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1.
J Environ Sci (China) ; 146: 39-54, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38969461

RESUMEN

To improve the selective separation performance of silica nanofibers (SiO2 NFs) for cesium ions (Cs+) and overcome the defects of Prussian blue nanoparticles (PB NPs), PB/SiO2-NH2 NFs were prepared to remove Cs+ from water. Among them, 3-aminopropyltriethoxysilane (APTES) underwent an alkylation reaction with SiO2, resulting in the formation of a dense Si-O-Si network structure that decorated the surface of SiO2 NFs. Meanwhile, the amino functional groups in APTES combined with Fe3+ and then reacted with Fe2+ to form PB NPs, which anchored firmly on the aminoated SiO2 NFs surface. In our experiment, the maximum adsorption capacity of PB/SiO2-NH2 NFs was 111.38 mg/g, which was 31.5 mg/g higher than that of SiO2 NFs. At the same time, after the fifth cycle, the removal rate of Cs+ by PB/SiO2-NH2 NFs adsorbent was 75.36% ± 3.69%. In addition, the adsorption isotherms and adsorption kinetics of PB/SiO2-NH2 NFs were combined with the Freundlich model and the quasi-two-stage fitting model, respectively. Further mechanism analysis showed that the bond between PB/SiO2-NH2 NFs and Cs+ was mainly a synergistic action of ion exchange, electrostatic adsorption and membrane separation.


Asunto(s)
Cesio , Ferrocianuros , Nanofibras , Nanopartículas , Contaminantes Químicos del Agua , Purificación del Agua , Ferrocianuros/química , Nanofibras/química , Contaminantes Químicos del Agua/química , Cesio/química , Adsorción , Purificación del Agua/métodos , Nanopartículas/química , Dióxido de Silicio/química , Cinética , Propilaminas/química , Silanos
2.
Ecotoxicol Environ Saf ; 282: 116714, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38991308

RESUMEN

6:2 fluorotelomer carboxylic acid (6:2 FTCA) is a perfluorooctanoic acid (PFOA) substitute, which is supposedly less accumulative and toxic than PFOA. However, 6:2 FTCA is structurally similar to PFOA, and there had already been reports about its toxicities comparable to PFOA. The aim of the current study is to assess potential effects of developmental exposure to 6:2 FTCA on the development of kidney in chicken embryo and to investigate underlying mechanism. Fertile chicken eggs were exposed to 1.25 mg/kg, 2.5 mg/kg or 5 mg/kg doses of 6:2 FTCA, or 2 mg/kg PFOA, then incubated to hatch. Serum and kidney of hatchling chickens were collected. Blood urea nitrogen (BUN) and creatinine (Cre) levels were measured with commercially available kits. Morphology of kidney was assessed with histopathology. To further reveal molecular mechanism of observed endpoints, IGF signaling molecules were assessed in the kidney samples with qRT-PCR, results indicated that IGFBP3 is a potentially crucial molecule. Lentiviruses overexpressing or silencing IGFBP3 were designed and applied to enhance/suppress the expression of IGFBP3 in developing chicken embryo for further verification of its role in the observed effects. Disrupted nephron formation, in the manifestation of decreased glomeruli number/area and increased serum BUN/Cre levels, was observed in the animals developmentally exposed to 6:2 FTCA. Correspondingly, IGF signaling molecules (IGF1, IGF1R and IGFBP3) were affected by 6:2 FTCA exposure. Meanwhile, overexpression of IGFBP3 effectively alleviated such changes, while silencing of IGFBP3 mimicked observed effects. In conclusion, developmental exposure to 6:2 FTCA is associated with disrupted chicken embryo renal development, in which IGFBP3 seems to be a remarkable contributor, suggesting potential health risks for human and other species. Further risk assessments and mechanistic works are necessary.

3.
Heliyon ; 10(11): e31653, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38841456

RESUMEN

Obtaining high-quality adult human primary cardiomyocytes (hPCM) have been technically challenging due to isolation-induced biochemical and mechanical stress. Building upon a previous tissue slicing-assisted digestion method, we introduced polymers into the digestion solution to reduce mechanical damage to cells. We found that low-viscosity methylcellulose (MC) significantly improved hPCM viability and yield. Mechanistically, it protected cells from membrane damage, which led to decreased apoptosis and mitochondrial reactive oxygen species production. MC also improved the electrophysiological properties of hPCMs by maintaining the density of sodium channels. The effects on cell viability and cell yield effects were not recapitulated by MC of larger viscosities, other cellulose derivatives, nor shear protectants polyethylene glycol and polyvinyl alcohol. Finally, MC also enhanced the isolation efficiency and the culture quality of hPCMs from diseased ventricular myocardium, expanding its potential applications. Our findings showed that the isolation quality of hPCMs can be further improved through the addition of a polymer, rendering hPCMs a more reliable cellular model for cardiac research.

