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1.
World J Clin Cases ; 12(18): 3589-3595, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38983431

RESUMEN

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is a new type of extracorporeal respiratory and circulatory assistance device. It can drain venous blood out of the body and inject it into veins or arteries after being oxygenated by an oxygenator (membrane lung) to replace lung and heart functions in a short time. ECMO can provide tissue blood perfusion and gas exchange almost equivalent to cardiac output and extend the effective treatment time window for patients with acute circulatory failure to restore cardiopulmonary function. CASE SUMMARY: We report a case of an 81-year-old woman who underwent whole cerebral angiography, basilar artery thrombectomy and stent thrombectomy in the posterior artery of the left brain after implantation of ECMO. The patient was admitted to the hospital due to myocardial infarction. Considering that the cause of the patient's disturbance of consciousness was unknown and cerebrovascular accident could not be ruled out after the implantation of ECMO, the department of Radioactive Intervention performed cerebral angiography. And the result of the angiography indicated vascular occlusion. After the basilar artery thrombectomy and stent thrombectomy in the posterior artery of the left brain, the patency of the occlusive vessel was achieved. CONCLUSION: Although the patient eventually died of circulatory failure, the result of this case verifies the feasibility of cerebral angiography and thrombectomy in patients with implanted ECMO in the intubated state.

2.
Heliyon ; 10(12): e32609, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38975192

RESUMEN

Closed-loop neuromodulation with intelligence methods has shown great potentials in providing novel neuro-technology for treating neurological and psychiatric diseases. Development of brain-machine interactive neuromodulation strategies could lead to breakthroughs in precision and personalized electronic medicine. The neuromodulation research tool integrating artificial intelligent computing and performing neural sensing and stimulation in real-time could accelerate the development of closed-loop neuromodulation strategies and translational research into clinical application. In this study, we developed a brain-machine interactive neuromodulation research tool (BMINT), which has capabilities of neurophysiological signals sensing, computing with mainstream machine learning algorithms and delivering electrical stimulation pulse by pulse in real-time. The BMINT research tool achieved system time delay under 3 ms, and computing capabilities in feasible computation cost, efficient deployment of machine learning algorithms and acceleration process. Intelligent computing framework embedded in the BMINT enable real-time closed-loop neuromodulation developed with mainstream AI ecosystem resources. The BMINT could provide timely contribution to accelerate the translational research of intelligent neuromodulation by integrating neural sensing, edge AI computing and stimulation with AI ecosystems.

3.
J Acad Nutr Diet ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38971221

RESUMEN

BACKGROUND: Higher coffee intake has been associated with reduced risk of prostate cancer, particularly aggressive forms. The activation of the PI3K signaling pathway plays an important role in prostate carcinogenesis. OBJECTIVE: To evaluate associations between pre-diagnostic coffee intake and a PI3K activation score, the expression/presence of PI3K regulators, and downstream effectors in tumor tissue from men with prostate cancer in the Health Professionals Follow-up Study, a prospective cohort study conducted in the US. DESIGN: A case-only study design was applied. Coffee intake was assessed using validated food frequency questionnaires completed in 1986 and every four years thereafter until prostate cancer diagnosis. PARTICIPANTS/SETTING: Study participants comprised 1,242 men diagnosed with prostate cancer from 1986 to 2009 and with tumor markers assessed from tissue microarrays constructed from tumor specimens. MAIN OUTCOME MEASURES: The outcomes include the PI3K activation score; expression of insulin receptor and IGF1 receptor; angiogenesis markers; and presence of the tumor suppressor PTEN, chronic and acute inflammation, simple atrophy, and post-atrophic hyperplasia. STATISTICAL ANALYSES PERFORMED: Multivariable linear or logistic regression was conducted to estimate associations between coffee intake and tumor marker expression/presence. RESULTS: Among coffee drinkers (86.6% of the population), median (25th-75th) coffee intake was 2 (1-3) cups/day. The associations between coffee consumption and the tumor markers of interest were generally weak with modest precision. When comparing men who drank >3 cups/day of coffee with nondrinkers, the absolute percent difference in the PI3K activation score and angiogenesis markers ranged from 0.6% to 3.6%. The odds ratios for PTEN loss, IGF1 receptor and insulin receptor expression, and presence of chronic and acute inflammation, simple atrophy, and post-atrophic hyperplasia also were not statistically significant, were imprecise, and ranged from 0.82 to 1.58. CONCLUSIONS: Coffee intake was not observed to be associated with PI3K activation, related regulators, and several effectors in prostate tumor tissue. Studies exploring alternative pathways or earlier steps in carcinogenesis are needed to investigate the underlying mechanisms of the coffee and prostate cancer association.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38910165

