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1.
Abstract

Energy use efficiency in the drying of medicinal and aromatic plants is largely determined by weather conditions and process parameters. While the former are beyond control, the latter can be optimized. In order to achieve such optimization, different energy supply variants, based on typical operating conditions of batch-type grate drying in Thuringia, Germany, were analyzed. It was found that partial air recirculation and integration of heat pumps allow substantial savings in primary energy. However, under the constraint of German energy prices, significant savings in energy costs can only be achieved if combined heat and power generation systems are applied at the same time.  相似文献   
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To date, the results of studies which attempted to estimate residential water demand models have varied, but the source of these variations is not evident because the studies have applied different methodologies and data bases to different regions. The purpose of this paper is to develop models of residential water demand for watershed regions and test the null hypothesis that a single model is adequate to explain variations for all of the individual regions. Primary data collected from questionnaires and utility company records is used in a regression analysis to estimate a generalized water demand model for the state as well as one for each of the subregions. The null hypothesis is rejected which indicates that there are other factors which influence the demand for water and the use of a single model could result in biased estimates.  相似文献   
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Transdifferentiation of Schwann cells is essential for functional peripheral nerve regeneration after injury. By activating a repair program, Schwann cells promote functional axonal regeneration and remyelination. However, chronic denervation, aging, metabolic diseases, or chronic inflammatory processes reduce the transdifferentiation capacity and thus diminish peripheral nerve repair. It was recently described that the sphingosine-1-phosphate receptor (S1PR) agonist Fingolimod enhances the Schwann cell repair phenotype by activation of dedifferentiation markers and concomitant release of trophic factors resulting in enhanced neurite growth. Since Fingolimod targets four out of five S1PRs (S1P1, S1P3-5) possibly leading to non-specific adverse effects, identification of the main receptor(s) responsible for the observed phenotypic changes is mandatory for future specific treatment approaches. Our experiments revealed that S1P3 dominates and that along with S1P1 acts as the responsible receptor for Schwann cell transdifferentiation as revealed by the combinatory application of specific agonists and antagonists. Targeting both receptors reduced the expression of myelin-associated genes, increased PDGF-BB representing enhanced trophic factor expression likely to result from c-Jun induction. Furthermore, we demonstrated that S1P4 and S1P5 play only a minor role in the adaptation of the repair phenotype. In conclusion, modulation of S1P1 and S1P3 could be effective to enhance the Schwann cell repair phenotype and thus stimulate proper nerve repair.  相似文献   
5.
Glycyrrhizic acid (GA), a natural compound isolated from licorice (Glycyrrhiza glabra), has exhibited anti-inflammatory and anti-tumor effects in vitro. Dipotassium glycyrrhizinate (DPG), a dipotassium salt of GA, also has shown an anti-tumor effect on glioblastoma cell lines, U87MG and T98G. The study investigated the DPG effects in the melanoma cell line (SK-MEL-28). MTT assay demonstrated that the viability of the cells was significantly decreased in a time- and dose-dependent manner after DPG (IC50 = 36 mM; 24 h). DNA fragmentation suggested that DPG (IC50) induced cellular apoptosis, which was confirmed by a significant number of TUNEL-positive cells (p-value = 0.048) and by PARP-1 [0.55 vs. 1.02 arbitrary units (AUs), p-value = 0.001], BAX (1.91 vs. 1.05 AUs, p-value = 0.09), and BCL-2 (0.51 vs. 1.07 AUs, p-value = 0.0018) mRNA compared to control cells. The proliferation and wound-healing assays showed an anti-proliferative effect on DPG-IC50-treated cells, also indicating an inhibitory effect on cell migration (p-values < 0.001). Moreover, it was observed that DPG promoted a 100% reduction in melanospheres formation (p-value = 0.008). Our previous microRNAs (miRs) global analysis has revealed that DPG might increase miR-4443 and miR-3620 expression levels. Thus, qPCR showed that after DPG treatment, SK-MEL-28 cells presented significantly high miR-4443 (1.77 vs. 1.04 AUs, p-value = 0.02) and miR-3620 (2.30 vs. 1.00 AUs, p-value = 0.01) expression compared to control cells, which are predicted to target the NF-kB, CD209 and TNC genes, respectively. Both genes are responsible for cell attachment and migration, and qPCR revealed significantly decreased CD209 (1.01 vs. 0.54 AUs, p-value = 0.018) and TNC (1.00 vs. 0.31 AUs, p-value = 2.38 × 10−6) mRNA expression levels after DPG compared to untreated cells. Furthermore, the migration of SK-MEL-28 cells stimulated by 12-O-tetradecanoylphorbol-13-acetate (TPA) was attenuated by adding DPG by wound-healing assay (48 h: p-value = 0.004; 72 h: p-value = 7.0 × 10−4). In addition, the MMP-9 expression level was inhibited by DPG in melanoma cells stimulated by TPA and compared to TPA-treated cells (3.56 vs. 0.99 AUs, p-value = 0.0016) after 24 h of treatment. Our results suggested that DPG has an apoptotic, anti-proliferative, and anti-migratory effect on SK-MEL-28 cells. DPG was also able to inhibit cancer stem-like cells that may cause cerebral tumor formation.  相似文献   
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Nanoparticles of metal–organic frameworks (MOF NPs) are crystalline hybrid micro- or mesoporous nanomaterials that show great promise in biomedicine due to their significant drug loading ability and controlled release. Herein, we develop porous capsules from aggregate of nanoparticles of the iron carboxylate MIL-100(Fe) through a low-temperature spray-drying route. This enables the concomitant one-pot encapsulation of high loading of an antitumor drug, methotrexate, within the pores of the MOF NPs, and the collagenase enzyme (COL), inside the inter-particular mesoporous cavities, upon the formation of the capsule, enhancing tumor treatment. This association provides better control of the release of the active moieties, MTX and collagenase, in simulated body fluid conditions in comparison with the bare MOF NPs. In addition, the loaded MIL-100 capsules present, against the A-375 cancer cell line, selective toxicity nine times higher than for the normal HaCaT cells, suggesting that MTX@COL@MIL-100 capsules may have potential application in the selective treatment of cancer cells. We highlight that an appropriate level of collagenase activity remained after encapsulation using the spray dryer equipment. Therefore, this work describes a novel application of MOF-based capsules as a dual drug delivery system for cancer treatment.  相似文献   
8.
Background: Severe outcomes of COVID-19 account for up to 15% of all cases. The study aims to check if any gene variants related to cardiovascular (CVD) and pulmonary diseases (PD) are correlated with a severe outcome of COVID-19 in a Polish cohort of COVID-19 patients. Methods: In this study, a subset of 747 samples from unrelated individuals collected across Poland in 2020 and 2021 was used and whole-genome sequencing was performed. Results: The GWAS analysis of SNPs and short indels located in genes related to CVD identified one variant significant in COVID-19 severe outcome in the HADHA gene, while for the PD gene panel, we found two significant variants in the DRC1 gene. In this study, both potentially protective and risk variants were identified, of which variants in the HADHA gene deserve the most attention. Conclusions: This is the first study reporting the association between the HADHA and DRC1 genetic variants and COVID-19 severe outcome based on the cohort WGS analysis. Although all the identified variants are localised in introns, they may be correlated and therefore inherited along with other risk variants, potentially causative to severe outcome of COVID-19 but not discovered yet.  相似文献   
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Controlling coherent interaction between optical fields and quantum systems in scalable, integrated platforms is essential for quantum technologies. Miniaturise...  相似文献   
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