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1.
Artigo em Inglês | MEDLINE | ID: mdl-36497824

RESUMO

Physical inactivity plays a role in the incidence of cardiovascular disease (CVD). Although the current guidelines for physical activity, such as the prescription of exercise, seek to combat CVD, attaining the recommended targets remains challenging. Tennis exercise has been proven to have a unique advantage in reducing the mortality of CVD, but little is known about the influence of playing tennis on impaired vascular endothelial function (VEF), which initiates CVD. Thus, this study aimed to investigate whether regular tennis participation could protect the VEF better than merely meeting the physical activity recommended by the current guidelines. A cross-sectional design was performed based on a sample of 38 healthy postmenopausal women who were matched for physical activity, of which 17 subjects had long-term tennis experience and 21 age-matched subjects regularly exercised but did not play tennis. The cardiovascular function and the body composition of all subjects were measured. We used cluster analysis to assess the overall health status. The modeling results showed that the tennis players performed better in terms of VEF than the nonplayers (10.55 ± 0.58 vs. 8.69 ± 0.52, p < 0.01, R2ad = 0.367), while the wall shear stress positively correlated with VEF (r = 0.505, p < 0.05), after controlling for age and physical activity levels. Regular tennis exercise may be a protective factor for VEF, and further study should be performed to research the role of hemodynamics in tennis exercise.


Assuntos
Tênis , Humanos , Feminino , Estudos Transversais , Composição Corporal , Exercício Físico , Comportamento Sedentário
2.
Plant Physiol Biochem ; 192: 162-171, 2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36242907

RESUMO

Lettuce is a common vegetable in hydroponic production. In this paper, a selenium (Se)-biofortification method was provided. The Se content, speciation, and the effects of different concentrations of selenate and selenite on lettuce growth and amino acids were investigated. The results showed that lettuce had strong ability to accumulate exogenous selenium, and inorganic Se could be effectively converted into organic Se. The proportion of organic Se in the shoots under treatment with 4 µmol L-1 selenite was 100%. Selenomethionine was the main organic Se, accounting for 51% (selenate) and 90% (selenite) of the total Se. Adding Se improves photosynthesis of lettuce and promotes growth. The growth with 2 µmol L-1 selenate and 4 µmol L-1 selenite was better than CK, and the shoot fresh weight was increased by 143.22% and 166.98%, respectively. Furthermore, the optimum Se application is 2 µmol L-1, and some areas can apply 4 µmol L-1 selenite. But Se-excessive areas are not recommended to grow selenium-rich foods. Therefore, lettuce has strong biofortification potential.

3.
Foods ; 11(14)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35885403

RESUMO

Yersinia enterocolitica is a dangerous foodborne human pathogen that mainly causes gastroenteritis. Ideal methods for the detection of pathogens in food should be rapid, sensitive, specific, and cost effective. To this end, novel in vitro nucleic acid identification methods based on clustered, regularly interspaced short palindromic repeats (CRISPR)-associated protein (Cas) endonuclease have received increasing attention. In this study, a simple, visual, and ultrasensitive method, based on CRISPR/Cas12a with recombinase polymerase amplification (RPA), was developed for the detection of Y. enterocolitica. The results show that a specific attachment invasion locus gene (ail) can be rapidly detected using a CRISPR/Cas12a-RPA-based system. Application of the method to raw pork, which was artificially infected with Y. enterocolitica, achieved an estimated detection limit of 1.7 CFU/mL in less than 45 min, and this was 100 times lower compared with qPCR. The results indicated that the CRISPR/Cas12a-RPA system has good potential for monitoring pathogenic Y. enterocolitica in the chilled meat supply chain.