RESUMEN

PURPOSE: Immunohistochemical staining of programmed death-ligand 1 (PD-L1) in tumor biopsies acquired through invasive procedures is routinely employed in clinical practice to identify patients who are most likely to benefit from anti-programmed cell death protein 1 (PD-1) therapy. Nevertheless, PD-L1 expression is observed in various cellular subsets within tumors and their microenvironments, including tumor cells, dendritic cells, and macrophages. The impact of PD-L1 expression across these different cell types on the responsiveness to anti-PD-1 treatment is yet to be fully understood. METHODS: We synthesized polymer-based lysosome-targeting chimeras (LYTACs) that incorporate both PD-L1-targeting motifs and liver cell-specific asialoglycoprotein receptor (ASGPR) recognition elements. Small-animal positron emission tomography (PET) imaging of PD-L1 expression was also conducted using a PD-L1-specific radiotracer 89Zr-αPD-L1/Fab. RESULTS: The PD-L1 LYTAC platform was capable of specifically degrading PD-L1 expressed on liver cancer cells through the lysosomal degradation pathway via ASGPR without impacting the PD-L1 expression on host cells. When coupled with whole-body PD-L1 PET imaging, our studies revealed that host cell PD-L1, rather than tumor cell PD-L1, is pivotal in the antitumor response to anti-PD-1 therapy in a mouse model of liver cancer. CONCLUSION: The LYTAC strategy, enhanced by PET imaging, has the potential to surmount the limitations of knockout mouse models and to provide a versatile approach for the selective degradation of target proteins in vivo. This could significantly aid in the investigation of the roles and mechanisms of protein functions associated with specific cell subsets in living subjects.

5.
Cancer Med ; 13(12): e7388, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38924330

RESUMEN

BACKGROUND: To date, carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) have been widely used for the screening, diagnosis and prediction of biliary tract cancer (BTC) patients. However, few studies with large sample sizes of carbohydrate antigen 50 (CA50) were reported in BTC patients. METHODS: A total of 1121 patients from the Liver Cancer Clin-Bio Databank of Anhui Hepatobiliary Surgery Union between January 2017 and December 2022 were included in this study (673 in the training cohort and 448 in the validation cohort): among them, 458 with BTC, 178 with hepatocellular carcinoma (HCC), 23 with combined hepatocellular-cholangiocarcinoma, and 462 with nontumor patients. Receiver operating characteristic (ROC) curves and decision curve analysis (DCA) were used to evaluate the diagnostic efficacy and clinical usefulness. RESULTS: ROC curves obtained by combining CA50, CA19-9, and AFP showed that the AUC value of the diagnostic MODEL 1 was 0.885 (95% CI 0.856-0.885, specificity 70.3%, and sensitivity 84.0%) in the training cohort and 0.879 (0.841-0.917, 76.7%, and 84.3%) in the validation cohort. In addition, comparing iCCA and HCC (235 in the training cohort, 157 in the validation cohort), the AUC values of the diagnostic MODEL 2 were 0.893 (95% CI 0.853-0.933, specificity 96%, and sensitivity 68.6%) in the training cohort and 0.872 (95% CI 0.818-0.927, 94.2%, and 64.6%) in the validation cohort. CONCLUSION: The model combining CA50, CA19-9, and AFP not only has good diagnostic value for BTC but also has good diagnostic value for distinguishing iCCA and HCC.


