RESUMO
Multiple sclerosis (MS) is a primary inflammatory demyelinating disease associated with a probably secondary progressive neurodegenerative component. Impaired mitochondrial functioning has been hypothesized to drive neurodegeneration and to cause increased anaerobic metabolism in MS. The aim of our multicentre study was to determine whether MS patients had values of circulating lactate different from those of controls. Patients (n=613) were recruited, assessed for disability and clinically classified (relapsing-remitting, secondary progressive, primary progressive) at the Catholic University of Rome, Italy (n=281), at the MS Centre Amsterdam, The Netherlands (n=158) and at the S. Camillo Forlanini Hospital, Rome, Italy (n=174). Serum lactate levels were quantified spectrophotometrically with the analyst being blinded to all clinical information. In patients with MS serum lactate was three times higher (3.04±1.26mmol/l) than that of healthy controls (1.09±0.25mmol/l, p<0.0001) and increased across clinical groups, with higher levels in cases with a progressive than with a relapsing-remitting disease course. In addition, there was a linear correlation between serum lactate levels and the expanded disability scale (EDSS) (R(2)=0.419; p<0.001). These data support the hypothesis that mitochondrial dysfunction is an important feature in MS and of particular relevance to the neurodegenerative phase of the disease. Measurement of serum lactate in MS might be a relative inexpensive test for longitudinal monitoring of "virtual hypoxia" in MS and also a secondary outcome for treatment trials aimed to improve mitochondrial function in patients with MS.
Assuntos
Lactatos/sangue , Esclerose Múltipla/sangue , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/patologia , Esclerose Múltipla/patologia , Doenças Neurodegenerativas/sangue , Doenças Neurodegenerativas/patologiaRESUMO
The solvent regeneration in the post-combustion carbon capture process usually relies on steam from the power plant steam cycle. This heat duty is one of the challenges of energy consumption in PCC (Post-combustion Carbon Capture). However, this practice results in a significant energy penalty, leading to a substantial reduction in the capacity of the Power Plant, estimated to be between 19.5 and 40 %. This paper investigate the techno-economic feasibility of a solar-assisted regeneration process for the PCC industrial scale with diglycolamine solvent. The study aims to assess the impact of system configuration modifications, such as LVC (Lean Vapor Compression), SPCC (Solar Post-combustion Carbon Capture), and combinations of trough or compound solar collectors with LVC, on energy efficiency and overall plant performance. With 3E analysis for SPCC configuration results show that this configuration. However, reducing energy consumption and energy penalty factor, exhibits a decrease in exergy and exergoeconomic efficiency compared to the other configurations in terms of exergy and exergoeconomic aspects. However, the LVC + SCSS (Solar Combined Separator-Stripper) configuration demonstrates the best performance across the 3E aspects, resulting in a reduction energy penalty to 12.2 % and improvements of 38 % and 4.2 % in exergy and exergoeconomic factors, respectively.
RESUMO
Biologically inspired dry adhesion has recently become a research hot topic because of its practical significance in scientific research and instrumental technology. Yet, most of the current studies merely focus on borrowing the concept from some finer biological contact elements but lose sight of the foundation ones that play an equally important role in the adhesion functionality. Inspired by the bending behavior of the flexible foundation element of a gecko (lamellar skin) in attachment motion, in this study, a new type of dry adhesive structure was proposed, wherein a mushroom-shaped micropillar array behaving as a strongly adhesive layer was engineered on a discretely supported thin film. We experimentally observed and analytically modeled the structural deformation and found that the energy penalty could be largely reduced because of the partial shift from pillar bending to film bending. Such behavior is very analogous in functionality to the lamellar skin in a gecko's pads and is helpful in effectively limiting the damage of the contact interface, thus generating enhanced adhesion even on a rough surface.