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The determination of threshold and the construction of thresholding function would directly affect the signal denoising quality in wavelet transform denoising techniques. However, some deficiencies exist in the conventional methods, such as fixed threshold value and the inflexible thresholding functions. To overcome the defects of the traditional wavelet thresholding techniques, a modified particle swarm optimization (MPSO) algorithm-based parametric wavelet thresholding approach is proposed for signal denoising. Firstly, a kind of parametric wavelet thresholding function construction method is proposed on the basis of conventional thresholding functions. With mathematical derivation, the properties of the constructed function are proved. Three dynamic adjustment strategies are then employed to modify the PSO algorithm. The mean square error (MSE) between the original signal and the reconstructed signal is minimized by the MPSO algorithm. Finally, the performances of the proposed approach and the existing methods are simulated by denoising four benchmark signals with different noise levels. The simulation results show that the proposed MPSO-based parametric wavelet thresholding can obtain lower MSE, higher signal-to-noise ratio, and noise suppression ratio compared to the other algorithms. Besides, the denoising visual results also indicate the superiority of the proposed approach in terms of the signal denoising capability. [ABSTRACT FROM AUTHOR]

Improper irrigation by Panax notoginseng growers can lead to soil consolidation, low fertilizer utilization, and decreased yield quality. In an attempt to provide a scientific and theoretical basis for Panax notoginseng cultivation to improve soil microhabitat and yield quality, field experiment were conducted on three-year-old Panax notoginseng in 2019, 2020, and 2021. The experimental design consisted of two control factors, the amount of irrigation (W) and the amount of fertilizer (F) applied. The irrigation was set to three levels, as W1, W2, and W3, with exact irrigation volumes of 5 mm, 10 mm, and 15 mm. The amount of fertilizer applied was different in all four growth stages. The amount of fertilizer applied according to the four growth stages (rooting stage: seedling stage: flowering stage: fruiting stage), where F1 (360–360–360–360 kg∙hm−2), F2 (288–360–432–360 kg∙hm−2), F3 (216–432–432–360 kg∙hm−2) and F4 (144–576–288–432 kg∙hm−2). The W and F were randomly combined to form a total of 12 treatments. And a control treatment (CK), was added, and CK was neither irrigated nor fertilization. For obtaining the best treatment results, the TOPSIS method was used to comprehensively evaluate the soil microbial biomass carbon and nitrogen, enzyme activity, physiological growth and saponin content of Panax notoginseng in 13 different water and fertilizer treatments. The results indicated that microbial biomass carbon and nitrogen, urease, sucrase, acid phosphatase and catalase activities of Panax notoginseng soil were significantly different (P < 0.05) and varied with the growth stage. The comprehensive evaluation by the TOPSIS method ranked W3F4 first and was the optimal treatment. The W3F4 treatment was more beneficial to the quality of Panax notoginseng than the other 12 treatments. W3F4 had the largest soil microbial biomass carbon and nitrogen content. W3F4 had the highest urease, sucrase, acid phosphatase, and catalase activities, which were 1.95, 1.69, 2.32, and 1.47 times higher than the CK treatment, respectively. W3F4 significantly improved R 1 , Rg 1 , Re, Rb 1 , and Rd saponin content. This study provided a theoretical basis for the water and fertilizer regulation of Panax notoginseng with its green, healthy and efficient quality cultivation. • W3F4 treatment was most beneficial for the increase of ginsenoside content. • Soil microbial biomass C and N were negatively associated with Re, and were positively associated with R 1. • Soil water content, sucrase, acid phosphatase, catalase, and urease were negatively correlated with Rb 1. [ABSTRACT FROM AUTHOR]

