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1.
Technol Cancer Res Treat ; 23: 15330338241234791, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38592291

RESUMEN

INTRODUCTION: The incidence of breast cancer has steadily risen over the years owing to changes in lifestyle and environment. Presently, breast cancer is one of the primary causes of cancer-related deaths among women, making it a crucial global public health concern. Thus, the creation of an automated diagnostic system for breast cancer bears great importance in the medical community. OBJECTIVES: This study analyses the Wisconsin breast cancer dataset and develops a machine learning algorithm for accurately classifying breast cancer as benign or malignant. METHODS: Our research is a retrospective study, and the main purpose is to develop a high-precision classification algorithm for benign and malignant breast cancer. To achieve this, we first preprocessed the dataset using standard techniques such as feature scaling and handling missing values. We assessed the normality of the data distribution initially, after which we opted for Spearman correlation analysis to examine the relationship between the feature subset data and the labeled data, considering the normality test results. We subsequently employed the Wilcoxon rank sum test to investigate the dissimilarities in distribution among various breast cancer feature data. We constructed the feature subset based on statistical results and trained 7 machine learning algorithms, specifically the decision tree, stochastic gradient descent algorithm, random forest algorithm, support vector machine algorithm, logistics algorithm, and AdaBoost algorithm. RESULTS: The results of the evaluation indicated that the AdaBoost-Logistic algorithm achieved an accuracy of 99.12%, outperforming the other 6 algorithms and previous techniques. CONCLUSION: The constructed AdaBoost-Logistic algorithm exhibits significant precision with the Wisconsin breast cancer dataset, achieving commendable classification performance for both benign and malignant breast cancer cases.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Estudios Retrospectivos , Algoritmos , Aprendizaje Automático , Máquina de Vectores de Soporte
2.
BMC Psychiatry ; 23(1): 861, 2023 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-37990205

RESUMEN

BACKGROUND: Medical university students are confronted with unprecedented uncertainty and stress compared with their peers. Research has explored the effect of intolerance of uncertainty on perceived stress, but little attention was paid to investigate the mediating mechanisms behind this relationship, especially among medical university students. The aim of this study was to examine whether psychological resilience and neuroticism played a mediating role between medical university students' intolerance of uncertainty and perceived stress. METHODS: A total of 717 medical university students from Chongqing in Southwest China were recruited to participate in our study and completed demographic information, Intolerance of Uncertainty Scale Short Version (IUS-12), Chinese Version of Perceived Stress Scale (CPSS), Connor-Davidson Resilience Scale-10 (CD-RISC-10) and Eysenck Personality Questionnaire (EPQ). RESULTS: (1) Significant correlations between intolerance of uncertainty, perceived stress, psychological resilience and neuroticism were found. (2) Intolerance of uncertainty affected medical university students' perceived stress via three paths: the mediating effect of psychological resilience, the mediating effect of neuroticism, and the chain mediating effect of both psychological resilience and neuroticism. CONCLUSIONS: Intolerance of uncertainty could directly affect the perceived stress of medical university students, and also affected perceived stress through the mediating roles of psychological resilience and neuroticism, as well as through the chain mediating role of these two variables.


Asunto(s)
Resiliencia Psicológica , Estudiantes de Medicina , Humanos , Neuroticismo , Universidades , Incertidumbre , Estudiantes de Medicina/psicología , China , Estrés Psicológico/psicología
4.
Int J Biol Macromol ; 241: 124458, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37076067

RESUMEN

It is a promising idea to graft zwitterionic polymers onto lignin and prepare lignin-grafted-poly [2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide (Lignin-g-PDMAPS) thermosensitive polymer with the upper critical solution temperature (UCST). In this paper, an electrochemically mediated atom transfer radical polymerization (eATRP) method was used to prepare Lignin-g-PDMAPS. The structure and property of the Lignin-g-PDMAPS polymer were characterized by the fourier transform infrared spectrum (FT-IR), nuclear magnetic resonance (NMR), X-ray electron spectroscopy (XPS), dynamic light scattering (DLS), differential scanning calorimeter (DSC). Furthermore, the effect of catalyst structure, applied potential, amount of Lignin-Br, Lignin-g-PDMAPS concentration, NaCl concentration on UCST of Lignin-g-PDMAPS were investigated. It was worth noting that polymerization was well controlled when the ligand was tris (2-aminoethyl) amine (Me6TREN), applied potential was -0.38 V and the amount of Lignin-Br was 100 mg. And the UCST of the Lignin-g-PDMAPS aqueous solution (1 mg/ml) was 51.47 °C, the molecular weight was 8987 g/mol, and the particle size was 318 nm. It was also found that the UCST increased and the particle size decreased with the Lignin-g-PDMAPS polymer concentration increased, and the UCST decreased and the particle size increased with the NaCl concentration increases. This work investigated UCST-thermoresponsive polymer which possessed lignin main chain combining the zwitterionic side chain, and provided a new way for development of lignin based UCST-thermoresponsive materials and medical carrier materials, in addition to expand the scope of eATRP.


