the grain N and Zn concentration by 12.1% and 12.6%, respectively. It showed no impact on P, S and Fe concentration in grain. The discordance between variation of grain yield and its nutrient uptake under different cultivations was the key reason for the changes of their nutrient concentration. Considering the potential adverse effects of plastic film mulching and straw retention on the quantity and quality of grain yield, suitable N fertilization should be applied to ensure the nutrient requirement for grain yield and regulate the uptake and utilization of N, S and Fe for improving the grain quality. Planting green manure could improve soil fertility and increase grain N and Zn concentration, but the yield reduction deserves more attention.通过田间试验,研究地膜覆盖、秸秆还田和种植绿肥对冬小麦籽粒产量和籽粒养分含量的影响.结果表明: 与传统模式相比,地膜覆盖并不总能提高旱地小麦产量,3年平均产量无显著变化,但籽粒磷吸收量却增加8.4%,磷含量平均提高13.0%;籽粒氮、硫和铁吸收量分别降低12.6%、15.0%和11.1%,含量分别降低12.1%、12.9%和10.1%,锌含量无显著变化.秸秆还田使小麦籽粒产量下降12.1%,籽粒氮、硫和铁吸收量分别降低22.5%、21.0%和19.8%,含量分别降低10.1%、9.4%和3.8%;磷吸收量降低9.8%,含量却增加5.0%,锌含量亦无显著变化.种植绿肥的小麦籽粒产量降低12.1%,籽粒氮和锌吸收量无显著变化,含量分别增加12.1%和12.6%,对磷、硫和铁含量无显著影响.可见,旱地条件下,不同栽培模式引起的籽粒产量增减与其养分吸收量变化不一致是养分含量变化的主要原因.在旱地小麦生产中,需注意地膜覆盖和秸秆还田的减产风险及对籽粒养分的不利影响,适当调控氮肥用量,保证小麦产量形成的养分需求,协调氮、硫、铁养分的吸收利用.种植绿肥能培肥土壤,提高籽粒氮和锌含量,但也应注意其减产问题.

In this article, a new chiral metamaterial with giant optical activity (90°) around 225 and 285 THz has been proposed which can be acted as a dual-band cross polarization converter (CPC). During the frequency range of proposed CPC, the maximum transmission coefficient and cross polarization conversion efficiency are up to 0.55 and 0.998, respectively. Importantly, the corresponding ellipticities are almost zero at 225 and 285 THz.

In this paper, a novel multi-layered structure consisted of two sub-wavelength gratings and split-ring resonator printed on two sides of dielectric substrate has been proposed. This new structure can realize broadband asymmetric transmission and multi-band 90° polarization rotator in the infrared spectral region. Due to the Fabry–Perot like resonance effect, the asymmetric parameter can reach a maximum of 0.95 and over than 0.8 from 100 THz to 285 THz, which exhibit a magnitude improvement over previous optical metamaterials. The polarization conversion between two orthogonal linearly polarized waves is analyzed by the optical activity. The electric fields are also investigated and the simulated results are coinciding with the calculated ones.

As a newly developed engineering structure, bucket foundation breakwater is adapted to soft soil. In this paper, the general-purpose finite element analysis package ABAQUS is employed to conduct three-dimensional numerical analyses on bucket foundation breakwater. Then earth pressure variation on bucket foundation is carried out under different loads of horizontal displacement. Through analysis it obtains the laws of the earth pressure on the meeting-wave side and the back-wave side of bucket foundation breakwater. This will provide the reference and the evidence of preliminary theory for the stability research and practical engineering application of bucket foundation breakwater.

In this paper, a three-layered chiral structure with double L resonators on both sides of dielectric substrate is proposed, which can realize asymmetric transmission of linearly polarized wave in near-infrared band. The asymmetric transmission parameter of linearly polarized wave can reach a maximum of 0.9. Due to non-C4 symmetry of the structure, we introduce Stokes parameters to describe the polarization state of the wave. The physical mechanism of asymmetric transmission and hybridized plasmon mode is also analyzed in detail.

In this paper, a chiral metamaterial that consists of two complementary U-shaped structures on both sides of a substrate is proposed, which achieves dual-band asymmetric transmission effect of linearly polarized wave at 0.88 and 1.03 THz bands. The asymmetric transmission effect and resonance frequency can be adjusted through changing structure parameters. The physical mechanisms of dual-band asymmetric transmission are also analyzed based on different couple modes excited at resonant frequency.

The anchoring energy of blue phase polymer template containing different concentration of conventional polymer has been studied. The lower bound of polymer concentration to form the chiral three-dimensional template of blue phase is confirmed. And it was demonstrated that the template anchoring energy has a threshold value to reassemble the double twist cylinder structure of blue phase liquid crystal by either refilling same-handed chiral materials or reverse-handed chiral materials which may help to improve the driving capacity of the polymer stabilized blue phase liquid crystal.

With the development of mobile social networking platform and Internet advertising, the problems like that flush spam and lower user acceptance have gradually emerged. Based on the research of references about mobile social advertising and user adoption and some others, the paper constructs a model of mobile social platform advertising user adoption based on UTAUT. We use the SPSS and AMOS software to analyze the questionnaire and interviews data, and the model was tested empirically. The results show that among those 15 users’ acceptance models, 13 of them embrace hypothetically tenable relationships between the model variables. Those 13 models can provide optimized solutions and the suggestion of creative show forms for mobile advertisement providers.