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1.
BMC Med Inform Decis Mak ; 24(1): 18, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38243204

RESUMEN

OBJECTIVE: To develop a Chinese Diabetes Mellitus Ontology (CDMO) and explore methods for constructing high-quality Chinese biomedical ontologies. MATERIALS AND METHODS: We used various data sources, including Chinese clinical practice guidelines, expert consensus, literature, and hospital information system database schema, to build the CDMO. We combined top-down and bottom-up strategies and integrated text mining and cross-lingual ontology mapping. The ontology was validated by clinical experts and ontology development tools, and its application was validated through clinical decision support and Chinese natural language medical question answering. RESULTS: The current CDMO consists of 3,752 classes, 182 fine-grained object properties with hierarchical relationships, 108 annotation properties, and over 12,000 mappings to other well-known medical ontologies in English. Based on the CDMO and clinical practice guidelines, we developed 200 rules for diabetes diagnosis, treatment, diet, and medication recommendations using the Semantic Web Rule Language. By injecting ontology knowledge, CDMO enhances the performance of the T5 model on a real-world Chinese medical question answering dataset related to diabetes. CONCLUSION: CDMO has fine-grained semantic relationships and extensive annotation information, providing a foundation for medical artificial intelligence applications in Chinese contexts, including the construction of medical knowledge graphs, clinical decision support systems, and automated medical question answering. Furthermore, the development process incorporated natural language processing and cross-lingual ontology mapping to improve the quality of the ontology and improved development efficiency. This workflow offers a methodological reference for the efficient development of other high-quality Chinese as well as non-English medical ontologies.


Asunto(s)
Ontologías Biológicas , Diabetes Mellitus , Humanos , Inteligencia Artificial , Lenguaje , Semántica , Diabetes Mellitus/diagnóstico
2.
Sensors (Basel) ; 23(16)2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37631783

RESUMEN

Tree height is a crucial structural parameter in forest inventory as it provides a basis for evaluating stock volume and growth status. In recent years, close-range photogrammetry based on smartphone has attracted attention from researchers due to its low cost and non-destructive characteristics. However, such methods have specific requirements for camera angle and distance during shooting, and pre-shooting operations such as camera calibration and placement of calibration boards are necessary, which could be inconvenient to operate in complex natural environments. We propose a tree height measurement method based on three-dimensional (3D) reconstruction. Firstly, an absolute depth map was obtained by combining ARCore and MidasNet. Secondly, Attention-UNet was improved by adding depth maps as network input to obtain tree mask. Thirdly, the color image and depth map were fused to obtain the 3D point cloud of the scene. Then, the tree point cloud was extracted using the tree mask. Finally, the tree height was measured by extracting the axis-aligned bounding box of the tree point cloud. We built the method into an Android app, demonstrating its efficiency and automation. Our approach achieves an average relative error of 3.20% within a shooting distance range of 2-17 m, meeting the accuracy requirements of forest survey.

3.
Entropy (Basel) ; 25(5)2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37238508

RESUMEN

Adding time delay to nonlinear systems can significantly improve their performance, making it possible to construct image-encryption algorithms with higher security. In this paper, we propose a time-delayed nonlinear combinatorial hyperchaotic map (TD-NCHM) with a wide hyperchaotic interval. Based on TD-NCHM, we develop a fast and secure image-encryption algorithm that includes a plaintext-sensitive key-generation method and a simultaneous row-column shuffling-diffusion encryption process. Plenty of experiments and simulations demonstrate the superiority of the algorithm in terms of efficiency, security, and practical value in secure communications.