4.
Plant Sci ; 346: 112130, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38795751

RESUMEN

HD-ZIP proteins comprise a plant-specific transcription factor family, which play pivotal roles in plant development and adaptation to ever-changing environment. Although HD-ZIP family members have been identified in some plant species, so far our knowledge about HD-ZIP genes in rapeseed is still limited. In this study, 178 Brassica napus HD-ZIP (BnaHDZ) family members were identified in the rapeseed genome. The phylogenetic relationship, chromosomal locations, intron-exon structures, motif composition, and expression patterns of the BnaHDZ members were analyzed. The BnaHDZ family can be phylogenetically divided into four categories (Ⅰ, Ⅱ, Ⅲ and Ⅳ). Genome-wide transcriptome analysis revealed that most of the HD-ZIP I members respond to at least one abiotic stress. Two closely homologous stress-responsive HD-ZIP Ⅰ genes, BnaHDZ22 and BnaHDZ149, were identified to be involved in drought and salt responses, and selected for further functional characterization. Overexpressing BnaHDZ149 in rapeseed increased salt sensitivity of the transgenic plants, whereas overexpressing BnaHDZ22 increased sensitivity of the transgenic plants to polyethylene glycol (PEG)-simulated drought stress. This research provides not only a comprehensive landscape of BnaHDZ genes, but also a theoretical basis for elucidating the molecular mechanism of the abiotic stress responses of the HD-ZIP family in rapeseed.


Asunto(s)
Brassica napus , Sequías , Filogenia , Proteínas de Plantas , Brassica napus/genética , Brassica napus/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Familia de Multigenes , Regulación de la Expresión Génica de las Plantas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Plantas Modificadas Genéticamente/genética , Estrés Fisiológico/genética , Genoma de Planta , Tolerancia a la Sal/genética , Genes de Plantas
5.
Prosthet Orthot Int ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771800

RESUMEN

BACKGROUND: After amputation, people face challenges including wound healing and decreased functional mobility. Early mobilization in acute hospital care has proved safe, improved function, and sped discharge. Still, loss of a leg complicates standing and early mobilization after amputation. Approaches to early mobilization and rehabilitation after amputation surgery have not been widely studied. OBJECTIVES: To map the evidence regarding early postoperative mobilization after dysvascular amputation. Specific aims included identifying research designs and populations, describing rehabilitation approaches, and identifying gaps within the literature. STUDY DESIGN: Scoping review following PRISMA-Sc guidelines. METHODS: The a priori scoping review methodology conducted in June 2022 with English language and 20-year limits used the OVID Medline, OVID Allied and Complementary Medicine Database, Cumulative Index to Nursing and Allied Health Literature, Cochrane databases, and Journal of Prosthetics and Orthotics archive. Reviewer pairs used Covidence software to screen for inclusion (subjects with major lower limb dysvascular amputations, seen immediately postoperatively for hospital-based rehabilitation) with decisions by concurrence. Data for best practice scoping reviews were synthesized for analysis. RESULTS: Two hundred ninety-six citations were screened, 13 full texts reviewed, and 8 articles included: 2 cohort studies, 3 case-control studies, 2 single-group interventional studies, and 1 case study. There were no randomized control trials or prospective comparison group trials. CONCLUSIONS: Few studies were identified regarding acute rehabilitation after major lower extremity amputation. The limited evidence in this review suggested that early mobilization in the days after amputation was safe with or without use of temporary prostheses, although further research is certainly warranted.

