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1.
Plant J ; 117(6): 1656-1675, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38055844

RESUMO

With global warming and climate change, abiotic stresses often simultaneously occur. Combined salt and heat stress was a common phenomenon that was severe, particularly in arid/semi-arid lands. We aimed to reveal the systematic responsive mechanisms of tomato genotypes with different salt/heat susceptibilities to combined salt and heat stress. Morphological and physiological responses of salt-tolerant/sensitive and heat-tolerant/sensitive tomatoes at control, heat, salt and combined stress were investigated. Based on leaf Fv /Fm and H2 O2 content, samples from tolerant genotype at the four treatments for 36 h were taken for transcriptomics and metabolomics. We found that plant height, dry weight and net photosynthetic rate decreased while leaf Na+ concentration increased in all four genotypes under salt and combined stress than control. Changes in physiological indicators such as photosynthetic parameters and defence enzyme activities in tomato under combined stress were regulated by the expression of relevant genes and the accumulation of key metabolites. We screened five key pathways in tomato responding to a combination of salt and heat stress, such as oxidative phosphorylation (map00190). Synergistic regulation at morphological, physiological, transcriptional and metabolic levels in tomato plants was induced by combined stress. Heat stress was considered as a dominant stressor for tomato plants under the current combined stress. The oxidative phosphorylation pathway played a key role in tomato in response to combined stress, where tapped key genes (e.g. alternative oxidase, Aox1a) need further functional analysis. Our study will provide a valuable resource important for studying stress combination and improving tomato tolerance.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Resposta ao Choque Térmico/genética , Estresse Fisiológico , Fotossíntese , Folhas de Planta/metabolismo
2.
Inorg Chem ; 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39161314

RESUMO

A series of deeply reduced MoIV6-polyoxometalates (POMs), [MoIV6(bpy)6MoVI2O16S2]·10H2O (1) (bpy = 2,2'-bipyridine), [MoIV6(bpy)4(L-TrA)2MoV4(bpy)2O14S4]2·36.5H2O (2), and [MoIV6(bpy)4(D-TrA)2MoV4(bpy)2O14S4]2 (3) (TrA = tartaric acid), were obtained from one-pot hydrothermal syntheses. They feature the bioxo-bridged [MoIV3O3S]4+ incomplete cuboidal cores stabilized by strong triangular metal-metal bonds and datively chelated bpy π-ligands. The two apical MoVIO4 in 12e-Mo8 (1) and two [MoV2O3STrAbpy] in 16e-Mo10 (2, 3) complete the octahedral coordination geometry of the deeply reduced MoIV, not counting the MoIV-MoIV d2-d2 bonds. The aromatic planar bpy π ligands form a two-dimensional face-to-face π stacking supramolecular structure, which are further strengthened by point-to-face C-H···π interactions in the π stacked layers. 16e-Mo10 (2, 3) has stronger intramolecular face-to-face π stacking interactions, which are interconnected by intermolecular C-H···π into a three-dimensional framework structure. These structural features account for their highly enhanced electronic conductivities (1, 6.19 × 10-8 S cm-1; 2, 2.18 × 10-7 S cm-1), providing a new way of thinking to improve electronic conductivity of POMs. 1-3 have been described by first-principles density function theory (DFT) calculations and also characterized by elemental analyses, powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), solid UV-visible spectra, and circular dichroic (CD) spectra.

3.
Inorg Chem ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012053

RESUMO

Ru(PPh3)3Cl2 reacts with Binn- from an ethylenediamine (en) solution of K5Bi4 to yield a new architype of 13-vertex [Bi10{RuPPh3}3]- (1) composed of unprecedented incomplete cuboidal Bi73- and triangular Bi33- held together by {RuPPh3}2+.

