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1.
Nature ; 608(7921): 62-68, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35922499

RESUMEN

Additive manufacturing produces net-shaped components layer by layer for engineering applications1-7. The additive manufacture of metal alloys by laser powder bed fusion (L-PBF) involves large temperature gradients and rapid cooling2,6, which enables microstructural refinement at the nanoscale to achieve high strength. However, high-strength nanostructured alloys produced by laser additive manufacturing often have limited ductility3. Here we use L-PBF to print dual-phase nanolamellar high-entropy alloys (HEAs) of AlCoCrFeNi2.1 that exhibit a combination of a high yield strength of about 1.3 gigapascals and a large uniform elongation of about 14 per cent, which surpasses those of other state-of-the-art additively manufactured metal alloys. The high yield strength stems from the strong strengthening effects of the dual-phase structures that consist of alternating face-centred cubic and body-centred cubic nanolamellae; the body-centred cubic nanolamellae exhibit higher strengths and higher hardening rates than the face-centred cubic nanolamellae. The large tensile ductility arises owing to the high work-hardening capability of the as-printed hierarchical microstructures in the form of dual-phase nanolamellae embedded in microscale eutectic colonies, which have nearly random orientations to promote isotropic mechanical properties. The mechanistic insights into the deformation behaviour of additively manufactured HEAs have broad implications for the development of hierarchical, dual- and multi-phase, nanostructured alloys with exceptional mechanical properties.

2.
Langmuir ; 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39321088

RESUMEN

The dynamic behavior of impacting droplet shearing by the surface edge with different wettabilities is complicated and has great significance for engineering application. The morphological evolution of droplet with various Weber numbers (We) and wettability impacting on the edge of square substrate is investigated by high-speed photography. Moreover, the effects of the contact angle (α) and Weber numbers (We) on the shear breaking process of droplets are obtained. There are three types morphological evolution of impacting droplet are observed experimentally, including unbroken, tensile breakup, and shear breakup. Contact angle and Weber number have been proved to be the significant factors affecting the type of droplet morphological evolution. Meanwhile, the critical Weber number of different types are obtained quantitatively. Moreover, as α increases, the critical Weber numbers for breakup increase. In the shear breakup process, the mass ratio between the droplets remaining on the substrate and the initial droplets is maintained at 50%. Particularly, a reliable prediction model for the spreading of droplet impacting the side wall is proposed and compared with the experimental data. Overall, this study provides new direction and guidance for exploring droplet breakup kinetics.

3.
J Environ Manage ; 353: 120172, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38310799

RESUMEN

Understanding pesticide residue patterns in crops is important for ensuring human health. However, data on residue accumulation and distribution in cowpeas grown in the greenhouse and open field are lacking. Our results suggest that acetamiprid, chlorantraniliprole, cyromazine, and thiamethoxam residues in greenhouse cowpeas were 1.03-15.32 times higher than those in open field cowpeas. Moreover, repeated spraying contributed to the accumulation of pesticide residues in cowpeas. Clothianidin, a thiamethoxam metabolite, was detected at 1.04-86.00 µg/kg in cowpeas. Pesticide residues in old cowpeas were higher than those in tender cowpeas, and the lower half of the plants had higher pesticide residues than did the upper half. Moreover, pesticide residues differed between the upper and lower halves of the same cowpea pod. Chronic and acute dietary risk assessments indicated that the human health risk was within acceptable levels of cowpea consumption. Given their high residue levels and potential accumulation, pesticides in cowpeas should be continuously assessed.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Vigna , Humanos , Tiametoxam/análisis , Tiametoxam/metabolismo , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/química , Vigna/metabolismo , Bioacumulación , Contaminación de Alimentos/análisis
4.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1579-1586, 2024 Mar.
Artículo en Zh | MEDLINE | ID: mdl-38621942

RESUMEN

This study aims to investigate the effects of Gualou Xiebai Banxia Decoction(GXBD) on type 2 diabetes mellitus(T2DM) combined with acute myocardial infarction(AMI) in rats via chemerin/chemokine-like receptor 1(CMKLR1)/peroxisome proliferator-activated receptor α(PPARα) signaling pathway, and to explore the mechanism of GXBD in alleviating glucose and lipid metabolism disorders. The SD rats were randomized into control, model, positive control, and low-and high-dose GXBD groups. The rat model of T2DM was established by administration with high-fat emulsion(HFE) by gavage and intraperitoneal injection with streptozotocin, and then coronary artery ligation was performed to induce AMI. The control and model groups were administrated with the equal volume of normal saline, and other groups were administrated with corresponding drugs by gavage. Changes in relevant metabolic indicators were assessed by ELISA and biochemical assays, and the protein levels of chemerin, CMKLR1, and PPARα in the liver, abdominal fat, and heart were determined by Western blot. The results showed that GXBD alleviated the myocardial damage and reduced the levels of blood lipids, myocardial enzymes, and inflammatory cytokines, while it did not lead to significant changes in blood glucose. Compared with the model group, GXBD down-regulated the expression of chemerin in peripheral blood and up-regulated the expression of cyclic adenosine monophosphate(cAMP) and protein kinase A(PKA) in the liver. After treatment with GXBD, the protein levels of chemerin and CMKLR1 in the liver, abdominal fat, and heart were down-regulated, while the protein levels of PPARα in the liver and abdominal fat were up-regulated. In conclusion, GXBD significantly ameliorated the disorders of glycolipid metabolism in the T2DM-AMI model by regulating the chemerin/CMKLR1/PPARα signaling pathway to exert a protective effect on the damaged myocardium. This study provides a theoretical basis for further clinical study of GXBD against T2DM-AMI and is a manifestation of TCM treatment of phlegm and turbidity causing obstruction at the protein level.