4.
Phys Chem Chem Phys ; 23(4): 2906-2913, 2021 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-33475637

RESUMEN

The success of fascinating graphene has motivated much interest in exploiting new two-dimensional (2D) carbon allotropes with excellent electronic and mechanical properties such as graphdiyne and penta-graphene. However, there are only very few reported structures for stable 2D all-sp3 carbon allotropes. Here, we proposed a new 2D all-sp3 carbon allotrope, named as TTH-carbon. Using first-principles calculations, we investigated its structure, stability, elastic constants, band structure, carrier mobility and optical properties. The results show that it exhibits good stability. Meanwhile, it possesses a total monolayer thickness of 1.35 Šand an indirect band gap of 3.23 eV, comparable to those of well-known penta-graphene (1.20 Šand 3.25 eV). The calculated mechanical and optical properties of TTH-carbon strongly depend on the crystal orientation. The mobilities of electrons and holes along the y direction are ∼3000 cm2 V-1 s-1, which are ten times of its carrier mobilities along the x direction and three times of that of black phosphorus (∼1000 cm2 V-1 s-1). The proposed structure richens the 2D all-sp3 carbon allotropes and its properties make it a promising material for nanoelectronic and photoelectronic devices.

5.
Eur J Appl Physiol ; 121(10): 2773-2785, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34148146

RESUMEN

PURPOSE: To compare the effects of 12-week high-intensity interval training (HIIT) and vigorous-intensity continuous training (VICT) on cognitive function, physical fitness, VO2max, serum neurotransmitters and neurotrophic factors in overweight and obese elderly individuals. METHODS: Twenty-nine physically inactive older adults (18 males and 11 females) with a mean age of 64.8 ± 3.9 years were randomly divided into a control group (CON, n = 9), an HIIT group (4 × 3 min at 90% VO2max interspersed with 3 min at 60% VO2max, n = 10) and a VICT group (25 min at 70% VO2max, n = 10) and submitted to 12 weeks of training. Cognitive function questionnaires, physical fitness, VO2max, serum neurotransmitters and neurotrophic factors were determined at baseline and post training. RESULTS: Twelve weeks of HIIT and VICT improved the VO2max (4.19 ± 2.21 and 1.84 ± 1.63 mL/kg/min, respectively, p = 0.005), sit-and-reach distance (8.7 ± 3.0 and 7.8 ± 3.8 cm, p = 0.033), choice reaction time (- 0.115 ± 0.15 and - 0.09 ± 0.15 s, p = 0.004) and one-leg stand time (4.4 ± 3.4 and 4.2 ± 4.0 s, p < 0.001) of the elderly participants. The serum concentrations of brain-derived neurotrophic factor (375.5 ± 247.9 and 227.0 ± 137.1 pg/ml, p = 0.006), nerve growth factor (33.9 ± 16.7 and 23.3 ± 14.5 pg/ml, p = 0.037), neurotrophin-3 (24.2 ± 9.33 and 16.3 ± 5.91 pg/ml, p = 0.006) and neurotrophin-4 (10.4 ± 3.8 and 7.8 ± 5.0 pg/ml, p = 0.029) increased significantly in the HIIT and VICT groups after training. In addition, compared to VICT, HIIT significantly increased VO2max and the serum neurotrophin-3 concentration. Serum concentrations of the neurotransmitters acetylcholine, dopamine and serotonin trended upward with training. No significant change was observed in the cognitive function questionnaire scores (p > 0.05). CONCLUSION: HIIT is suitable for elderly adults and is more effective than VICT for improving VO2max and serum neurotrophin-3 concentrations. CHINESE CLINICAL TRIAL REGISTRY NUMBER: No. ChiCTR1900022315, date of registration: 4 April 2019.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad , Factores de Crecimiento Nervioso/sangre , Obesidad/fisiopatología , Sobrepeso/fisiopatología , Anciano , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Aptitud Física/fisiología
6.
Langmuir ; 35(23): 7578-7587, 2019 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-30272980