4.
Fish Shellfish Immunol ; 152: 109726, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38944254

RESUMO

The immune system of bony fish closely resembles that of mammals, comprising both specific (adaptive) and non-specific (innate) components. Notably, the mucosa-associated lymphoid tissue (MALT) serves as the first line of defense within the non-specific immune system, playing a critical role in protecting these aquatic organisms against invading pathogens. MALT encompasses a network of immune cells strategically distributed throughout the gills and intestines, forming an integral part of the mucosal barrier that interfaces directly with the surrounding aquatic environment. Spring Viremia of Carp Virus(SVCV), a highly pathogenic agent causing substantial harm to common carp populations, has been designated as a Class 2 animal disease by the Ministry of Agriculture and Rural Affairs of China. Utilizing a comprehensive array of research techniques, including Hematoxylin and Eosin (HE)、Alcian Blue Periodic Acid-Schiff (AB-PAS)、transcriptome analysis for global gene expression profiling and Reverse Transcription-Polymerase Chain Reaction (RT-qPCR), this study uncovered several key findings: SVCV is capable of compromising the mucosal architecture in the gill and intestinal tissues of carp, and stimulate the proliferation of mucous cells both in gill and intestinal tissues. Critically, the study revealed that SVCV's invasion elicits a robust response from the carp's mucosal immune system, demonstrating the organism's capacity to resist SVCV invasion despite the challenges posed by the pathogen.


Assuntos
Carpas , Doenças dos Peixes , Perfilação da Expressão Gênica , Brânquias , Intestinos , Infecções por Rhabdoviridae , Rhabdoviridae , Animais , Brânquias/imunologia , Brânquias/virologia , Rhabdoviridae/fisiologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/virologia , Carpas/imunologia , Carpas/genética , Perfilação da Expressão Gênica/veterinária , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/veterinária , Infecções por Rhabdoviridae/virologia , Intestinos/imunologia , Intestinos/virologia , Imunidade Inata/genética , Transcriptoma/imunologia , Imunidade nas Mucosas
5.
Soft Matter ; 19(7): 1342-1347, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36723039

RESUMO

Colloidal gels formed from small attractive particles are commonly used in formulations to keep larger components in suspension. Despite extensive work characterising unfilled gels, little is known about how the larger inclusions alter the phase behavior and microstructure of the colloidal system. Here we use numerical simulations to examine how larger 'granular' particles can alter the gel transition phase boundaries. We find two distinct regimes depending on both the filler size and native gel structure: a 'passive' regime where the filler fits into already-present voids, giving little change in the transition, and an 'active' regime where the filler no longer fits in these voids and instead perturbs the native structure. In this second regime the phase boundary is controlled by an effective colloidal volume fraction given by the available free volume.

