Five Poly(lactic acid) (PLA) film samples were analyzed to study the gas barrier behavior, thermal stability and mechanical performance for food packaging application. O₂, CO₂, N₂, N₂O, and C₂H₄ pure gases; Air; and Modified Atmosphere (MA, 79% N₂O/21% O₂) were used to analyze the influence of the chemical structure, storage temperature and crystalline phase on the gas barrier behavior. The kinetic of the permeation process was investigated at different temperatures, ranging from 5 °C to 40 °C. Annealing thermal treatment on the samples led to the crystalline percentage, influencing especially the gas solubility process. Thermal properties such as T and χ, and mechanical properties such as tensile strength and modulus were remarkably improved with surface PLA modification. A more pronounced reinforcing effect was noted in the case of metallization, as well as improved gas barrier performance. Tensile testing and tensile cycling tests confirmed the rigidity of the films, with about a 20% loss of elasticity after 25 cycles loading.
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http://dx.doi.org/10.3390/ma10080850 | DOI Listing |
Sci Transl Med
January 2025
Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder. Antiamyloid antibody treatments modestly slow disease progression in mild dementia due to AD. Emerging evidence shows that homeostatic dysregulation of the brain immune system, especially that orchestrated by microglia, plays an important role in disease onset and progression.
View Article and Find Full Text PDFBMC Microbiol
January 2025
Microbial Chemistry Department, Biotechnology Research Institute, National Research Center, Dokki, Giza, Egypt.
The red pigment was recovered from the S. phaeolivaceus GH27 isolate, which was molecularly identified using 16S rRNA gene sequencing and submitted to GenBank as OQ145635.1.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
December 2024
Anhui University of Chinese Medicine Hefei 230012, China Anhui Province Key Laboratory of Application and Transformation of Traditional Chinese Medicine in Prevention and Treatment of Major Pulmonary Diseases Hefei 230031, China Key Laboratory of Xin'an Medicine, Ministry of Education Hefei 230038, China.
This study aimed to investigate the mechanism by which Shegan Mahuang Decoction(SGMH) and its bitter Chinese herbs(BCHs) regulated the lung-gut axis through the bitter taste receptor 14(TAS2R14)/secretory immunoglobulin A(SIgA)/thymic stromal lymphopoietin(TSLP) to intervene in the epithelial cell barrier of cold asthma rats. Fifty SD rats were randomly divided into the following five groups: normal group, model group, dexamethasone group, SGMH group, and BCHs group. A 10% ovalbumin(OVA) solution was used to sensitize the rats via subcutaneous injection on both sides of the abdomen and groin, combined with 2% OVA atomization and cold(2-4 ℃) stimulation to induce a cold asthma model in rats.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, A-6020 Innsbruck, Austria.
Peptide bond formation from the pure protonated glycine dimer, H(Gly), and from the mixed protonated glycine-diglycine dimer, HGly(Gly), was recently found experimentally to occur in gas-phase experiments in the absence of any catalyst and especially under anhydrous conditions [, 2023, , 775]. In this contribution we further examine the conditions of such unimolecular reactions by means of density-functional theory calculations at the DFT/M06 2X/6-311G++(2df,p) level, focusing in particular on the role played by the protonation site. Two pathways, stepwise and concerted, are identified for the pure protonated dimer, and six pathways are examined for the mixed dimer.
View Article and Find Full Text PDFBackground: Although genetic factors have been identified in the pathogenesis of rheumatoid arthritis (RA), the concordance rate in monozygotic (MZ) twins is low, suggesting that other features contribute to disease development. Further, the relative contribution of such non-genetic elements in identical twins have not been characterized. Here, we aimed to measure differentiating host and microbial biomarkers of RA by studying MZ twins discordant for disease using a multi-omics approach.
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