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The activity of ceramic honeycombs with varying material composition and degree of utilization is compared on a suitable model gas in a test plant. The tested honeycombs are standard products that have not been surface‐treated in any way. A propane‐air mixture was fed to the test plant and then oxidized in a high‐temperature furnace. The analysis of the conversion rate over the reaction temperature showed remarkable differences in activity. The honeycomb with the most promising results was further investigated with the exhaust gas from the drying process of a waste treatment plant. Finally, the activity of this honeycomb was assessed in a large‐scale trial in an existing running regenerative thermal oxidizer. 相似文献
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Maria Quitrio Sandra Simes Andreia Ascenso Manuela Carvalheiro Ana Paula Leandro Isabel Correia Ana Silveira Viana Pedro Faísca Lia Ascenso Jesús Molpeceres Maria Manuela Gaspar Catarina Pinto Reis 《International journal of molecular sciences》2021,22(8)
Insulin is a peptide hormone with many physiological functions, besides its use in diabetes treatment. An important role of insulin is related to the wound healing process—however, insulin itself is too sensitive to the external environment requiring the protective of a nanocarrier. Polymer-based nanoparticles can protect, deliver, and retain the protein in the target area. This study aims to produce and characterize a topical treatment for wound healing consisting of insulin-loaded poly-DL-lactide/glycolide (PLGA) nanoparticles. Insulin-loaded nanoparticles present a mean size of approximately 500 nm and neutral surface charge. Spherical shaped nanoparticles are observed by scanning electron microscopy and confirmed by atomic force microscopy. SDS-PAGE and circular dichroism analysis demonstrated that insulin preserved its integrity and secondary structure after the encapsulation process. In vitro release studies suggested a controlled release profile. Safety of the formulation was confirmed using cell lines, and cell viability was concentration and time-dependent. Preliminary safety in vivo assays also revealed promising results. 相似文献
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Use of coffee by‐products for the cultivation of Pleurotus citrinopileatus and Pleurotus salmoneo‐stramineus and its impact on biological properties of extracts thereof 下载免费PDF全文
Ana C. Freitas Mariana B. Antunes Dina Rodrigues Sérgio Sousa Manuela Amorim Maria F. Barroso Ana Carvalho Sandra M. Ferrador Ana M. Gomes 《International Journal of Food Science & Technology》2018,53(8):1914-1924
Incorporating spent coffee grounds (SCGs), a by‐product from coffee brewing, in growth substrate of beneficial edible mushrooms is an approach that has to be further studied due to its potential positive outcomes: environmental impact mitigation, production costs reduction and beneficial impact on consumer health. Hence, cultivation of Pleurotus citrinopileatus and Pleurotus salmoneo‐stramineus was tested using SCG which enabled maximum production yield of P. citrinopileatus which was of 25.1% (w/w). Variable antidiabetic potential was observed between aqueous and enzymatic extracts (3.8%–29% inhibition) regardless species and substrates, whereas aqueous extract of P. citrinopileatus grown in substrate without SCG stood out presenting the highest antioxidant activity and inhibition activity of angiotensin I‐converting enzyme (IC50 = 123 μg mL?1). Ethanolic and aqueous extracts of both Pleurotus species grown in the presence or absence of SGC proved to be an interesting prebiotic source for growth of Bifidobacterium animalis Bo in comparison with fructooligosaccharides (FOS). 相似文献
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Manuela Coromaldi 《The International journal of environmental studies》2020,77(4):619-635
ABSTRACT This paper examines the welfare effect of inter- and intra-seasonal weather shocks using a nationally representative dataset. Results show that both rainfall and maximum temperature variability appear to exert a negative impact on the considered outcomes. Higher between-years average of rainfall implies an increase in income. This impact is nonlinear when the shock is computed over shorter reference periods and is higher in the upper tail of the income distribution. Moreover, small levels of rainfall variability have a positive effect on income, but only up to a certain threshold, after which the effect becomes negative. There is a nonlinear relationship between welfare outcomes and the first two moments of the maximum temperature distribution. Agricultural extension services, access to rural credit and use of sustainable land management practices (SLM) are crucial to mitigating the negative welfare effects. 相似文献
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Milena Salvo Valentina Casalegno Manuela Suess Laura Gozzelino Christian Wilhelmi 《Ceramics International》2018,44(11):12081-12087
IR pulsed laser radiation in air was applied to Si3N4 and Invar to obtain reliable Si3N4/Si3N4 and Si3N4/Invar adhesive bonded components. The laser pre-treatment produced a homogeneous nanostructured oxide layer on the surfaces, which effectively increased the adhesion at the adhesive/adherends interface and led to cohesive failure in the joining material. The mechanical strength of Si3N4/ Si3N4 and Si3N4/Invar joined components was measured, with and without laser nanostructuring, before and after thermal cycling from room temperature to 50?K, and it resulted that the exposure to extremely low temperatures did not affect the mechanical integrity of the joints. It was also demonstrated that this laser pre-treatment did not alter the mechanical properties of the ceramic substrate. 相似文献
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Patrizia Pignataro Manuela Dicarlo Roberta Zerlotin Chiara Zecca Maria Teresa DellAbate Cinzia Buccoliero Giancarlo Logroscino Silvia Colucci Maria Grano 《International journal of molecular sciences》2021,22(4)
Irisin, the circulating peptide originating from fibronectin type III domain-containing protein 5 (FNDC5), is mainly expressed by muscle fibers under peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) control during exercise. In addition to several beneficial effects on health, physical activity positively affects nervous system functioning, particularly the hippocampus, resulting in amelioration of cognition impairments. Recently, FNDC5/irisin detection in hippocampal neurons and the presence of irisin in the cerebrospinal fluid opened a new intriguing chapter in irisin history. Interestingly, in the hippocampus of mice, exercise increases FNDC5 levels and upregulates brain-derived neurotrophic factor (BDNF) expression. BDNF, displaying neuroprotection and anti-inflammatory effects, is mainly produced by microglia and astrocytes. In this review, we discuss how these glial cells can morphologically and functionally switch during neuroinflammation by modulating the expression of a plethora of neuroprotective or neurotoxic factors. We also focus on studies investigating the irisin role in neurodegenerative diseases (ND). The emerging involvement of irisin as a mediator of the multiple positive effects of exercise on the brain needs further studies to better deepen this issue and the potential use in therapeutic approaches for neuroinflammation and ND. 相似文献