6.
Plant Dis ; 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37172976

RESUMO

Blueberry (Vaccinium corymbosum) plants are popular all over the world due to their high nutritional value and health benefits. In October 2020, blueberry stems (cv. O'Neal) displaying reddish brown necrotic lesions were observed from a blueberry field in Anqing (Anhui, China), with the incidence of approximately 90%. The affected plants were somewhat stunted that had smaller fruit, and in severe cases, partial or whole plant died. We randomly selected three sampling sites to collect stems with the symptoms. Samples at the margin between diseased and healthy tissues were taken out, cut into 5 mm pieces in length,and then mixed them together. Twenty small samples were surface-sterilized, and plated onto potato dextrose agar (PDA). The plates were incubated at 25°C in the dark until fungal colonies were observed. After subculturing single hyphal tips, 9 out of 12 fungal isolates with similar morphologies were obtained. The representative isolate, LMKY12 was selected for further identification. The colonies on PDA showed white, fluffy aerial mycelia with 7.9  0.2 mm (n=5) diameter after inoculation in darkness at 25°C for one week. The colony darkens in color with age, yellowish pigmentation in reverse were observed. After 15 days of incubation, dark brown, irregular hard particles (fruiting bodies in sexual stage) accumulated on the surface of the colonies. Asci were 8-spored, sessile, club-like, hyaline, and 35-46 x 6-9 µm (n=30) in size. The ascospores were oval or spindle shaped, two-celled, constricted at division, and containing four guttulates with larger guttules at centre and smaller one at ends, measured 9-11 x 2-4 um (n=50). No sporulation observed on blueberry stems after inoculated 30 days. In order to induce the production of conidiophores, mycelial plugs were placed on blueberry leaves and cultured in darkness at 25°C. There are two types of conidia observed after 20 days of inoculation. Alpha conidia were aseptate, hyaline, smooth, ovate to ellipsoidal, often biguttulate, measured 5.33-7.26 x 1.65-2.53 µm (n=50). Beta conidia were hyaline, linear, measured 12.60-17.91 x 0.81-1.38 µm (n=30). The morphological characteristics matched the previous description of D. sojae (Udayanga et al. 2015; Guo et al. 2020). To confirm the identification, the mycelial genomic DNA of LMKY12 was extracted as a template. The rDNA internal transcribed spacer (ITS), translation elongation factor 1-α gene (TEF1-α), and calmodulin (CAL) were amplified and sequenced using primers ITS1/ITS4 (White et al. 1990), EF1-728F/EF1-986R, and CAL-228F/CAL-737R (Carbone and Kohn 1999), respectively. BLAST analysis revealed that the ITS (ON545758), CAL (OP886852), and TEF1-α (OP886853) sequences were 100% (527/527 base pairs), 99.21% (504/508 base pairs), and 99.41% (336/338 base pairs) similar to the strain FAU636 of D. sojae (KJ590718, KJ612115, KJ590761), respectively. Phylogenetic analysis based on concatenated sequences of ITS, TEF1-α, and CAL using MEGA 7.0 by maximum likelihood attributed the isolate LMKY12 to the D. sojae clade. Pathogenicity tests were performed on blueberry cv. O'Neal using detached stems (n=8) in laboratory, one-year-old potted plants (n=4) in greenhouse. Inoculations were done by placing mycelial plugs (7 mm in diameter) taken from a 7-day-old PDA culture on wounded stems. Inoculations with uncolonized agar plugs served as negative controls. Reddish dark brown lesions similar to the symptoms were observed on all inoculated stems 7 days after inoculation. No symptoms developed on control stems. Reisolations were successfully made from all the inoculated stems, and the pathogen was confirmed by the presence of pycnidia, alpha conidia and beta conidia. To our knowledge, this is the first report of D. sojae causing blueberry stem canker in China.

7.
Opt Lett ; 46(20): 5161-5164, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34653141

RESUMO

Here we demonstrate a red structural color of a multilayer structure made of all silicon-based materials. By using amorphous silicon (a-Si) and silicon dioxide (SiO2) with a large difference in the refractive index, high reflection efficiency can be achieved with only a few layers. The anti-reflection unit composed of top silicon monoxide (SiO) and SiO2 layers can significantly reduce the reflection intensity of the non-target wavelengths to ensure that the device has good color saturation. The selective absorption of SiO and a-Si layers can further improve the color saturation. By reasonably controlling the thickness of the highly absorbing materials, the device has good angular insensitivity at an incident angle of 0°-60°. Furthermore, the angle-insensitive blue and yellow structural colors are also realized based on the all silicon design idea. This scheme is simple in structure and capable of efficient mass production. This method has enormous potential for diverse applications in display, colorful decoration, anti-counterfeiting, and so forth.

8.
Sensors (Basel) ; 21(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202366

RESUMO

In this paper, a fault diagnosis method is proposed based on multi-sensor fusion information for a single fault and composite fault of train braking systems. Firstly, the single mass model of the train brake is established based on operating environment. Then, the pre-allocation and linear-weighted summation criterion are proposed to fuse the monitoring data. Finally, based on the improved expectation maximization, the braking modes and braking parameters are identified, and the braking faults are diagnosed in real time. The simulation results show that the braking parameters of systems can be effectively identified, and the braking faults can be diagnosed accurately based on the identification results. Even if the monitoring data are missing or abnormal, compared with the maximum fusion, the accuracies of parameter identifications and fault diagnoses can still meet the needs of the actual systems, and the effectiveness and robustness of the method can be verified.

