Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 104
Filtrar
1.
Eval Health Prof ; : 1632787241246130, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38598289

RESUMEN

This study aimed to develop and validate a new scale to measure health problem prevention and control strategies employed by medical rescuers fighting epidemics. In Study I, a qualitative study, focus group discussion, and expert panel review were conducted to generate items that capture components of prevention and control strategies. In Study II, exploratory factor analysis was used to examine the scale's structure. In Study III, the scale's validity and reliability were assessed via confirmatory factor analysis, average variance extracted, composite reliability, and Cronbach's α. Data analysis was performed using Nvivo 12.0, SPSS 25.0, and Amos 23.0. The final scale was divided into three subscales (comprising 5 factors and 18 items on the Before Medical Rescue subscale, 6 factors and 28 items on the During Medical Rescue subscale, and 4 factors and 14 items on the After Medical Rescue subscale). The scale has excellent validity and reliability and can be used to measure the health problem prevention and control strategies of medical rescuers fighting epidemics.

2.
Nat Plants ; 10(4): 661-672, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38589484

RESUMEN

Carboxysomes are bacterial microcompartments that encapsulate the enzymes RuBisCO and carbonic anhydrase in a proteinaceous shell to enhance the efficiency of photosynthetic carbon fixation. The self-assembly principles of the intact carboxysome remain elusive. Here we purified α-carboxysomes from Prochlorococcus and examined their intact structures using single-particle cryo-electron microscopy to solve the basic principles of their shell construction and internal RuBisCO organization. The 4.2 Å icosahedral-like shell structure reveals 24 CsoS1 hexamers on each facet and one CsoS4A pentamer at each vertex. RuBisCOs are organized into three concentric layers within the shell, consisting of 72, 32 and up to 4 RuBisCOs at the outer, middle and inner layers, respectively. We uniquely show how full-length and shorter forms of the scaffolding protein CsoS2 bind to the inner surface of the shell via repetitive motifs in the middle and C-terminal regions. Combined with previous reports, we propose a concomitant 'outside-in' assembly principle of α-carboxysomes: the inner surface of the self-assembled shell is reinforced by the middle and C-terminal motifs of the scaffolding protein, while the free N-terminal motifs cluster to recruit RuBisCO in concentric, three-layered spherical arrangements. These new insights into the coordinated assembly of α-carboxysomes may guide the rational design and repurposing of carboxysome structures for improving plant photosynthetic efficiency.

3.
J Proteomics ; 299: 105145, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38431086

RESUMEN

Mesembryanthemum crystallinum (common ice plant), a facultative CAM plant, shifts from C3 to CAM photosynthesis under salt stress, enhancing water use efficiency. Here we used transcriptomics, proteomics, and targeted metabolomics to profile molecular changes during the diel cycle of C3 to CAM transition. The results confirmed expected changes associated with CAM photosynthesis, starch biosynthesis and degradation, and glycolysis/gluconeogenesis. Importantly, they yielded new discoveries: 1) Transcripts displayed greater circadian regulation than proteins. 2) Oxidative phosphorylation and inositol methylation may play important roles in initiating the transition. 3) V-type H+-ATPases showed consistent transcriptional regulation, aiding in vacuolar malate uptake. 4) A protein phosphatase 2C, a major component in the ABA signaling pathway, may trigger the C3 to CAM transition. Our work highlights the potential molecular switches in the C3 to CAM transition, including the potential role of ABA signaling. SIGNIFICANCE: The common ice plant is a model facultative CAM plant, and under stress conditions it can shift from C3 to CAM photosynthesis within a three-day period. However, knowledge about the molecular changes during the transition and the molecular switches enabling the transition is lacking. Multi-omic analyses not only revealed the molecular changes during the transition, but also highlighted the importance of ABA signaling, inositol methylation, V-type H+-ATPase in initiating the shift. The findings may explain physiological changes and nocturnal stomatal opening, and inform future synthetic biology effort in improving crop water use efficiency and stress resilience.


