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Polyploidy is a prominent mechanism of plant speciation and adaptation, yet the mechanistic understandings of duplicated gene regulation remain elusive. Chromatin structure dynamics are suggested to govern gene regulatory control. Here, we characterized genome-wide nucleosome organization and chromatin accessibility in allotetraploid cotton, Gossypium hirsutum (AADD, 2n = 4X = 52), relative to its two diploid parents (AA or DD genome) and their synthetic diploid hybrid (AD), using DNS-seq. The larger A-genome exhibited wider average nucleosome spacing in diploids, and this intergenomic difference diminished in the allopolyploid but not hybrid. Allopolyploidization also exhibited increased accessibility at promoters genome-wide and synchronized cis-regulatory motifs between subgenomes. A prominent cis-acting control was inferred for chromatin dynamics and demonstrated by transposable element removal from promoters. Linking accessibility to gene expression patterns, we found distinct regulatory effects for hybridization and later allopolyploid stages, including nuanced establishment of homoeolog expression bias and expression level dominance. Histone gene expression and nucleosome organization are coordinated through chromatin accessibility. Our study demonstrates the capability to track high-resolution chromatin structure dynamics and reveals their role in the evolution of cis-regulatory landscapes and duplicate gene expression in polyploids, illuminating regulatory ties to subgenomic asymmetry and dominance.
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Cromatina , Diploide , Evolução Molecular , Gossypium , Poliploidia , Gossypium/genética , Cromatina/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Nucleossomos/genética , Genes Duplicados , Regiões Promotoras GenéticasRESUMO
High-entropy ceramics exhibit various excellent properties owing to their high configurational entropy, which is caused by multi-principal elements sharing one lattice site. The configurational entropy will further increase significantly if multi-principal elements randomly share two different lattice sites. For this purpose, pseudobrookite phase containing two cationic lattice sites (A and B sites) is selected, and corresponding high-entropy pseudobrookite (M2+ 0.4M3+ 1.2)Ti1.4O5 is synthesized. Herein, the distribution of the 2-valent and 3-valent cations in the A and B sites are analysed in depth. The distance between the A and B sites in the crystal structure models which are constructed by the Rietveld analysis is calculated and defined as distance d. Meanwhile, the atomic column positions in the STEM images are quantified by a model-based mathematical algorithm, and the corresponding distance d are calculated. By comparing the distance d, it is determine that the 2-valent and 3-valent cations are jointly and disorderly distributed in the A and B sites in high-entropy (M2+ 0.4M3+ 1.2)Ti1.4O5. The density functional theory (DFT) simulations also demonstrate that this type of crystal structure is more thermodynamically stable. The higher degree of cationic disorder leads to a higher configurational entropy in high-entropy (M2+ 0.4M3+ 1.2)Ti1.4O5, and endows high-entropy (M2+ 0.4M3+ 1.2)Ti1.4O5 with very low thermal conductivity (1.187-1.249 W m-1 K-1).
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Understanding the reconstruction mechanism to rationally design cost-effective electrocatalysts for oxygen evolution reaction (OER) is still challenging. Herein, a defect-rich NiMoO4 precatalyst is used to explore its OER activity and reconstruction mechanism. In situ generated oxygen vacancies, distorted lattices, and edge dislocations expedite the deep reconstruction of NiMoO4 to form polycrystalline Ni (oxy)hydroxides for alkaline oxygen evolution. It only needs ≈230 and ≈285 mV to reach 10 and 100 mA cm-2, respectively. The reconstruction boosted by the redox of Ni is confirmed experimentally by sectionalized cyclic voltammetry activations at different specified potential ranges combined with ex situ characterization techniques. Subsequently, the reconstruction route is presented based on the acid-base electronic theory. Accordingly, the dominant contribution of the adsorbate evolution mechanism to reconstruction during oxygen evolution is revealed. This work develops a novel route to synthesize defect-rich materials and provides new tactics to investigate the reconstruction.