Asunto(s)
Lignina , Polímeros , Polímeros/química , Lignina/química , Temperatura , Espectroscopía Infrarroja por Transformada de Fourier , Cloruro de Sodio , Polimerizacion
5.
ACS Omega ; 8(6): 5486-5496, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36816634

RESUMEN

Temperature plays an important role in anaerobic digestion (AD), and different substrates have different optimum temperatures in AD. However, the effect of temperature on the performance of AD when cellulosic ethanol wastewater was used as a substrate was rarely reported. Therefore, the digestion characteristics of cellulosic ethanol wastewater at 25, 35, 45, and 55 °C were investigated, and the microbial communities of the sludge sample were analyzed after fermentation. The results showed that the cumulative methane production was the highest at 55 °C, 906.40 ± 50.67 mL/g VS, which was 81.06, 72.42, and 13.33% higher than that at 25, 35, and 45 °C, respectively. The content of methane was 68.13, 49.26, 70.46, and 85.84% at the terminal period of fermentation at temperatures of 25, 35, 45, and 55 °C, respectively. The testing of volatile fatty acids (VFAs) indicated that the accumulation of VFAs did not occur when the fermentation was carried out at 25, 35, and 45 °C; however, the VFA content at 55 °C was much larger than that in the three groups (25, 35, and 45 °C), and the ratio of propionic acid to acetic acid was larger than 1.4 at the late stage of fermentation, so it inhibited the fermentation. The diversity of the microbial community indicated that the floral structure and metabolic pathway of fermentation were alike at 25 and 35 °C. Firmicutes and Proteobacteria were the main flora covering the 25-55 °C-based phylum or below it. The relative abundance of Methanosaeta was the highest when fermentation temperatures were 25 and 35 °C; however, its relative abundance decreased sharply and the relative abundance of Methanosarcina increased substantially when the temperature increased from 35 to 45 °C, which indicated that Methanosarcina can exist in higher temperatures. At the same time, hydrogenotrophic methanogens such as Methanoculleus and Methanothermobacter were dominant when fermentation temperatures were 45 and 55 °C, which indicated that the metabolic pathway changed from acetoclastic methanogenesis to hydrogenotrophic methanogenesis.

6.
Front Public Health ; 10: 988577, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36225782

RESUMEN

Increasing research has shown that mindfulness-based interventions can effectively alleviate anxiety; however, the underlying neural mechanism has not yet been elucidated. Recent studies suggest that abnormal and excessive anticipatory responses to unpredictable threats play an important role in anxiety symptoms. Mindfulness refers to the non-judgmental awareness of the present moment's real experience, which is antithetical to the future-oriented thinking processes involved in anxiety-oriented cognition and its corresponding emotion regulation tactics. Thus, mitigating anticipatory threat responses may be a potential mechanism by which mindfulness alleviates anxiety. This study aimed to detect the possible mediating effects of anticipatory threat responses on the relationship between mindfulness and anxiety. A total of 35 trait-anxious (TA) individuals and 36 low-anxious (LA) individuals were recruited to participate in the predictable and unpredictable threat test. Self-reported intolerance of uncertainty (IU) and electroencephalographic responses to uncertainty were recorded. TA individuals reported more IU and less mindfulness, and exhibited significantly higher late positive potential (LPP) and longer reaction time (RT) than LA individuals in the unpredictable negative threat condition. In addition, there were significant mediating effects of the LPP amplitude and RT in the uncertain threats on the relationship between mindfulness and anxiety. The data from this study verified that mitigating anticipatory threat responses (including self-reported IU, behavioral RT, and LPP amplitude) might be the potential mechanism by which mindfulness alleviates anxiety. These findings may have practical implications for the development and optimization of mindfulness treatments for anxiety.