Asunto(s)
Mesembryanthemum , Fotosíntesis , Fotosíntesis/fisiología , Mesembryanthemum/metabolismo , Multiómica , Plantas , Inositol/metabolismo , Agua/metabolismo
4.
Biotechnol Biofuels Bioprod ; 17(1): 26, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38360745

RESUMEN

The cultivation of microalgae and microalgae-bacteria consortia provide a potential efficient strategy to fix CO2 from waste gas, treat wastewater and produce value-added products subsequently. This paper reviews recent developments in CO2 fixation and wastewater treatment by single microalgae, mixed microalgae and microalgae-bacteria consortia, as well as compares and summarizes the differences in utilizing different microorganisms from different aspects. Compared to monoculture of microalgae, a mixed microalgae and microalgae-bacteria consortium may mitigate environmental risk, obtain high biomass, and improve the efficiency of nutrient removal. The applied microalgae include Chlorella sp., Scenedesmus sp., Pediastrum sp., and Phormidium sp. among others, and most strains belong to Chlorophyta and Cyanophyta. The bacteria in microalgae-bacteria consortia are mainly from activated sludge and specific sewage sources. Bioengineer in CBB cycle in microalgae cells provide effective strategy to achieve improvement of CO2 fixation or a high yield of high-value products. The mechanisms of CO2 fixation and nutrient removal by different microbial systems are also explored and concluded, the importance of microalgae in the technology is proven. After cultivation, microalgae biomass can be harvested through physical, chemical, biological and magnetic separation methods and used to produce high-value by-products, such as biofuel, feed, food, biochar, fertilizer, and pharmaceutical bio-compounds. Although this technology has brought many benefits, some challenging obstacles and limitation remain for industrialization and commercializing.

5.
Sensors (Basel) ; 24(4)2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38400446

RESUMEN

This study presents a machine vision-based variable weeding system for plant- protection unmanned ground vehicles (UGVs) to address the issues of pesticide waste and environmental pollution that are readily caused by traditional spraying agricultural machinery. The system utilizes fuzzy rules to achieve adaptive modification of the Kp, Ki, and Kd adjustment parameters of the PID control algorithm and combines them with an interleaved period PWM controller to reduce the impact of nonlinear variations in water pressure on the performance of the system, and to improve the stability and control accuracy of the system. After testing various image threshold segmentation and image graying algorithms, the normalized super green algorithm (2G-R-B) and the fast iterative threshold segmentation method were adopted as the best combination. This combination effectively distinguished between the vegetation and the background, and thus improved the accuracy of the pixel extraction algorithm for vegetation distribution. The results of orthogonal testing by selected four representative spraying duty cycles-25%, 50%, 75%, and 100%-showed that the pressure variation was less than 0.05 MPa, the average spraying error was less than 2%, and the highest error was less than 5% throughout the test. Finally, the performance of the system was comprehensively evaluated through field trials. The evaluation showed that the system was able to adjust the corresponding spraying volume in real time according to the vegetation distribution under the decision-making based on machine vision algorithms, which proved the low cost and effectiveness of the designed variable weed control system.

6.
Nat Struct Mol Biol ; 31(2): 293-299, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38177666

RESUMEN

Transcription factors respond to multilevel stimuli and co-occupy promoter regions of target genes to activate RNA polymerase (RNAP) in a cooperative manner. To decipher the molecular mechanism, here we report two cryo-electron microscopy structures of Anabaena transcription activation complexes (TACs): NtcA-TAC composed of RNAP holoenzyme, promoter and a global activator NtcA, and NtcA-NtcB-TAC comprising an extra context-specific regulator, NtcB. Structural analysis showed that NtcA binding makes the promoter DNA bend by ∼50°, which facilitates RNAP to contact NtcB at the distal upstream NtcB box. The sequential binding of NtcA and NtcB induces looping back of promoter DNA towards RNAP, enabling the assembly of a fully activated TAC bound with two activators. Together with biochemical assays, we propose a 'DNA looping' mechanism of cooperative transcription activation in bacteria.