RESUMEN

Atomic force microscopy (AFM) indentation is a popular method for characterizing the micromechanical properties of soft materials such as living cells. However, the mechanical data obtained from deep indentation measurements can be difficult and problematic to interpret as a result of the complex geometry of a cell, the nonlinearity of indentation contact, and constitutive relations of heterogeneous hyperelastic soft components. Living MDA-MB-231 cells were indented by spherical probes to obtain morphological and mechanical data that were adopted to build an accurate finite element model (FEM) for a parametric study. Initially, a 2D-axisymmetric numerical model was constructed with the main purpose of understanding the effect of geometrical and mechanical properties of constitutive parts such as the cell body, nucleus, and lamellipodium. A series of FEM deformation fields were directly compared with atomic force spectroscopy in order to resolve the mechanical convolution of heterogeneous parts and quantify Young's modulus and the geometry of nuclei. Furthermore, a 3D finite element model was constructed to investigate indentation events located far from the axisymmetric geometry. In this framework, the joint FEM/AFM approach has provided a useful methodology and a comprehensive characterization of the heterogeneous structure of living cells, emphasizing the deconvolution of geometrical structure and the true elastic modulus of the cell nucleus.


Asunto(s)
Análisis de Elementos Finitos , Fenómenos Mecánicos , Microscopía de Fuerza Atómica , Fenómenos Biomecánicos , Línea Celular Tumoral , Humanos , Modelos Biológicos
7.
J Phys Chem A ; 123(18): 4034-4047, 2019 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-30986060

RESUMEN

Molecular engineering is significantly important for developing electron donor and acceptor materials of active layers in organic photovoltaics (OPVs). The OPVs based on halogenated donors frequently produced high power conversion efficiencies. Here, based upon density functional theory calculations with optimally tuned range separation parameters and solid polarization effects, we studied the effects of donor halogenation on molecular geometries, electronic structures, excitation, and spectroscopic properties for F nZnPc ( n = 0, 4, 8, 16) and Cl nSubPc ( n = 0, 6) monomers and the complexes with C60 as well as the photoinduced direct charge transfer (CT), exciton dissociation (ED), and charge recombination (CR) processes that were described by rate constants calculated using Marcus theory. The tiny differences of the molecular orbital energy gap, excitation, and spectroscopic properties of F nZnPc ( n = 0, 4, 8, 16) and Cl nSubPc ( n = 0, 6) monomers suggest that halogenation cannot effectively tune the electronic and optical gap but the significant decrease of molecular orbital energies support the idea that halogenation has a remarkable influence on the energy level alignment at heterojunction interfaces. The halogenation also enhances intermolecular binding energies between C60 and donors and increases the CT excitation energies of donor/C60 complexes, which are favorable for improving open circuit voltage. Furthermore, for F nZnPc/C60 ( n = 0, 4, 8, 16) and SubPc/C60 ( n = 0, 6) complexes, the CR rates dramatically decrease (several orders) with increasing number of halogen atoms (except for F16ZnPc/C60), meaning suppression of CR processes by halogenation. As for the special case of F16ZnPc/C60, it underlines the importance of fluorination degree in molecular design of donor materials. This study provides a theoretical understanding of the halogenation effects of donors in OPVs and may be helpful in molecular design for electron donor materials.

