With the Internet and AI technology development, piano education in colleges and universities faces innovative challenges. This study explores the effectiveness of the Internet-based teaching mode in ...enhancing students’ music appreciation ability. The study adopts a teaching model based on the Internet and AI technology, combining automatic composition, arranging and piano concerto repertoire sessions, and AI+professional teachers’ collaborative evaluation. By implementing a creative thinking teaching module, including pre-course preparation, classroom training and presentation, and post-course communication, the study aimed to improve students’ music appreciation and creative thinking skills. The study results showed that students demonstrated significant improvement in music appreciation skills. The data showed that students who participated in the new teaching model showed an average of 25% improvement in music appreciation skills assessment. In addition, students’ creative thinking skills were also enhanced, with 85% of them demonstrating a high level of innovative music composition. The college piano education model integrating Internet and AI technologies significantly improves students’ music appreciation ability and creative thinking. This model enhances the interactivity and fun of teaching, provides students with a broader platform for musical understanding and practice, and offers new perspectives and methods for music education in colleges and universities.
•We analyzed change trends of the climate variables ET0 and AI in an arid region of China over the past 50years.•We identified the sensitivity of ET0 and AI to the main climate variables.•We ...quantified the contributions of climate variables to the changes in ET0 and AI.•Contribution of wind speed decline to decrease of ET0 is larger than other climate variables.•The increase of precipitation contributes more than the decrease of ET0 to decrease of AI.
Temporal variations in reference evapotranspiration (ET0) and aridity index (AI) were comprehensively investigated for 23 meteorological stations during 1955–2008 in the northwest China. The quantitative contributions of the major meteorological variables to the ET0 and AI trends were evaluated and the possible causes were also investigated. The results showed that in the past 50years annual temperature, humidity and precipitation had significant increasing trends with time, and wind speed and radiation had decreasing trends. ET0 had a significant decreasing trend with an averagely value of about 3mm per year, and AI had also witnessed a decreasing trend; For ET0, wind speed was the most sensitive meteorological variable, followed by relative humidity, temperature and radiation and for AI, precipitation was the most sensitive meteorological variable. The contribution of wind speed to the decrease of ET0 is more than that of other meteorological variables. The increase of precipitation contributes more than the decrease of ET0 to decrease of AI in past 50years. This study provides an understanding of the effect of recent climate change on drought in arid northwest China.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Fine roots of woody plants comprise multiple root orders, which can be functionally partitioned into two pools: absorptive fine roots (AFRs, orders 1, 2) and transport fine roots (TFRs, orders 3–5). ...However, the function-based fine-root dynamics and especially their responses to increased nitrogen (N) availability remain unclear.
We explored dynamic responses of both AFRs and TFRs of Pinus elliottii to N addition in subtropical China based on a 4-yr minirhizotron experiment and a two-stage – early (0.5 yr) vs late (4 yr) – decomposition experiment.
N addition increased the production, mortality, and turnover of AFRs but not TFRs. High rates of N persistently inhibited AFR decomposition but affected TFR decomposition differentially at the early (no effect) and late (negative effect) stages. The increased production of AFRs was driven by N-induced decrease in foliar and soil phosphorus (P) concentrations. The decreased decomposition of AFRs might be due to the increased acid-unhydrolyzable residues in decomposing roots.
