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1.
Rev. bras. med. esporte ; 28(6): 624-627, Nov.-Dec. 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1376732

RESUMEN

ABSTRACT Introduction The key objective of aerobic exercise is enhancing cardiorespiratory endurance. On the national gymnastics plan implementation, the idea of lifelong sports was gradually accepted by the masses, and the aerobic gymnastics concept was sweeping the world. Objective Analyze the cardiorespiratory endurance responses in female college students under different frequencies in aerobic exercise. Methods 20 female professors and civilian women were randomly selected and divided into two groups. The experimental group performed 45 and 90 minutes of aerobic exercise to analyze changes in cardiopulmonary function before and after each exercise. Results After 16 weeks of aerobic exercise with different loads, all young women who had participated in the program training showed a significant increase in vital capacity and maximal oxygen uptake capacity. The vital capacity of the 90-min aerobic exercise group was significantly higher than that of the 45-min aerobic exercise group (P<0.05). Conclusion The establishment of a cardiorespiratory endurance response model can accurately analyze the effects of different aerobic exercise frequencies on cardiorespiratory endurance. Evidence Level II; Therapeutic Studies - Investigating the results.


RESUMO Introdução O principal objetivo do exercício aeróbico é melhorar a resistência cardiorrespiratória. Com a implementação do plano nacional de ginástica, a ideia de esportes para toda a vida é gradualmente aceita pelas massas e o conceito de ginástica aeróbica está popularizando-se. Objetivo Analisar as respostas de resistência cardiorrespiratória em estudantes universitárias sob distintas frequências no exercício aeróbico. Métodos 20 jovens professoras e mulheres civis foram aleatoriamente selecionadas e divididas em dois grupos. O grupo experimental executou exercícios aeróbicos de 45 e 90 minutos, sob análise das alterações na função cardiopulmonar antes e depois de cada exercício. Resultados Após 16 semanas de exercício aeróbico com diferentes cargas, todas as mulheres jovens que participaram do treinamento mostraram um aumento significativo na capacidade vital e na capacidade máxima de absorção de oxigênio. A capacidade vital do grupo de exercícios aeróbicos de 90 minutos foi significativamente maior do que a do grupo de exercícios aeróbicos de 45 minutos (P<0,05). Conclusão O estabelecimento de um modelo de resposta de resistência cardiorrespiratória pode analisar com precisão os efeitos de diferentes frequências de exercício aeróbico sobre a resistência cardiorrespiratória. Nível de evidência II; Estudos Terapêuticos - Investigação de Resultados.


RESUMEN Introducción El objetivo principal del ejercicio aeróbico es mejorar la resistencia cardiorrespiratoria. Con la puesta en marcha del plan nacional de gimnasia, la idea de los deportes de por vida es gradualmente aceptada por las masas y el concepto de la gimnasia aeróbica está popularizándose en todo el mundo. Objetivo Analizar las respuestas de resistencia cardiorrespiratoria en estudiantes universitarias bajo diferentes frecuencias en el ejercicio aeróbico. Métodos Se seleccionaron al azar 20 profesoras jóvenes y mujeres civiles y se dividieron en dos grupos. El grupo experimental realizó ejercicios aeróbicos de 45 y 90 minutos, bajo el análisis de los cambios en la función cardiopulmonar antes y después de cada ejercicio. Resultados Tras 16 semanas de ejercicio aeróbico con diferentes cargas, todas las mujeres jóvenes que participaron en el entrenamiento mostraron un aumento significativo de la capacidad vital y de la capacidad máxima de captación de oxígeno. La capacidad vital del grupo de ejercicio aeróbico de 90 minutos fue significativamente mayor que la del grupo de ejercicio aeróbico de 45 minutos (P<0,05). Conclusión El establecimiento de un modelo de respuesta a la resistencia cardiorrespiratoria puede analizar con precisión los efectos de diferentes frecuencias de ejercicio aeróbico sobre la resistencia cardiorrespiratoria. Nivel de evidencia II; Estudios terapéuticos - Investigación de resultados.