Asunto(s)
Antígenos de Carbohidratos Asociados a Tumores , Neoplasias del Sistema Biliar , Biomarcadores de Tumor , Curva ROC , Humanos , Masculino , Femenino , Persona de Mediana Edad , Neoplasias del Sistema Biliar/diagnóstico , Neoplasias del Sistema Biliar/sangre , Antígenos de Carbohidratos Asociados a Tumores/sangre , Biomarcadores de Tumor/sangre , Anciano , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/sangre , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/sangre , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/sangre , Antígeno CA-19-9/sangre , Estudios Retrospectivos , Sensibilidad y Especificidad
7.
PLoS One ; 19(6): e0300036, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38843145

RESUMEN

With the continuous development of large-scale engineering projects such as construction projects, relief support, and large-scale relocation in various countries, engineering logistics has attracted much attention. This paper addresses a multimodal material route planning problem (MMRPP), which considers the transportation of engineering material from suppliers to the work zones using multiple transport modes. Due to the overall relevance and technical complexity of engineering logistics, we introduce the key processes at work zones to generate a transport solution, which is more realistic for various real-life applications. We propose a multi-objective multimodal transport route planning model that minimizes the total transport cost and the total transport time. The model by using the ε - constraint method that transforms the objective function of minimizing total transportation cost into a constraint, resulting in obtaining pareto optimal solutions. This method makes up for the lack of existing research on the combination of both engineering logistics and multimodal transportation, after which the feasibility of the model and algorithm is verified by examples. The results show that the model solution with the introduction of the key processes at work zones produces more time-efficient and less time-consuming route planning results, and that the results obtained using the ε - constraint method are more reliable than the traditional methods for solving multi-objective planning problems and are more in line with the decision maker's needs.


Asunto(s)
Algoritmos , Modelos Teóricos , Transportes , Transportes/métodos , Ingeniería/métodos , Humanos , Lugar de Trabajo
8.
Plant Physiol Biochem ; 213: 108868, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38917738

RESUMEN

The chloroplast biogenesis occurs in cotyledon during alfalfa seed germination before true leaf formation, and is extremely important for the followed plant development and growth. In this study, we conducted a simulation of alfalfa seed germination in the soil by using tin foil and focused on 10 pivotal time points of chloroplast biogenesis in cotyledons before and after light exposure, which showed significant differences in multispectral images, and covered the whole process of chloroplast biogenesis from proplastid, etioplast to mature chloroplast. We revealed three phases that referred to the programmed involvements of photosynthesis promotion, ultrastructure maturity, transcriptomic expression, and protein complex construction, and observed distinct transcriptional expressions of genes from nuclear and chloroplast genomes. In phase I at dark germination before light exposure, chloroplast-encoded genes showed up-regulated expressions together with the importation of chloroplast proteins. In phase II for the first day after light exposure, nuclear-encoded genes' expressions were initiated at 2 h after light exposure (E2h), followed by swift assembly of chloroplast thylakoid membrane protein complexes, and roaring Fv/Fm and contents of chlorophyll a, chlorophyll b and carotenoid. The initiation at E2h was pronounced by the observation of gradual accumulation of single lamella, and facilitated the formation of granum stacks (thylakoid) at E8h in phase II. In phase III from the second day after light exposure, chloroplast became gradually complete with the fully established photosynthetic capacity. Altogether, our results layed a theoretical foundation for enhancing potential photosynthetic efficiency in alfalfa and related species.