4.
Nat Mater ; 20(7): 984-990, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33686276

RESUMO

All-solid-state lithium (Li) metal and lithium-ion batteries (ASSLBs) with inorganic solid-state electrolytes offer improved safety for electric vehicles and other applications. However, current inorganic ASSLB manufacturing technology suffers from high cost, excessive amounts of solid-state electrolyte and conductive additives, and low attainable volumetric energy density. Such a fabrication method involves separate fabrications of sintered ceramic solid-state electrolyte membranes and ASSLB electrodes, which are then carefully stacked and sintered together in a precisely controlled environment. Here we report a disruptive manufacturing technology that offers reduced manufacturing costs and improved volumetric energy density in all solid cells. Our approach mimics the low-cost fabrication of commercial Li-ion cells with liquid electrolytes, except that we utilize solid-state electrolytes with low melting points that are infiltrated into dense, thermally stable electrodes at moderately elevated temperatures (~300 °C or below) in a liquid state, and which then solidify during cooling. Nearly the same commercial equipment could be used for electrode and cell manufacturing, which substantially reduces a barrier for industry adoption. This energy-efficient method was used to fabricate inorganic ASSLBs with LiNi0.33Mn0.33Co0.33O2 cathodes and both Li4Ti5O12 and graphite anodes. The promising performance characteristics of such cells open new opportunities for the accelerated adoption of ASSLBs for safer electric transportation.

5.
J Colloid Interface Sci ; 585: 614-626, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33131783

RESUMO

Hyperbranched molecules are a kind of promising materials due to their unique structures. In this work, two hyperbranched molecules (GON and GOH) are used as effective inhibitors for Al alloys in NaCl solution. Their inhibitive performances are evaluated by electrochemical measurements and surface characterization. The results indicate that inhibition performances of GON and GOH are closely related to the concentrations, influenced by the combination of steric hindrance and bonding effects. At relatively low concentrations (0.03-0.10 mM), GON displays a more pronounced ability to inhibit corrosion than GOH, owing to more anchoring functional groups. Oppositely, GOH has good inhibition performance at higher concentrations (0.50-1.00 mM). The interaction between the Al electrode and GOH results in the formation of a more condenser protective film than GON at high concentrations. In addition, the adsorption mechanism of two hyperbranched molecules is revealed by theoretical calculations.

6.
Nat Mater ; 18(12): 1343-1349, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31501555

RESUMO

Metal fluoride conversion cathodes offer a pathway towards developing lower-cost Li-ion batteries. Unfortunately, such cathodes suffer from extremely poor performance at elevated temperatures, which may prevent their use in large-scale energy storage applications. Here we report that replacing commonly used organic electrolytes with solid polymer electrolytes may overcome this hurdle. We demonstrate long-cycle stability for over 300 cycles at 50 °C attained in high-capacity (>450 mAh g-1) FeF2 cathodes. The absence of liquid solvents reduced electrolyte decomposition, while mechanical properties of the solid polymer electrolyte enhanced cathode structural stability. Our findings suggest that the formation of an elastic, thin and homogeneous cathode electrolyte interphase layer on active particles is a key for stable performance. The successful operation of metal fluorides at elevated temperatures opens a new avenue for their practical applications and future successful commercialization.

7.
Nat Commun ; 9(1): 3478, 2018 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-30154472

RESUMO

Unconventional superconductivity arising from the interplay between strong spin-orbit coupling and magnetism is an intensive area of research. One form of unconventional superconductivity arises when Cooper pairs subjected to a magnetic exchange coupling acquire a finite momentum. Here, we report on a signature of finite momentum Cooper pairing in the three-dimensional topological insulator Bi2Se3. We apply in-plane and out-of-plane magnetic fields to proximity-coupled Bi2Se3 and find that the in-plane field creates a spatially oscillating superconducting order parameter in the junction as evidenced by the emergence of an anomalous Fraunhofer pattern. We describe how the anomalous Fraunhofer patterns evolve for different device parameters, and we use this to understand the microscopic origin of the oscillating order parameter. The agreement between the experimental data and simulations shows that the finite momentum pairing originates from the coexistence of the Zeeman effect and Aharonov-Bohm flux.

8.
Adv Mater ; 28(30): 6365-71, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27168478

RESUMO

Free-standing, high-capacity Li2 S electrodes with capacity loadings in the range from 1.5 to 3.8 mA h cm(-2) are produced by using infiltration of active materials into porous carbonized biomass sheets. The proposed electrode design can be effectively utilized for the low-cost fabrication of flexible lithium batteries with high specific energy.

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