6.
IEEE J Biomed Health Inform ; 28(7): 4194-4203, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38648145

RESUMEN

Soft robotic glove controlled by a brain-computer interface (BCI) have demonstrated effectiveness in hand rehabilitation for stroke patients. Current systems rely on static visual representations for patients to perform motor imagination (MI) tasks, resulting in lower BCI performance. Therefore, this study innovatively used MI and high-frequency steady-state visual evoked potential (SSVEP) to construct a friendly and natural hybrid BCI paradigm. Specifically, the stimulation interface sequentially presented decomposed action pictures of the left and right hands gripping a ball, with the pictures flashing at specific stimulation frequencies (left: 34 Hz, right: 35 Hz). Integrating soft robotic glove as feedback, we established a comprehensive "peripheral - central - peripheral" hand rehabilitation system to facilitate the hand rehabilitation of patients. Filter bank common spatial pattern (FBCSP) and filter bank canonical correlation analysis (FBCCA) algorithms were used to identify MI and SSVEP signals, respectively. Additionally, we proposed a novel fusion algorithm to decide the final output of the system. The feasibility of the proposed system was validated through online experiments involving 12 healthy subjects and 9 stroke patients, achieving accuracy rates of 95.83 ± 6.83% and 63.33 ± 10.38, respectively. The accuracy of MI and SSVEP in 12 healthy subjects reached 81.67 ± 15.63% and 95.14 ± 7.47%, both lower than the accuracy after fusion, these results confirmed the effectiveness of the proposed algorithm. The accuracy rate was more than 50% in both healthy subjects and patients, confirming the effectiveness of the proposed system.


Asunto(s)
Interfaces Cerebro-Computador , Robótica , Rehabilitación de Accidente Cerebrovascular , Humanos , Rehabilitación de Accidente Cerebrovascular/métodos , Rehabilitación de Accidente Cerebrovascular/instrumentación , Masculino , Robótica/instrumentación , Robótica/métodos , Femenino , Adulto , Persona de Mediana Edad , Electroencefalografía/métodos , Electroencefalografía/instrumentación , Potenciales Evocados Visuales/fisiología , Algoritmos , Procesamiento de Señales Asistido por Computador , Anciano , Adulto Joven , Accidente Cerebrovascular/fisiopatología , Diseño de Equipo , Mano/fisiología , Mano/fisiopatología
7.
Neural Netw ; 170: 535-547, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38043373

RESUMEN

Anomaly detection in multivariate time series is of critical importance in many real-world applications, such as system maintenance and Internet monitoring. In this article, we propose a novel unsupervised framework called SVD-AE to conduct anomaly detection in multivariate time series. The core idea is to fuse the strengths of both SVD and autoencoder to fully capture complex normal patterns in multivariate time series. An asymmetric autoencoder architecture is proposed, where two encoders are used to capture features in time and variable dimensions and a shared decoder is used to generate reconstructions based on latent representations from both dimensions. A new regularization based on singular value decomposition theory is designed to force each encoder to learn features in the corresponding axis with mathematical supports delivered. A specific loss component is further proposed to align Fourier coefficients of inputs and reconstructions. It can preserve details of original inputs, leading to enhanced feature learning capability of the model. Extensive experiments on three real world datasets demonstrate the proposed algorithm can achieve better performance on multivariate time series anomaly detection tasks under highly unbalanced scenarios compared with baseline algorithms.


Asunto(s)
Algoritmos , Internet , Factores de Tiempo , Aprendizaje
8.
ChemSusChem ; 17(4): e202301364, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-37889199

RESUMEN

Oxime chemicals are the building blocks of many anticancer drugs and widely used in industry and laboratory. A simple but robust hierarchically porous zeolite (HTS-1) catalyst was prepared by hydrothermal methods and used for the preparation of vanillin oxime from vanillin in NH3 ⋅ H2 O/DIO (v/v 1/10) system. The results of the catalyst characterization showed that the larger pore size and more framework Ti were conducive to promote the transformation of the substrates. The conversion of vanillin and the yield of vanillin oxime were both higher than 99 % under optimized reaction conditions. It was found that the reaction proceeded by oxidation of NH3 to hydroxylamine (NH2 OH), and oximation of hydroxylamine with vanillin to obtain vanillin oxime, where the rate-controlling step was the hydroxylamine formation, and the apparent activation energy was 26.22 kJ/mol. The corresponding oximation products could also be obtained by extending this method to other compounds derived from lignin. Furthermore, the catalytic system was used directly to the conversion of birch biomass to obtain oxime products such as vanillin oxime, syringaldehyde oxime, and furfural oxime etc. This work might give insights into the sustainable production of N-containing high-value products from lignocellulose.