AFRs are the resource-acquiring module, the increased carbon allocation to AFRs may represent
a P-acquiring strategy when N no longer limits growth of P. elliottii. Our results suggest that AFRs and TFRs respond differently to N deposition, both in terms of production, mortality, and turnover and in terms of decomposition.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Appropriate fertilizer application is an important management practice to improve soil fertility and quality in the red soil regions of China. In the present study, we examined the effects of five ...fertilization treatments these were: no fertilizer (CK), rice straw return (SR), chemical fertilizer (NPK), organic manure (OM) and green manure (GM) on soil pH, soil organic carbon (SOC), total nitrogen (TN), C/N ratio and available nutrients (AN, AP and AK) contents in the plowed layer (0-20 cm) of paddy soil from 1998 to 2009 in Jiangxi Province, southern China. Results showed that the soil pH was the lowest with an average of 5.33 units in CK and was significantly higher in NPK (5.89 units) and OM (5.63 units) treatments (P<0.05). The application of fertilizers have remarkably improved SOC and TN values compared with the CK, Specifically, the OM treatment resulted in the highest SOC and TN concentrations (72.5% and 51.2% higher than CK) and NPK treatment increased the SOC and TN contents by 22.0% and 17.8% compared with CK. The average amounts of C/N ratio ranged from 9.66 to 10.98 in different treatments, and reached the highest in OM treatment (P<0.05). During the experimental period, the average AN and AP contents were highest in OM treatment (about 1.6 and 29.6 times of that in the CK, respectively) and second highest in NPK treatment (about 1.2 and 20.3 times of that in the CK). Unlike AN and AP, the highest value of AK content was observed in NPK treatments with 38.10 mg·kg(-1). Thus, these indicated that organic manure should be recommended to improve soil fertility in this region and K fertilizer should be simultaneously applied considering the soil K contents. Considering the long-term fertilizer efficiency, our results also suggest that annual straw returning application could improve soil fertility in this trial region.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Plant species diversity affects carbon and nutrient cycling during litter decomposition, yet the generality of the direction of this effect and its magnitude remains uncertain. With a meta-analysis ...including 65 field studies across the Earth's major forest ecosystems, we show here that decomposition was faster when litter was composed of more than one species. These positive biodiversity effects were mostly driven by temperate forests but were more variable in other forests. Litter mixture effects emerged most strongly in early decomposition stages and were related to divergence in litter quality. Litter diversity also accelerated nitrogen, but not phosphorus release, potentially indicating a decoupling of nitrogen and phosphorus cycling and perhaps a shift in ecosystem nutrient limitation with changing biodiversity. Our findings demonstrate the importance of litter diversity effects for carbon and nutrient dynamics during decomposition, and show how these effects vary with litter traits, decomposer complexity and forest characteristics.
Increase of anthropogenic atmospheric nitrogen (N) deposition markedly influences biogeochemical cycles of elements in a wide range of ecosystems. However, our knowledge of how N deposition affects ...stoichiometry of plants in forests experiencing regular seasonal droughts remains limited. Using a 3-year (2013–2015) N-manipulative experiment, we examined the stoichiometric responses of ten mineral elements, including the most limiting elements (N and P) to plant growth, base cations (K, Ca, and Mg), and trace metal cations (Mn, Zn, Cu, Al, and Fe) in resource-acquiring organs (foliage vs. absorptive roots) of Pinus elliottii to N additions in both wet and dry seasons in a seasonally dry subtropical forest. Stoichiometric responses of both organs depended on rate of N addition (generally stronger under high rate) and season. N additions increased foliar N and decreased foliar P only in dry season and the relative changes in foliar N:P ratio were twice higher in dry than wet seasons, suggesting an aggravated P limitation in dry season. The stoichiometry of absorptive roots was more responsive to N additions than that of foliage, especially for the base cations. N additions increased Mn and decreased Fe:Mn ratio in both organs, indicating increased risk of Mn2+ toxicity to this tree species. Our results have implications for understanding the N-induced changes in nutrient limitation of forests influenced by seasonal drought, and highlight the contrasting stoichiometric responses of above- and below-ground resource-acquiring plant organs to N loading.
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•Stoichiometric responses of foliage and absorptive roots depend on rate of N added.•Seasonal drought mediates N effects on stoichiometry depending on element and organ.•Effect of N addition on P limitation is intensified in dry season.•Base cations respond more strongly in absorptive roots than in foliage in wet season.•N addition increases Mn concentration and decreases Fe:Mn ratio in both organs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Groundwater resources strongly support crop water requirement and economic yield improvement in semi-arid and arid areas. Water resources management require more investigation in the response of ...evapotranspiration (ET) partitioning and water use efficiency to groundwater change. Observational data collected over a three-year period, including water and carbon flux, vegetable sap flow, meteorological factors, soil water content, and groundwater depth, were employed in this study. Additionally, an improved Shuttleworth-Wallace model was used for partitioning plant transpiration and bare soil evaporation (E) in a sunflower cropland with shallow groundwater. The ET of the sunflower was founded to be 353.5 ± 15.0 mm, and approximately 48.3 ± 7.4% derived from the groundwater evaporation. E amounted approximately 145.6 ± 6.1 mm over the growth season, and around 47.2% of which was lost during the seeding stage. Furthermore, its dynamics depended on crop growth and groundwater table depth (WTD). These large amounts of non-productive soil E had a negative impact on the water-carbon coupling. The presence of E had resulted in a lower ecosystem water use efficiency (WUEe), measured at 1.02 ± 0.33 g C kg−1 H2O, compared to canopy water use efficiency (WUEc) of 1.68 ± 0.41 g C kg−1 H2O. These results demonstrated that regulating WTD could improve WUEe by increasing WUEc and reducing soil E. To achieve the higher WUEe, an optimum WTD was range of 1.5–2.0 m for border-irrigated sunflower field grown on sandy loam, identified by an analysis of normalized evaporation difference at the varying WTD. This finding highlights the significance of maintaining specified WTD, providing valuable insights into the complex interplay between crop evapotranspiration components and shallow groundwater. Moreover, it offers guidance for precision agriculture irrigation practices.