Water and fertilizer are two important factors affecting crop growth and yield. Crop growth models are powerful tools for making irrigation and fertilization scheduling and predicting crop yield. The performance of crop models on potato under different irrigation amounts along with different N, P and K rates has been rarely evaluated, especially under drip fertigation. In this study, the accuracy of AquaCrop and DSSAT-SUBSTOR-Potato models in simulating potato growth, yield and water productivity under different drip fertigation regimes was compared. For model calibration and validation, a two-year field experiment with three irrigation levels (W 1 , 60% ET C ; W 2 , 80% ET C and W 3 , 100% ET C , where ET C was the crop evapotranspiration) and four fertigation (N-P 2 O 5 -K 2 O) rates (F 1 : 100–40–150 kg ha−1, F 2 : 150–60–225 kg ha−1, F 3 : 200–80–300 kg ha−1 and F 4 : 250–100–375 kg ha−1) was carried out in a sandy region of northwest China in 2018 and 2019. The statistical indicators showed that the AquaCrop model gave satisfactory predictions of canopy cover (R 2 ≥ 0.92, NRMSE ≤ 14.7%, d ≥ 0.96 and RMSE ≤ 10.8%), total dry matter (R 2 ≥ 0.92, NRMSE ≤ 25.0%, d ≥ 0.94 and RMSE ≤ 2.2 t ha−1), final dry tuber yield (R 2 ≥ 0.57, NRMSE ≤ 12.21%, d ≥ 0.82 and RMSE ≤ 0.83 t ha−1) and fresh tuber yield (R 2 ≥ 0.53, NRMSE ≤ 12.02%, d ≥ 0.81 and RMSE ≤ 4.91 t ha−1) in the four fertigation treatments (F 1 -F 4) under W 3 and W 2 during the two potato growing seasons. The final total dry matter and tuber yield under W 1 were over-estimated. The simulated water productivity and soil water content also agreed well with the observations (R 2 ≥ 0.91 , NRMSE ≤ 5.51%, d ≥ 0.94 and RMSE ≤ 0.48 kg m−3, and R 2 ≥ 0.40 , NRMSE ≤ 14.8%, d ≥ 0.77 and RMSE ≤ 11.5 mm). The simulation accuracy of DSSAT-SUBSTOR-Potato model was lower than that of AquaCrop model, which only showed a goodness of fit between simulated total dry matter, soil water content, tuber yield, water productivity and observations under high irrigation amount with high fertilization rate (W 3 F 4). Since the observed tuber yield increased with the increase of irrigation level (60–100% ET C) under the same fertigation rate, 120%ET C and 40%ET C were further simulated using the AquaCrop model to test the changes in tuber yield with further increased or decreased irrigation levels. The scenarios simulation showed that the tuber yield was only increased by 0.19%−1.52% under 120%ET C compared with that under 100% ET C , but 18.0% more irrigation water was consumed. Comprehensively considering water resources and tuber yield, the irrigation level of 100% ET C (W 3) along with fertigation (N-P 2 O 5 -K 2 O) rate of 200–80–300 kg ha−1 (F 3) was recommended for the sustainable potato production in the study region. The results of this study can provide guidance for the application of crop models in drip-fertigated potato. • AquaCrop and DSSAT-SUBSTOR-Potato were evaluated under various drip fertigation regimes. • AquaCrop adequately simulated the effects of irrigation and fertilization regimes on potato. • Simulation accuracy of DSSAT-SUBSTOR-potato was lower than that of AquaCrop. • 100% ET C along with N-P 2 O 5 -K 2 O rate of 200–80–300 kg ha−1 was recommenced for potato production. [ABSTRACT FROM AUTHOR]

• A novel (octylamine modified vermiculite) material for enhanced simultaneous removal of Cd(II) and Pb(II). • Modification involved ion exchange and surface complexation properties between surfactant and vermiculite. • Modified material was low lost with no secondary pollution. • After modification, adsorbent showed >220 % metal uptake with easy separation and recyclability. Cadmium (Cd) and lead (Pb) have been remained the topic of investigation for various research studies because of their adverse effects on human health, furthermore, they have toxic and non‒biodegradable properties. In this study, vermiculite (VER) was functionalized with octylamine (OCT) to obtain a novel organoclay (OCT-VER) for enhanced simultaneous adsorption of Cd(II) and Pb(II) from aqueous solution. Adsorbents were characterized and parameters influencing on adsorption were also investigated. The adsorption of Cd(II) and Pb(II) by OCT-VER was monolayer and homogenous which was described well by Langmuir isotherm model. After modification, the affinities of OCT-VER towards both metal ions were enhanced. In single system, maximum adsorption capacities for Cd(II) and Pb(II) were improved from 45.245 and 102.289 mg.g−1 to 69.595 and 184.603 mg.g−1, while in binary system from 37.539 and 78.265 mg.g−1 to 61.630 and 121.986 mg.g−1, respectively. In adsorbent regeneration experiment of OCT-VER, the removal ratio was found ≈90 % even after 5 consecutive cycles, exhibiting good stability and easy regeneration potential. After studying thoroughly, ion-exchange and complexation properties were the main reaction mechanism. These findings suggested that the proposed low cost adsorbent was suitable and promising material for Cd(II) and Pb(II) adsorption in water. [ABSTRACT FROM AUTHOR]