8.
Cell Physiol Biochem ; 45(2): 558-571, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29402837

RESUMEN

BACKGROUND/AIMS: Diabetes mellitus (DM) has become an increasingly epidemic metabolic disease. Vascular endothelial cells play a key role in developing the cardiovascular complications of DM. The A2B receptor is expressed in vascular endothelial cells, and may help regulate the function of endothelial cells. The aim of this study was to investigate the protective effects of oxymatrine (OMT) on human umbilical vein endothelial cells (HUVECs) from high glucose-induced cytotoxicity. METHODS: Homology modeling and molecular docking analysis were used to detect the binding sites between the adenosine A2B receptor and OMT. HUVECs were cultured with control (5.5 mM) or elevated glucose (22.2 mM) in the presence or absence of 3 µM OMT or A2B siRNA for 3 days. The MTS cell viability assay was used to measure the toxicity of high glucose on HUVECs and the protective effect of OMT or A2B siRNA. The expression of the adenosine A2B receptor and CCL5 in HUVECs was detected with real-time quantitative PCR (qPCR) and Western blotting methods in each group. Levels of IL-1ß and TNF-α were measured using an enzyme-linked immunosorbent assay (ELISA) kit, and the concentration of NO was detected with the nitrate reductase method. Monocyte chemotactic activity in each group was detected using Transwell chambers. Furthermore, the phosphorylation of p38 and ERK1/2 in each group was observed through the Western blotting method. RESULTS: Homology modeling and molecular docking analysis showed that OMT contains well-fitted binding sites to the A2B receptor. After chronic culture at high glucose, the rate of cell viability was significantly lower than that of the control group. After co-treatment with OMT or A2B siRNA, cell viability was significantly increased compared with the high-glucose group. The results from real-time quantitative RT-PCR (qRT-PCR) and Western blotting indicated that high glucose could increase the expression of A2B receptors in HUVECs, an effect that was inhibited by OMT. In addition, the results revealed that the expression of CCL5, IL-1ß and TNF-α was increased in the high-glucose group, and that the NO produced by HUVECs decreased due to hyperglycemia; however, co-culture with OMT or A2B siRNA abolished these effects. Meanwhile, the chemotaxis activity of monocytes to HUVECs cultured in high-glucose medium was enhanced 2.59-fold compared to the control cells. However, the inflammatory reactions in HUVECs were completely relieved by co-treatment with OMT or A2B siRNA. Moreover, the phosphorylation of p38 and ERK1/2 in HUVECs in the high-glucose group was significantly higher than that of the control group; these effects were reversed after co-treatment with OMT or A2B siRNA. CONCLUSION: OMT may protect the HUVECs from high glucose-induced cytotoxicity through inhibitting the expression of A2B receptor and inflammatory factors as well as decreasing the phosphorylation of p38 and ERK1/2.


Asunto(s)
Alcaloides/farmacología , Expresión Génica/efectos de los fármacos , Glucosa/toxicidad , Sustancias Protectoras/farmacología , Quinolizinas/farmacología , Receptor de Adenosina A2B/metabolismo , Alcaloides/química , Alcaloides/metabolismo , Supervivencia Celular/efectos de los fármacos , Quimiocina CCL5/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Interleucina-1beta/análisis , Interleucina-1beta/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Simulación del Acoplamiento Molecular , Monocitos/citología , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Fosforilación/efectos de los fármacos , Sustancias Protectoras/química , Sustancias Protectoras/metabolismo , Estructura Terciaria de Proteína , Quinolizinas/química , Quinolizinas/metabolismo , Interferencia de ARN , Receptor de Adenosina A2B/química , Receptor de Adenosina A2B/genética , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/análisis , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
9.
J Phys Chem A ; 121(13): 2655-2664, 2017 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-28319383

RESUMEN

Novel dye sensitizers are highly expected in the development of dye-sensitized solar cells (DSSCs) because dye sensitizers can significantly affect the power conversion efficiency (PCE). Here, the molecular docking strategy is applied to design panchromatic dye sensitizers for DSSCs to improve light-harvesting efficiency covering the full solar spectrum. Considering the broad absorption bands of tetraanthracenylporphyrins (TAnPs) and tetraazuleneporphyrins (TAzPs), based upon porphyrin dye sensitizer YD2-o-C8, the panchromatic dye sensitizers coded as H2(TAnP)-α, H2(TAzP)-γ, H2(TAzP)-ε, and H2(TAzP)-δ are designed by the substitution of the porphyrin-ring in YD2-o-C8 with TAnPs and TAzPs moieties at different positions. The geometries, electronic structures, and excitation properties of the designed dye sensitizers are investigated using density functional theory (DFT) and time-dependent DFT methods. The analysis of geometries, conjugation lengths, electronic structures, absorption spectra, transition configurations, exciton binding energies, and free energy variations for electron injection and dye regeneration supports that the designed molecules are effective to be applied as potential candidates of dye sensitizers for DSSCs. Among the designed dye sensitizers, H2(TAzP)-γ and H2(TAnP)-α must have the better performance in DSSCs.

