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Medicine (Baltimore) ; 100(31): e26861, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34397862


ABSTRACT: Cardiac rehabilitation (CR) can improve clinical indicators in patients with cardiovascular diseases. The literature reports a 20% reduction in all-cause mortality and a 27% reduction in heart-disease mortality following CR. Although its clinical efficacy has been established, there is uncertainty whether center-based (CBCR) is more effective than home-based (HBCR) programs in acute and subacute phases. We aimed to verify significant differences in their effectiveness for the improvement of cardiopulmonary function by analyzing cardiopulmonary exercise (CPX) with laboratory tests following both CR programs.A single-center cohort study of 37 patients, recently diagnosed with underlying cardiovascular diseases, underwent CBCR(18) and HBCR(19). CBCR group performed a supervised exercise regimen at the CR center, for 1 hour, 2 to 3 days a week, for a total of 12 to18 weeks. HBCR group completed a self-monitored exercise program at home under the same guidelines as CBCR. Participants were evaluated by CPX with laboratory tests at 1- and 6-month, following the respective programs.There was no statistical significance in clinical characteristics and laboratory findings. Pre-post treatment comparison showed significant improvement in VO2/kg, minute ventilation/carbon dioxide production slope, breathing reserve, tidal volume (VT), heart rate recovery, oxygen consumption per heart rate, low-density lipoprotein (LDL), LDL/HDL ratio, total cholesterol, ejection fraction (EF) (P < .05). CBCR approach showed greater improvement with significance in VO2/kg, metabolic equivalents, and EF on between groups analysis (P < .05).The time effect of CPX test and laboratory data showed improvement in cardiopulmonary function and serum indicators for both groups. VO2/kg, metabolic equivalents, and EF were among the variables that showed significant differences between groups. In the acute and subacute phases of 1 to 6 months, the CBCR group showed a greater cardiac output improvement than the HBCR group.

Biomarcadores/sangue , Reabilitação Cardíaca , Doenças Cardiovasculares , Terapia por Exercício , Serviços de Assistência Domiciliar/estatística & dados numéricos , Centros de Reabilitação/estatística & dados numéricos , Reabilitação Cardíaca/métodos , Reabilitação Cardíaca/normas , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/terapia , Pesquisa Comparativa da Efetividade , Teste de Esforço/métodos , Terapia por Exercício/métodos , Terapia por Exercício/organização & administração , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , República da Coreia/epidemiologia , Testes de Função Respiratória/métodos , Testes de Função Respiratória/estatística & dados numéricos , Resultado do Tratamento
J Am Chem Soc ; 140(39): 12484-12492, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30165740


Metal (M) oxides are one of the most interesting and widely used solids, and many of their properties can be directly correlated to the local structural ordering within basic building units (BBUs). One particular example is the high-Ni transition metal layered oxides, potential cathode materials for Li-ion batteries whose electrochemical activity is largely determined by the cationic ordering in octahedra (e.g., the BBUs in such systems). Yet to be firmly established is how the BBUs are inherited from precursors and subsequently evolve into the desired ordering during synthesis. Herein, a multimodal in situ X-ray characterization approach is employed to investigate the synthesis process in preparing LiNi0.77Mn0.13Co0.10O2 from its hydroxide counterpart, at scales varying from the long-range to local individual octahedral units. Real-time observation corroborated by first-principles calculations reveals a topotactic transformation throughout the entire process, during which the layered framework is retained; however, due to preferential oxidation of Co and Mn over Ni, significant changes happen locally within NiO6 octahedra. Specifically, oxygen loss and the associated symmetry breaking occur in NiO6; as a consequence, Ni2+ ions become highly mobile and tend to mix with Li, causing high cationic disordering upon formation of the layered oxides. Only through high-temperature heat treatment, Ni is further oxidized, thereby inducing symmetry reconstruction and, concomitantly, cationic ordering within NiO6 octahedra. Findings from this study shed light on designing high-Ni layered oxide cathodes and, more broadly, various functional materials through synthetic control of the constituent BBUs.

Acta Crystallogr A Found Adv ; 74(Pt 5): 425-446, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30182931


Modern X-ray diffraction techniques are now allowing researchers to collect long-desired experimental verification data sets that are in situ, three-dimensional, on the same length scales as critical microstructures, and using bulk samples. These techniques need to be adapted for advanced material systems that undergo combinations of phase transformation, twinning and plasticity. One particular challenge addressed in this article is direct analysis of martensite phases in far-field high-energy diffraction microscopy experiments. Specifically, an algorithmic forward model approach is presented to analyze phase transformation and twinning data sets of shape memory alloys. In the present implementation of the algorithm, the crystallographic theory of martensite (CTM) is used to predict possible martensite microstructures (i.e. martensite orientations, twin mode, habit plane, twin plane and twin phase fractions) that could form from the parent austenite structure. This approach is successfully demonstrated on three single- and near-single-crystal NiTi samples where the fundamental assumptions of the CTM are not upheld. That is, the samples have elastically strained lattices, inclusions, precipitates, subgrains, R-phase transformation and/or are not an infinite plate. The results indicate that the CTM still provides structural solutions that match the experiments. However, the widely accepted maximum work criterion for predicting which solution of the CTM should be preferred by the material does not work in these cases. Hence, a more accurate model that can simulate these additional structural complexities can be used within the algorithm in the future to improve its performance for non-ideal materials.