9.
Langmuir ; 36(45): 13633-13641, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33147955

RESUMO

Liquid-liquid dispersion coupled with droplet formation and mass transfer of surfactants is one of the most typical phenomena in many chemical processes. As in every aspect of this process, the interfacial tension variation caused by the unsaturated adsorption of surfactants on the droplet surface plays an important role. This article focuses on microdroplet formation and the dynamic interfacial behavior of surfactants in the jetting regime. In a capillary embedded step T-junction device, controllable preparation of monodisperse droplets is achieved, and a correlation for predicting droplet sizes is established. A method for measuring the dynamic interfacial tension is provided. Mass transfer coefficients are then calculated for Tween 20 during the droplet formation process by a semiempirical correlation. The results indicate that dynamic interfacial tensions are lower than those obtained when the surfactant is adsorbed to equilibrium. Based on the tip-streaming phenomenon, mass transfer coefficients for Tween 20 can reach up to ∼10-3 m/s, higher than those obtained in coaxial microfluidic devices. All the preliminary results shed light on the nature of droplet formation and will be of significance for application in industrial apparatuses.

10.
Mikrochim Acta ; 187(7): 402, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32572633

RESUMO

New multi-walled carbon nanotubes supported on Ti3C2-MXene and chitosan (chit) composite film-based electrochemical sensor for ifosfamide (IFO), acetaminophen (ACOP), domperidone (DOM), and sumatriptan (SUM) have been developed. Ti3C2-MXene was synthesized by a fluoride method. Structural and chemical characterizations suggested the successful preparation of Ti3C2-MXene with clearly seen layered morphology, defined 0 0 2 diffraction peak at 7.5° and complete absence of 1 0 4 plane at 39°. The electrochemical performance of the sensor was investigated by cyclic voltammetry and adsorptive stripping differential pulse voltammetry. The Ti3C2/MWCNT/Chit modified glassy carbon electrode exhibits enhanced electrocatalytic activities toward the oxidation of target analytes. Excellent conductivity, large surface area, and high catalytic properties of the Ti3C2-MXene showed synergistic effects with MWCNTs and helped in achieving low detection limits of targets with high selectivity and reproducibility. The assay allows determination of IFO, ACOP, DOM, and SUM in the concentration ranges 0.0011-1.0, 0.0042-7.1, 0.0046-7.3, and 0.0033-61 µM with low detection limits of 0.00031, 0.00028, 0.00034, and 0.00042 µM, respectively. The sensor was successfully applied for voltammetric screening of target analytes in urine and blood serum samples with recoveries > 95.21%. Schematic illustration of the synthesis of self-assembled MXene/MWCNT/chitosan nanocomposite is given and its application to the voltammetric determination of ifosfamide, acetaminophen, domperidone, and sumatriptan described. Graphical abstract.


Assuntos
Quitosana/química , Técnicas Eletroquímicas/métodos , Nanocompostos/química , Nanotubos de Carbono/química , Titânio/química , Acetaminofen/sangue , Acetaminofen/urina , Domperidona/sangue , Domperidona/urina , Humanos , Ifosfamida/sangue , Ifosfamida/urina , Limite de Detecção , Reprodutibilidade dos Testes , Sumatriptana/sangue , Sumatriptana/urina
11.
Soft Matter ; 15(5): 880-889, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30601566

RESUMO

A microfluidic technique recently proposed in the literature to measure the interfacial tension between a liquid droplet and an immiscible suspending liquid [Hudson et al., Appl. Phys. Lett., 2005, 87, 081905], [Cabral and Hudson, Lab Chip, 2006, 6, 427] is suitably adapted to the characterization of the elastic modulus of soft particles in a continuous-flow process. A microfluidic device consisting of a cylindrical pipe with a reduction in cross-section is designed, and the deformation and velocity of incompressible elastic particles suspended in a Newtonian liquid are tracked as they move along the centerline through the constriction. Kinematic and shape information is exploited to calculate the particle's elastic modulus by means of the theory of elastic particle deformation in extensional flow. The approach is validated for different orders of magnitude of the elastic capillary number through experiments and numerical simulations.