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Structured illumination microscopy (SIM) is a powerful technique for super-resolution (SR) image reconstruction. However, conventional SIM methods require high-contrast illumination patterns, which necessitate precision optics and highly stable light sources. To overcome these challenges, we propose a new method called contrast-robust structured illumination microscopy (CR-SIM). CR-SIM employs a deep residual neural network to enhance the quality of SIM imaging, particularly in scenarios involving low-contrast illumination stripes. The key contribution of this study is the achievement of reliable SR image reconstruction even in suboptimal illumination contrast conditions. The results of our study will benefit various scientific disciplines.
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High throughput has become an important research direction in the field of super-resolution (SR) microscopy, especially in improving the capability of dynamic observations. In this study, we present a hexagonal lattice structured illumination microscopy (hexSIM) system characterized by a large field of view (FOV), rapid imaging speed, and high power efficiency. Our approach employs spatial light interference to generate a two-dimensional hexagonal SIM pattern, and utilizes electro-optical modulators for high-speed phase shifting. This design enables the achievement of a 210-µm diameter SIM illumination FOV when using a 100×/1.49 objective lens, capturing 2048 × 2048 pixel images at an impressive 98 frames per second (fps) single frame rate. Notably, this method attains a near 100% full field-of-view and power efficiency, with the speed limited only by the camera's capabilities. Our hexSIM demonstrates a substantial 1.73-fold improvement in spatial resolution and necessitates only seven phase-shift images, thus enhancing the imaging speed compared to conventional 2D-SIM.
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g-C3N4/Ag-ZnO (CAZ) composite photocatalysts were synthesized successfully by the hydrothermal method. The photocatalytic performance of photocatalysts was assessed through experiments measuring both hydrogen (H2) production and the degradation of methylene blue (MB). The H2 production rate of 60% CAZ reached 2.450 mmol·g-1·h-1, which was 8.5 times that of g-C3N4. 25% CAZ degraded 99.14% of MB dye within 40 min, and its degradation rate constant was 12.4 times that of g-C3N4. CAZ composite photocatalysts have good synergistic properties in degradation and hydrogen production and exhibit better photocatalytic performance. A Z-scheme photocatalytic system mechanism of CAZ has been proposed for the enhanced H2 production and photocatalytic degradation rate.
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The exceptional hydrophobicity and antifouling properties of polydimethylsiloxane (PDMS) composites have attracted extensive interest as a result of low surface energy. However, PDMS composites are hardly bound by common primers, greatly limiting their practical applications. To address this issue, an EPMS/VTMS (EV) primer synthesized by hydrolytic polycondensation of 3-[(2,3)-epoxypropoxypropyl]methyldiethoxysilane (EPMS) and vinyltrimethoxysilane (VTMS) in acidic conditions is proposed. Interestingly, the EV primer exhibits exceptional reactivity, self-healing capabilities, and strong adhesion to various substrates, including metals, plastics, and glass. The bonding aluminum plates are easily debonded by immersion in water without any residue left. Subsequently, the EV primer has been applied to the interface between silicone leather and the PDMS composite. Results show that the bonding strength for the silicone leather coated with the EV/PDMS composite is 16 times higher than that of the silicone leather modified with the PDMS composite. Meanwhile, the modified silicone leather exhibits impressive antifouling performance, including aqueous and oily stains, appreciable breathability, and excellent wear resistance, even if suffering from 20â¯000 cycles of abrasion. These excellent advantages for the modified silicone leather should be attributable to the synergistic effect of the EV primer and the PDMS composite. These findings pave the way to develop an ecofriendly debonding primer for PDMS composites, greatly facilitating applications of silicone leather.
