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991.
In this brief note, a first assessment on the possibilities for thermal osmotic storage by harnessing the thermal dependence of the solubility of common salts as an alternative method to sensible heat storage is discussed. In a recent study it was found that such a dependence could be used to run a heat powered cycle (osmotic heat engine). The question raised then is whether that approach could be suitable for thermal energy storage as well. The attractiveness of such a possibility lies in the capability to store energy for an indefinite period of time without using expensive isolation systems if one considers that osmotic energy only is released when both streams with different salinities are brought together. Utilizing a simplified model, a comparative study with sensible heat storage was performed. It is shown that thermal osmotic storage via thermal precipitation of common salts could be an attractive option when long thermal storage (days) and compactness is desired.  相似文献   
992.
Cheeses are able to serve as suitable matrices for supplying probiotics to consumers, enabling appropriate conditions for bacteria to survive gastric transit and reach the gut, where they are assumed to promote beneficial processes. The present study aimed to evaluate the microbiological, immunological, and histological changes in the gut of Salmonella Enteritidis-challenged rats fed goat cheese supplemented with the probiotic strain Lactobacillus rhamnosus EM1107. Thirty male albino Wistar rats were randomly distributed into 5 experimental groups with 6 animals each: negative (NC) and positive (PtC) control groups, control goat cheese (CCh), goat cheese added with L. rhamnosus EM1107 (LrCh), and L. rhamnosus EM1107 only (EM1107). All animals, except NC group were challenged with Salmonella Enteritidis (109 cfu in 1 mL of saline through oral gavage). Microbial composition was assessed with high-throughput 16S rRNA sequencing by means of Illumina MiSeq (Illumina, San Diego, CA). Nuclear factor kappa B (NF-κB) from the animal cecum tissue was determined by real-time PCR and interleukins (TNF-α, IL-1β, IL-10, and IFN-γ) by means of ELISA. Myeloperoxidase and malondialdehyde levels were determined biochemically. The administration of the L. rhamnosus EM1107 probiotic strain, either as a pure culture or added to a cheese matrix, was able to reduce Salmonella colonization in the intestinal lumen and lessen tissue damage compared with rats from PtC group. In addition, the use of cheese for the probiotic strain delivery (LrCh) was associated with a marked shift in the gut microbiota composition toward the increase of beneficial organisms such as Blautia and Lactobacillus and a reduction in NF-κB expression. These findings support our hypothesis that cheeses might be explored as functional matrices for the efficacious delivery of probiotic strains to consumers.  相似文献   
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Transparent and translucent glass-ceramics (GCs) are found in an increasing number of domestic and high-technology applications. In this paper, we evaluated and optimized the effects of two-stage heat treatments on the resulting crystalline phases and microstructure of a glass of the SiO2–Li2O–P2O5–TiO2–CaO–ZnO–Al2O3 system. The objective was to develop a transparent nanostructured glass-ceramic (GC). After numerous heat treatment trials, we found that a long nucleation period of 72 h at 455 °C followed by a crystal growth treatment at 660 °C for 2 h resulted in a highly translucent GC having homogenously distributed nanocrystals. The relatively high amount of P2O5 (2.5 mol%) induced the formation of lithium disilicate as the main crystal phase. We thus developed a GC having crystals under 50 nm, with a high crystallized fraction (52%vol. Li2Si2O5 and 26% vol Li2SiO3), transmittance of approximately 80% in the visible spectrum for 1.2 mm thick specimens, nano hardness of 8.7 ± 0.1 GPa (load of 400 mN), a high elastic modulus of 138 ± 3 GPa as measured by nanoindentation, and good flexural strength (350 ± 40 MPa) as measured by ball-on-3 balls tests. Due to its high content of Li+, this GC has the potential to be chemically strengthened and can be further developed to be used in a number of applications, such as on displays of electronic devices.  相似文献   
996.
Advanced hybrid biocomposites are engineered from nylon 6, waste wood biosourced carbon (biocarbon) with a low content of synthetic fiber for lightweight auto-parts uses. The novel engineering process through direct injection molding of only 2 wt% synthetic fibers in the form of masterbatch with 20 wt% biocarbon, results outstanding performance of the resulting nylon biocomposites. Such uniquely developed biocomposites show tensile strength of 105 MPa and tensile modulus of 5.14 GPa with a remarkable heat deflection temperature (HDT) of 206 °C. The direct injection molding of synthetic fiber retains the length ≈3 times higher as compared to traditional extrusion and injection molding; resulting greater degree of entanglement and composite reinforcement effectiveness in the hybrid biocomposites. Highly dimensionally stable nylon 6 biocomposites with a very low coefficient of linear thermal expansion results through reinforcing ability of the sustainable biocarbon and small amount of synthetic fiber.  相似文献   
997.
Resveratrol (RSV) is a natural compound that displays several pharmacological properties, including anti-cancer actions. However, its clinical application is limited because of its low solubility and bioavailability. Here, the antiproliferative and anti-inflammatory activity of a series of phenylacetamide RSV derivatives has been evaluated in several cancer cell lines. These derivatives contain a monosubstituted aromatic ring that could mimic the RSV phenolic nucleus and a longer flexible chain that could confer a better stability and bioavailability than RSV. Using MTT assay, we demonstrated that most derivatives exerted antiproliferative effects in almost all of the cancer cell lines tested. Among them, derivative 2, that showed greater bioavailability than RSV, was the most active, particularly against estrogen receptor positive (ER+) MCF7 and estrogen receptor negative (ER-) MDA-MB231 breast cancer cell lines. Moreover, we demonstrated that these derivatives, particularly derivative 2, were able to inhibit NO and ROS synthesis and PGE2 secretion in lipopolysaccharide (LPS)-activated U937 human monocytic cells (derived from a histiocytoma). In order to define the molecular mechanisms underlying the antiproliferative effects of derivative 2, we found that it determined cell cycle arrest at the G1 phase, modified the expression of cell cycle regulatory proteins, and ultimately triggered apoptotic cell death in both breast cancer cell lines. Taken together, these results highlight the studied RSV derivatives, particularly derivative 2, as promising tools for the development of new and more bioavailable derivatives useful in the treatment of breast cancer.  相似文献   
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999.

In this work, two medium Mn steels (5.8 and 5.7 wt pct Mn) were subjected to a quenching and partitioning (Q&P) treatment employing a partitioning temperature which corresponded to the start of austenite reverse transformation (ART). The influence of a 1.6 wt pct Ni addition in one of the steels and cycle parameters on austenite stability and mechanical properties was also studied. High contents of retained austenite were obtained in the lower quenching temperature (QT) condition, which at the same time resulted in a finer microstructure. The addition of Ni was effective in stabilizing higher contents of austenite. The partitioning of Mn and Ni from martensite into austenite was observed by TEM–EDS. The partitioning behaviour of Mn depended on the QT condition. The lower QT condition facilitated Mn enrichment of austenite laths during partitioning and stabilization of a higher content of austenite. The medium Mn steel containing Ni showed outstanding values of the product of tensile strength (TS) and total elongation (TEL) in the lower QT condition and a higher mechanical stability of the austenite.

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