Asunto(s)
Diabetes Mellitus Tipo 2 , Medicamentos Herbarios Chinos , Infarto del Miocardio , Ratas , Animales , PPAR alfa/genética , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Ratas Sprague-Dawley , Transducción de Señal , Infarto del Miocardio/tratamiento farmacológico , Quimiocinas
5.
Rapid Commun Mass Spectrom ; 37(1): e9403, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36184262

RESUMEN

RATIONALE: Fritillaria cirrhosae bulbus (BFC), a typical traditional Chinese medicine with multiple botanical sources, has been used for relieving cough and reducing sputum. Studies have shown that there were obvious differences in the chemical compositions and clinical efficacy of different sources of BFC. How to characterise BFC from botanical sources accurately and quickly is vital for drug quality evaluation and clinical applications. METHODS: In the present study, an integrated strategy of plant metabolomics combined with the target network pharmacology was developed to characterise BFC. Plant metabolomics analysis was performed to screen out the chemical markers of six species of BFC. Then, target network pharmacology was applied to explore the relationship between chemical markers and related diseases. Finally, potential Q-markers for species characterization were selected by combined analysis of plant metabolomics and the target network pharmacology. RESULTS: A total of 67 Fritillaria alkaloid compounds were identified. Six species showed clear characterization by multivariate statistical analysis, resulting in 12 chemical markers. Meanwhile, a total of nine components related to asthma were screened out based on the target network pharmacology. Taking content difference and pharmacological activity into consideration, nine constituents were selected as potential Q-markers. CONCLUSION: The method developed provided not only a standard protocol for characterising different species of BFC directly, but also an effective approach for multisource medicines discrimination.


Asunto(s)
Medicamentos Herbarios Chinos , Fritillaria , Medicamentos Herbarios Chinos/química , Farmacología en Red , Fritillaria/química , Medicina Tradicional China , Metabolómica
6.
Fish Shellfish Immunol ; 141: 109040, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37648118

RESUMEN

Galectins, a family of lectins that bind to ß-galactoside, possess conserved carbohydrate recognition domains (CRDs) and play a crucial role in recognizing and eliminating pathogens in invertebrates. Two galectin-4 genes (PcGal4) isoforms, named PcGal4-L and PcGal4-L-CRD, were cloned from the cDNA library of Procambarus clarkia in our study. PcGal4-L contains an open reading frame (ORF, 1089 bp), which encodes a protein consisting of 362 amino acids including a single CRD and six low complexity regions. The full-length cDNA of PcGal4-L-CRD contains a 483 bp ORF that encodes a protein of 160 amino acids, with a single CRD and a low-complexity region. The difference between the two PcGal4 isoforms is that PcGal4-L has 202 additional amino acids after the CRD compared to the PcGal4-L-CRD. These two isoforms are grouped together with other galectins from crustaceans through phylogenetic analysis. Further study revealed that total PcGal4 (including PcGal4-L and PcGal4-L-CRD) was primarily expressed in the muscle, gills and intestine. The mRNA levels of total PcGal4 in gills and hemocytes were significantly induced after challenge with Aeromonas hydrophila. Both recombinant PcGal4-L and its spliced isoform, PcGal4-L-CRD, could directly bind to lipopolysaccharides, peptidoglycan and five tested microorganisms, inducing a wide spectrum of microbial agglutination. The spliced isoform PcGal4-L-CRD showed a stronger binding ability than PcGal4-L. In addition, when the PcGal4 was knockdown, transcriptions of seven antimicrobial peptides (AMPs) genes (ALF5, ALF6, ALF8, CRU1, CRU2, CRU3 and CRU4) in gills and seven AMPs genes (ALF5, ALF6, ALF8, ALF9, CRU1, CRU3 and CRU4) in hemocytes were significantly decreased. Meanwhile, the survival rate of P. clarkii decreased in the PcGal4-dsRNA group. In summary, these results indicate that PcGal4 can mediate the innate immunity in P. clarkii by bacterial recognition and agglutination, as well as regulating AMP expression, thus recognition and understanding of the functions of galectin in crustaceans in immune resistance.