12.
Molecules ; 24(10)2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31121976

RESUMO

A new lignan (T4) and three known lignans (T1, T2, and T3) were isolated from the methanol extract of the roots of Phryma leptostachya using bioassay-guided method, and their structures were identified as phrymarolin I (T1), II (T2), haedoxan A (T3), and methyl 4-((6a-acetoxy-4-(6-methoxybenzo[d][1,3]dioxol-5-yl)tetrahydro-1H,3H-furo[3,4-c]furan-1-yl)oxy)-1-hydroxy-2,2-dimethoxy-5-oxocyclopent-3-ene-1-carboxylate (T4) byNMR and ESI-MS spectral data. Bioassay results revealed that haedoxan A exhibited remarkably high insecticidal activity against Mythimna separata with a stomach toxicity LC50 value of 17.06 mg/L and a topical toxicity LC50 value of 1123.14 mg/L at 24 h, respectively. Phrymarolin I and compound T4 also showed some stomach toxicity against M. separata with KD50 values of 3450.21 mg/L at 4 h and 2807.10 mg/L at 8 h, respectively. In addition, phrymarolin I and haedoxan A exhibited some stomach toxicity against Plutella xylostella with an LC50 value of 1432.05 and 857.28 mg/L at 48 h, respectively. In conclusion, this study demonstrated that lignans from P. leptostachya are promising as a novel class of insecticides or insecticide lead compounds for developing botanical pesticides.


Assuntos
Inseticidas/isolamento & purificação , Lamiales/química , Lignanas/isolamento & purificação , Animais , Benzodioxóis/química , Benzodioxóis/isolamento & purificação , Benzodioxóis/farmacologia , Brassica/parasitologia , Inseticidas/química , Inseticidas/farmacologia , Lepidópteros/efeitos dos fármacos , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Extratos Vegetais/química , Triticum/parasitologia
13.
Chemistry ; 24(49): 12912-12919, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-29802660

RESUMO

In this work, a Si@C microsphere composite with multiple buffer structures is prepared by hydrothermal treatment to solve the fatal drawbacks of serious pulverization and low electronic conductivity of Si anodes. By virtue of ferric citrate being the carefully chosen coating carbon source, the silicon nanoparticles with a SiOx layer are encapsulated by the homogeneous mesoporous carbon layer. The SiOx layer with appropriate toughness can primarily suppress the volume expansion of silicon. The plentiful mesopores in the carbon layer and the framework formed by carbon nanotubes with good mechanical strength can effectively buffer and accommodate the volume change of silicon, and greatly improve the infiltration of the electrolyte to the anode. Meanwhile, the mesoporous carbon and carbon nanotube network also enhance the conductivity of the composite. Therefore, the Si@C electrodes exhibit a high initial charge/discharge capacity of 2956/4197 mAh g-1 at a current density of 0.42 A g-1 , excellent rate capability, and outstanding cycle performance up to 800 cycles by virtue of the multiple buffer structures.

14.
Anal Chem ; 89(12): 6309-6313, 2017 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-28537722

RESUMO

An in situ micro-MEA technique, which could precisely measure the performance of ORR electrocatalyst using Nafion as electrolyte, was designed and compared with regular thin-film rotating-disk electrode (TFRDE) (0.1 M HClO4) and normal in situ membrane electrode assembly (MEA) tests. Compared to the traditional TFRDE method, the micro-MEA technique makes the acquisition of catalysts' behavior at low potential values easily achieved without being limited by the solubility of O2 in water. At the same time, it successfully mimics the structure of regular MEAs and obtains similar results to a regular MEA, thus providing a new technique to simply measure the electrode activity without being bothered by complicated fabrication of regular MEA. In order to further understand the importance of in situ measurement, Fe-N-C as a typical oxygen reduction reaction (ORR) free-Pt catalyst was evaluated by TFRDE and micro-MEA. The results show that the half wave potential of Fe-N-C only shifted negatively by -135 mV in comparison with state-of-the-art Pt/C catalysts from TFRDE tests. However, the active site density, mass transfer of O2, and the proton transfer conductivity are found to strongly influence the catalyst activity in the micro-MEA, thereby resulting in a much lower limiting current density than Pt/C (8.7 times lower). Hence, it is suggested that the micro-MEA is better in evaluating the in situ ORR performance, where the catalysts are characterized more thoroughly in terms of intrinsic activity, active site density, proton transfer, and mass transfer properties.