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The aim of this study was to observe the therapeutic effect of sintilimab combined with a modified docetaxelâ +â cisplatinâ +â fluorouracil (DCF) regimen on advanced gastric cancer and its effect on Th1/Th2 immune balance. Ninety-eight cases of advanced gastric cancer patients who visited our hospital from April 2020 to May 2022 were selected and divided into 48 cases each in the conventional group and the research group by random number table method; the DCF regimen was adopted in the conventional group, and sintilimab combined with modified DCF regimen was adopted in the research group, and the therapeutic effects of the patients in the two groups and the changes of Th1/Th2 immune indexes were compared. CEA, CA199, CA242, CD168 AQ3, and IL-4 in the study group were lower than those in the conventional group at the end of three cycles of treatment, and the difference was statistically significant ( P â <â 0.001). The levels of IFN-γ and IL-4 in the study group at the end of three cycles of treatment were higher than those in the conventional group ( P â <â 0.001). The incidence of adverse reactions during treatment in the study group was lower than that in the conventional group ( P â <â 0.001), and the grading of adverse reactions in the study group was milder than that in the conventional group. Sintilimab combined with a modified DCF regimen in the treatment of advanced gastric cancer not only improves the therapeutic effect but also positively affects the Th1/Th2 immune balance, which provides better immune regulation for patients with advanced gastric cancer.
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Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Cisplatino , Docetaxel , Fluoruracila , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Fluoruracila/administração & dosagem , Cisplatino/administração & dosagem , Docetaxel/administração & dosagem , Docetaxel/uso terapêutico , Interleucina-4 , Equilíbrio Th1-Th2/efeitos dos fármacos , Idoso , Células Th1/imunologia , Células Th1/efeitos dos fármacos , Interferon gama , Células Th2/imunologia , Células Th2/efeitos dos fármacos , AdultoRESUMO
Photocatalytic reduction of carbon dioxide is a technology that effectively utilizes CO2and solar energy. Sodium niobate (NaNbO3) has received much attention in the field of photocatalysis due to its excellent photocatalytic properties. However, the application of NaNbO3in the field of photocatalysis is still limited by poor reaction to visible light and easy recombination of photo-generated carriers. Heterojunction with g-C3N4to construct core-shell structure can effectively improve the above problems. Combining the two can design a core-shell composite material that is beneficial for photocatalytic reduction of CO2. Herein, we prepared a core-shell heterojunction g-C3N4/NaNbO3by uniformly impregnating urea on the surface of NaNbO3chromium nanofibers with NaNbO3nanofibers prepared by electrospinning as a catalyst carrier, and urea as a precursor of g-C3N4. The core-shell structure of g-C3N4/NaNbO3was verified by a series of characterization methods such as XPS, XRD, and TEM. It was found that under the same conditions, the methanol yield of core-shell g-C3N4/NaNbO3was 12.86µmol·g-1·h-1, which is twice that of pure NaNbO3(6.67µmol·g-1·h-1). This article highlights an impregnation method to build core-shell structures for improved photocatalytic reduction of CO2.
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BACKGROUND: Oxidative stress may contribute to cardiac ryanodine receptor (RyR2) dysfunction in diabetic cardiomyopathy. Ginsenoside Rb1 (Rb1) is a major pharmacologically active component of ginseng to treat cardiovascular diseases. Whether Rb1 treat diabetes injured heart remains unknown. This study was to investigate the effect of Rb1 on diabetes injured cardiac muscle tissue and to further investigate its possible molecular pharmacology mechanisms. METHODS: Male Sprague-Dawley rats were injected streptozotocin solution for 2 weeks, followed 6 weeks Rb1 or insulin treatment. The activity of SOD, CAT, Gpx, and the levels of MDA was measured; histological and ultrastructure analyses, RyR2 activity and phosphorylated RyR2(Ser2808) protein expression analyses; and Tunel assay were performed. RESULTS: There was decreased activity of SOD, CAT, Gpx and increased levels of MDA in the diabetic group from control. Rb1 treatment increased activity of SOD, CAT, Gpx and decreased the levels of MDA as compared with diabetic rats. Neutralizing the RyR2 activity significantly decreased in diabetes from control, and increased in Rb1 treatment group from diabetic group. The expression of phosphorylation of RyR2 Ser2808 was increased in diabetic rats from control, and were attenuated with insulin and Rb1 treatment. Diabetes increased the apoptosis rate, and Rb1 treatment decreased the apoptosis rate. Rb1 and insulin ameliorated myocardial injury in diabetic rats. CONCLUSIONS: These data indicate that Rb1 could be useful for mitigating oxidative damage, reduced phosphorylation of RyR2 Ser2808 and decreased the apoptosis rate of cardiomyocytes in diabetic cardiomyopathy.