10.
Sheng Li Xue Bao ; 69(1): 89-95, 2017 Feb 25.
Artículo en Zh | MEDLINE | ID: mdl-28217812

RESUMEN

Trigeminal neuralgia (TN) is a kind of recurrent transient and severe pain that is limited to the trigeminal nerve in one or more branches. The clinical incidence of TN is high, which seriously affects the quality of life of the patients and is difficult to cure. The present study investigated the effects of tetramethylpyrazine (TMP) on TN induced by chronic constriction injury of the infraorbital nerve (ION-CCI) in rats. Adult male Sprague-Dawley rats were randomly assigned to four groups: sham, sham treated with TMP (Sham+TMP), TN model (TN), and TN treated with TMP (TN+TMP). The rat TN model was established by ION-CCI and TMP (50 mg/kg) was injected intraperitoneally once a day for 2 weeks after operation. The mechanical response threshold was tested by the electronic von Frey filaments. The expression of CGRP in the trigeminal ganglia (TGs) of rats on the operative side was detected by RT-PCR, immunohistochemical staining and Western blot. In 15 days after operation, TN group showed a robust decrease in mechanical response threshold as compared with sham group. From day 9 to day 15 after operation, TMP treatment significantly suppressed the TN-induced mechanical hyperalgesia (P < 0.05). On day 15 after operation, RT-PCR, immunohistochemical staining and Western blot analysis showed an obvious increase in expression level of CGRP in TGs of TN group compared with sham group, which was downregulated by TMP treatment (P < 0.05). These results suggested that TMP might have a therapeutic potential for the treatment of TN through regulating CGRP expression in the TGs.


Asunto(s)
Hiperalgesia/tratamiento farmacológico , Pirazinas/farmacología , Neuralgia del Trigémino/tratamiento farmacológico , Animales , Constricción , Masculino , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Ganglio del Trigémino/fisiopatología
11.
Biochim Biophys Acta ; 1840(7): 2128-38, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24637074

RESUMEN

BACKGROUND: The smoothened (SMO) receptor, one of the Class F G protein coupled receptors (GPCRs), is an essential component of the canonical hedgehog signaling pathway which plays a key role in the regulation of embryonic development in animals. The function of the SMO receptor can be modulated by small-molecule agonists and antagonists, some of which are potential antitumour agents. Understanding the binding mode of an antagonist in the SMO receptor is crucial for the rational design of new antitumour agents. METHODS: Molecular dynamics (MD) simulation and dynamical network analysis are used to study the dynamical structural features of SMO receptor. Metadynamics simulation and free energy calculation are employed to explore the binding mechanism between the antagonist and SMO receptor. RESULTS: The MD simulation results and dynamical network analysis show that the conserved KTXXXW motif in helix VIII has strong interaction with helix I. The α-helical extension of transmembrane 6 (TM6) is detected as part of the ligand-binding pocket and dissociation pathway of the antagonist. The metadynamics simulation results illustrate the binding mechanism of the antagonist in the pocket of SMO receptor, and free energy calculation shows the antagonist needs to overcome about 38kcal/mol of energy barrier to leave the binding pocket of SMO receptor. CONCLUSIONS: The unusually long TM6 plays an important role on the binding behavior of the antagonist in the pocket of SMO receptor. GENERAL SIGNIFICANCE: The results can not only profile the binding mechanism between the antagonist and Class F GPCRs, but also supply the useful information for the rational design of a more potential small molecule antagonist bound to SMO receptor.


