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91.
Polymer derived ceramic (PDCs) aerogels belonging to the Si–O–C–N system are synthesized by crosslinking a preceramic polymer in a diluted solution followed by supercritical or atmospheric drying and pyrolysis in inert (N2) or reactive (NH3/CO2) atmosphere. Accordingly, aerogels with hierarchical porosity ranging from some microns to few nanometers together with high specific surface area in the range 30–400 m2 g?1 have been obtained. Moreover, their surface contains a broad range of moieties (Si–OH, Si–NH, C=O, etc.) that can interact and bind metal ions thanks to electrostatic interactions. This combination of hierarchical porosity, high SSA, and broad range of chemical functionalities makes these PDCs aerogels interesting candidates for water purification. In this work, SiOC and SiCN aerogels have been tested as adsorbents for Cr(III)/(VI) ions from aqueous solutions with promising results for the SiOC aerogel pyrolyzed in N2 and the SiCN treated in NH3. Correlations and similarities among the Cr(VI)/(III) adsorption capacity with the main features of the porous substrates (SSA, N2 TPV, amount of free C, bulk density, isoelectric point, main IR peaks (Si–OH, OH, NH, C=O, C=C, Si–O, C–N, Si–N) have been investigated by applying the Principal Component Analysis (PCA).
  相似文献   
92.
The goal of the current study was to investigate potential cross-cultural differences in the covariation between two of the major dimensions of parenting behavior: control and warmth. Participants included 1,421 (51% female) 7- to 10-year-old (M = 8.29, SD = .67 years) children and their mothers and fathers representing 13 cultural groups in nine countries in Africa, Asia, Europe, the Middle East, and North and South America. Children and parents completed questionnaires and interviews regarding mother and father control and warmth. Greater warmth was associated with more control, but this association varied widely between cultural groups. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
93.
Oleuropein plays a key role as a pro-oxidant as well as an antioxidant in cancer. In this study, the activity of oleuropein, in an in vitro model of ovarian (OCCs) and breast cancer cells (BCCs) was investigated. Cell viability and cell death were analyzed. Oxidative stress was measured by CM-H2DCFDA flow cytometry assay. Mitochondrial dysfunction was evaluated based on mitochondrial reactive oxygen species (ROS) and GPX4 protein levels. Further, the effects on iron metabolism were analyzed by measuring the intracellular labile iron pool (LIP). We confirmed that high doses of oleuropein show anti-proliferative and pro-apoptotic activity on HEY and MCF-7 cells. Moreover, our results indicate that low doses of oleuropein impair cell viability without affecting the mortality of cells, and also decrease the LIP and ROS levels, keeping them unchanged in MCF-7 cells. For the first time, our data show that low doses of oleuropein reduce erastin-mediated cell death. Interestingly, oleuropein decreases the levels of intracellular ROS and LIP in OCCs treated with erastin. Noteworthily, we observed an increased amount of ROS scavenging enzyme GPX4 together with a consistent reduction in mitochondrial ROS, confirming a reduction in oxidative stress in this model.  相似文献   
94.
There is evidence that asbestos could play a role in the carcinogenesis of digestive cancers. The presence of asbestos fibres in histological samples from gastric, biliary, colon cancers has been reported, but the mechanism is still controversial. It has been hypothesised that asbestos reaches these sites, especially through contaminated water; however, some experimental studies have shown that the inhaled fibres are mobile, so they can migrate to many organs, directly or via blood and lymph flow. We report four unusual cases of colorectal cancers in patients with a long history of asbestos exposure who also developed synchronous or metachronous mesothelioma. We evaluated the roles of BRCA associated protein-1 (BAP1) and cyclin-dependent kinase inhibitor 2A (CDKN2A) in colon cancer and mesothelioma to support the hypothesis that BAP-1 and CDKN2A are tumour suppressor genes involved in disease progression, recurrence, or death in both digestive cancers and mesothelioma. Potentially, these markers may be used as predictors of worse prognosis, but we also stress the importance of clinical surveillance of exposed patients because asbestos could induce cancer in any organ.  相似文献   
95.
96.