9.
Sci China Life Sci ; 67(2): 301-319, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37864082

RESUMEN

Mitochondrial toxicity induced by therapeutic drugs is a major contributor for cardiotoxicity, posing a serious threat to pharmaceutical industries and patients' lives. However, mitochondrial toxicity testing is not incorporated into routine cardiac safety screening procedures. To accurately model native human cardiomyocytes, we comprehensively evaluated mitochondrial responses of adult human primary cardiomyocytes (hPCMs) to a nucleoside analog, remdesivir (RDV). Comparison of their response to human pluripotent stem cell-derived cardiomyocytes revealed that the latter utilized a mitophagy-based mitochondrial recovery response that was absent in hPCMs. Accordingly, action potential duration was elongated in hPCMs, reflecting clinical incidences of RDV-induced QT prolongation. In a screen for mitochondrial protectants, we identified mitochondrial ROS as a primary mediator of RDV-induced cardiotoxicity. Our study demonstrates the utility of hPCMs in the detection of clinically relevant cardiac toxicities, and offers a framework for hPCM-based high-throughput screening of cardioprotective agents.


Asunto(s)
Células Madre Pluripotentes Inducidas , Miocitos Cardíacos , Humanos , Cardiotoxicidad/etiología , Células Cultivadas , Pruebas de Toxicidad/métodos
10.
Sci Total Environ ; 912: 169365, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38104823

RESUMEN

The rapid development of nuclear energy in China has led to increased attention to the treatment of radioactive wastewaters. Herein, a novel magnetic adsorbent, magnetic Prussian blue­molybdenum disulfide (PB/Fe3O4/MoS2) nanocomposite, was prepared by a simple in-situ fixation of ferric oxide nanoparticles (Fe3O4 NPs) and Prussian Blue (PB) shell layers on the surface of molybdenum disulfide (MoS2) nanosheets carrier. The prepared PB/Fe3O4/MoS2 nanocomposites adsorbent displayed excellent fast magnetic separation and adsorption capacity of Cs+ (Qm = 80.51 mg/g) from water. The adsorption behavior of Cs+ by PB/Fe3O4/MoS2 conformed to Langmuir isothermal and second-order kinetic model, which belonged to chemical adsorption and endothermic reaction. The equilibrium adsorption capacity of PB/Fe3O4/MoS2 to Cs+ has reached 90 % in less than 110 min. Moreover, the adsorption properties of PB/Fe3O4/MoS2 remained good in the pH range of 2-7. Based on this, PB/Fe3O4/MoS2 complex was a fast and high selectivity adsorption material for Cs+, which was expected to be used in the practical treatment of cesium-containing radioactive wastewater.

11.
IEEE/ACM Trans Comput Biol Bioinform ; 20(6): 3863-3875, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37878431

RESUMEN

Few-Shot Molecular Property Prediction (FSMPP) is an improtant task on drug discovery, which aims to learn transferable knowledge from base property prediction tasks with sufficient data for predicting novel properties with few labeled molecules. Its key challenge is how to alleviate the data scarcity issue of novel properties. Pretrained Graph Neural Network (GNN) based FSMPP methods effectively address the challenge by pre-training a GNN from large-scale self-supervised tasks and then finetuning it on base property prediction tasks to perform novel property prediction. However, in this paper, we find that the GNN finetuning step is not always effective, which even degrades the performance of pretrained GNN on some novel properties. This is because these molecule-property relationships among molecules change across different properties, which results in the finetuned GNN overfits to base properties and harms the transferability performance of pretrained GNN on novel properties. To address this issue, in this paper, we propose a novel Adaptive Transfer framework of GNN for FSMPP, called ATGNN, which transfers the knowledge of pretrained and finetuned GNNs in a task-adaptive manner to adapt novel properties. Specifically, we first regard the pretrained and finetuned GNNs as model priors of target-property GNN. Then, a task-adaptive weight prediction network is designed to leverage these priors to predict target GNN weights for novel properties. Finally, we combine our ATGNN framework with existing FSMPP methods for FSMPP. Extensive experiments on four real-world datasets, i.e., Tox21, SIDER, MUV, and ToxCast, show the effectiveness of our ATGNN framework.