Asunto(s)
Modelos Moleculares , Ftalazinas/química , Estructura Secundaria de Proteína , Receptores Acoplados a Proteínas G/química , Secuencia de Aminoácidos , Humanos , Simulación de Dinámica Molecular , Ftalazinas/farmacología , Unión Proteica , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal , Receptor Smoothened
12.
Front Public Health ; 12: 1295477, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38544722

RESUMEN

Objective: To investigate the relationship between Life's Essential 8 (LE8) and Phenotypic Age Acceleration (PhenoAgeAccel) in United States adults and to explore the impact of LE8 on phenotypic biological aging, thereby providing references for public health policies and health education. Methods: Utilizing data from the National Health and Nutrition Examination Survey (NHANES) conducted between 2007 and 2010, this cross-sectional study analyzed 7,339 adults aged 20 and above. Comprehensive assessments of LE8, PhenoAgeAccel, and research covariates were achieved through the integration of Demographics Data, Dietary Data, Laboratory Data, and Questionnaire Data derived from NHANES. Weighted generalized linear regression models and restricted cubic spline plots were employed to analyze the linear and non-linear associations between LE8 and PhenoAgeAccel, along with gender subgroup analysis and interaction effect testing. Results: (1) Dividing the 2007-2010 NHANES cohort into quartiles based on LE8 unveiled significant disparities in age, gender, race, body mass index, education level, marital status, poverty-income ratio, smoking and drinking statuses, diabetes, hypertension, hyperlipidemia, phenotypic age, PhenoAgeAccel, and various biological markers (p < 0.05). Mean cell volume demonstrated no intergroup differences (p > 0.05). (2) The generalized linear regression weighted models revealed a more pronounced negative correlation between higher quartiles of LE8 (Q2, Q3, and Q4) and PhenoAgeAccel compared to the lowest LE8 quartile in both crude and fully adjusted models (p < 0.05). This trend was statistically significant (p < 0.001) in the full adjustment model. Gender subgroup analysis within the fully adjusted models exhibited a significant negative relationship between LE8 and PhenoAgeAccel in both male and female participants, with trend tests demonstrating significant results (p < 0.001 for males and p = 0.001 for females). (3) Restricted cubic spline (RCS) plots elucidated no significant non-linear trends between LE8 and PhenoAgeAccel overall and in gender subgroups (p for non-linear > 0.05). (4) Interaction effect tests denoted no interaction effects between the studied stratified variables such as age, gender, race, education level, and marital status on the relationship between LE8 and PhenoAgeAccel (p for interaction > 0.05). However, body mass index and diabetes manifested interaction effects (p for interaction < 0.05), suggesting that the influence of LE8 on PhenoAgeAccel might vary depending on an individual's BMI and diabetes status. Conclusion: This study, based on NHANES data from 2007-2010, has revealed a significant negative correlation between LE8 and PhenoAgeAccel, emphasizing the importance of maintaining a healthy lifestyle in slowing down the biological aging process. Despite the limitations posed by the study's design and geographical constraints, these findings provide a scientific basis for the development of public health policies focused on healthy lifestyle practices. Future research should further investigate the causal mechanisms underlying the relationship between LE8 and PhenoAgeAccel and consider cross-cultural comparisons to enhance our understanding of healthy aging.


Asunto(s)
Envejecimiento , Diabetes Mellitus , Adulto , Humanos , Femenino , Masculino , Encuestas Nutricionales , Estudios Transversales , Escolaridad
13.
Epidemiol Health ; 46: e2024023, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38271958

RESUMEN

OBJECTIVES: In light of the rise in the global aging population, this study investigated the potential of the oxidative balance score (OBS) as an indicator of phenotypic age acceleration (PhenoAgeAccel) to better understand and potentially slow down aging. METHODS: Utilizing data from the National Health and Nutrition Examination Survey collected between 2001 and 2010, including 13,142 United States adults (48.7% female and 51.2% male) aged 20 and above, OBS and PhenoAgeAccel were calculated. Weighted generalized linear regression models were employed to explore the associations between OBS and PhenoAgeAccel, including a sex-specific analysis. RESULTS: The OBS demonstrated significant variability across various demographic and health-related factors. There was a clear negative correlation observed between the higher OBS quartiles and PhenoAgeAccel, which presented sex-specific. RESULTS: the negative association between OBS and PhenoAgeAccel was more pronounced in male than in female. An analysis using restricted cubic splines revealed no significant non-linear relationships. Interaction effects were noted solely in the context of sex and hyperlipidemia. CONCLUSIONS: A higher OBS was significantly associated with a slower aging process, as measured by lower PhenoAgeAccel. These findings underscore the importance of OBS as a biomarker in the study of aging and point to sex and hyperlipidemia as variables that may affect this association. Additional research is required to confirm these results and to investigate the biological underpinnings of this relationship.