7.
Anal Biochem ; 629: 114297, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34217704

RESUMEN

Genuine regional drugs have played a vital role in clinical use for a long time. There are differences in traditional Chinese medicines (TCM) from different regions based on their chemical composition. Differences in chemical composition may lead to deviations in therapeutic effects. To our knowledge, to date, there are no effective methods for distinguishing genuine regional drugs based on the differences in their chemical composition. Therefore, establishing an analytical platform for distinguishing the compounds used in TCM from various geographical locations is essential. In this work, an integrated platform based on UPLC-Q-TOF-MS/MS combined with plant metabolomics approach was established for comprehensively distinguishing genuine regional drugs. Isodon rubescens (Hemsl.) Hara, a widely used herbal medicine of China, was chosen for this study and 24 samples from four geographical locations in China were collected. A total of 60 ent-kaurane diterpenoids were tentatively identified, and then the samples from four geographical origins were distinguished using PCA (principal component analysis) and PLS-DA (partial least squares discrimination analysis). Different compounds were identified among the samples collected from the four geographical locations, and 12 of them were regarded as marker compounds responsible for the distinction. Our study highlights the essence and predictive ability of metabolomics in detecting minute differences in the same varieties of TCM samples based on the levels and compositions of their metabolites. These results showed that the analysis using UHPLC-Q-TOF-MS/MS combined with metabolomics could be applied to distinguish the geographical origins and varieties of TCM.


Asunto(s)
Biomarcadores/análisis , Diterpenos/análisis , Medicamentos Herbarios Chinos/análisis , Isodon/química , Cromatografía Líquida de Alta Presión , Análisis de los Mínimos Cuadrados , Medicina Tradicional China , Metabolómica , Análisis Multivariante , Análisis de Componente Principal , Espectrometría de Masas en Tándem
8.
Sensors (Basel) ; 20(18)2020 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-32957432

RESUMEN

This paper presents a capacitive displacement sensor based on a capacitively fed inverted-F antenna (CFIFA) for displacement detection. The sensor is composed of a grounded L-shape patch and a rectangular upper patch, forming a capacitor between them. The asymmetric dipole model is adopted to explain the frequency shift and current distribution of the proposed antenna sensor at its first-order resonance. The numerical simulation of the CFIFA using the Ansoft high-frequency structure simulator (HFSS) software is carried out to optimize the dimensional parameters, allowing the antenna to perform better. Two sets of CFIFAs are fabricated and tested for verification. Results show that the CFIFA has a good linear relationship between its first resonant frequency and the relative displacement, and is capable of a long range of displacement measuring.

9.
Sensors (Basel) ; 20(17)2020 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-32872290

RESUMEN

This paper presents a passive wireless long-range displacement sensor that is based on the circular patch antenna, and the detecting range of the sensor can be customized. The sensor consists of a chipped circular antenna with two opened rectangular windows, a substrate, and a ground plate with a sloping channel. No bonding between the antenna and the ground plate allows for the chipped antenna to slide along the sloping channel. The channel will drive the current flow on the plate once the chip is activated, increasing the effective electrical length and, consequently, decreasing the resonant frequency of the circular antenna. The sensing mechanism equates the measuring displacement to the relative movement of the antenna with respect to the ground that achieves the measurement of long-range displacement and, thus, the proposed sensor can avoid stress damage to the antenna due to excessive deformation. Three different range sensors were simulated in the the Ansoft high frequency structure simulator (HFSS). The results show that the resonance frequency of the antenna has a linear relationship with the varying chute depth beneath the chip. Three sensors were fabricated, and the experimental results also validated that the sensitivity of the sensor can be adjusted.

10.
Molecules ; 25(3)2020 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-31979297

RESUMEN

The experiment developed the ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC/MS/MS) method for testing emamectin benzoate, and studied the metabolism of emamectin benzoate in rice plants and rice-growing environments via application of this testing method. The dissipation curve of emamectin benzoate standard substance was good at 0.5-200 µg L-1, and its correlation coefficient was greater than 0.99. In the concentration range of 0.1-50 µg kg-1, the average recovery rate of plants, soil, and field water was 82 %-102 %, and relative standard deviation (RSD) was between 0.3 % and 15.9 %. Half-lives in rice plants and soil were 0.8-2.8 days and 1.9-3.8 days, respectively, and emamectin benzoate was not detected in rice or rice hull. The experiment showed that emamectin benzoate is harmless to human health at the concentration recommended by the manufacturer.


Asunto(s)
Cromatografía Liquida/métodos , Ivermectina/análogos & derivados , Oryza/química , Residuos de Plaguicidas/análisis , Suelo/química , Espectrometría de Masas en Tándem/métodos , Monitoreo del Ambiente/métodos , Ivermectina/química , Ivermectina/metabolismo , Tallos de la Planta/química , Sensibilidad y Especificidad
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