Asunto(s)
Descubrimiento de Drogas , Redes Neurales de la Computación
12.
Asia Pac J Clin Nutr ; 32(3): 362-373, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37789657

RESUMEN

BACKGROUND AND OBJECTIVES: We aimed to investigate the association of triglyceride-glucose (TyG) index with hypertension and compare the discriminative power of the TyG index, lipid, glycemic parameters for hypertension using the China Health Examination Collaborative study (CHEC Study). METHODS AND STUDY DESIGN: Data were collected at Ningbo Mingzhou Hospital and Beijing physical examination center from the CHEC Study during 2014 and 2021. Participants with ≥2 medical check-up times were included. The TyG index is the logarithmized product of fasting triglyceride and glucose. Generalised estimation equation (GEE) model was used to evaluate the association between the TyG index, lipid parameters, glycemic parameters and hypertension. Receiver operating characteristic (ROC) analysis was performed to explore the predictive ability of TyG index on hypertension at different years of medical check-up. RESULTS: 112,902 participants with an average age of 42.8 years were recruited in the study, 36,839 participants developed hypertension over the 8-year period. GEE model analysis showed that the ORs with 95% CI of hypertension were 3.35 (3.15-3.57), 1.86 (1.76-1.95), 1.67 (1.58-1.78), 1.45 (1.33-1.58), 1.24 (1.19-1.29), 0.92 (0.86-0.99), and 1.90 (1.83-1.97) in the highest versus lowest quintiles of TyG index, TG/HDL-C ratio, TG, TC, LDL-C, HDL-C and FPG in model 2. The area under the ROC curve of the overall years of medical check-up was signifi-cantly higher than a particular year in predicting hypertension (AUC: 0.883, p < 0.05). CONCLUSIONS: TyG index is associated with hypertension and shows the superior discriminative ability for hypertension compared with lipid and glycemic parameters.


Asunto(s)
Hipertensión , Resistencia a la Insulina , Humanos , Adulto , Triglicéridos , Glucosa , Glucemia , Pueblos del Este de Asia , China/epidemiología , Hipertensión/epidemiología , Biomarcadores
13.
Neural Netw ; 168: 256-271, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37774512

RESUMEN

As a pixel-wise dense forecast task, video prediction is challenging due to its high computation complexity, dramatic future uncertainty, and extremely complicated spatial-temporal patterns. Many deep learning methods are proposed for the task, which bring up significant improvements. However, they focus on modeling short-term spatial-temporal dynamics and fail to sufficiently exploit long-term ones. As a result, the methods tend to deliver unsatisfactory performance for a long-term forecast requirement. In this article, we propose a novel unified memory network (UNIMEMnet) for long-term video prediction, which can effectively exploit long-term motion-appearance dynamics and unify the short-term spatial-temporal dynamics and long-term ones in an architecture. In the UNIMEMnet, a dual branch multi-scale memory module is carefully designed to extract and preserve long-term spatial-temporal patterns. In addition, a short-term spatial-temporal dynamics module and an alignment and fusion module are devised to capture and coordinate short-term motion-appearance dynamics with long-term ones from our designed memory module. Extensive experiments on five video prediction datasets from both synthetic and real-world scenarios are conducted, which validate the effectiveness and superiority of our proposed method UNIMEMnet over state-of-the-art methods.


Asunto(s)
Movimiento (Física) , Incertidumbre
14.
Sci Total Environ ; 904: 166855, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37683869

RESUMEN

The use of plastics for manufacturing of products and packaging has become ubiquitous. This is because plastics are cheap, pliable, and durable. However, these characteristics of plastics have also led to their disposal in landfill, where they persist. To overcome the environmental challenge posed by conventional plastics (CPs), biodegradable plastics (BDPs) are increasingly being used. However, BDPs form residual microplastics (MPs) at a rate that far exceeds that of CPs, and MPs have negative impacts on the soil environment. This review aimed to evaluate whether the move away from CPs to BDPs is having an overall positive impact on the environment considering the formation of MPs. Topics focused on in this review include the degradation of BDPs in the soil environment and the impacts of MPs originating from BDPs on soil physical and chemical properties, microbial communities, animals, and plants. The information collated in this review can provide scientific guidance for sustainable development of the BDPs industry.


