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1.
Artigo em Inglês | MEDLINE | ID: mdl-35457764

RESUMO

Background: Few studies have examined the mental profiles and academic status of collegiate triathletes during training/competitive periods. We evaluated the changes in sleep quality, physical fatigue, emotional state, and academic stress among collegiate triathletes across training periods. Methods: Thirteen collegiate triathletes (19−26 years old) were recruited in this study. Mood state, sleep quality, degree of daytime sleepiness, subjective fatigue, and academic learning states were measured during the following five training periods: before national competitions for 3 months (3M-Pre Comp), 2 months (2M-Pre Comp), 1 month (1M-Pre Comp), 2 weeks (2wk-Pre Comp), and national competition (Comp) according to their academic/training schedule. Results: The academic stress index in 1M-Pre Comp (Final exam) was significantly higher than that in 3M-Pre Comp in these triathletes. No markedly significant differences were observed in overall mood state, sleep quality, individual degree of sleepiness, and fatigue among these five periods. However, the profiles mood state scale (POMS)-fatigue and -anger were lower in 2wk-Pre Comp than that in 1M-Pre com. The POMS-tension score in Comp was significantly higher than that in 3M-Pre Comp and 2M-Pre Comp. POMS-depression in Comp was lower than that in 1M-Pre Comp. Conclusion: We found that training volume was highest one month before a competition, and the academic stress is greatest during their final term exam period (1M-Pre Comp). After comprehensive assessment through analyzing POMS, PSQI, ESS, and personal fatigue (CIS), we found that the collegiate triathletes exhibited healthy emotional and sleep states (PSQI score < 5) across each training period, and our results suggest that these elite collegiate triathletes had proficient self-discipline, time management, and mental adjustment skills.


Assuntos
Qualidade do Sono , Esportes , Adulto , Fadiga , Humanos , Sono , Universidades , Adulto Jovem
2.
ACS Appl Mater Interfaces ; 9(44): 38436-38444, 2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-29028299

RESUMO

The extraordinary catalytic properties of enzymes are derived not only from their catalytic groups but also the unique properties of the active site. Tuning the microenvironment of synthetic catalysts is expected to enhance their performance if effective strategies can be developed. Interfacially cross-linked reverse micelles were prepared from three different cross-linkable surfactants. Pd nanoparticles were deposited in the core of the micelle for the catalytic hydrogenation of bicarbonate and CO2. The catalytic performance was found to depend heavily on the nature of the headgroup of the surfactant. Quaternary ammonium-based surfactants through ion exchange could bring bicarbonate to the catalytic center, whereas tertiary amine-based surfactants worked particularly well in CO2 hydrogenation, with turnover numbers an order of magnitude higher than that of commercially available Pd/C. The amines were proposed to bring CO2 to the proximity of the catalysts through reversible formation of carbamate, in the nanospace of the hydrophilic core of the cross-linked reverse micelle. In the bicarbonate reduction, additional improvement of the catalysts was achieved through localized sol-gel synthesis that introduced metal oxide near the catalytic metal.

3.
J Am Chem Soc ; 139(10): 3627-3630, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28244312

RESUMO

Studies on aminopolymer/oxide composite materials for direct CO2 capture from air have often focused on the prototypical poly(ethylenimine) (PEI) as the aminopolymer. However, it is known that PEI will oxidatively degrade at elevated temperatures. This degradation has been ascribed to the presence of secondary amines, which, when oxidized, lose their CO2 capture capacity. Here, we demonstrate the use of small molecule poly(propylenimine) (PPI) in linear and dendritic architectures supported in silica as adsorbent materials for direct CO2 capture from air. Regardless of amine loading or aminopolymer architecture, the PPI-based sorbents are found to be more efficient for CO2 capture than PEI-based sorbents. Moreover, PPI is found to be more resistant to oxidative degradation than PEI, even while containing secondary amines, as supported by FTIR, NMR, and ESI-MS studies. These results suggest that PPI-based CO2 sorbents may allow for longer sorbent working lifetimes due to an increased tolerance to sorbent regeneration conditions and suggest that the presence of secondary amines may not mean that all aminopolymers will oxidatively degrade.