The paper aims at proposing a model for the human resources evaluation as regards to a set of skills. Specifically, it starts sfrom the judgments expressed by a team of experts on the basis of their previous working experiences with the resource to be evaluated. Information arising from experts is successively handled by the analyst and aggregated to determine the resource suitability or unsuitability. The Dempster–Shafer theory is proposed here as an appropriate tool to deal with both the uncertainty of experts due to the incomplete knowledge about resources to be evaluated and that of the analyst to convert expert judgments in terms of resource suitability/unsuitability. Furthermore, the Yager rule is used to aggregate the available information simultaneously taking into account the uncertainty and the eventual conflict among the information sources. In addition, a parameter synthesizing the expertise of each candidate is suggested.  相似文献   
97.
The ZbTPI1 gene encoding triose phosphate isomerase (TIM) was cloned from a Zygosaccharomyces bailii genomic library by complementation of the Saccharomyces cerevisiae tpi1 mutant strain. The nucleotide sequence of a 1.5 kb fragment showed an open reading frame (ORF) of 746 bp, encoding a protein of 248 amino acid residues. The deduced amino acid sequence shares a high degree of homology with TIMs from other yeast species, including some highly conserved regions. The analysis of the promoter sequence of the ZbTPI1 revealed the presence of putative motifs known to have regulatory functions in S. cerevisiae. The GenBank Accession No. of ZbTPI1 is AF325852.  相似文献   
98.
Par j 1.0101 is one of the two major allergens of the Parietaria judaica (Pj) pollen, and its three-dimensional structure was built by three-dimensional structural homology modeling. The resultant model was used to identify putative IgE binding regions. Western blot analysis of gene fragmentation products showed that the 1 to 30 region was capable of binding specific IgE from a pool of sera (n = 30) of patients allergic to Pj pollen. Using the structural model as a guide, deletion and site-directed mutagenesis of the 1 to 30 region was performed, and the amino acids involved in IgE binding were identified. In addition, a synthetic peptide covering the 1 to 30 region was capable of binding human IgE without triggering histamine release from basophils of Pj allergic patients (n = 6) and thus represents a haptenic molecule with potential use as an immunotolerant agent. This epitope is also present on the Par j 2.0101 major allergen representing a common IgE epitope. It is an immunodominant epitope, since it was capable of inhibiting 30% of all specific IgE against the Pj major allergens, and therefore, it might be a candidate for the future development of immunotherapeutics.  相似文献   
99.
The striking clinical outcomes of antibody-based immunotherapy, through the inhibitors of cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and the programmed cell death protein-1 (PD-1) and its ligand (PD-L1) axis, have driven research aimed at identifying further clinically relevant tumor antigens that can serve as targets in solid tumors. B7 homolog 3 protein (B7-H3, also known as CD276) is a member of the B7 family overexpressed in tumor tissues, including non-small cell lung cancer (NSCLC), while showing limited expression in normal tissues, becoming an attractive and promising target for cancer immunotherapy. B7-H3 expression in tumors has been demonstrated to be associated with poor prognosis. In addition to its role in immune modulation, B7-H3 also promotes pro-tumorigenic functions such as tumor migration, invasion, metastases, resistance, and metabolism. In this review, we will provide an overview of this newly characterized immune checkpoint molecule and its development in the management of metastatic NSCLC.  相似文献   
100.
Shelf-life extension of Ricotta cheese coated with a chitosan/whey protein edible film and stored under modified atmosphere at 4 °C was evaluated. The chitosan/whey protein film had 35% and 21% lower oxygen and carbon dioxide permeability, respectively, and about three times higher water vapor permeability than film prepared with chitosan alone. Over a 30-day storage period, no differences in the pH of control and coated Ricotta cheeses were observed. While the titratable acidity of the control increased linearly during the first two weeks and remained constant for the rest of the storage period, the corresponding values for coated Ricotta cheese did not change significantly during the first 21 days and reached the acidity level (0.34 ± 0.02 milliequivalent/100 g of analyzed sample) of the control only on day 30. The viable numbers of lactic acid bacteria and mesophilic and psychrotrophic microorganisms were significantly lower (p < 0.05) in the chitosan/whey protein coated cheese, compared to the control, at each storage time. Our findings suggest a potential utility of chitosan/whey protein coatings to extend fresh dairy product shelf-life.  相似文献   
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