15.
Int J Biol Macromol ; 273(Pt 1): 132872, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38942671

RESUMO

Diseases caused by viruses pose a significant risk to the health of aquatic animals, for which there are presently no efficacious remedies. Interferon (IFN) serving as an antiviral agent, is frequently employed in clinical settings. Due to the unique living conditions of aquatic animals, traditional injection of interferon is cumbersome, time-consuming and labor-intensive. This study aimed to prepare IFN microcapsules through emulsion technique by using resistant starch (RS) and carboxymethyl chitosan (CMCS). Optimization was achieved using the Box-Behnken design (BBD) response surface technique, followed by the creation of microcapsules through emulsification. With RS at a concentration of 1.27 %, a water­oxygen ratio of 3.3:7.4, CaCl2 at 13.67 %, CMCS at 1.04 %, the rate of encapsulation can escalate to 80.92 %. Rainbow trout infected with Infectious hematopoietic necrosis virus (IHNV) and common carp infected with Spring vireemia (SVCV) exhibited a relative survival rate (RPS) of 65 % and 60 % after treated with IFN microcapsules, respectively. Moreover, the microcapsules effectively reduced the serum AST levels and enhanced the expression of IFNα, IRF3, ISG15, MX1, PKR and Viperin in IHNV-infected rainbow trout and SVCV-infected carp. In conclusion, this integrated IFN microcapsule showed potential as an antiviral agent for treatment of viral diseases in aquaculture.


Assuntos
Interferon-alfa , Oncorhynchus mykiss , Proteínas Recombinantes , Animais , Oncorhynchus mykiss/virologia , Interferon-alfa/farmacologia , Proteínas Recombinantes/farmacologia , Cápsulas , Antivirais/farmacologia , Antivirais/química , Composição de Medicamentos , Quitosana/química , Quitosana/análogos & derivados , Vírus da Necrose Hematopoética Infecciosa/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Doenças dos Peixes/virologia , Doenças dos Peixes/tratamento farmacológico
16.
Antioxidants (Basel) ; 13(4)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38671895

RESUMO

Under natural conditions, abiotic stresses that limit plant growth and development tend to occur simultaneously, rather than individually. Due to global warming and climate change, the frequency and intensity of heat and salt stresses are becoming more frequent. Our aim is to determine the response mechanisms of tomato to different intensities of combined heat and salt stresses. The physiological and morphological responses and photosynthesis/reactive oxygen species (ROS)-related genes of tomato plants were compared under a control, heat stress, salt stress (50/100/200/400 mM NaCl), and a combination of salt and heat stresses. The stomatal conductance (gs) of tomato leaves significantly increased at a heat + 50 mM NaCl treatment on day 4, but significantly decreased at heat + 100/200/400 mM NaCl treatments, compared with the control on days 4 and 8. The O2·- production rate of tomato plants was significantly higher at heat + 100/200/400 mM NaCl than the control, which showed no significant difference between heat + 50 mM NaCl treatment and the control on days 4 and 8. Ascorbate peroxidase 2 was significantly upregulated by heat + 100/200/400 mM NaCl treatment as compared with heat + 50 mM NaCl treatment on days 4 and 8. This study demonstrated that the dominant effect ratio of combined heat and salt stress on tomato plants can shift from heat to salt, when the intensity of salt stress increased from 50 mM to 100 mM or above. This study provides important information for tomato tolerance improvement at combined heat and salt stresses.

17.
Foods ; 12(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36673425

RESUMO

Culinary circles have experienced a recent trend towards low-salt hotpot sauces. Here, changes in the physicochemical quality, flavour, and bacterial diversity of hotpot sauces with different salt concentrations were studied during storage. The results indicated that the peroxide and acid values of hotpot sauce increased gradually and that the quality began to deteriorate with storage. A storage temperature of 4 °C and salt concentration above 4.4% significantly reduced spoilage. The salt concentration had no significant effect on the flavour but extended storage resulted in significant differences in flavour reflected in the changes of sweet, sour, bitter, umami, aftertaste-A, abundance, organic sulphide, and alkanes. Significant differences were found in the bacterial composition between samples stored at different temperatures. Norank-f-o-Chloroplast was the main bacterium in the samples stored at low temperatures, which was beneficial for preservation. Bacillus was detected in 4.1% NaCl samples stored at 25 °C, directly promoting sauce spoilage and an unpleasant flavour. This bacterium signalled the spoilage of low-salt hotpot sauce stored at room temperature.

