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1.
Front Rehabil Sci ; 4: 1084085, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36896249

RESUMO

Background: Use of standardized tools to assess balance and mobility limitations is a recommended practice in stroke rehabilitation. The extent to which clinical practice guidelines (CPGs) for stroke rehabilitation recommend specific tools and provide resources to support their implementation is unknown. Purpose: To identify and describe standardized, performance-based tools for assessing balance and/or mobility and describe postural control components challenged, the approach used to select tools, and resources provided for clinical implementation, in CPGs for stroke. Methods: A scoping review was conducted. We included CPGs with recommendations on the delivery of stroke rehabilitation to address balance and mobility limitations. We searched seven electronic databases and grey literature. Pairs of reviewers reviewed abstracts and full texts in duplicate. We abstracted data about CPGs, standardized assessment tools, the approach for tool selection, and resources. Experts identified postural control components challenged by each tool. Results: Of the 19 CPGs included in the review, 7 (37%) and 12 (63%) were from middle- and high-income countries, respectively. Ten CPGs (53%) recommended or suggested 27 unique tools. Across 10 CPGs, the most commonly cited tools were the Berg Balance Scale (BBS) (90%), 6-Minute Walk Test (6MWT) (80%), Timed Up and Go Test (80%) and 10-Meter Walk Test (70%). The tool most frequently cited in middle- and high-income countries was the BBS (3/3 CPGs), and 6MWT (7/7 CPGs), respectively. Across 27 tools, the three components of postural control most frequently challenged were underlying motor systems (100%), anticipatory postural control (96%), and dynamic stability (85%). Five CPGs provided information in varying detail on how tools were selected; only 1 CPG provided a level of recommendation. Seven CPGs provided resources to support clinical implementation; one CPG from a middle-income country included a resource available in a CPG from a high-income country. Conclusion: CPGs for stroke rehabilitation do not consistently provide recommendations for standardized tools to assess balance and mobility or resources to facilitate clinical application. Reporting of processes for tool selection and recommendation is inadequate. Review findings can be used to inform global efforts to develop and translate recommendations and resources for using standardized tools to assess balance and mobility post-stroke. Systematic Review Registration: https://osf.io/, identifier: 10.17605/OSF.IO/6RBDV.

2.
ACS Appl Mater Interfaces ; 10(19): 16238-16243, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29715003

RESUMO

All known materials wear under extended mechanical contacting. Superlubricity may present solutions, but is an expressed mystery in C-based materials. We report negative wear of carbon nitride films; a wear-less condition with mechanically induced material inflation at the nanoscale and friction coefficient approaching ultralow values (0.06). Superlubricity in carbon nitride is expressed as C-N bond breaking for reduced coupling between graphitic-like sheets and eventual N2 desorption. The transforming surface layer acts as a solid lubricant, whereas the film bulk retains its high elasticity. The present findings offer new means for materials design at the atomic level, and for property optimization in wear-critical applications like magnetic reading devices or nanomachines.

3.
Nanotechnology ; 27(14): 145601, 2016 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-26902955

RESUMO

Graphite-like hexagonal AlN (h-AlN) multilayers have been experimentally manifested and theoretically modeled. The development of any functional electronics applications of h-AlN would most certainly require its integration with other layered materials, particularly graphene. Here, by employing vdW-corrected density functional theory calculations, we investigate structure, interaction energy, and electronic properties of van der Waals stacking sequences of few-layer h-AlN with graphene. We find that the presence of a template such as graphene induces enough interlayer charge separation in h-AlN, favoring a graphite-like stacking formation. We also find that the interface dipole, calculated per unit cell of the stacks, tends to increase with the number of stacked layers of h-AlN and graphene.

4.
Dalton Trans ; 44(7): 3356-66, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25599815

RESUMO

We employ ab initio calculations to predict the equilibrium structure, stability, reactivity, and Raman scattering properties of sixteen different (H3C)nX(SiH3)3-n compounds (X = B, Al, Ga, In) with n = 0-3. Among this methylsilylmetal family, only the (H3C)3X members, i.e., trimethylboron (TMB), trimethylaluminum (TMA), trimethylgallium (TMG), and trimethylindium (TMI), are currently well-studied. The remaining twelve compounds proposed here open up a two-dimensional array of new possibilities for precursors in various deposition processes, and evoke potential applications in the chemical synthesis of other compounds. We infer that within the (H3C)nX(SiH3)3-n family, the compounds with fewer silyl groups (and consequently with more methyl groups) are less reactive and more stable. This trend is verified from the calculated cohesive energy, Gibbs free energy of formation, bond strength, and global chemical indices. Furthermore, we propose sequential reaction routes for the synthesis of (H3C)nX(SiH3)3-n by substitution of methyl by silyl groups, where the silicon source is the silane gas. The corresponding reaction barriers for these chemical transformations lie in the usual energy range typical for MOCVD processes. We also report the Raman spectra and light scattering properties of the newly proposed (H3C)nX(SiH3)3-n compounds, in comparison with available data of known members of this family. Thus, our computational experiment provides useful information for a systematic understanding of the stability/reactivity and for the identification of these compounds.

5.
J Phys Chem A ; 116(36): 9080-7, 2012 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-22894141

RESUMO

Corannulene has been a useful prototype for studying C-based nanostructures as well as surface chemistry and reactivity of sp(2)-hybridized carbon-based materials. We have investigated fluorination and hydrogenation of corannulene carrying out density functional theory calculations. In general, the fluorination is energetically more favorable than hydrogenation of corannulene. The substitution of the peripheral H atoms in the corannulene molecule by F atoms leads to a larger cohesive energy gain than when F (or H) atoms are bonded to the hub carbon and bridge carbon sites of this molecule. As expected for doped C-based nanostructures, the hydrogenation or fluorination significantly changes the HOMO-LUMO gap of the system. We have obtained HOMO-LUMO gap variations of 0.13-3.46 eV for F-doped and 0.38-1.52 eV for H-doped systems. These variations strongly depend on the concentration and position of the incorporated F/H atoms, instead of the structural stability of the doped systems. Considering these calculations, we avoid practical difficulties associated with the addition/substitution reactions of larger curved two-dimensional (2D) carbon nanostructures, and we obtain a comprehensive and systematic understanding of a variety of F/H 2D doped systems.

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