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1.
Support Care Cancer ; 32(6): 342, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739198

RESUMO

PURPOSE: Over the past few decades, the incidence of cancer among adolescents and young adults (AYA) has been increasing. The impact of behaviors, such as physical activity (PA) and nutrition, on disease progression, prognosis, and overall health and quality of life for AYA cancer survivors is of significant importance. This systematic review aims to evaluate the effectiveness of PA and diet interventions for AYA cancer survivors and to critically evaluate existing literature, gaps, and limitations. METHODS: A search of literature was conducted in PubMed, Science Direct, Scopus, and Google Scholar following the PRISMA guidelines. Twenty-two studies were included from online databases from 2012 to 2022, 13 of which were randomized controlled trials. RESULTS: Most interventions were related to PA, with only four studies including nutrition or Diet interventions. The interventions were generally feasible and acceptable to AYA cancer survivors, and digitally based PA interventions were commonly used. PA interventions mainly comprised aerobic and resistance training and were individualized. Overall, this review found various PA and diet interventions for AYA cancer survivors that were feasible and well-accepted, but gaps in knowledge and design still exist. CONCLUSIONS: This systematic review underscores the importance of conducting more research on diet interventions for YCS. PROSPERO REGISTRATION: https://www.crd.york.ac.uk/prospero/#aboutregpage.


Assuntos
Sobreviventes de Câncer , Dieta , Exercício Físico , Adolescente , Humanos , Adulto Jovem , Exercício Físico/fisiologia , Neoplasias , Qualidade de Vida
2.
Appl Opt ; 54(6): 1492-504, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25968218

RESUMO

A generalized transmission line method (TLM) that provides reflection and transmission calculations for a multilayer dielectric structure with coherent, partial coherent, and incoherent layers is presented. The method is deployed on two different application fields. The first application of the method concerns the thickness measurement of the individual layers of an organic light-emitting diode. By using a fitting approach between experimental spectral reflectance measurements and the corresponding TLM calculations, it is shown that the thickness of the films can be estimated. The second application of the TLM concerns the calculation of the external quantum efficiency of an organic photovoltaic with partially coherent rough interfaces between the layers. Numerical results regarding the short circuit photocurrent for different layer thicknesses and rough interfaces are provided and the performance impact of the rough interface is discussed in detail.

3.
J Phys Chem A ; 114(17): 5580-7, 2010 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-20384332

RESUMO

A theoretical investigation on the electronic structure of 4-dimethylamino-4'-nitrostilbene (DANS), 4-(dicyanomethylene)-2-methyl-6-p-(dimethylamino) styryl-4H-pyran (DCM), and their protonated forms is presented in an effort to rationalize recent experimental results on the tuning of the emitted color of organic light-emitting diodes through photochemically induced protonation. Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations have been carried out on the neutral and protonated forms of DANS and DCM, employing both the B3LYP and the CAM-B3LYP functionals. It was found that the CAM-B3LYP functional leads to better agreement than the B3LYP of the calculated with the experimental absorption lambda(max) for DANS, whereas B3LYP is more appropriate than CAM-B3LYP for DCM. The results of the calculations aid in a rationalization of the observed differences of the spectra of DANS and DCM upon protonation, and in particular those differences that make DANS a more attractive system for absorbance and emission tuning.

4.
Materials (Basel) ; 12(24)2019 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-31817961

RESUMO

Interest in the Mn+1AXn phases (M = early transition metal; A = group 13-16 elements, and X = C or N) is driven by their ceramic and metallic properties, which make them attractive candidates for numerous applications. In the present study, we use the density functional theory to calculate the elastic properties and the incorporation of lithium atoms in the 312 MAX phases. It is shown that the energy to incorporate one Li atom in Mo3SiC2, Hf3AlC2, Zr3AlC2, and Zr3SiC2 is particularly low, and thus, theoretically, these materials should be considered for battery applications.

5.
Respir Physiol Neurobiol ; 189(3): 513-20, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24013005

RESUMO

We investigated whether activity monitoring reliably reflects variations in oxygen transport and utilization during walking in COPD patients. Forty-two patients (14 in each GOLD stage II, III and IV) performed an incremental treadmill protocol to the limit of tolerance. Breath-by-breath gas exchange, central hemodynamic variables and activity monitoring were simultaneously recorded. Physiological variables and accelerometer outputs rose linearly with walking speeds. Strong correlations (r[interquartile range, IQR]) were found between treadmill walking intensity (WI: range 0.8-2.0 ms(-2)) and oxygen consumption (0.95 [IQR 0.87-0.97]), (range 7.6-15.5 ml kg(-1)min(-1)); minute ventilation (0.95 [IQR 0.86-0.98]), (range 20-37 l min(-1)); cardiac output (0.89 [IQR 0.73-0.94]), (range 6.8-11.5 l min(-1)) and arteriovenous oxygen concentration difference (0.84 [IQR 0.76-0.90]), (range 7.7-12.1 ml O2100 ml(-1)). Correlations between WI and gas exchange or central hemodynamic parameters were not different across GOLD stages. In conclusion, central hemodynamic, respiratory and muscle metabolic variations during incremental treadmill exercise are tightly associated to changes in walking intensity as recorded by accelerometry across GOLD stages II to IV. Interestingly, the magnitude of these associations is not different across GOLD stages.


Assuntos
Sistema Cardiovascular/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Respiração , Idoso , Calorimetria Indireta , Débito Cardíaco/fisiologia , Teste de Esforço , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Atividade Motora/fisiologia , Consumo de Oxigênio , Troca Gasosa Pulmonar , Caminhada/fisiologia
6.
Respir Physiol Neurobiol ; 181(3): 351-8, 2012 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-22484002

RESUMO

Exercise-induced dynamic hyperinflation and large intrathoracic pressure swings may compromise the normal increase in cardiac output (Q) in Chronic Obstructive Pulmonary Disease (COPD). Therefore, it is anticipated that the greater the disease severity, the greater would be the impairment in cardiac output during exercise. Eighty COPD patients (20 at each GOLD Stage) and 10 healthy age-matched individuals undertook a constant-load test on a cycle-ergometer (75% WR(peak)) and a 6min walking test (6MWT). Cardiac output was measured by bioimpedance (PhysioFlow, Enduro) to determine the mean response time at the onset of exercise (MRTon) and during recovery (MRToff). Whilst cardiac output mean response time was not different between the two exercise protocols, MRT responses during cycling were slower in GOLD Stages III and IV compared to Stages I and II (MRTon: Stage I: 45±2, Stage II: 65±3, Stage III: 90±3, Stage IV: 106±3s; MRToff: Stage I: 42±2, Stage II: 68±3, Stage III: 87±3, Stage IV: 104±3s, respectively). In conclusion, the more advanced the disease severity the more impaired is the hemodynamic response to constant-load exercise and the 6MWT, possibly reflecting greater cardiovascular impairment and/or greater physical deconditioning.


Assuntos
Débito Cardíaco/fisiologia , Exercício Físico/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Volume Sistólico/fisiologia , Adaptação Fisiológica , Idoso , Ciclismo , Estudos de Casos e Controles , Feminino , Frequência Cardíaca/fisiologia , Hemodinâmica , Humanos , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/classificação , Valores de Referência , Mecânica Respiratória , Índice de Gravidade de Doença , Caminhada
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