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The emergence and spread of antibiotic resistance in the environment pose a serious threat to global public health. It is acknowledged that non-antibiotic stresses, including disinfectants, pharmaceuticals and organic pollutants, play a crucial role in horizontal transmission of antibiotic resistance genes (ARGs). Despite the widespread presence of non-steroidal anti-inflammatory drugs (NSAIDs), notably in surface water, their contributions to the transfer of ARGs have not been systematically explored. Furthermore, previous studies have primarily concentrated on model strains to investigate whether contaminants promote the conjugative transfer of ARGs, leaving the mechanisms of ARG transmission among antibiotic resistant bacteria in natural aqueous environments under the selective pressures of non-antibiotic contaminants remains unclear. In this study, the Escherichia coli (E. coli) K12 carrying RP4 plasmid was used as the donor strain, indigenous strain Aeromonas veronii containing rifampicin resistance genes in Taihu Lake, and E. coli HB101 were used as receptor strains to establish inter-genus and intra-genus conjugative transfer systems, examining the conjugative transfer frequency under the stress of ketoprofen. The results indicated that ketoprofen accelerated the environmental spread of ARGs through several mechanisms. Ketoprofen promoted cell-to-cell contact by increasing cell surface hydrophobicity and reducing cell surface charge, thereby mitigating cell-to-cell repulsion. Furthermore, ketoprofen induced increased levels of reactive oxygen species (ROS) production, activated the DNA damage-induced response (SOS), and enhanced cell membrane permeability, facilitating ARG transmission in intra-genus and inter-genus systems. The upregulation of outer membrane proteins, oxidative stress, SOS response, mating pair formation (Mpf) system, and DNA transfer and replication (Dtr) system related genes, as well as the inhibition of global regulatory genes, all contributed to higher transfer efficiency under ketoprofen treatment. These findings served as an early warning for a comprehensive assessment of the roles of NSAIDs in the spread of antibiotic resistance in natural aqueous environments.
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By using PacBio HiFi technology, we produced over 700 Gb of long-read sequencing (LRS) raw data; and by using Illumina paired-end whole-genome shotgun (WGS) sequencing technology, we generated more than 70 Gb of short-read sequencing (SRS) data. With LRS data, we assembled one genome and then generate a set of annotation data for an early-matured Geng/japonica glutinous rice mega variety genome, Longgeng 57 (LG57), which carries multiple elite traits including good grain quality and wide adaptability. Together with the SRS data from three parents of LG57, pedigree genome variations were called for three representative types of genes. These data sets can be used for deep variation mining, aid in the discovery of new insights into genome structure, function, and evolution, and help to provide essential support to biological research in general.
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Genoma de Planta , Oryza , Oryza/genética , Fenótipo , Análise de Sequência de DNA , Sequenciamento Completo do GenomaRESUMO
Introduction: In order to solve the problems of inaccurate fertilization, unstable fertilization and low fertiliserutilization rate in mango orchard. Methods: A small spiral fertiliser discharger was designed based on the agronomic characteristics of fertilization in mango orchard. The fertilizing performance test and parameter optimization of thespiral fertiliser discharger were carried out by combining bench and simulation test. Firstly, the main influencing factors of the fertilizing performance of the spiral fertiliser discharger were analyzed by theoretical calculation formula, and the range of its value was preliminarily determined. At the same time, the digital and discrete element models of the spiral fertiliser discharger were established. Then,the discrete element model of granular fertiliser was established on the basis of the physical and related mechanical simulation parameters of granular fertiliser obtained by experimental statistics.Taking the variable coefficient of fertilizing stability as the response value, the method of singlefactor simulation fertilizing test was used to explore the parameters that have a significant influence on the variable coefficient of fertilizing stability. The response surface method (RSM) was used tosimulate the fertilizing performance of three significant parameters. Based on the quadraticregression orthogonal rotation combination design test, a second-order regression mathematicalmodel between the variable coefficient of fertilizing stability and the significant parameters wasestablished. The variable coefficient of fertilizing stability was as small as possible. The geneticalgorithm (GA) was used to optimize the regression model. Finally, the verification test of thefluidity and applicability of different fertilisers was carried out. Results: The results of single factor test showed that the diameter of spiral blade, pitch and rotationalspeed of fertilizing shaft have significant influence on the variable coefficient of fertilizing stability.The optimal parameter combination of the spiral fertiliser discharger was obtained: 98.44 mm for thediameter of spiral blade, 54.8 mm for the pitch, and 24.43 r/min for the rotational speed of fertilizingshaft. The verification results showed that the average relative error of the test was small, and themass flow rate of different fertilisers and the variable coefficient of fertilizing stability could meetthe agronomic requirements of fertilization in mango orchards. The reliability of the discrete elementsimulation test results and research methods of the spiral fertiliser discharger was verified. Conclusion: The results and methods of this study can provide reference for the development of mangoorchard fertilization machinery and related fertilizing performance test.