Asunto(s)
Plásticos Biodegradables , Microbiota , Contaminantes del Suelo , Animales , Microplásticos , Plásticos , Suelo , Contaminantes del Suelo/análisis
15.
Chin Herb Med ; 15(3): 407-420, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37538856

RESUMEN

Objective: Identifying novel strategies to prevent particulate matter (PM)-induced lung injury is crucial for the reduction of the morbidity of chronic respiratory diseases. The combined intervention represented by herbal formulae for simultaneously targeting multiple pathological processes can provide a more beneficial effect than the single intervention. The aim of this paper is therefore to design a safe and effective medicinal and edible Chinese herbs (MECHs) formula against PM-induced lung injury. Methods: PM-induced oxidative stress, inflammatory response and apoptosis A549 cell model were used to screen anti-oxidant, anti-inflammatory and anti-apoptotic MECHs, respectively. A network pharmacology method was utilized to rationally design a novel herbal formula. Ultra performance liquid chromatography-mass spectrometer was utilized to assess the quality control of MECHs formula. The excretion of magnetic iron oxide nanospheres of the MECHs formula was estimated in zebrafish. The MECH formula against PM-induced lung injury was investigated with mice experiments. Results: Five selected herbs were rationally designed to form a new MECH formula, including Citri Exocarpium Rubrum (Juhong), Lablab Semen Album (Baibiandou), Atractylodis Macrocephalae Rhizoma (Baizhu), Mori Folium (Sangye) and Polygonati Odorati Rhizoma (Yuzhu). The formula effectively promoted the magnetic iron oxide nanospheres excretion in zebrafish. The mid/high dose formula significantly prevented PM-induced lung damage in mice by enhancing the activity of SOD and GSH-Px, reducing the MDA and ROS level and attenuating the upregulation of pro-inflammatory cytokine (IL-6, IL-8, IL-1ß and TNF-α), down regulating the protein expression of NF-κB, STAT3 and Caspase-3. Conclusion: Our findings suggest that the effective MECHs formula will become a novel strategy for preventing PM-induced lung injury and provide a paradigm for the development of functional foods using MECHs.

16.
Int J Pharm ; 644: 123326, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37591473

RESUMEN

As one of derivatives of Vitamin B12, methylcobalamin (MeCbl) is an indispensable "Life Element" and plays an essential role in maintaining human normal physiology function and clinical medicine application. Because of the intricate molecular structure, strong hygroscopicity and optical instability, maintaining its solid stability is a great challenge in pharmaceutical preparation. Based on the structure features of MeCbl hydrates, this study explored the drug solid stability by designing solid-solid phase transformation (SSPT) experiments. Three hydrate powders of MeCbl that had special structure with isolated site and channel water molecules were discovered. It was found that drying condition and surrounding humidity were controlling factors influencing the final solid form. The inter-conversion relations relevant to heating-induced and humidity-induced structure changes were established among the three hydrate powders. Powder X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, high performance liquid chromatography and dynamic vapor sorption were used to characterize the differences and related properties of stably prepared MeCbl hydrate powders. The particle size of product could be regulated and controlled by optimizing operating conditions of crystallization process, where ultrasound-assisted and seeding-introduced were applied as promising strategies to enhance solution crystallization process. This study opens up the possibility for the stable preparation and large-scale production of polycyclic macromolecular bulk drugs like methylcobalamin.


Asunto(s)
Polvos , Humanos , Rastreo Diferencial de Calorimetría , Cromatografía Líquida de Alta Presión , Cristalización , Sustancias Macromoleculares
17.
ChemistryOpen ; 12(8): e202300111, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37551028

RESUMEN

The production of tetraethyl orthosilicate (TEOS) from biomass provides a new way for TEOS production and biomass valorization. In this study, rice straw was treated using different fractionation methods, and the content, state, and reactivity of Si in the treated samples were investigated. It was found that acid treatment and ethanol extraction kept most Si in the biomass, while alkali treatment caused significant Si loss. Si was mainly present in the SiOx , Si-O-C, and Si-O-Si states in the surface of raw rice straw, cellulose and Klason lignin. The results showed that the Si-O-Si state in rice straw was beneficial for the formation of TEOS. The removal of lipids from rice straw facilitated the production of TEOS, giving the highest TEOS yield of 76.2 %. In contrast, the production of TEOS from other samples became difficult; the simultaneous conversion of the three organic components of rice straw also facilitated the production of TEOS.