Asunto(s)
Cloroplastos , Regulación de la Expresión Génica de las Plantas , Germinación , Medicago sativa , Fotosíntesis , Cloroplastos/metabolismo , Cloroplastos/ultraestructura , Medicago sativa/genética , Medicago sativa/metabolismo , Medicago sativa/crecimiento & desarrollo , Semillas/metabolismo , Semillas/crecimiento & desarrollo , Semillas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Clorofila/metabolismo
9.
Cell Rep ; 43(6): 114338, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38850530

RESUMEN

The game between therapeutic monoclonal antibodies (mAbs) and continuously emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has favored the virus, as most therapeutic mAbs have been evaded. Addressing this challenge, we systematically explored a reproducible bispecific antibody (bsAb)-dependent synergistic effect in this study. It could effectively restore the neutralizing activity of the bsAb when any of its single mAbs is escaped by variants. This synergy is primarily attributed to the binding angle of receptor-binding domain (RBD)-5, facilitating inter-spike cross-linking and promoting cryptic epitope exposure that classical antibody cocktails cannot achieve. Furthermore, RBD-5 with RBD-2, RBD-6, and RBD-7, alongside RBD-8, also exhibit significantly enhanced effects. This study not only shifts the paradigm in understanding antibody interactions but paves the way for developing more effective therapeutic antibodies against rapidly mutating SARS-CoV-2, with Dia-19 already showing promise against emerging variants like BA.2.86, EG.5.1, and JN.1.


Asunto(s)
Anticuerpos Biespecíficos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19 , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , SARS-CoV-2/inmunología , Humanos , Anticuerpos Biespecíficos/inmunología , Anticuerpos Biespecíficos/farmacología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , COVID-19/virología , COVID-19/terapia , Glicoproteína de la Espiga del Coronavirus/inmunología , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Epítopos/inmunología , Unión Proteica , Animales
10.
Front Oncol ; 14: 1283991, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38884092

RESUMEN

Objective: To explore the Therapeutic effect of synchronous Integrated intensity modulated radiotherapy combined with chemotherapy in stage IIIc of Cervical Cancer. Methods: A total of 58 patients with stage IIIC cervical cancer (KPS ≥ 80) were analyzed in this study. They were admitted to our hospital between August 2017 and August 2022. Synchronous integrated boost intensity-modulated radiotherapy (SIB-IMRT) and sequential boost intensity-modulated radiotherapy (LCB-IMRT) were used to treat pelvic and/or para-aortic metastatic lymph nodes, with 30 cases in the SIB group and 28 cases in the LCB group. Comparison of short-term and long-term efficacy. Comparison of recurrence and metastasis rates, radiation dose to organs at risk and incidence of adverse drug reactions. Result: 30 patients were treated with simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT), and 28 patients were treated with sequential boost intensity-modulated radiotherapy (LCB-IMRT). At the completion of radiotherapy and 3 months after radiotherapy, there was no significant difference in clinical efficacy observed between the two treatment groups. The median overall survival (OS), progression-free survival (PFS), and disease-free survival (DMR) in the SIB-IMRT group were significantly higher compared to the LCB-IMRT group. The SIB-IMRT group demonstrated significantly lower rates compared to the LCB-IMRT group. Furthermore, within 3 years and 5 years, the rates of lymph node recurrence, cervical and vaginal local recurrence, and distant metastasis within the radiotherapy field were significantly lower in the SIB-IMRT group compared to the LCB-IMRT group. There were no significant differences observed between the two groups in terms of the maximum dose to the small intestine (Dmax), dose received by 2cc of the small intestine (D2cc), maximum dose to the rectum (Dmax), and dose received by 1cc of the bladder (D1cc). The incidence of bone marrow toxicity in the SIB-IMRT group was significantly lower compared to the LCB-IMRT group. Moreover, the occurrence of grade III and IV bone marrow toxicity was also significantly lower in the SIB-IMRT group compared to the LCB-IMRT group. Conclusion: The study has concluded that there is no significant differences in in terms of bladder associated adverse events and gastrointestinal toxicity in both Simultaneous Integrated Boost Intensity-Modulated Radiotherapy and Layered Conical Beam Intensity-Modulated Radiation Therapy.