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The morphological changes of leaves under the airflow have a significant effect on the deposition of pesticide droplets on the leaves, but the wind-induced vibration of the leaves is complicated to measure. In this study, an aerodynamic test of the pear leaf was conducted in the wind tunnel, and binocular high-speed photography was used to record the deformation and vibration of the leaves under various airflow velocities. Experiments showed that air velocity (v) had a significant effect on the morphological response of the leaf. As v increased, the leaf was in three states, including static deformation, low-frequency vibration, and reconfiguration of airfoil steady state. The mutation from one state to another occurred at the critical velocity of vcr1 and vcr2 . By tracking the leaf marker point, various morphological parameters were calculated, including the bending angle of the petiole, the wind deflection angle, and the twist angle of leaves under different air velocities. When vcr1 ≤v ≤vcr2 , the parameters changed periodically. When v< vcr1 , the petiole and the leaf bent statically, and the bending angle of the petiole and the wind deflection angle of the leaf gradually increased. When v >vcr2 , the morphology of the leaf and the petiole was stable. Besides, this study tracked and measured the wind deflection area of leaf, which was consistent with the theoretical calculation results. The measurement of the leaf morphological parameters can reflect the morphological changes of leaves under airflow, thus providing a basis for the decision-making of air-assisted spray airflow.
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Particleboards are widely used in the artificial board market, which can be constructed from a variety of raw materials and require small amounts of energy to be produced. In the particleboard production process, forming machines play an important role as the key equipment for achieving continuous production. In recent years, airflow forming machines have received increasing attention in particleboard production lines because of their strong separation ability and low price. However, the internal flow field is complex and difficult to control, which affects the surface quality and strength of the particleboard. The most pressing technical difficulty is controlling the flow field characteristics of the airflow paver. At present, the research on this subject is conducted primarily through repeated experiments, which entail long research periods and high processing costs. To reduce human and financial costs, in this study, Computational Fluid Dynamics (CFD) is employed to investigate the flow field and the gas-solid two-phase flow field coupled with particle movement of an airflow forming machine. The accuracy of the calculation model is verified by comparing characteristic point velocities obtained from experimental analysis and a simulation. The simulation results show that in practical production, the frequency of a negative pressure fan should be greater than 27 Hz. It is necessary to set the shoulder properly, and the slab smoothness can be improved by moving the shoulder back on the premise of meeting the strength requirements of the box. The distance between the shoulders of the box body should be less than 2570 mm, and particles with uniform diameter should be added to the paving box to reduce the turbulence effect, improve the quality of particle forming and provide actual particleboard production with a solid theoretical foundation.
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Simulação por Computador , Madeira , Humanos , Hidrodinâmica , Teste de MateriaisRESUMO
Hyperspectral imaging (HSI) technique was investigated to explore a feasible protocol for detecting the potential offal (lung) adulteration in ground pork. Tested samples (176 adulterated and 2 controls) were first prepared with adulterant of ground lung in range of 0%-100% (w/w) at 10% intervals. After hyperspectral images were acquired and calibrated in reflectance mode (400-1000 nm), full spectra were extracted from identified regions of interests (ROIs) and then transformed into absorbance and Kubelka-Munck spectral units, respectively. Partial least squares regression (PLSR) models based on full spectra showed that raw reflectance spectra with no preprocessings performed best with coefficient of determination (Rp2) of 0.98, root mean square error (RMSEP) of 4.25%, and ratio performance deviation (RPD) of 7.53 in prediction set. To reduce the high dimensionality of spectra, data was further explored using principal component loadings, two-dimensional correlation spectroscopy (2D-COS), and regression coefficients (RC), respectively. The optimal performance of established simplified PLSR model were acquired using eleven featured wavelengths selected by PC loadings with Rp2 of 0.98, RMSEP of 4.47% and RPD of 7.16. Finally, the limit of detection (LOD) was calculated to be a satisfactory 7.58%, and readily discernible visualization procedure using preferred simplified PLSR model yielded satisfactory spatial distribution of adulteration situation. Control samples with known distribution were also visualized to successfully prove the validity. Consequently, this research offers an alternative assay for visually and rapidly detecting offal of lung adulteration in ground pork.