18.
Sensors (Basel) ; 23(14)2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37514566

RESUMEN

The ocean is one of the most extensive ecosystems on Earth and can absorb large amounts of carbon dioxide. Changes in seawater carbon dioxide concentrations are one of the most important factors affecting marine ecosystems. Excess carbon dioxide can lead to ocean acidification, threatening the stability of marine ecosystems and species diversity. Dissolved carbon dioxide detection in seawater has great scientific significance. Conducting online monitoring of seawater carbon dioxide can help to understand the health status of marine ecosystems and to protect marine ecosystems. Current seawater detection equipment is large and costly. This study designed a low-cost infrared carbon dioxide detection system based on molecular theory. Using the HITRAN database, the absorption spectra and coefficients of carbon dioxide molecules under different conditions were calculated and derived, and a wavelength of 2361 cm-1 was selected as the measurement channel for carbon dioxide. In addition, considering the interference effect of direct light, an infrared post-splitting method was proposed to eliminate the interference of light and improve the detection accuracy of the system. The system was designed for the online monitoring of carbon dioxide in seawater, including a peristaltic pump to accelerate gas-liquid separation, an optical path structure, and carbon dioxide concentration inversion. The experimental results showed that the standard deviation of the gas test is 3.05, the standard deviation of the seawater test is 6.04, and the error range is within 20 ppm. The system can be flexibly deployed and has good stability and portability, which can meet the needs of the online monitoring of seawater carbon dioxide concentration.

19.
Sensors (Basel) ; 23(12)2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37420630

RESUMEN

With the development of artificial intelligence technology, virtual reality technology has been widely used in the medical and entertainment fields, as well as other fields. This study is supported by the 3D modeling platform in UE4 platform technology and designs a 3D pose model based on inertial sensors through blueprint language and C++ programming. It can vividly display changes in gait, as well as changes in angles and displacements of 12 parts such as the big and small legs and arms. It can be used to combine with the module of capturing motion which is based on inertial sensors to display the 3D posture of the human body in real-time and analyze the motion data. Each part of the model contains an independent coordinate system, which can analyze the angle and displacement changes of any part of the model. All joints of the model are interrelated, the motion data can be automatically calibrated and corrected, and errors measured by an inertial sensor can be compensated, so that each joint of the model will not separate from the whole model and there will not occur actions that against the human body's structures, improving the accuracy of the data. The 3D pose model designed in this study can correct motion data in real time and display the human body's motion posture, which has great application prospects in the field of gait analysis.


Asunto(s)
Inteligencia Artificial , Análisis de la Marcha , Humanos , Marcha , Movimiento (Física) , Postura , Fenómenos Biomecánicos
20.
Water Res ; 241: 120163, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37276654

RESUMEN

Due to the high operational cost and secondary pollution of the conventional advanced nitrogen removal of municipal wastewater, a novel concept and technique of advanced synergetic nitrogen removal of partial-denitrification anammox and denitrification was proposed, which used the oxidation products of refractory organic matters in the secondary effluent of municipal wastewater treatment plant (MWWTP) by biogenic manganese oxides (BMOs) as carbon source. When the influent NH4+-N in the denitrifying filter was about 1.0, 2.0, 3.0, 4.0, 5.0 and 7.0 mg/L, total nitrogen (TN) in the effluent decreased from about 22 mg/L to 11.00, 7.85, 6.85, 5.20, 4.15 and 2.09 mg/L, and the corresponding removal rate was 49.15, 64.82, 69.40, 76.70, 81.36 and 90.58%, respectively. The proportional contribution of the partial-denitrification anammox pathway to the TN removal was 12.00, 26.45, 39.70, 46.04, 54.97 and 64.01%, and the actual CODcr consumption of removing 1 mg TN was 0.75, 1.43, 1.26, 1.17, 1.08 and 0.99 mg, respectively, which was much lower than the theoretical CODcr consumption of denitrification. Furthermore, CODcr in the effluent decreased to 8.12 mg/L with a removal rate of 72.40%, and the removed organic matters were mainly non-fluorescent organic matters. Kinds of denitrifying bacteria, anammox bacteria, hydrolytic bacteria and manganese oxidizing bacteria (MnOB) were identified in the denitrifying filter, which demonstrated that the advanced synergetic nitrogen removal was achieved. This novel technology presented the advantages of high efficiency of TN and CODcr removal, low operational cost and no secondary pollution.


Asunto(s)
Manganeso , Aguas Residuales , Desnitrificación , Nitrógeno , Carbono , Reactores Biológicos/microbiología , Oxidación-Reducción , Óxidos , Aguas del Alcantarillado
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