Asunto(s)
Atención Plena , Ansiedad/psicología , Trastornos de Ansiedad , Estudios Transversales , Humanos , Incertidumbre
7.
Biomater Sci ; 10(15): 4284-4292, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35766813

RESUMEN

This work was carried out in order to broaden the application field of lignin and improve its additional value. The degraded deep eutectic solvent lignin-grafted poly(N-vinyl caprolactam) (DES-lignin-g-PNVCL) was synthesized by using modified DES-lignin and NVCL via activators regenerated by electron transfer-atom transfer radical polymerization (ARGET-ATRP). Aspirin was coated with DES-lignin-g-PNVCL through self-assembly by an ethanol/water anti-solvent method to obtain lignin thermosensitive polymer nanoparticle coated aspirin (aspirin@LTNP). X-ray electron spectroscopy (XPS), elemental analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), and ultraviolet visible spectroscopy (UV) were used to characterize the composition, structure and morphology of DES-lignin-g-PNVCL and aspirin@LTNP. The releasing behavior of aspirin@LTNP at different temperatures and pH values was investigated. The safety was evaluated by cytotoxicity tests. The results indicated that aspirin@LTNP was mainly accumulated by the hydrophobic effect and π-π interaction in the process of self-assembly, and its morphology was an ellipsoid stacked layer by layer. The aspirin@LTNP hydrophilic chains were increased and had externally hydrophilic and internally hydrophobic structures. The particle size decreased slightly during the self-assembly process. The red-shift occurred at the π-π interaction wavelength of the lignin aromatic ring, which indicated a physical coating process. The coating rate of aspirin@LTNP was 88.87%. Aspirin@LTNP showed an obvious temperature response; the 96 h cumulative release rate at the LCST was 73.75 ± 1.16%, while the 96 h cumulative release rate above the LCST was 28.10 ± 0.92%. The 96 h cumulative release rate was 63.21 ± 0.57% at pH = 1.5 and 49.56 ± 0.48% at pH = 7.4. The dosage of aspirin@LTNP used in the experiment was safe. This study provided a strategy for drug coating and controlled release.


Asunto(s)
Lignina , Nanopartículas , Aspirina , Polímeros/química , Espectroscopía Infrarroja por Transformada de Fourier
8.
Int J Biol Macromol ; 194: 358-365, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34800520

RESUMEN

To expand the field of high-value utilization of lignin. The degraded deep eutectic solvent lignin-grafted poly (N-Vinyl caprolactam) (DES-lignin-g-PNVCL) was synthesized by modified DES-lignin and NVCL via the combination of activators regenerated by electron transfer-atom transfer radical polymerization (ARGET-ATRP). Fourier transform infrared spectroscopy (FT-IR), 1H NMR, X-ray electron spectroscopy (XPS), dynamic light scattering (DLS), differential scanning calorimeter (DSC) were used to characterize the structure and performance of DES-lignin-g-PNVCL. The results indicated that the PNVCL and DES-lignin-g-PNVCL were successfully prepared by ARGET-ATRP. The lowest critical solution temperature (LCST) of PNVCL was 35.75 °C. Due to different strength of hydrogen bond, different energies were required, so the LCST of the polymer can be regulated. When the molar ratio of phenolic hydroxyl group in degraded DES-lignin to 2-bromoisobutyryl bromide (BiBB) was increased from 1:1 to 1:7, the grafting rate of DES-lignin-Br was increased from 32.87% to 60.84%, and the LCST of DES-lignin-g-PNVCL was decreased from 47.98 °C to 27.88 °C. The LCST of DES-lignin-g-PNVCL was increased from 30.98 °C to 44.64 °C when the addition amount of DES-lignin-Br was increased from 20 mg to 200 mg. The LCST of DES-lignin-g-PNVCL was increased from 27.20 °C to 39.86 °C when the ratio of DMF/water was increased from 1:4 to 4:1. The LCST of DES-lignin-g-PNVCL was decreased from 52.10 °C to 31.02 °C when the concentration of DES-lignin-g-PNVCL was increased from 0.5 mg/mL to 2.5 mg/mL. The equation represented the relationship between LCST and influencing factors was obtained, the good predictability provided a tactics for preparing desired LCST thermo-responsible polymer.


Asunto(s)
Caprolactama/análogos & derivados , Disolventes Eutécticos Profundos/química , Lignina/química , Polímeros/química , Rastreo Diferencial de Calorimetría , Caprolactama/síntesis química , Caprolactama/química , Fenómenos Químicos , Técnicas de Química Sintética , Dispersión Dinámica de Luz , Estructura Molecular , Polimerizacion , Polímeros/síntesis química , Espectroscopía Infrarroja por Transformada de Fourier
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