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Antioxidantes , Apoptose , Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Ginsenosídeos , Miócitos Cardíacos , Estresse Oxidativo , Ratos Sprague-Dawley , Canal de Liberação de Cálcio do Receptor de Rianodina , Estreptozocina , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Masculino , Estresse Oxidativo/efeitos dos fármacos , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/efeitos dos fármacos , Ginsenosídeos/farmacologia , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/patologia , Cardiomiopatias Diabéticas/fisiopatologia , Cardiomiopatias Diabéticas/etiologia , Apoptose/efeitos dos fármacos , Antioxidantes/farmacologia , Fosforilação , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Miócitos Cardíacos/metabolismo , Miocárdio/patologia , Miocárdio/metabolismo , Insulina , Malondialdeído/metabolismoRESUMO
Late blight, caused by the notorious pathogen Phytophthora infestans, poses a significant threat to potato (Solanum tuberosum) crops worldwide, impacting their quality as well as yield. Here, we aimed to investigate the potential use of cinnamaldehyde, carvacrol, and eugenol as control agents against P. infestans and to elucidate their underlying mechanisms of action. To determine the pathogen-inhibiting concentrations of these three plant essential oils (PEOs), a comprehensive evaluation of their effects using gradient dilution, mycelial growth rate, and spore germination methods was carried out. Cinnamaldehyde, carvacrol, and eugenol were capable of significantly inhibiting P. infestans by hindering its mycelial radial growth, zoospore release, and sporangium germination; the median effective inhibitory concentration of the three PEOs was 23.87, 8.66, and 89.65 µl/liter, respectively. Scanning electron microscopy revealed that PEOs caused the irreversible deformation of P. infestans, resulting in hyphal shrinkage, distortion, and breakage. Moreover, propidium iodide staining and extracellular conductivity measurements demonstrated that all three PEOs significantly impaired the integrity and permeability of the pathogen's cell membrane in a time- and dose-dependent manner. In vivo experiments confirmed the dose-dependent efficacy of PEOs in reducing the lesion diameter of potato late blight. Altogether, these findings provide valuable insight into the antifungal mechanisms of PEOs vis-à-vis late blight-causing P. infestans. By utilizing the inherent capabilities of these natural compounds, we could effectively limit the harmful impacts of late blight on potato crops, thereby enhancing agricultural practices and ensuring the resilience of global potato food production.
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Cimenos , Eugenol , Óleos Voláteis , Phytophthora infestans , Doenças das Plantas , Solanum tuberosum , Phytophthora infestans/efeitos dos fármacos , Phytophthora infestans/fisiologia , Solanum tuberosum/microbiologia , Óleos Voláteis/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Eugenol/farmacologia , Cimenos/farmacologia , Monoterpenos/farmacologia , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Óleos de Plantas/farmacologia , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Esporos/efeitos dos fármacos , Esporos/fisiologia , Acroleína/análogos & derivadosRESUMO
Advanced glycation end-products (AGEs) are complex compounds closely associated with several chronic diseases, especially diabetes mellitus (DM). Current methods for detecting AGEs are not suitable for screening large populations, or for long-term monitoring. This paper introduces a portable autofluorescence detection system that measures the concentration of AGEs in the skin based on the fluorescence characteristics of AGEs in biological tissues. The system employs a 395 nm laser LED to excite the fluorescence of AGEs, and uses a photodetector to capture the fluorescence intensity. A model correlating fluorescence intensity with AGEs concentration facilitates the detection of AGEs levels. To account for the variation in optical properties of different individuals' skin, the system includes a 520 nm light source for calibration. The system features a compact design, measuring only 60 mm × 50 mm × 20 mm, and is equipped with a miniature STM32 module for control and a battery for extended operation, making it easy for subjects to wear. To validate the system's effectiveness, it was tested on 14 volunteers to examine the correlation between AGEs and glycated hemoglobin, revealing a correlation coefficient of 0.49. Additionally, long-term monitoring of AGEs' fluorescence and blood sugar levels showed a correlation trend exceeding 0.95, indicating that AGEs reflect changes in blood sugar levels to some extent. Further, by constructing a multivariate predictive model, the study also found that AGEs levels are correlated with age, BMI, gender, and a physical activity index, providing new insights for predicting AGEs content and blood sugar levels. This research supports the early diagnosis and treatment of chronic diseases such as diabetes, and offers a potentially useful tool for future clinical applications.