Asunto(s)
Proteínas Bacterianas , Compuestos Nitrosos , Tiazolidinas , Tiocianatos , Transactivadores , Transactivadores/genética , Activación Transcripcional , Microscopía por Crioelectrón , Secuencia de Bases , Proteínas Bacterianas/metabolismo , ARN Polimerasas Dirigidas por ADN/metabolismo , Transcripción Genética , Regulación Bacteriana de la Expresión Génica
7.
Aging Dis ; 15(1): 115-152, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37307828

RESUMEN

As a recently discovered waste removal system in the brain, cerebral lymphatic system is thought to play an important role in regulating the homeostasis of the central nervous system. Currently, more and more attention is being focused on the cerebral lymphatic system. Further understanding of the structural and functional characteristics of cerebral lymphatic system is essential to better understand the pathogenesis of diseases and to explore therapeutic approaches. In this review, we summarize the structural components and functional characteristics of cerebral lymphatic system. More importantly, it is closely associated with peripheral system diseases in the gastrointestinal tract, liver, and kidney. However, there is still a gap in the study of the cerebral lymphatic system. However, we believe that it is a critical mediator of the interactions between the central nervous system and the peripheral system.


Asunto(s)
Sistema Nervioso Central , Sistema Linfático , Encéfalo/fisiología , Homeostasis
9.
J Adv Res ; 2023 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-37956859

RESUMEN

BACKGROUND: The breeding of high-quality, high-yield, and disease-resistant varieties is closely related to food security. The investigation of breeding results relies on the evaluation of seed phenotype, which is a key step in the process of breeding. In the global digitalization trend, digital technology based on optical sensors can perform the digitization of seed phenotype in a non-contact, high throughput way, thus significantly improving breeding efficiency. AIM OF REVIEW: This paper provides a comprehensive overview of the principles, characteristics, data processing methods, and bottlenecks associated with three digital technique types based on optical sensors: spectroscopy, digital imaging, and three-dimensional (3D) reconstruction techniques. In addition, the applicability and adaptability of digital techniques based on the optical sensors of maize seed phenotype traits, namely external visible phenotype (EVP) and internal invisible phenotype (IIP), are investigated. Furthermore, trends in future equipment, platform, phenotype data, and processing algorithms are discussed. This review offers conceptual and practical support for seed phenotype digitization based on optical sensors, which will provide reference and guidance for future research. KEY SCIENTIFIC CONCEPTS OF REVIEW: The digital techniques based on optical sensors can perform non-contact and high-throughput seed phenotype evaluation. Due to the distinct characteristics of optical sensors, matching suitable digital techniques according to seed phenotype traits can greatly reduce resource loss, and promote the efficiency of seed evaluation as well as breeding decision-making. Future research in phenotype equipment and platform, phenotype data, and processing algorithms will make digital techniques better meet the demands of seed phenotype evaluation, and promote automatic, integrated, and intelligent evaluation of seed phenotype, further helping to lessen the gap between digital techniques and seed phenotyping.

10.
Molecules ; 28(21)2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37959701

RESUMEN

Pyrolysis and activation processes are important pathways to utilize residues after lipid extraction from microalgae in a high-value way. The obtained microalgae-based nitrogen-doped activated carbon has excellent electrochemical performance. It has the advantage of nitrogen self-doping using high elemental nitrogen in microalgae. In this study, two kinds of microalgae, Nanochloropsis and Chlorella, were used as feedstock for lipid extraction. The microalgae residue was firstly pyrolyzed at 500 °C to obtain biochar. Then, nitrogen-doped activated carbons were synthesized at an activation temperature of 700-900 °C with different ratios of biochar and KOH (1:1, 1:2, and 1:4). The obtained carbon materials presented rich nitrogen functional groups, including quaternary-N, pyridine-N-oxide, pyrrolic-N, and pyridinic-N. The nitrogen content of microalgae-based activated carbon material was up to 2.62%. The obtained materials had a specific surface area of up to 3186 m2/g and a pore volume in the range of 0.78-1.54 cm3/g. The microporous pore sizes of these materials were distributed at around 0.4 nm. Through electrochemical testing such as cyclic voltammetry and galvanostatic charge-discharge of materials, the materials exhibited good reversibility and high charge-discharge efficiency. The sample, sourced from microalgae Chlorella residue at activation conditions of 700 °C and biochar/KOH = 1:4, exhibited excellent endurance of 94.1% over 5000 cycles at 2 A/g. Its high specific capacitance was 432 F/g at 1 A/g.