11.
J Hum Hypertens ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926521

RESUMEN

Racial and sexual orientation discrimination may exacerbate the double epidemic of hypertension (HTN) and HIV that affects men of color who have sex with men (MSM). This was a cross-sectional analysis of African American, Asian American, Native Hawaiian, or Pacific Islander (NHPI) MSM living with HIV (PLWH) cohort in Honolulu and Philadelphia. Racial and sexual orientation discrimination, stress, anxiety, and depression were measured with computer-assisted self-interview questionnaires (CASI). We examined the associations between racial and sexual orientation discrimination with hypertension measured both in the office and by 24-h ambulatory blood pressure monitoring (ABPM) using multivariable logistic regression. Sixty participants (60% African American, 18% Asian, and 22% NHPI) completed CASIs and 24-h ABPM. African American participants (80%) reported a higher rate of daily racial discrimination than Asian American (36%) and NHPI participants (17%, p < 0.001). Many participants (51%) reported daily sexual orientation discrimination. Sixty-six percent of participants had HTN by office measurement and 59% had HTN by 24-h ABPM measurement. Participants who experienced racial discrimination had greater odds of having office-measured HTN than those who did not, even after adjustment (Odds Ratio 5.0 (95% Confidence Interval [1.2-20.8], p = 0.03)). This association was not seen with 24-h ABPM. Hypertension was not associated with sexual orientation discrimination. In this cohort, MSM of color PLWH experience significant amounts of discrimination and HTN. Those who experienced racial discrimination had higher in-office blood pressure. This difference was not observed in 24-h APBM and future research is necessary to examine the long-term cardiovascular effects.

12.
Int J Biol Macromol ; 273(Pt 2): 132959, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38848848

RESUMEN

Given the environmental concerns related to the non-degradability of conventional petroleum-based polymer films, the synthesis of biodegradable films utilizing natural polymers derived from biomass has emerged as a promising alternative, garnering significant attention in recent research endeavors. This research introduced an environmentally friendly and efficient method, utilizing extract liquid from the green ethanol pulping process as the solvent to completely dissolve carboxymethylcellulose into the film-forming liquid, and employing the solution pouring technique to successfully fabricate bamboo ethanol lignin/carboxymethylcellulose films (LCF). The findings revealed that the lignin content significantly influenced the LCF, endowing them with tunable mechanical properties, effective UV-blocking, and thermal insulation capabilities. With a lignin addition of 3.75 %, LCF-3.75 exhibited enhanced mechanical properties, characterized by a tensile strength of 19.4 MPa, along with superior UV-blocking efficiency, blocking 100 % of UVB and 99.81 % of UVA rays. Furthermore, relative to LCF-0, LCF-3.75 had been shown to possess enhanced hydrophobicity and thermal stability, culminating in the development of the composite films that showcased exceptional thermal insulation properties and biodegradability. The films not only harbored extensive application prospects as an anti-ultraviolet and heat-insulating glass films but also represented a potential avenue for the efficient utilization of lignin, thereby contributing to sustainable development.


Asunto(s)
Carboximetilcelulosa de Sodio , Etanol , Lignina , Resistencia a la Tracción , Rayos Ultravioleta , Lignina/química , Etanol/química , Carboximetilcelulosa de Sodio/química , Interacciones Hidrofóbicas e Hidrofílicas
13.
Sensors (Basel) ; 24(11)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38894303

RESUMEN

The most critical aspect of panorama generation is maintaining local semantic consistency. Objects may be projected from different depths in the captured image. When warping the image to a unified canvas, pixels at the semantic boundaries of the different views are significantly misaligned. We propose two lightweight strategies to address this challenge efficiently. First, the original image is segmented as superpixels rather than regular grids to preserve the structure of each cell. We propose effective cost functions to generate the warp matrix for each superpixel. The warp matrix varies progressively for smooth projection, which contributes to a more faithful reconstruction of object structures. Second, to deal with artifacts introduced by stitching, we use a seam line method tailored to superpixels. The algorithm takes into account the feature similarity of neighborhood superpixels, including color difference, structure and entropy. We also consider the semantic information to avoid semantic misalignment. The optimal solution constrained by the cost functions is obtained under a graph model. The resulting stitched images exhibit improved naturalness. Extensive testing on common panorama stitching datasets is performed on the algorithm. Experimental results show that the proposed algorithm effectively mitigates artifacts, preserves the completeness of semantics and produces panoramic images with a subjective quality that is superior to that of alternative methods.