Amphiphilic aromatic poly (amino acids) polymers were designed as biodegradability demulsifiers with higher aromaticity, stronger polarity, and side chain-like combs. The effects of demulsifier dosage, structural characteristics and emulsion properties such as pH, salinity, and oil content on the demulsification efficiency were investigated. The results show that the poly (L-glutamic-benzyl ester)-block-poly (L-phenylalanine) (PBLG 15 -b-PPA 15 ) as the demulsifier can remove more than 99.97% of the oil in a 5.0 wt% oil-in-water (O/W) emulsion at room temperature within 2 min. The poly (L-tyrosine)-block-poly (L-phenylalanine) (PTyr 15 -b-PPA 15 ) with environmental durability demonstrates high effectiveness, universality, and demulsification speed. It achieves a remarkable demulsification efficiency of up to 99.99% for a 20.0 wt% O/W emulsion at room temperature. The demulsification mechanism indicates that demulsifiers have sufficient interfacial activity can quickly migrate to the oil-water interface after being added to the emulsions. Additionally, when demulsifiers are present in a continuous phase in the molecular form, their "teeth" side chains are beneficial for increasing coalescence and flocculation capacities. Furthermore, according to the Density Functional Theory (DFT) calculations, enhancing the intermolecular interactions between demulsifiers and the primary native surfactants that form an oil-water interfacial film is a more efficient approach to reducing demulsification temperature and improving demulsification efficiency and rate., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In the continuous cropping of Panax notoginseng , the pathogenic fungi in the rhizosphere soil increased and infected the roots of Panax notoginseng , resulting in a decrease in yield. This is an urgent problem that needs to be solved in order to effectively overcome the obstacles associated with the continuous cropping of Panax notoginseng . Previous studies have shown that Bacillus subtilis inhibits pathogenic fungi in the rhizosphere of Panax notoginseng , but the inhibitory effect was not stable. Therefore, we hope to introduce biochar to help Bacillus subtilis colonize in soil. In the experiment, fields planted with Panax notoginseng for 5 years were renovated, and biochar was mixed in at the same time. The applied amount of biochar was set to four levels (B0, 10 kg·hm -2 ; B1, 80 kg·hm -2 ; B2, 110 kg·hm -2 ; B3, 140 kg·hm -2 ), and Bacillus subtilis biological agent was set to three levels (C1, 10 kg·hm -2 ; C2, 15 kg·hm -2 ; C3, 25 kg·hm -2 ). The full combination experiment and a blank control group (CK) were used. The experimental results show that the overall Ascomycota decreased by 0.86%~65.68% at the phylum level. Basidiomycota increased by -73.81%~138.47%, and Mortierellomycota increased by -51.27%~403.20%. At the genus level, Mortierella increased by -10.29%~855.44%, Fusarium decreased by 35.02%~86.79%, and Ilyonectria increased by -93.60%~680.62%. Fusarium mainly causes acute bacterial wilt root rot, while Ilyonectria mainly causes yellow rot. Under different treatments, the Shannon index increased by -6.77%~62.18%, the Chao1 index increased by -12.07%~95.77%, the Simpson index increased by -7.31%~14.98%, and the ACE index increased by -11.75%~96.12%. The good&#95;coverage indices were all above 0.99. The results of a random forest analysis indicated that Ilyonectria , Pyrenochaeta , and Xenopolyscytalum were the top three most important species in the soil, with MeanDecreaseGini values of 2.70, 2.50, and 2.45, respectively. Fusarium , the primary pathogen of Panax notoginseng , ranked fifth, and its MeanDecreaseGini value was 2.28. The experimental results showed that the B2C2 treatment had the best inhibitory effect on Fusarium , and the relative abundance of Fusarium in Panax notoginseng rhizosphere soil decreased by 86.79% under B2C2 treatment; the B1C2 treatment had the best inhibitory effect on Ilyonectria , and the relative abundance of Ilyonectria in the Panax notoginseng rhizosphere soil decreased by 93.60% under B1C2 treatment. Therefore, if we want to improve the soil with acute Ralstonia solanacearum root rot, we should use the B2C2 treatment to improve the soil environment; if we want to improve the soil with yellow rot disease, we should use the B1C2 treatment to improve the soil environment.