Asunto(s)
Chlorella , Microalgas , Carbón Orgánico , Nitrógeno/química , Pirólisis , Lípidos
11.
Crit Rev Food Sci Nutr ; : 1-17, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37983168

RESUMEN

To meet the growing demand for food quality and safety, there is a pressing need for fast and visible techniques to monitor the food crop and product production processing, and to understand the chemical changes that occur during these processes. Herein, the fundamental principles, instruments, and characteristics of three major laser-based imaging techniques (LBITs), namely, laser-induced breakdown spectroscopy, Raman spectroscopy, and laser ablation-inductively coupled plasma-mass spectrometry, are introduced. Additionally, the advances, challenges, and prospects for the application of LBITs in food crops and products are discussed. In recent years, LBITs have played a crucial role in mapping primary metabolites, secondary metabolites, nanoparticles, toxic metals, and mineral elements in food crops, as well as visualizing food adulteration, composition changes, pesticide residue, microbial contamination, and elements in food products. However, LBITs are still facing challenges in achieving accurate and sensitive quantification of compositions due to the complex sample matrix and minimal laser sampling quantity. Thus, further research is required to develop comprehensive data processing strategies and signal enhancement methods. With the continued development of imaging methods and equipment, LBITs have the potential to further explore chemical distribution mechanisms and ensure the safety and quality of food crops and products.

12.
Chemosphere ; 345: 140398, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37844705

RESUMEN

Chlorella vulgaris (C. vulgaris) can provide the means to fix CO2 from complicated flue gas, treat wastewater and reach a sustainable production of petrochemical substitutes simultaneously. However, a prerequisite to achieving this goal is to promote C. vulgaris growth and improve the CO2-to-fatty acids conversion efficiency under different conditions of flue gas and wastewater. Thus, the addition of indole-3-acetic acid (IAA) in C. vulgaris cultivation was proposed. Results showed that C. vulgaris were more easily inhibited by 100 ppm NO and 200 ppm SO2 under low nitrogen (N) condition. NO and SO2 decreased the carbon (C) fixation; but increased N and sulfur (S) fixation. IAA adjusted the content of superoxide dismutase (SOD) and malondialdehyde (MDA), improved the expression of psbA, rbcL, and accD, attenuated the toxicity of NO and SO2 on C. vulgaris, and ultimately improved cell growth (2014.64-2458.16 mgdw·L-1) and restored CO2 fixation rate (170.98-220.92 mg CO2·L-1·d-1). Moreover, wastewater was found to have a high treatment efficiency because C. vulgaris grew well in all treatments, and the maximal removal rates of both N and phosphorus (P) reached 100%. Metabonomic analysis showed that IAA, "NO and SO2" were involved in the down-regulated and up-regulated expression of multiple metabolites, such as fatty acids, amino acids, and carbohydrates. IAA was beneficial for improving lipid accumulation with 24584.21-27634.23 µg g-1, especially monounsaturated fatty acids (MUFAs) dominated by 16-18 C fatty acids, in C. vulgaris cells. It was concluded that IAA enhanced the CO2 fixation, fatty acids production of C. vulgaris and its nutrients removal rate.