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Carne de Porco , Carne Vermelha , Animais , Imageamento Hiperespectral , Análise dos Mínimos Quadrados , Carne/análise , Carne Vermelha/análise , Espectroscopia de Luz Próxima ao Infravermelho , SuínosRESUMO
The most effective method for harvesting forest fruit is the mechanical vibration harvesting method. During the forced vibration process, the fruit will be shed from the tree when the inertia of the fruit is greater than the fruit's pedicel retention force. In order to study the movement response characteristics of the Ginkgo biloba fruit in depth, for a small Ginkgo biloba fruit tree, the frequency curve of the fruit tree had been obtained in this paper, based on the pulse hammer excitation method, and four resonant frequencies and four trough point frequencies, in the frequency range of 10 Hz~25 Hz, were determined as the test excitation frequency. Through a comparison test between the simulated fruit and the Ginkgo biloba fruit, both the simulated fruit and the real Ginkgo biloba fruit demonstrated good response consistency, and the results had shown that the simulated fruit could be used to replace the Ginkgo biloba fruit. The acceleration response of the resonant frequency and the trough point frequency for two test points of the two primary branches had also been analyzed. It was found that the resonant frequency caused an obvious harmonic response. For the same frequency, the fruit at some points produced a very strong vibrational response, while at other points the fruit was almost stationary. Therefore, it was difficult for a fruit tree to completely shed all its fruit through excitation at a single frequency. It was more difficult to induce a strong vibrational response of fruit on branches of higher stiffness. On the contrary, it was easier to induce a strong vibrational response on more flexible branches regardless of the resonant frequency or the trough point frequency excitation.
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Frutas , Ginkgo biloba , Vibração , Fenômenos Biomecânicos , Modelos TeóricosRESUMO
Chronic inflammatory disorder of the airways causes asthma. Regulatory T cells (Treg cells) and Natural killer T cells (NKT cells) both play critical roles in the pathogenesis of asthma. Activation of Treg cells requires Foxp3, whereas whether Foxp3 may regulate the ratio of Treg and NKT cells to affect asthma is uncertain. In an ovalbumin (OVA)-induced mouse model of asthma, we either increased Treg cells by lentivirus-mediated forced expression of exogenous Foxp3, or increased NKT cells by stimulation with its activator α-GalCer. We found that the CD4+CD25+ Treg cells increased by forced Foxp3 expression, and decreased by α-GalCer, while the CD3+CD161+ NKT cells decreased by forced Foxp3 expression, and increased by α-GalCer. Moreover, forced Foxp3 expression, but not α-GalCer, significantly alleviated the hallmarks of asthma. Furthermore, forced Foxp3 increased levels of IL_10 and TGFß1, and α-GalCer increased levels of IL_4 and INFγ in the OVA-treated lung. Taken together, our study suggests that Foxp3 may activate Treg cells and suppress NKT cells in asthma. Treg and NKT cells may antagonize the effects of each other in asthma.
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Asma/imunologia , Fatores de Transcrição Forkhead/metabolismo , Células T Matadoras Naturais/citologia , Células T Matadoras Naturais/imunologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia , Animais , Asma/complicações , Citocinas/metabolismo , Modelos Animais de Doenças , Galactosilceramidas/metabolismo , Células HEK293 , Humanos , Hipersensibilidade/complicações , Hipersensibilidade/imunologia , Lentivirus/metabolismo , Masculino , Camundongos Endogâmicos C57BL , OvalbuminaRESUMO
BACKGROUND: Adjuvants can improve pesticide application efficiency and effectiveness. However, quantifications of the adjuvant-amended pesticide droplet actions on foliage, which could affect application efficiencies, are largely unknown. RESULTS: Droplet evaporation rates and spread on waxy or hairy leaves varied greatly with the adjuvant types tested. On waxy leaves, the wetted areas of droplets containing crop oil concentrate (COC) were significantly smaller than those containing modified seed oil (MSO), non-ionic surfactant (NIS) or oil surfactant blend (OSB), whereas the evaporation rates of COC-amended droplets were significantly higher. On hairy leaves, COC-amended droplets remained on top of the hairs without wetting the epidermis. When the relative concentration was 1.50, the wetted area of droplets with NIS was 9.2 times lower than that with MSO and 6.1 times lower than that with OSB. The wetted area increased as the adjuvant concentration increased. MSO- or OSB-amended droplets spread extensively on the hairy leaf surface until they were completely dried. CONCLUSION: These results demonstrated that the proper concentration of MSO, NIS or OSB in spray mixtures improved the homogeneity of spray coverage on both waxy and hairy leaf surfaces and could reduce pesticide use. This article is a US Government work and is in the public domain in the USA.