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1.
Chem Commun (Camb) ; 59(88): 13191-13194, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37850458

RESUMEN

In this study, we synthesized two new two-dimensional (2D) covalent organic frameworks (COFs), COF-TA and COF-DP, by combining 4-connected D2h-symmetric and 2-connected non-centrosymmetric C2-symmetric building blocks. Unlike the typical sql topology, these COFs exhibit an unconventional kgm topology characterized by a favorable anti-parallel stacking arrangement, which results in a lower energy configuration. Notably, COF-DP, with its unique D-A-D structural motif and photosensitive properties, demonstrates a narrow band gap and excellent photothermal conversion capabilities, making it a promising material for photothermal imaging applications.

2.
Front Nutr ; 10: 1227027, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37560060

RESUMEN

Objective: Schisandra chinensis (Turcz.) Baill. (S. chinensis) is a Traditional Chinese medicinal herb that can be used both for medicinal purposes and as a food ingredient due to its beneficial properties, and it is enriched with a wide of natural plant nutrients, including flavonoids, phenolic acids, anthocyanins, lignans, triterpenes, organic acids, and sugars. At present, there is lack of comprehensive study or systemic characterization of nutritional and active ingredients of S. chinensis using innovative mass spectrometry techniques. Methods: The comprehensive review was conducted by searching the PubMed databases for relevant literature of various mass spectrometry techniques employed in the analysis of nutritional components in S. chinensis, as well as their main nutritional effects. The literature search covered the past 5 years until March 15, 2023. Results: The potential nutritional effects of S. chinensis are discussed, including its ability to enhance immunity, function as an antioxidant, anti-allergen, antidepressant, and anti-anxiety agent, as well as its ability to act as a sedative-hypnotic and improve memory, cognitive function, and metabolic imbalances. Meanwhile, the use of advanced mass spectrometry detection technologies have the potential to enable the discovery of new nutritional components of S. chinensis, and to verify the effects of different extraction methods on these components. The contents of anthocyanins, lignans, organic acids, and polysaccharides, the main nutritional components in S. chinensis, are also closely associated to its quality. Conclusion: This review will provide guidelines for an in-depth study on the nutritional value of S. chinensis and for the development of healthy food products with effective components.

3.
Rev. bras. med. esporte ; 29: e2022_0786, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1423421

RESUMEN

ABSTRACT Introduction Tai Ji is a martial art rich in traditional Chinese ethnic characteristics. Its flexible, free and open movements make its practice popular and esteemed by many female college students. However, there is a demand for experimental research on the impacts of the art on the physical and mental health of its college practitioners. Objective Verify the effects of Tai Ji practice on the physical health of university students. Methods This study used the methods of literature, experimental and mathematical statistics, through the influence of Tai Ji style number 24 on the physical health of female university students in different groups. Results The research shows that under the intervention of this style, with the same content, intensity, and time of exercise, the physical health of female college students in the low-fitness group was significantly improved. Conclusion Female college students in the medium and high fitness group improved their physical health indicators due to their physical preconditioning. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.


RESUMO Introdução O Tai Chi Chuan é uma arte marcial rica em características étnicas tradicionais chinesas. Seus movimentos flexíveis, livres e abertos fazem com que a sua prática seja popular e estimada por uma ampla gama de estudantes universitárias. Porém, há uma demanda de pesquisas experimentais sobre os impactos da arte sobre a saúde física e mental de seus praticantes universitários, no intuito de conduzir e orientar os seus praticantes durante a realização dos eventos esportivos. Objetivo Verificar os efeitos da prática de Tai Chi Chuan sobre a saúde física das estudantes universitárias. Métodos Este estudo utilizou os métodos da literatura, experimental e estatística matemática, através da influência do Tai Chi Chuan estilo número 24 na saúde física das estudantes universitárias femininas em diferentes grupos. Resultados A pesquisa mostra que sob a intervenção desse estilo, com o mesmo conteúdo, intensidade e tempo de exercício, a saúde física de estudantes universitárias do sexo feminino no grupo de baixa aptidão física foi significativamente aprimorada. Conclusão Estudantes universitárias do sexo feminino no grupo de aptidão física média e alta melhoraram seus indicadores de saúde física devido ao seu pré-condicionamento físico. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.