Asunto(s)
Chlorella vulgaris , Microalgas , Purificación del Agua , Chlorella vulgaris/metabolismo , Aguas Residuales , Lípidos , Reguladores del Crecimiento de las Plantas/metabolismo , Dióxido de Carbono/metabolismo , Ácidos Grasos/metabolismo , Metaboloma , Biomasa , Microalgas/metabolismo
13.
Artículo en Inglés | MEDLINE | ID: mdl-37878686

RESUMEN

MXene is a highly latent capacity electrode material for supercapacitors, but its capacity limits its development. Herein, we have constructed an independently cross-linked three-dimensional (3D) Ti3C2TX MXene film (Zn-A-MXene) with a hydroxylation surface through a zinc ion (Zn2+) and NaOH. The alkalization of NaOH is used to replace the -F functional group that is not conducive to electrochemical reactions and cross-link the MXene nanosheets through the electrostatic interaction of zinc ions. The synergistic effect can greatly improve the effective area of the electrode, the accessibility of the electrolyte, and the specific capacitance. The 3D Zn-A-MXene films exhibit an extremely high capacity (465.1 F g-1 at 1 A g-1). The all-solid-state flexible supercapacitor assembled using a 3D Zn-A-MXene thin film also has a high energy density of 9.55 Wh kg at a power density of 603.16 W kg. After 5000 cycles, the flexible supercapacitor still has 81.25% of its initial capacity, demonstrating good cycling stability. This work furnishes the innovative idea for constructing high-capacity MXene flexible supercapacitors.

14.
Int J Anal Chem ; 2023: 5722131, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37304842

RESUMEN

Materials and Methods: The metabolomics-proteomics of sixty patients with T2DM were acquired by high-performance liquid chromatography (HPLC). In addition, some clinical features, containing total cholesterol (TC), triglycerides (TG), hemoglobin A1c (HbA1c), body mass index (BMI), and low-density lipoprotein (LDL) together with high-density lipoprotein (HDL), were determined via clinical detection strategies. Abundant metabolites and proteins, respectively, were identified with the analysis of liquid chromatography tandem mass spectrometry (LC-MS/MS). Results: 22 differentially abundant metabolites and 15 differentially abundant proteins were determined. The analysis of bioinformatics suggested that the differentially abundant proteins were commonly associated with the renin-angiotensin system, vitamin digestion and absorption, hypertrophic cardiomyopathy, and so on. Furthermore, differentially abundant metabolites were amino acids and were associated with the biosynthesis of CoA and pantothenate, together with the metabolisms of phenylalanine, beta-alanine, proline, and arginine. Combination analysis revealed that the vitamin metabolism pathway was predominantly affected. Conclusions: DHS syndrome can be separated by certain metabolic-proteomic differences, and metabolism is particularly prominent, especially in vitamin digestion and absorption. From the molecular level, we provide preliminary data for the extensive application of TCM in the study of T2DM, and at the same time benefited in a sense diagnosis and treatment of T2DM.

15.
Opt Lett ; 48(13): 3567-3570, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37390182

RESUMEN

In this Letter, a rapid origin classification device and method for Baishao (Radix Paeoniae Alba) slices based on auto-focus laser-induced breakdown spectroscopy (LIBS) is proposed. The enhancement of spectral signal intensity and stability through auto-focus was investigated, as were different preprocessing methods, with area normalization (AN) achieving the best results-increasing by 7.74%-but unable to replace the improved spectral signal quality provided by auto-focus. A residual neural network (ResNet) was used as both a classifier and feature extractor, achieving higher classification accuracy than traditional machine learning methods. The effectiveness of auto-focus was elucidated by extracting LIBS features from the last pooling layer output using uniform manifold approximation and projection (UMAP). Our approach demonstrated that auto-focus could efficiently optimize the LIBS signal, providing broad prospects for rapid origin classification of traditional Chinese medicines.