The acoustic diffusion equation model has been widely applied in various scenarios, but a larger prediction error exists when applied to underground spaces, showing a significantly lower characteristic of the sound pressure level in the later stage compared to field tests since underground spaces have a more closed acoustic environment. Therefore, we analyze the characteristics of underground spaces differentiating from aboveground spaces when applying the model and propose an improved model from the perspective of energy balance. The energy neglected in the calculation of the acoustic diffusion equation model is compensated in long channel underground spaces named "acoustic escape compensation". A simulation and two field experiments are conducted to verify the effectiveness of the proposed compensation strategy in long-channel underground spaces. The mean square error is used to evaluate the differences between the classical model and the improved model, which shows a numerical improvement of 1.3 in the underground field test. The results show that the improved model is more suitable for describing underground spaces. The proposed strategy provides an effective extension of the acoustic diffusion equation model to solve the problem of sound field prediction and management in underground spaces.

This study evaluated the effects of hot air drying (HAD), microwave drying (MD), vacuum drying (VD), sun drying (SD) and vacuum freeze drying (VFD) on the physical properties, bioactive components, antioxidant capacity, volatile components and industrial application of coffee peel. The results showed VFD could retain the appearance color, total phenolics (19.49 mg GAE/g DW), total flavonoids (9.65 mg CE/g DW), caffeine (3.15 mg/g DW), trigonelline (2.71 mg/g DW), and antioxidant capacities of fresh sample to the greatest extent, but its operating cost was significantly higher than other treatments and total volatile components were in the minimum levels. HAD and SD exhibited the highest loss rates of total phenols and antioxidant capacities, exceeding 50%. MD offered the lowest operating cost, superior retention of bioactive components, and the richest variety and quantity of volatile compounds. Therefore, it is recommended to use MD to dehydrate the coffee peel in actual production., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Author(s).)

Persistent free radicals (PFRs) in biochar can influence biochar reactivity, promoting organic contaminant degradation or even causing certain toxic impacts. However, the PFR generation mechanism is not still well understood. An investigation of the relationship between PFR formation and the chemical structure of biochar is essential for understanding the PFR formation mechanism. Our in situ measurement results showed that PFR intensities increased from 0-509.5 to 146-5678 a.u. after being pyrolyzed at 300 °C for 60 min. The significant positive correlation between PFR intensities and the peak areas of C═O and aromatic C═C groups indicated that the generation of PFRs was highly dependent on the C═O and aromatic C═C structures. The reduction of biochars by KBH 4 resulted in a 32.2 ± 2.49% decrease in the C═O content and a relative increase in the C-O content, while other physicochemical properties did not change. Thus, the observed 49.3% decrease in PFR signals after this reduction suggested that the reducible C═O groups, possibly in aldehydes, aromatic ketones, and quinones, were closely associated with PFRs in biochars. This study provides an in situ insight into the PFR generation mechanism and guides the corresponding biochar design and property manipulation.

To obtain optimal irrigation management for young coffee tree, the effects of alternate drip irrigation (ADI) and superabsorbent polymers on physiology, growth, dry mass accumulation and water use on one-year old Coffea arabica L. tree were investigated. This experiment had three drip irrigation methods, i.e., conventional drip irrigation (CDI), alternate drip irrigation (ADI) and fixed drip irrigation (FDI), and two levels of superabsorbent polymers, i.e., no superabsorbent polymers (NSAP) and added superabsorbent polymers (SAP). Compared to CDI, ADI saved irrigation water by 32.1% and increased water use efficiency (WUE) by 29.9%. SAP increased root-shoot ratio, total dry mass and WUE by 20.3, 24.9 and 33.0%, respectively, when compared to NSAP. Compared to CDI with NSAP treatment, ADI with SAP treatment increased total dry mass by 13.8% and saved irrigation water by 34.4%, thus increased WUE by 73.4%, and it increased root activity, the contents of chlorophyll and soluble sugar in leaves by 162.4, 38.0 and 8.5%, but reduced the contents of proline and malondialdehyde in leaves by 7.2 and 9.7%, respectively. Thus, alternate drip irrigation with superabsorbent polymers increased the growth and WUE of young Coffea arabica L. tree and was optimal irrigation management for young coffee tree.