2.
Artículo en Inglés | MEDLINE | ID: mdl-36231584

RESUMEN

Inbound tourism has an important impact on regional eco-efficiency. This paper uses the panel data of 31 provincial administrative units in China from 2005 to 2019; uses the improved DEA model to measure the regional ecological efficiency; and uses the panel threshold model to investigate input, output, and efficiency from the perspective of green technology innovation. Then, it explores the heterogeneous effects of inbound tourism on ecological efficiency. This paper finds that cross-border tourism has a positive impact on the ecological efficiency of tourist destinations. However, the degree of influence varies and will be changed with the level of regional green innovation. The main conclusions are as follows: (1) From an overall perspective, inbound tourism has a significant positive effect on ecological efficiency. (2) With the increase in green innovation investment and output, the promotion effect of inbound tourism on regional ecological efficiency first increases and then decreases. (3) The higher the green innovation efficiency, the greater the promotion effect of inbound tourism on ecological efficiency. Therefore, the Chinese government should encourage the development of inbound tourism, adopt greener innovative technologies that are cleaner and more environmentally friendly, and enhance the welfare effect of tourism on green economy.


Asunto(s)
Eficiencia , Turismo , China , Desarrollo Económico , Invenciones , Inversiones en Salud
3.
Angew Chem Int Ed Engl ; 61(29): e202205633, 2022 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-35502463

RESUMEN

Here, we combined the merits of emergent excitation-dependent (ExD) emission and circularly polarized luminescence to develop an excitation-dependent circularly polarized luminescence (ExD CPL) material showing unique features. A series of acylhydrazones based on a chiral tartaric skeleton was designed and found to self-assemble into helical nanostructures through non-covalent bonds. The helical assemblies showed ExD CPL due to the cooperation of chirality transfer and excited state intramolecular proton transfer (ESIPT). Remarkably, not only the emission wavelength could be tuned by the excitation wavelength but the handedness of CPL could be modulated in an inverted or ON/OFF manner as well, thus leading to the first example of an ExD inverted or ON/OFF switchable CPL system. Time-dependent density functional theory (TD-DFT) calculations were carried out to explain the inversion of ExD CPL. This work provided a new insight into the unprecedented handedness controllable ExD CPL, which showcased a new paradigm of the advanced CPL materials.


Asunto(s)
Luminiscencia , Teoría Funcional de la Densidad , Tartratos
4.
Nanoscale ; 14(3): 1001-1007, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-35024717

RESUMEN

How dissymmetrical tails (i.e. tails of different lengths) in one lipid molecule exert an impact on the structure and properties of the resulting assembly is an intriguing issue in both biological and material senses. However, the underlying mechanism that engenders such phenomena is still obscure, which prompted us to unmask it by exploring the self-assembly behaviours of artificial building blocks comprising dissymmetrical tails. Here, a series of Fmoc-protected ornithine lipids with dissymmetrical alkyl tails was designed and the dissymmetry of the two tails was found to hierarchically tune the self-assembled nanostructures from nanotubes to bundles and nanotwists. With the Fmoc-headgroup employed as a chromophorous probe, it was revealed that the alkyl chain dissymmetry controlled the interacting modes of van der Waals interactions between alkyl tails, π-π stacking between Fmoc motifs and hydrogen bonding formed by the three amide bonds in lipid bilayers. The counterbalance between those noncovalent interactions was responsible for such remarkable tuning ability towards self-assembly and emissive behaviours of the lipids, including circularly polarized light emission. This work provides insight into dissymmetrical tails-regulated biological structures and functions of natural lipids, and also sets up a novel strategy of rationally modulating chiral and emissive properties of supramolecular materials, i.e., tunable CPL materials, by exploitation of the tail dissymmetry.