Asunto(s)
Envejecimiento , Encuestas Nutricionales , Fenotipo , Humanos , Femenino , Masculino , Estudios Transversales , Adulto , Persona de Mediana Edad , Estados Unidos/epidemiología , Envejecimiento/fisiología , Anciano , Adulto Joven , Dieta/estadística & datos numéricos , Estrés Oxidativo , Conductas Relacionadas con la Salud
14.
Int J Mol Sci ; 14(10): 20171-88, 2013 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-24152435

RESUMEN

The electronic structures and excitation properties of dye sensitizers determine the photon-to-current conversion efficiency of dye sensitized solar cells (DSSCs). In order to understand the different performance of porphyrin dye sensitizers YD2 and YD2-o-C8 in DSSC, their geometries and electronic structures have been studied using density functional theory (DFT), and the electronic absorption properties have been investigated via time-dependent DFT (TDDFT) with polarizable continuum model for solvent effects. The geometrical parameters indicate that YD2 and YD2-o-C8 have similar conjugate length and charge transfer (CT) distance. According to the experimental spectra, the HSE06 functional in TDDFT is the most suitable functional for describing the Q and B absorption bands of porphyrins. The transition configurations and molecular orbital analysis suggest that the diarylamino groups are major chromophores for effective CT excitations (ECTE), and therefore act as electron donor in photon-induced electron injection in DSSCs. The analysis of excited states properties and the free energy changes for electron injection support that the better performance of YD2-o-C8 in DSSCs result from the more excited states with ECTE character and the larger absolute value of free energy change for electron injection.


Asunto(s)
Colorantes/química , Porfirinas/química , Sistema Solar/química , Absorción , Electrones
15.
Front Plant Sci ; 14: 1105374, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36743483

RESUMEN

Matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) can visualize the spatial distribution characteristics of molecules in tissues in situ, in which the matrix plays a key role. In this paper, we propose a platinum nanomaterial pre-coated matrix, which can be prepared in bulk by sputtering platinum nanoparticles onto slides using an ion sputterer and then used for MALDI-MS analysis by placing tissue sections on the matrix. We used this matrix for MALDI-MS imaging analysis of corn kernels and germinated wheat sections, and the results show that triacylglycerides were mainly distributed in the embryo of corn kernels and germinated wheat, and sugars were mainly distributed in the endosperm, with the highest content of disaccharides.It provides a simple and reliable experimental condition for analyzing the distribution of oligosaccharide and lipid components in plant tissues.

17.
RSC Adv ; 13(13): 8718, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36936857

RESUMEN

Expression of concern for 'Natural steroid-based cationic copolymers cholesterol/diosgenin-r-PDMAEMAs and their pDNA nanoplexes: impact of steroid structures and hydrophobic/hydrophilic ratios on pDNA delivery' by Zhao Wang et al., RSC Adv., 2021, 11, 19450-19460, DOI: https://doi.org/10.1039/D1RA00223F.