4.
Nutrients ; 7(12): 10525-37, 2015 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-26694461

RESUMO

Tomato is a globally famous food and contains several phytonutrients including lycopene, ß-carotene, anthocyanin, and flavonoids. The increased temperature used to produce tomato juice, ketchup, tomato paste and canned tomato enhances the bioactive composition. We aimed to verify the beneficial effects of processed tomato juice from Kagome Ltd. (KOT) on hypolipidemic action in hamsters with hyperlipidemia induced by a 0.2% cholesterol and 10% lard diet (i.e., high-cholesterol diet (HCD)). Male Golden Syrian hamsters were randomly divided into two groups for treatment: normal (n = 8), standard diet (control); and experimental (n = 32), HCD. The 32 hamsters were further divided into four groups (n = 8 per group) to receive vehicle or KOT by oral gavage at 2787, 5573, or 13,934 mg/kg/day for six weeks, designated the HCD-1X, -2X and -5X groups, respectively. The efficacy and safety of KOT supplementation was evaluated by lipid profiles of serum, liver and feces and by clinical biochemistry and histopathology. HCD significantly increased serum levels of total cholesterol (TC), triacylglycerol (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), LDL-C/HDL-C ratio, hepatic and fetal TC and TG levels, and degree of fatty liver as compared with controls. KOT supplementation dose-dependently decreased serum TC, TG, LDL-C levels, LDL-C/HDL-C ratio, hepatic TC and TG levels, and fecal TG level. Our study provides experiment-based evidence to support that KOT may be useful in treating or preventing the onset of hyperlipidemia.


Assuntos
Sucos de Frutas e Vegetais/análise , Hiperlipidemias/dietoterapia , Solanum lycopersicum/química , Animais , Colesterol na Dieta/administração & dosagem , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Cricetinae , Dieta Hiperlipídica/efeitos adversos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Mesocricetus , Triglicerídeos/sangue
5.
Langmuir ; 31(49): 13350-60, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26602305

RESUMO

A mesoporous silica SBA-15 is modified with an array of amine-containing organosilanes including (i) propylamine, SiCH2CH2CH2NH2 (MONO), (ii) propylethylenediamine, SiCH2CH2CH2NHCH2CH2NH2 (DI), (iii) propyldiethylenetriamine, SiCH2CH2CH2NHCH2CH2NHCH2CH2NH2 (TRI), and (iv) propyltriethylenetetramine, SiCH2CH2CH2NHCH2CH2N(CH2CH2NH2)2 (TREN) and the low loading silane adsorbents (∼0.45 mmol silane/g) are evaluated for their CO2 adsorption properties, with a focus on gaining insight into the propensity for intramolecular vs intermolecular CO2 adsorption. Adsorption isotherms at low CO2 coverages are measured while simultaneously recording the heat evolved via a Tian-Calvet calorimeter. The results are compared on a silane molecule efficiency basis (mol CO2 adsorbed/mol silane) to assess the potential for intramolecular CO2 adsorption, employing two amine groups in a single silane molecule. As the number of amines in the silane molecule increases (MONO < DI < TREN ∼ TRI), the silane molecule efficiency is enhanced owing to the ability to intramolecularly capture CO2. Analysis of the CO2 uptake for samples with the surface silanols removed by capping demonstrates that cooperative uptake due to amine-CO2-silanol interactions is also possible over these adsorbents and is the primary mode of sorption for the MONO material at the studied low silane loading. As the propensity for intramolecular CO2 capture increases due to the presence of multiple amines in a single silane molecule (MONO < DI < TREN ∼ TRI), the measured heat of adsorption also increases. This study of various amine-containing silanes at low coverage is the first to provide significant, direct evidence for intramolecular CO2 capture in a single silane molecule. Furthermore, it provides evidence for the relative heats of adsorption for physisorption on a silanol laden surface (ca. 37 kJ/mol), a silanol-capped surface (ca. 25 kJ/mol), via amine-CO2-silanol interactions (ca. 46 kJ/mol), and via amine-CO2-amine interactions at low surface coverages (ca. 65 kJ/mol).