•Observation data and improved Shuttleworth-Wallace model were used for evapotranspiration partition.•Regulating groundwater within a certain range can improve water use efficiency by reducing non-productive soil evaporation.•The optimum groundwater table depth for sunflower was determined as about 1.5–2.0 m.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In order to investigate the microstructure characteristics and properties of Ni-based WC composite coatings containing a relatively large amount of WC particles by laser induction hybrid rapid ...cladding (LIHRC) and compare to the individual laser cladding without preheating, Ni60A
+
35
wt.% WC composite coatings are deposited on A3 steel plates by LIHRC and the individual laser cladding without preheating. The composite coating produced by the individual laser cladding without preheating exhibits many cracks and pores, while the smooth composite coating without cracks and pores is obtained by LIHRC. Moreover, the cast WC particles take on the similar dissolution characteristics in Ni60A
+
35
wt.% WC composite coatings by LIHRC and the individual laser cladding without preheating. Namely, the completely dissolved WC particles interact with Ni-based alloy solvent to precipitate the blocky and herringbone carbides, while the partially dissolved WC particles still preserve the primary lamellar eutectic structure. A few WC particles are split at the interface of WC and W
2C, and then interact with Ni-based alloy solvent to precipitate the lamellar carbides. Compared with the individual laser cladding without preheating, LIHRC has the relatively lower temperature gradient and the relatively higher laser scanning speed. Therefore, LIHRC can produce the crack-free composite coating with relatively higher microhardness and relatively more homogeneous distribution of WC particles and is successfully applied to strengthen the corrugated roller, showing that LIHRC process has a higher efficiency and good cladding quality.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The carck-free Fe-based +20
wt% WC coating with large area was produced by mutli-track overlapping laser induction hybrid rapid cladding. The results showed that the maximum laser scanning speed and ...the maximum feeding rate of powder can be increased to 3500
mm/min and 120
g/min, respectively. The cast WC particles were dissolved almost completely and had a worse wettability with Fe-based metal matrix. The precipitated carbides such as M
12C and M
23C
6 (M=Fe, W, Cr) formed an intergranular network around the primary Fe-based phase enriched with tungsten. The microhardness of coating decreased first, and then increased slightly with an increase in the track. The first track had the highest microhardness (i.e. 870HV
0.2). Moreover, the wear weight of coating approximately had a linear relationship with the sliding distance, and increased with an increase in the sliding speed. The wear rate approximately remained constant with an increase in the sliding distance and was two times lower than that of the hardened steel AISI 1045 with a hardness of 60HRC. The wear mechanism during the dry sliding wear was a combination of oxidation wear and abrasion wear.
► The laser scanning speed can be increased to 3500
mm/min. ► The maximum feeding of powder can be increased to 120
g/min. ► WC had a relatively worse wettability with Fe-based metal matrix. ► The microhardness of coating decreased first, then increased with the track. ► The wear mechanism of coating was a combination of oxidation wear and abrasion wear.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
As a pathological coagulation process, thrombus can lead to many serious diseases, including ischemic stroke, acute myocardial infarction (AMI), acute coronary syndrome (ACS), and deep venous ...thrombosis (DVT). And anticoagulant drugs are one of the most effective ways to prevent and treat these diseases. Although macromolecular anticoagulant drugs such as low molecular weight heparins (LMWHs) are widely used in the clinic, their characteristics of requiring injectable use hinder their further promotion in the clinic, and the disadvantages of oral anticoagulant drugs, such as warfarin and dabigatran etexilate, which can easily cause bleeding adverse effects, are also not addressed. Factor Xa (FXa) has gained attention because it lies at the intersection of the coagulation cascade pathways, whereas subsequently introduced Factor Xa inhibitors such as rivaroxaban and apixaban, among others, have gained market popularity because of their high potency for anticoagulation and high specificity for Factor Xa when administered orally. But some of the drawbacks that these Factor Xa inhibitors have simultaneously such as fewer indications and the lack of an effective reversal drug when bleeding occurs are urgently addressed. The development of new Factor Xa inhibitors therefore becomes one means of addressing these questions. This article summarizes the small molecule Factor Xainhibitors developed from 2015 to 2022, classifies them according to their scaffolds, focuses on the analysis of their structure-activity relationships, and provides a brief assessment of them.
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