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Produtos Finais de Glicação Avançada , Humanos , Produtos Finais de Glicação Avançada/análise , Feminino , Masculino , Adulto , Hemoglobinas Glicadas/análise , Pessoa de Meia-Idade , Glicemia/análise , Pele/química , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/sangue , Fluorescência , Imagem Óptica/métodos , Imagem Óptica/instrumentação , Espectrometria de Fluorescência/métodosRESUMO
The catalyst-reconstruction makes it challenging to clarify the practical active sites and unveil the actual reaction mechanism during the CO2 electroreduction reaction (CO2 RR). However, currently the impact of the electrolyte microenvironment in which the electrolyte is in contact with the catalyst is overlooked and might induce a chemical evolution, thus confusing the reconstruction process and mechanism. In this work, the carbonate adsorption properties of metal oxides were investigated, and the mechanism of how the electrolyte carbonate affect the chemical evolution of catalysts were discussed. Notably, Bi2 O3 with weak carbonate adsorption underwent a chemical reconstruction to form the Bi2 O2 CO3 /Bi2 O3 heterostructure. Furthermore, in situ and ex situ characterizations unveiled the formation mechanism of the heterostructure. The in situ formed Bi2 O2 CO3 /Bi2 O3 heterostructure with strong electron interaction served as the highly active structure for CO2 RR, achieving a formate Faradaic efficiency of 98.1 % at -0.8 Vvs RHE . Theoretical calculations demonstrate that the significantly tuned p-orbit electrons of the Bi sites in Bi2 O2 CO3 /Bi2 O3 optimized the adsorption of the intermediate and lowered the energy barrier for the formation of *OCHO. This work elucidates the mechanism of electrolyte microenvironment for affecting catalyst reconstruction, which contributes to the understanding of reconstruction process and clarification of the actual catalytic structure.
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BACKGROUND: Cerebral stroke is a leading cause of death and disability worldwide. Ligusticum Chuanxiong Hort. (LCH), a well-known Chinese herb, is widely used for the treatment of cerebral stroke. This study aimed to investigate the underlying mechanisms of LCH in cerebral stroke and develop a diagnostic model. METHODS: We employed network pharmacology analyses to identify the active compounds, targets, and underlying mechanisms of LCH for treating cerebral stroke. Molecular docking was performed to visualize the binding site between the core active compounds and hub targets. Furthermore, a diagnostic model for cerebral stroke was constructed based on transcriptomic analysis. RESULTS: Our findings revealed that LCH contains multiple active ingredients, including oleic acid and caffeic acid. Protein-protein interaction network analysis identified IL1B, CCL2, MAPK3, PTGS2, JUN, MMP9, TLR4, HIF1A, PPARA, FOS, PTEN, NFE2L2, TLR2, TIMP1, and SOD2 as the top 15 hub genes. Kyoto Encyclopedia of Genes and Genomes pathway analysis highlighted the enrichment of TNF and IL-17 signaling pathways. Molecular docking analysis demonstrated binding sites between oleic acid, caffeic acid, and MMP9, PPARP, PTEN, and TIMP1. The diagnostic model indicated that FOS, MMP9, PPARA, PTEN, TIMP1, and TLR2 serve as blood biomarkers for cerebral stroke. CONCLUSIONS: This study demonstrates that LCH alleviates the symptoms following cerebral stroke through interactions with the TNF and IL-17 signaling pathways. The findings contribute to a better understanding of the therapeutic mechanisms of LCH and offer insights into the development of a diagnostic model for cerebral stroke.