Asunto(s)
Nanoestructuras , Nanotubos , Enlace de Hidrógeno , Ornitina
5.
ACS Appl Mater Interfaces ; 14(1): 1765-1773, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-34965725

RESUMEN

As the medium for self-assembly processes, solvents strongly influence the supramolecular assemblies via specific solute-solvent interactions, which may result in effective modulation of properties, self-assembled nanostructures, and functions through varying the solvent. Here, two kinds of pyridine-cyanostilbene functionalized chiral amphiphiles (l/d-PyPhG and l-PyG) were designed, and their self-assembly behaviors in different solvents were investigated. It was found that both amphiphiles formed gels in dimethyl sulfoxide (DMSO) and self-assembled into right-handed nanotwists, while they formed suspensions in ethanol consisting of left-handed nanotubes. Although the molecular chirality in the compounds remained unchanged in the two solvents, the nanoassemblies showed opposite handedness at the nanoscale together with opposite circular dichroism (CD) and circularly polarized luminescence (CPL) signals. Furthermore, when the amphiphiles were co-assembled with an achiral dye, it was found that efficient energy transfer took place in the systems composed of nanotubes rather than those composed of nanotwists. Therefore, by assembling molecules with the same molecular chirality in different solvents, a selective formation of helical nanotubes or nanotwists and the regulation of handedness as well as energy transfer efficiency were achieved.

6.
Neurosci Lett ; 749: 135710, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33577998

RESUMEN

Monocyte chemoattractant protein-1 (MCP-1) is reported to associate with the severity and development of Alzheimer's disease (AD). While a few studies have examined the association between the MCP-1 A-2518 G polymorphism and AD risk, no Chinese study has undertaken a study of this association. Therefore, a case-control study with 212 AD cases and 268 controls was designed in Chinese participants. Logistic regression analysis was utilized to probe the potential link between AD susceptibility and the MCP-1 A-2518 G polymorphism. We observed that the GG or GG + AG genotype was shown to elevate the risk of AD. Subgroup analysis revealed this increased risk effect was also presented in males, smokers, APOE ε4+ and those participants ≥ 65 years old. Notably, cross-over analysis found that this polymorphism interacted with smoking, contributing to the increased risk of AD. In addition, we found that the serum MCP-1 levels of AD patients were evidently higher than in controls. Furthermore, the MCP-1 A-2518 G polymorphism was linked with the serum MCP-1 levels of AD patients, but not controls. In conclusion, the MCP-1 A-2518 G polymorphism correlates with an elevated risk of AD and increased MCP-1 serum levels. The interaction between the MCP-1 A-2518 G polymorphism and smoking contributes to the increased risk for AD in Chinese Han individuals.


Asunto(s)
Enfermedad de Alzheimer/genética , Quimiocina CCL2/genética , Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple/genética , Anciano , Estudios de Casos y Controles , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad
7.
Langmuir ; 35(11): 4058-4067, 2019 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-30807183

RESUMEN

A novel CO2/N2 switchable n-decane-in-water emulsion was prepared, which is stabilized by a CO2/N2 switchable surfactant [ N'-dodecyl- N, N-dimethylacetamidine (DDMA)] in cationic form in combination with positively charged alumina nanoparticles at concentrations as low as 0.01 mM and 0.001 wt %, respectively. The particles do not adsorb at the oil-water interface but remain dispersed in the aqueous phase between surfactant-coated droplets. A critical zeta potential of the particles of ca. +18 mV is necessary for the stabilization of the novel emulsions, suggesting that the electrical double-layer repulsions between particles and between particles and oil droplets are responsible for their stability. By bubbling N2 into the emulsions, demulsification occurs following transformation of DDMA molecules from the surface-active cationic form to the surface-inactive neutral form and desorption from the oil-water interface. Bubbling CO2 into the demulsified mixtures, cationic DDMA molecules are re-formed, which adsorb to the droplet interfaces, ensuring stable emulsions after homogenization. Compared with Pickering emulsions and traditional emulsions, the amount of switchable surfactant and number of like-charged particles required for stabilization are significantly reduced, which is economically and environmentally benign for practical applications.