Asunto(s)
Aprendizaje Automático , Redes Neurales de la Computación , Análisis Espectral , Rayos Láser
16.
Int J Mol Sci ; 24(12)2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37372941

RESUMEN

Plants have evolved diverse strategies to accommodate saline environments. More insights into the knowledge of salt stress regulatory pathways will benefit crop breeding. RADICAL-INDUCED CELL DEATH 1 (RCD1) was previously identified as an essential player in salt stress response. However, the underlying mechanism remains elusive. Here, we unraveled that Arabidopsis NAC domain-containing protein 17 (ANAC017) acts downstream of RCD1 in salt stress response, and its ER-to-nucleus transport is triggered by high salinity. Genetic and biochemical evidence showed that RCD1 interacts with transmembrane motif-truncated ANAC017 in the nucleus and represses its transcriptional activity. Transcriptome analysis revealed that genes associated with oxidation reduction process and response to salt stress are similarly dysregulated in loss-of-function rcd1 and gain-of-function anac017-2 mutants. In addition, we found that ANAC017 plays a negative role in salt stress response by impairing the superoxide dismutase (SOD) enzyme activity. Taken together, our study uncovered that RCD1 promotes salt stress response and maintains ROS homeostasis by inhibiting ANAC017 activity.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Estrés Fisiológico/genética , Fitomejoramiento , Tolerancia a la Sal/genética , Muerte Celular , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Factores de Transcripción/metabolismo
17.
Front Pharmacol ; 14: 1133560, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37007028

RESUMEN

Background: Patients diagnosed with influenza and upper respiratory tract infections (URTIs) have similar clinical manifestations and biochemical indices and a low detection rate of viral pathogens, mixed infection with diverse respiratory viruses, and targeted antiviral treatment difficulty in the early stage. According to the treatment strategy of "homotherapy for heteropathy" in traditional Chinese medicine (TCM), different diseases with the same clinical symptoms can be treated with the same medicines. Qingfei Dayuan granules (QFDY), a type of Chinese herbal preparation included in the TCM Diagnosis and Treatment Protocol for COVID-19 of Hubei Province issued by the Health Commission of Hubei Province in 2021, are recommended for patients suffering from COVID-19 with symptoms of fever, cough, and fatigue, among others. Additionally, recent studies have shown that QFDY effectively alleviates fever, cough, and other clinical symptoms in patients with influenza and URTIs. Materials and methods: The study was designed as a multicenter, randomized, double-blind, placebo-controlled clinical trial for treatment for influenza and URTIs manifested by pulmonary heat-toxin syndrome (PHTS) with QFDY. A total of 220 eligible patients were enrolled from eight first-class hospitals in five cities of Hubei Province in China and randomly assigned to receive either 15 g of QFDY or a placebo three times a day for 5 days. The primary outcome was the complete fever relief time. Secondary outcomes included efficacy evaluation of TCM syndromes, scores of TCM syndromes, cure rate of each single symptom, incidence of comorbidities and progression to severe conditions, combined medications, and laboratory tests. Safety evaluations mainly involved adverse events (AEs) and changes in vital signs during the study. Results: Compared with the placebo group, the complete fever relief time was shorter in the QFDY group, 24 h (12.0, 48.0) in the full analysis set (FAS) and 24 h (12.0, 49.5) in the per-protocol set (PPS) (p ≤ 0.001). After a 3-day treatment, the clinical recovery rate (22.3% in the FAS and 21.6% in the PPS) and cure rate of cough (38.6% in the FAS and 37.9% in the PPS), a stuffy and running nose, and sneezing (60.0% in the FAS and 59.5% in the PPS) in the QFDY group were higher than those in the placebo group (p < 0.05). The number of patients taking antibiotics for more than 24 h in the placebo group (nine cases) was significantly higher than that in the QFDY group (one case) (p < 0.05). There were no significant differences between the two groups in terms of scores of TCM syndromes, incidence of comorbidities or progression to severe conditions, combined use of acetaminophen tablets or phlegm-resolving medicines, and laboratory tests (p > 0.05). Meanwhile, no significant difference was found in the incidence of AEs and vital signs between the two groups (p > 0.05). Conclusion: The trial showed that QFDY was an effective and safe treatment modality for influenza and URTIs manifested by PHTS because it shortened the complete fever relief time, accelerated clinical recovery, and alleviated symptoms such as cough, a stuffy and running nose, and sneezing during the course of treatment. Clinical trial registration: https://www.chictr.org.cn/showproj.aspx?proj=131702, identifier ChiCTR2100049695.