6.
J Am Chem Soc ; 136(15): 5579-82, 2014 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-24689781

RESUMO

Creation of synthetic catalysts with enzyme-like behavior is challenging despite strong interest in such systems. Extraction of tetrachloroaurate into the hydrophilic core of an interfacially cross-linked reverse micelle (ICRM) produced an artificial "metalloenzyme" with highly unusual catalytic properties. The ICRM pulled the substrate toward the catalytic metal, which converted it efficiently to the product that was rapidly ejected. These features enabled greatly reduced catalyst loading (30-100 times lower than typical levels used in literature examples), constant high reaction rate throughout the course of the reaction, lack of the hydrolyzed side product, and substrate selectivity unobserved in conventional gold catalysts.


Assuntos
Alcinos/química , Enzimas/química , Metaloproteínas/química , Mimetismo Molecular , Catálise
7.
Org Lett ; 14(3): 784-7, 2012 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-22273173

RESUMO

Cross-linking of the reverse micelles (RMs) of a triallylammonium surfactant afforded organic nanoparticles with introverted cationic groups. The cross-linked reverse micelles catalyzed size-selective biphasic reaction between sodium azide and alkyl bromides. Size selectivity of up to 9:1 was obtained for alkyl bromides with similar structures. The selectivity was influenced strongly by the size of the water pool and proposed to happen as a result of the "sieving" effect of the alkyl corona.


Assuntos
Micelas , Tensoativos/química , Azidas/química , Catálise , Estrutura Molecular
8.
Chin J Physiol ; 54(2): 79-86, 2011 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-21789888

RESUMO

Diabetes is characterized by elevated blood glucose levels and disturbed homeostasis of metabolic enzymes in whole-body. This study aimed to investigate the effect of ginger administration on altered blood glucose levels, intra- and extra-mitochondrial enzymes and tissue injuries in streptozotocin (STZ)-induced diabetic rats. Wistar strain rats (n = 30) were equally divided into 5 groups: normal control (NC), ginger treated (Gt, 200 mg/kg b.w. orally/30 days), diabetic control (DC, 50 mg/kg b.w.), diabetic plus ginger treated (D + Gt) and diabetic plus glibenclamide treated (D + Gli) groups. We found highly elevated blood glucose levels in the diabetic group, and the glucose levels were significantly (P < 0.001) lowered by ginger administration. Activities of intra- and extra-mitochondrial enzymes such as glucose-6-phosphate dehydrogenase (G6PD), succinate dehydrogenase (SDH), malate dehydrogenase (MDH) and glutamate dehydrogenase (GDH) were significantly (P < 0.01) decreased in the kidneys of the diabetic rats, while this was significantly reversed by 30 days of ginger treatment. We also observed consistent renal tissue damages in the diabetic rats; however, these injuries recovered in the ginger-treated diabetic rats as shown in histopathological studies. In this study, we demonstrated that an ethanolic extract of ginger could lower the blood glucose levels as well as improve activities of intra- and extra-mitochondrial enzymes in diabetic rats. Our results suggest that ginger extracts could be used as a nephro-protective supplement particularly to reverse diabetic-induced complications.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/prevenção & controle , Rim/efeitos dos fármacos , Extratos Vegetais/farmacologia , Zingiber officinale , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Citosol/efeitos dos fármacos , Citosol/enzimologia , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Modelos Animais de Doenças , Rim/metabolismo , Rim/patologia , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Ratos , Ratos Wistar
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