8.
Dalton Trans ; 47(46): 16696-16703, 2018 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-30427003

RESUMEN

The rational design strategy to construct lanthanide ion functionalized metal organic frameworks (MOFs) has attracted tremendous attention as they are promising candidates for developing novel luminescence materials and optical sensors owing to their intense, long-lived and tunable luminescence performances. In this work, a series of Eu3+/Tb3+ singly doped or codoped bismuth-based MOFs were prepared under in situ facile solvothermal conditions using BiOBr nanoplates as bismuth resources. A red-green-blue-based trichromatic white-light emission can be finely achieved by modulating the doping ratio of Eu3+/Tb3+ in the blue-emitting Bi-MOF host material and such photoluminescence tuning can also be realized by controlling the excitation wavelength. In addition, the Eu3+/Tb3+ singly incorporated Bi-MOF can serve as a multifunctional fluorescent probe for sensing Fe3+ and Cr2O72- ions in aqueous solution, as well as small organic pollutants of acetone molecules, and their sensing mechanisms have also been analyzed. These lanthanide ion functionalized Bi-MOF materials exhibit great potential in exploring white-light emitting devices and construction of supersensitive multifunctional sensors.

9.
Zhonghua Xin Xue Guan Bing Za Zhi ; 33(4): 315-9, 2005 Apr.
Artículo en Chino | MEDLINE | ID: mdl-15932659

RESUMEN

OBJECTIVE: To investigate the effect of spironolactone on left ventricular remodeling (LVRM) in patients with acute myocardial infarction. METHODS: In this multicentric, randomized, controlled study, spironolactone 40 mg/d was randomly administered in addition to the routine treatment for patients with AMI. During the 6 months the serum PIIINP, BNP and echocardiography were examined in all patients to assess myocardial fibrosis, LV function and volume. RESULTS: A total of 88 AMI patients entered the study came from 4 hospitals in Shijiazhuang. There were 43 patients with anterior MI and 45 with inferior MI. In anterior MI group 23 patients received spironolactone and 20 accepted the routine treatment. In inferior MI group 23 received spironolactone and 22 accepted the routine treatment. In anterior MI group: (1) At 3rd, 6th month PIIINP and BNP serum levels were significantly lower in the spironolactone group compared with those in control group [PIIINP (260.2 +/- 59.9) vs (328.0 +/- 70.3) ng/L, P = 0.001, (197.1 +/- 46.3) vs (266.7 +/- 52.4) ng/L, P < 0.001], [BNP (347.4 +/- 84.0) vs (430.1 +/- 62.9) ng/L, P < 0.001, (243.7 +/- 79.7) vs (334.6 +/- 62.8) ng/L, P < 0.001]; (2) There were smaller LVEDD and LVESD in spironolactone group compared with those in control group after 6 months intervention [(51.0 +/- 5.5) vs (55.6 +/- 4.5) mm, P = 0.005, (35.7 +/- 4.6) vs (39.1 +/- 5.6) mm, P = 0.046]. However, in inferior MI group: (1) There were no significant differences in PIIINP and BNP values between the two groups after 6 months intervention; (2) There were no significant differences in the LVEDD, LVESD, LVEF after 6 months treatment. CONCLUSION: (1) In patients with anterior MI, spironolactone combined with the routine treatment could inhibit myocardial fibrosis and left ventricular dilation and prevent LVRM. (2) In patients with inferior MI, no significant difference in prevention of LVRM was found between the spironolactone combined with the routine treatment and the routine treatment alone.


Asunto(s)
Infarto del Miocardio/tratamiento farmacológico , Revascularización Miocárdica , Espironolactona/uso terapéutico , Remodelación Ventricular/efectos de los fármacos , Femenino , Humanos , Masculino , Infarto del Miocardio/fisiopatología , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Procolágeno/sangre
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