RESUMEN Introducción El Taichi Chuan es un arte marcial rico en características étnicas tradicionales chinas. Sus movimientos flexibles, libres y abiertos hacen que su práctica sea popular y apreciada por un amplio abanico de estudiantes universitarios. Sin embargo, existe una demanda de investigación experimental sobre los impactos del arte en la salud física y mental de sus practicantes universitarios, con el fin de conducir y guiar a sus practicantes durante los eventos deportivos. Objetivo Verificar los efectos de la práctica de Taichi Chuan en la salud física de estudiantes universitarios. Métodos Este estudio utilizó los métodos de la literatura, experimental y estadística matemática, a través de la influencia de Taichi Chuan estilo número 24 en la salud física de las estudiantes universitarias en diferentes grupos. Resultados La investigación demuestra que, bajo la intervención de este estilo, con el mismo contenido, intensidad y tiempo de ejercicio, mejoró significativamente la salud física de las estudiantes universitarias del grupo de baja forma física. Conclusión Las estudiantes universitarias del grupo de aptitud física media y alta mejoraron sus indicadores de salud física gracias a su preacondicionamiento físico. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

4.
PLoS One ; 17(3): e0262540, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35358194

RESUMEN

Climate is a dominant factor affecting the potential geographical distribution of species. Understanding the impact of climate change on the potential geographic distribution of species, which is of great significance to the exploitation, utilization, and protection of resources, as well as ecologically sustainable development. Betula platyphylla Suk. is one of the most widely distributed temperate deciduous tree species in East Asia and has important economic and ecological value. Based on 231 species distribution data points of Betula platyphylla Suk. in China and 37 bioclimatic, soil, and topography variables (with correlation coefficients < 0.75), the potential geographical distribution pattern of Betula platyphylla Suk. under Representative Concentration Pathway (RCP) climate change scenarios at present and in the 2050s and 2070s was predicted using the MaxEnt model. We analyzed the main environmental variables affecting the distribution and change of suitable areas and compared the scope and change of suitable areas under different climate scenarios. This study found: (1) At present, the main suitable area for Betula platyphylla Suk. extends from northeastern to southwestern China, with the periphery area showing fragmented distribution. (2) Annual precipitation, precipitation of the warmest quarter, mean temperature of the warmest quarter, annual mean temperature, and precipitation of the driest month are the dominant environmental variables that affect the potential geographical distribution of Betula platyphylla Suk. (3) The suitable area for Betula platyphylla Suk. is expected to expand under global warming scenarios. In recent years, due to the impact of diseases and insect infestation, and environmental damage, the natural Betula platyphylla Suk. forest in China has gradually narrowed. This study accurately predicted the potential geographical distribution of Betula platyphylla Suk. under current and future climate change scenarios, which can provide the scientific basis for the cultivation, management, and sustainable utilization of Betula platyphylla Suk. resources.


Asunto(s)
Cambio Climático , Ecosistema , Betula , China
5.
Entropy (Basel) ; 22(1)2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33285846

RESUMEN

Scientific experimental racks are an indispensable supporter in space stations for experiments with regard to meeting different temperature and humidity requirements. The diversity of experiments brings enormous challenges to the thermal control system of racks. This paper presents an indirect coupling thermal control single-phase fluid loop system for scientific experimental racks, along with fuzzy incremental control strategies. A dynamic model of the thermal control system is built, and three control strategies for it, with different inputs and outputs, are simulated. A comparison of the calculated results showed that pump speed and outlet temperature of the cold plate branch are, respectively, the best choice for the control variable and controlled variable in the controller. It showed that an indirect coupling thermal control fluid loop system with a fuzzy incremental controller is feasible for the thermal control of scientific experimental racks in space stations.

6.
Carbohydr Res ; 343(14): 2459-62, 2008 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-18635158

RESUMEN

Methyl 5-N-acetyl-7-O-acetyl-4-azido-2,3-didehydro-2,4-dideoxy-neuraminic acid (4azido-Neu2en5,7 Ac(2)1Me) was synthesized regioselectively starting from 4azido-Neu2en5Ac1Me in high yield. The transformation of 4azido-Neu2en5,7Ac(2)1Me to the corresponding thermodynamically stable 4azido-Neu2en5,9Ac(2)1Me via intramolecular acetyl migration was confirmed by single-crystal X-ray diffraction analysis. The proposed rearrangement mechanism is discussed.


Asunto(s)
Carbohidratos/química , Carbohidratos/síntesis química , Ácido N-Acetilneuramínico/análogos & derivados , Conformación de Carbohidratos , Cristalografía por Rayos X , Hidrólisis , Modelos Moleculares , Ácido N-Acetilneuramínico/síntesis química , Ácido N-Acetilneuramínico/química
7.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 1): o205, 2008 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-21581659

RESUMEN

Mol-ecules of the title compound, C(10)H(12)FNO(3), are nearly planar considering all non-H atoms with a mean deviation of 0.0288 Å. Mol-ecules are linked through inter-molecular N-H⋯O and N-H⋯F hydrogen bonds.

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