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Interleucina-17 , Ligusticum , Metaloproteinase 9 da Matriz , Simulação de Acoplamento Molecular , Farmacologia em Rede , Ácido Oleico , Receptor 2 Toll-Like , Perfilação da Expressão GênicaRESUMO
The widespread occurrence of aerated plain soils underscores their significant role in the global soil methane (CH4) sink budget. However, plain soils are poorly characterized in terms of spatial variability of CH4 uptake and the relevant control. We investigated the intra- and inter-site spatial variability of CH4 uptake through flux measurements in intact soil cores from five non-wetland sites within the Yellow River Delta, each representing a distinct land use/cover type. Methane uptake rates were highest in undisturbed forest cores. The rates were very low, often falling below the detection limit, in cores from the other four sites. The significant correlation between CH4 uptake and bulk density across sites suggests the integrative role of bulk density for the effects of different disturbances (including salt stress and succession) on CH4 uptake. Methane uptake was heterogeneous at the within-site scale as indicated by large coefficients of variations (CVs). Soil texture variation manipulated the within-site pattern of CH4 uptake in the low-salinity sites. Salt affected the spatial variation of CH4 uptake only at high level of salinity. Neither Potter's nor Ridgwell's models effectively captured the within-site variation of CH4 uptake due to a texture-associated bias in the models. Establishing a quantitative relationship between CH4 uptake and clay content at the field scale in alluvial plain soils will facilitate the refinement of model parameters linked to texture and rectify biases in CH4 estimation. These results provide an insight for the biogeochemical control of CH4 uptake in alluvial plain soils and have important application for improving CH4 models.
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Due to the high-dimensionality, redundancy, and non-linearity of the near-infrared (NIR) spectra data, as well as the influence of attributes such as producing area and grade of the sample, which can all affect the similarity measure between samples. This paper proposed a t-distributed stochastic neighbor embedding algorithm based on Sinkhorn distance (St-SNE) combined with multi-attribute data information. Firstly, the Sinkhorn distance was introduced which can solve problems such as KL divergence asymmetry and sparse data distribution in high-dimensional space, thereby constructing probability distributions that make low-dimensional space similar to high-dimensional space. In addition, to address the impact of multi-attribute features of samples on similarity measure, a multi-attribute distance matrix was constructed using information entropy, and then combined with the numerical matrix of spectral data to obtain a mixed data matrix. In order to validate the effectiveness of the St-SNE algorithm, dimensionality reduction projection was performed on NIR spectral data and compared with PCA, LPP, and t-SNE algorithms. The results demonstrated that the St-SNE algorithm effectively distinguishes samples with different attribute information, and produced more distinct projection boundaries of sample category in low-dimensional space. Then we tested the classification performance of St-SNE for different attributes by using the tobacco and mango datasets, and compared it with LPP, t-SNE, UMAP, and Fisher t-SNE algorithms. The results showed that St-SNE algorithm had the highest classification accuracy for different attributes. Finally, we compared the results of searching the most similar sample with the target tobacco for cigarette formulas, and experiments showed that the St-SNE had the highest consistency with the recommendation of the experts than that of the other algorithms. It can provide strong support for the maintenance and design of the product formula.
