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1.
NPJ Microgravity ; 8(1): 56, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36470890

RESUMO

Electrochemical energy conversion technologies play a crucial role in space missions, for example, in the Environmental Control and Life Support System (ECLSS) on the International Space Station (ISS). They are also vitally important for future long-term space travel for oxygen, fuel and chemical production, where a re-supply of resources from Earth is not possible. Here, we provide an overview of currently existing electrolytic energy conversion technologies for space applications such as proton exchange membrane (PEM) and alkaline electrolyzer systems. We discuss the governing interfacial processes in these devices influenced by reduced gravitation and provide an outlook on future applications of electrolysis systems in, e.g., in-situ resource utilization (ISRU) technologies. A perspective of computational modelling to predict the impact of the reduced gravitational environment on governing electrochemical processes is also discussed and experimental suggestions to better understand efficiency-impacting processes such as gas bubble formation and detachment in reduced gravitational environments are outlined.

2.
J Biomed Mater Res A ; 109(1): 77-91, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32421917

RESUMO

Gelatin is one of the most prominent biopolymers in biomedical material research and development. It is frequently used in hybrid hydrogels, which combine the advantageous properties of bio-based and synthetic polymers. To prevent the biological component from leaching out of the hydrogel, the biomolecules can be equipped with azides. Those groups can be used to immobilize gelatin covalently in hydrogels by the highly selective and specific azide-alkyne cycloaddition. In this contribution, we functionalized gelatin with azides at its lysine residues by diazo transfer, which offers the great advantage of only minimal side-chain extension. Approximately 84-90% of the amino groups are modified as shown by 1 H-NMR spectroscopy, 2,4,6-trinitrobenzenesulfonic acid assay as well as Fourier-transform infrared spectroscopy, rheology, and the determination of the isoelectric point. Furthermore, the azido-functional gelatin is incorporated into hydrogels based on poly(ethylene glycol) diacrylate (PEG-DA) at different concentrations (0.6, 3.0, and 5.5%). All hydrogels were classified as noncyctotoxic with significantly enhanced cell adhesion of human fibroblasts on their surfaces compared to pure PEG-DA hydrogels. Thus, the new gelatin derivative is found to be a very promising building block for tailoring the bioactivity of materials.


Assuntos
Azidas/química , Compostos de Diazônio/química , Gelatina/química , Hidrogéis/química , Lisina/química , Materiais Biocompatíveis , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular , Reação de Cicloadição , Fibroblastos/efeitos dos fármacos , Humanos , Polietilenoglicóis
3.
Healthc Financ Manage ; 68(6): 84-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24968630

RESUMO

Cleveland Clinic partnered with Harvard Business School to conduct a pilot project to explore the differences between time-driven activity-based costing (TDABC) and relative value unit costing. The goal was to determine whether TDABC could improve the accuracy of cost information and identify value-improvement opportunities for two types of heart-value procedures. Using TDABC, leaders gained a detailed look into process steps that could be consolidated, reduced, or performed with a lower cost mix of personnel.


Assuntos
Procedimentos Cirúrgicos Cardíacos/economia , Alocação de Custos/métodos , Administração Financeira de Hospitais/métodos , Valvas Cardíacas/cirurgia , Aquisição Baseada em Valor , Procedimentos Cirúrgicos Cardíacos/métodos , Humanos , Ohio , Estudos de Casos Organizacionais , Projetos Piloto , Análise e Desempenho de Tarefas , Fatores de Tempo
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