14.
Heliyon ; 10(10): e30485, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38799744

RESUMEN

The specificity of scenarios and tasks in Unmanned Aerial Vehicles (UAV)-based maritime rescue poses challenges for detecting targets within images captured by drones in such environments. This study focuses on leveraging heuristic methods to extract data features from specific UAV maritime rescue images to optimize the generation of anchor boxes in detection models. Experiments conducted on the large-scale SeaDronesSee maritime rescue dataset, using the MMDetection object detection framework, demonstrated that the optimized anchor boxes, improved model performance by 48.9% to 62.8% compared to the framework's default configuration, with the most proficient model surpassing the official highest SeaDronesSee baseline by over 49.3%. Further analysis of the results revealed the variation in detection difficulty for different objects within the dataset and identified the reasons behind these differences. The methodology and analysis presented in this study hold promise for optimizing UAV-based maritime rescue object detection models as well as refining data analysis and enhancement.

15.
Life (Basel) ; 14(5)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38792567

RESUMEN

Niclosamide (NIC) is a potent salicylanilide molluscicide/helminthicide commonly utilized for parasite and mollusc control in aquatic environments. Due to its persistent presence in water bodies, there is growing concern regarding its impact on aquatic organisms, yet this remains inadequately elucidated. Consequently, this study aims to assess the hepatotoxic effects and detoxification capacity of black carp (Mylopharyngodon piceus) in a semi-static system, employing various parameters for analysis. NIC was applied to juvenile black carp at three different concentrations (0, 10 and 50 µg/L) for 28 days in an environmentally realistic manner. Exposure to 50 µg/L NIC resulted in an increase in hepatic lysozyme (LYZ), alkaline phosphatase (ALP), and complement 4 (C4) levels while simultaneously causing a decrease in peroxidase (POD) activity. Additionally, NIC exposure exhibited a dose-dependent effect on elevating serum levels of LYZ, ALP, complement 3 (C3), C4, and immunoglobulin T (IgT). Notably, the mRNA levels of immune-related genes tnfα, il8, and il6, as well as nramp and leap2, were upregulated in fish exposed to NIC. RNA-Seq analysis identified 219 differentially expressed genes (DEGs) in M. piceus after NIC exposure, with 94 upregulated and 125 downregulated genes. KEGG and GO analyses showed enrichment in drug metabolism pathways and activities related to oxidoreductase, lip oprotein particles, and cholesterol transport at 50 µg/L NIC. Additionally, numerous genes associated with lipid metabolism, oxidative stress, and innate immunity were upregulated in NIC-exposed M. piceus. Taken together, these findings indicate that NIC has the potential to cause hepatotoxicity and immunotoxicity in M. piceus. This research offers important insights for further understanding the impact of molluscicide/helminthicide aquatic toxicity in ecosystems.

16.
Chem Commun (Camb) ; 60(42): 5550-5553, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38700243

RESUMEN

Cu2O doped with atomically dispersed Rh (Rh:Cu2O) is synthesized with a wet chemical method. It shows higher activity and faradaic efficiency at lower overpotential for reduction of CO2 to C2+ products, especially C2H4, than pristine Cu2O. We found that introducing Rh promotes CO2 adsorption, *CO hydrogenation to *CHO and their coupling to O*CCHO intermediates, which contributes to enhanced catalytic performance.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 317: 124358, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38723462