18.
Food Chem ; 423: 136245, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37201256

RESUMO

Biosynthesis is the safest method for preparing GABA; however, there are not enough GABA-producing strains to provide an effective resource. The purpose of this study was to determine the feasibility of using Lactobacillus fermentum SMN10-3(A) and Lactococcus lactis SMN15-6(B) to study the effects of strain complex pairing on the GABA formation, flavour, and metabolic pathways of fermented soymilk. It was found that group A2B1 had the highest acid production rate, GABA yield (1.76 ± 0.01 mg/mL), and flavour compound content. A total of 55 differential metabolites were produced after fermentation, of which 28 dominated by hexanal were significantly downregulated and 26 dominated by alcohols were significantly upregulated. The significant metabolic pathways involved were d-alanine, taurine and hypotaurine, and selenocompound metabolism. Finally, the components contributing to the aroma of fermented soymilk were identified, which included 2-pentylfuran and 2-butyl-2-octenal. These results provide a theoretical basis for future research on GABA-rich fermented foods.


Assuntos
Alimentos Fermentados , Leite de Soja , Fermentação , Leite de Soja/química , Ácido gama-Aminobutírico/metabolismo
19.
Front Plant Sci ; 14: 1238108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37701806

RESUMO

With global climate change, the frequency and intensity of waterlogging events are increasing due to frequent and heavy precipitation. Little is known however about the response of plants to repeated waterlogging stress events. The aim is to clarify physiological regulation mechanisms of tomato plants under repeated waterlogging stress, and whether Trichoderma harzianum can alleviate waterlogging injury. We identified two genotypes of tomato, 'MIX-002' and 'LA4440', as waterlogging tolerant and sensitive genotypes, respectively, based on plant biomass accumulation. The two tomato genotypes were subjected to a waterlogging priming treatment for 2 days (excess water for 1 cm above substrate surface) followed by a recovery stage for 2 days, and then a second waterlogging stress for 5 days (excess water for 1 cm above substrate surface) followed by a second recovery stage for 3 days. Leaf physiological, plant growth parameters, and the expression of five key genes were investigated. We found that the two genotypes responded differently to waterlogging priming and stress in terms of photosynthesis, reactive oxygen species (ROS), and osmotic regulatory mechanisms. Waterlogging stress significantly increased H2O2 content of 'MIX-002', while that of 'LA4440' had no significant change. Under waterlogging stress, photosynthesis of the two genotypes treated with waterlogging priming returned to the control level. However, Trichoderma harzianum treatment during the second recovery stage did not show positive mitigative effects. The plants of 'LA4440' with priming showed lower peroxidase (POD) activity and proline content but higher H2O2 content than that without priming under waterlogging stress. Under waterlogging stress with priming as compared to without priming, SODCC2 was downregulated in two tomatoes, and AGR2 and X92888 were upregulated in 'MIX-002' but downregulated in 'LA4440'. Overall, the two tomato genotypes exhibited distinct photosynthetic, ROS and osmotic regulatory mechanisms responding to the waterlogging stress. Waterlogging priming can induce stress memory by adjusting stomatal conductance, sustaining ROS homeostasis, regulating osmotic regulatory substances and key gene expressions mediated by H2O2, and thus alleviate the damage on tomato photosynthesis when waterlogging reoccurred.

20.
Accid Anal Prev ; 165: 106506, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34890921

RESUMO

Accurately determining a train's state is essential for passenger safety, operation efficiency, and maintenance. However, the actual operation state of a train is composed of a variety of modes and is disturbed by several known or unknown factors, for which an accurate estimator is required. Hence, in this paper, a train multi-mode model considering the actual operation environment is established, and a train state estimation method based on multi-sensor parallel fusion filter is proposed. In the parallel fusion filter, the current mode of train is determined by the proposed sliding window error and voting mechanism, and the global filter are constituted by the local filters, which are fused by linear-weighted summation. The simulation results demonstrate the effectiveness of our method in estimating the train's state. It is worth noting that even if monitoring data are missing or are abnormal, the state estimation accuracy of the proposed technique still meets the requirements of a real system, and the effectiveness and robustness of the method can be verified.


Assuntos
Acidentes de Trânsito , Algoritmos , Simulação por Computador , Humanos
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