18.
Molecules ; 28(8)2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37110593

RESUMEN

Fast detection of heavy metals is important to ensure the quality and safety of herbal medicines. In this study, laser-induced breakdown spectroscopy (LIBS) was applied to detect the heavy metal content (Cd, Cu, and Pb) in Fritillaria thunbergii. Quantitative prediction models were established using a back-propagation neural network (BPNN) optimized using the particle swarm optimization (PSO) algorithm and sparrow search algorithm (SSA), called PSO-BP and SSA-BP, respectively. The results revealed that the BPNN models optimized by PSO and SSA had better accuracy than the BPNN model without optimization. The performance evaluation metrics of the PSO-BP and SSA-BP models were similar. However, the SSA-BP model had two advantages: it was faster and had higher prediction accuracy at low concentrations. For the three heavy metals Cd, Cu and Pb, the prediction correlation coefficient (Rp2) values for the SSA-BP model were 0.972, 0.991 and 0.956; the prediction root mean square error (RMSEP) values were 5.553, 7.810 and 12.906 mg/kg; and the prediction relative percent deviation (RPD) values were 6.04, 10.34 and 4.94, respectively. Therefore, LIBS could be considered a constructive tool for the quantification of Cd, Cu and Pb contents in Fritillaria thunbergii.


Asunto(s)
Fritillaria , Metales Pesados , Fritillaria/química , Cadmio , Plomo , Metales Pesados/análisis , Análisis Espectral/métodos , Algoritmos , Rayos Láser
19.
Front Plant Sci ; 14: 1128300, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37025139

RESUMEN

Herbs have been used as natural remedies for disease treatment, prevention, and health care. Some herbs with functional properties are also used as food or food additives for culinary purposes. The quality and safety inspection of herbs are influenced by various factors, which need to be assessed in each operation across the whole process of herb production. Traditional analysis methods are time-consuming and laborious, without quick response, which limits industry development and digital detection. Considering the efficiency and accuracy, faster, cheaper, and more environment-friendly techniques are highly needed to complement or replace the conventional chemical analysis methods. Infrared (IR) and Raman spectroscopy techniques have been applied to the quality control and safety inspection of herbs during the last several decades. In this paper, we generalize the current application using IR and Raman spectroscopy techniques across the whole process, from raw materials to patent herbal products. The challenges and remarks were proposed in the end, which serve as references for improving herb detection based on IR and Raman spectroscopy techniques. Meanwhile, make a path to driving intelligence and automation of herb products factories.

20.
Molecules ; 28(6)2023 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-36985748

RESUMEN

Laser-induced breakdown spectroscopy (LIBS) shows promising applications in the analysis of environmental heavy metals. However, direct analysis in water by LIBS faces the problems of droplet splashing and laser energy decay. In this study, a novel liquid-solid conversion method based on agarose films is proposed to provide an easy-to-operate and sensitive detection of heavy metals. First, the water samples were converted into semi-solid hydrogels with the aid of agarose and then dried into agarose films to make the signal intensities stronger. The calibration curves of Cd, Pb and Cr were constructed. The proposed method was validated by standard heavy metal solutions and real water samples. The results showed that the values of R2 were 0.990, 0.989 and 0.975, and the values of the LOD were 0.011, 0.122 and 0.118 mg L-1 for Cd (I) 228.80, Pb (I) 405.78 and Cr (I) 427.48 nm, respectively. The RMSEs of validation were 0.068 (Cd), 0.107 (Pb) and 0.112 mg·L-1 (Cr), and the recovery values were in the range of 91.2-107.9%. The agarose film-based liquid-solid conversion method achieved the desired ease of operation and sensitivity of LIBS in heavy-metal detection, thereby, showing good application prospects in heavy metal monitoring of water.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...