RESUMEN

A fluorescent probe based on salicylate modified layered double hydroxide (LDH-SA) is presented, enabling the swift sequential detection of Al3+, fosetyl-Al and glyphosate in aqueous environment. The probe was synthesized using a simple co-precipitation procedure, and its properties and synthesis conditions were thoroughly characterized and optimized. A unique "off-on-off" fluorescent response was observed when the probe sequentially interacted with Al3+ and glyphosate, and the detection method based on this phenomenon was established. The limits of detection for Al3+ and glyphosate were determined as 0.03 µmol/L and 0.03 mg/L, respectively, with rapid detection periods of one minute and four minutes. The LDH-SA/Al3+ complex requires Al3+ to generate a chelation-gathered fluorescence effect, which is the mechanism by which it quenches LDH-SA. This is possible due to the inhibition of excited-state intramolecular proton transfer and photoinduced electron transfer processes within LDH-SA after incorporating Al3+. Upon interaction with glyphosate, competitive complexation between glyphosate and Al3+ is initiated, which leads to a recovery of the fluorescence spectrum of LDH-SA and demonstrating the "off-on-off" behavior. An "INHIBIT" logic gate system was devised utilizing the response, indicating potential applications in fluorescence-based devices. Such a rapid, sequential detection capacity is impressive. It attests to the utility of LDH-SA as a probe for Al3+ or glyphosate, and suggests promise for applications in pollutant analysis or environmental monitoring applications.

19.
BMC Chem ; 18(1): 91, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724989

RESUMEN

To improve the thermal and combustion properties of nanothermites, a design theory of changing the state of matter and structural state of the reactants during reaction was proposed. The Al/MoO3/KClO4 (Kp) nanothermite was prepared and the Al/MoO3 nanothermite was used as a control. SEM and XRD were used to characterize the nanothermites; DSC was used to test thermal properties; and constant volume and open combustion tests were performed to examine their combustion performance. Phase and morphology characterization of the combustion products were performed to reveal the mechanism of the aluminothermic reaction. The results show that the Al/MoO3/Kp nanothermite exhibited excellent thermal properties, with a total heat release of 1976 J·g- 1, increasing by approximately 33% of 1486 J·g- 1 of the Al/MoO3 nanothermite, and activation energy of 269.66 kJ·mol- 1, which demonstrated higher stability than the Al/MoO3 nanothermite (205.64 kJ·mol- 1). During the combustion test, the peak pressure of the Al/MoO3/Kp nanothermite was 0.751 MPa, and the average pressure rise rate was 25.03 MPa·s- 1, much higher than 0.188 MPa and 6.27 MPa·s- 1 of the Al/MoO3 nanothermite. The combustion products of Al/MoO3 nanothermite were Al2O3, MoO, and Mo, indicating insufficient combustion and incomplete reaction, whereas, the combustion products of Al/MoO3/Kp nanothermite were Al2O3, MoO, and KCl, indicating complete reaction. Their "coral-like" morphology was the effect of reactants solidifying after melting during the combustion process. The characterization of reactants and pressure test during combustion reveals the three stages of aluminothermic reaction in thermites. The excellent thermal and combustion performance of Al/MoO3/Kp nanothermite is attributed to the melt and decomposition of Kp into O2 in the third stage. This study provides new ideas and guidance for the design of high-performance nanothermites.

20.
Sensors (Basel) ; 24(10)2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38794109

RESUMEN

Taking the AquaCrop crop model as the research object, considering the complexity and uncertainty of the crop growth process, the crop model can only achieve more accurate simulation on a single point scale. In order to improve the application scale of the crop model, this study inverted the canopy coverage of a tea garden based on UAV multispectral technology, adopted the particle swarm optimization algorithm to assimilate the canopy coverage and crop model, constructed the AquaCrop-PSO assimilation model, and compared the canopy coverage and yield simulation results with the localized model simulation results. It is found that there is a significant regression relationship between all vegetation indices and canopy coverage. Among the single vegetation index regression models, the logarithmic model constructed by OSAVI has the highest inversion accuracy, with an R2 of 0.855 and RMSE of 5.75. The tea yield was simulated by the AquaCrop-PSO model and the measured values of R2 and RMSE were 0.927 and 0.12, respectively. The canopy coverage R2 of each simulated growth period basically exceeded 0.9, and the accuracy of the simulation results was improved by about 19.8% compared with that of the localized model. The results show that the accuracy of crop model simulation can be improved effectively by retrieving crop parameters and assimilating crop models through UAV remote sensing.

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