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Frequency-dependent predation is common in predator-prey interactions. Size is an important characteristic of seeds and is crucial in the regeneration stage of plant seeds. However, the frequency dependence of animal predation on seed size has not been reported. In this study, we conducted a field experiment and used different sizes of Liaodong oak (Quercus wutaishanica) seeds to test the frequency dependence of intraspecific seed size selection in rodents. We used the number ratio of large to small seeds as the frequency. The results show that the rate of small seeds being eaten in situ was significantly higher than that of large seeds (p < 0.05). The rates of different-sized seeds being eaten after removal decreased with increasing frequencies, and there was no significant difference between frequencies except for 1:9 and 9:1. The rates of large seeds being scatter-hoarded were significantly higher than those of small seeds at different frequencies (p < 0.05). The eating distances after removal of large seeds were significantly longer than those of small seeds at the same frequencies (p < 0.05). Furthermore, the scatter-hoarding distances of large seeds were significantly longer than those of small seeds at three frequencies (1:9, 3:7, and 9:1) (p < 0.05). That is, rodents consumed more small seeds in situ, dispersed and scatter-hoarded more large seeds, and dispersed large seeds over longer distances. Rodents exhibited a negative frequency dependence for small seeds and a positive frequency dependence for large seeds on being eaten in situ. Moreover, rodents exhibited a negative frequency dependence for large seeds and a positive frequency dependence for small seeds on being eaten after removal and scatter-hoarding. These results reveal the frequency dependence of rodent selection on seed size and provide new insights into animal-mediated seed dispersal and the regeneration of plant populations.
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The properties of microplastics determine their settling velocities and affect the fates and migration pathways of microplastics. This paper has simulated the settling velocities of film-shaped microplastics, which are present in natural aquatic environments. The numerical results provided more data to fit the terminal settling velocities of film-shaped microplastics. Comparison between the particle definition and the equivalent spherical diameter confirmed that the particle definition is more suitable for film-shaped microplastics. In the transitional flow regime, CD decreases linearly with Re. As Re further increases, CD gradually converges at approximately 1.20. By integrating the experimental and simulated data, a new explicit formula for predicting the settling velocity of film-shaped microplastics has been presented with the optimal shape parameter f. The presented formula achieves better performance (MAPE = 6.6 %, RMSE = 16.8 %, and R2 = 0.99) than the existing formulas for settling velocity for film-shaped microplastics, closely rivaling that of the ensemble learning algorithm.
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Microplásticos , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodosRESUMO
This paper investigates the asymptotic tracking problem for a class of second-order electromagnetic micromirror model with output performance constraints and anomaly control, which is subject to model parameter uncertainties and external disturbances. Specifically, this paper formulates the trajectory tracking control problem of an electromagnetic micromirror as a closed-loop control trajectory tracking problem based on the general solution framework of output regulation. Moreover, the extended internal model is introduced to reformulate the closed-loop control problem into a state stabilization problem of the augmented system. Based on the augmented system, an internal model backstepping controller is proposed by integrating the barrier Lyapunov Functions (BLF) and the Nussbaum gain function with the backstepping structure.This controller not only satisfies the output performance constraints of the micromirror, but also maintains the control performance in anomalous control situations. The final performance simulation demonstrates the efficacy of the proposed controller.
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Tyrosinase (Polyphenol oxidase), a key enzyme in enzymatic browning, is an attractive target for developing new anti-browning agents in the food industry. In this work, twenty pyrazole-1,2,4-triazole derivatives (3a-3n, 4a-4f) were synthesized and tested in vitro, most of compounds showed potent anti-tyrosinase activity. Of these, 3c (IC50 = 1.02 ± 0.08 µM) was found to be 14 folds stronger than kojic acid (IC50 = 14.74 ± 1.23 µM) and behaved as a mixed type inhibitor. Besides, the disappeared peak of dopaquinone in the HPLC assay intuitively validated the inhibitory effect of 3c. Copper ions chelating, fluorescence quenching and molecular docking assays showed that coordination with copper is the key to play a role. Furthermore, 3c exhibited excellent anti-browning ability for the Rosa roxburghii Tratt, the non-enzymatic browning experiment showed that 3c could prevent browning in non-enzymatic ways. It is suggested that these derivatives could serve as the leading compounds to find more efficient anti-browning agents in the future.