18.
Nutrients ; 15(20)2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37892552

RESUMEN

This study aimed to examine the relationship between daily total intake of water (DTIW) and handgrip strength (HGS) among US adults and to explore the impact of water intake on muscle function and health, providing a reference for public health policies and health education. Using the data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014, a cross-sectional survey design was adopted to analyze 5427 adults (48.37% female and 51.63% male) aged 20 years and above. DTIW was assessed using two non-consecutive 24 h dietary recall interviews, and the HGS level was measured using a Takei Dynamometer. Weighted generalized linear regression models and restricted cubic spline plots were used to analyze the linear and nonlinear associations between DTIW and HGS level and to conduct a gender subgroup analysis and an interaction effect test. The results showed that there were significant differences in HGS and other characteristics among different quartile groups of DTIW (p < 0.05). There was a significant nonlinear trend (exhibiting an inverted U-curve) between DTIW and HGS (p for nonlinear = 0.0044), with a cut-off point of 2663 g/day. Gender subgroup analysis showed that the nonlinear trend (exhibiting an inverted U-curve) was significant only in males (p for nonlinear = 0.0016), with a cut-off point of 2595 g/day. None of the stratified variables had an interaction effect on the association between DTIW and HGS (p for interaction > 0.05). In conclusion, this study found a nonlinear association between DTIW and HGS levels, as well as a gender difference. This finding provides new clues and directions for exploring the mechanism of the impact of DTIW on muscle function and health and also provides new evidence and suggestions for adults to adjust their water intake reasonably.


Asunto(s)
Ingestión de Líquidos , Fuerza de la Mano , Masculino , Humanos , Femenino , Estudios Transversales , Encuestas Nutricionales , Fuerza de la Mano/fisiología , Dieta
19.
Polymers (Basel) ; 15(22)2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-38006125

RESUMEN

Structural fiber-reinforced polymer (FRP) composite materials consisting of a polymer matrix reinforced with layers of high-strength fibers are used in numerous applications, including but not limited to spacecraft, vehicles, buildings, and bridges. Researchers in the past few decades have suggested the necessary integration of sensors (e.g., fiber optic sensors) in polymer composites to enable health monitoring of composites' performance over their service lives. This work introduces an innovative cognizant composite that can self-sense, compute, and implement decisions based on sensed values. It is a critical step towards smart, resilient infrastructure. We describe a method to fabricate textile sensors with flexible circuitry and a microcontroller within the polymer composite, enabling computational operations to take place in the composite without impacting its integrity. A microstructural investigation of the sensors showed that the amount of oxidative agent and soaking time of the fabric play a major role in the adsorption of polypyrrole (PPy) on fiberglass (FG). XPS results showed that the 10 g ferric chloride solution with 6 h of soaking time had the highest degree of protonation (28%) and, therefore, higher adsorption of PPy on FG. A strain range of 30% was achieved by examining different circuitry and sensor designs for their resistance and strain resolution under mechanical loading. A microcontroller was added to the circuit and then embedded within a composite material. This composite system was tested under flexural loading to demonstrate its self-sensing, computing, and actuation capabilities. The resulting cognizant composite demonstrated the ability to read resistance values and measure strain using the embedded microcontroller and autonomously actuate an LED light when the strain exceeds a predefined limit of 2000 µÎµ. The application of the proposed FRP system would provide in situ monitoring of structural composite components with autonomous response capabilities, as well as reduce manufacturing, production, and maintenance costs.

20.
Nanomaterials (Basel) ; 12(19)2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36234633

RESUMEN

Surface wrinkling instability in thin films attached to a compliant substrate is a well-recognized form of deformation under mechanical loading. The influence of the loading history on the formation of instability patterns has not been studied. In this work, the effects of the deformation history involving different loading sequences were investigated via comprehensive large-scale finite element simulations. We employed a recently developed embedded imperfection technique which is capable of direct numerical predictions of the surface instability patterns and eliminates the need for re-defining the imperfection after each analysis step. Attention was devoted to both uniaxial compression and biaxial compression. We show that, after the formation of wrinkles, the surface patterns could still be eliminated upon complete unloading of the elastic film-substrate structure. The loading path, however, played an important role in the temporal development of wrinkle configurations. With the same final biaxial state, different deformation histories could lead to different surface patterns. The finding brings about possibilities for creating variants of wrinkle morphologies controlled by the actual deformation path. This study also offers a mechanistic rationale for prior experimental observations.

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