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991.
Paola Franco Marco Martino Vincenzo Palma Alice Scarpellini Iolanda De Marco 《International Journal of Hydrogen Energy》2018,43(43):19965-19975
In this paper, we present a study on the preparation of ceria nanopowder by Supercritical Antisolvent technique and its use as catalysts support for water gas shift reaction. The effect of the concentration of ceria precursor and the solution flow rate was evaluated on particle size and granulometric distribution. The increase of concentration led to an increase in the average particle size, whereas the solution flow rate had a negligible effect. The platinum/ceria catalyst was prepared by wet impregnation and fully characterized; SEM and TEM-EDX showed a mean particle size of around 50 nm and a good dispersion of the active component. The results of the activity tests highlighted a good performance of the SAS-derived catalyst, that showed higher CO conversion with respect to a catalyst obtained from commercial ceria nanopowder. 相似文献
992.
Machine Learning - Efficient omission of symmetric solution candidates is essential for combinatorial problem-solving. Most of the existing approaches are instance-specific and focus on the... 相似文献
993.
Ailma O. da Paixo Anaysa Paola Bolin Joo G. Silvestre Alice Cristina Rodrigues 《International journal of molecular sciences》2021,22(5)
Palmitic acid (PA), a saturated fatty acid enriched in high-fat diet, has been implicated in the development of sarcopenic obesity. Herein, we chose two non-cytotoxic concentrations to better understand how excess PA could impact myotube formation or diameter without inducing cell death. Forty-eight hours of 100 µM PA induced a reduction of myotube diameter and increased the number of type I fibers, which was associated with increased miR-206 expression. Next, C2C12 myotube growth in the presence of PA was evaluated. Compared to control cells, 150 µM PA reduces myoblast proliferation and the expression of MyoD and miR-206 and miR-133a expression, leading to a reduced number and diameter of myotubes. PA (100 µM), despite not affecting proliferation, impairs myotube formation by reducing the expression of Myf5 and miR-206 and decreasing protein synthesis. Interestingly, 100 and 150 µM PA-treated myotubes had a higher number of type II fibers than control cells. In conclusion, PA affects negatively myotube diameter, fusion, and metabolism, which may be related to myomiRs. By providing new insights into the mechanisms by which PA affects negatively skeletal muscle, our data may help in the discovery of new targets to treat sarcopenic obesity. 相似文献
994.
Stefano A. Serapian Alice Triveri Filippo Marchetti Matteo Castelli Prof. Giorgio Colombo 《ChemMedChem》2021,16(10):1593-1599
Advances in genomics and proteomics have unveiled an ever-growing number of key proteins and provided mechanistic insights into the genesis of pathologies. This wealth of data showed that changes in expression levels of specific proteins, mutations, and post-translational modifications can result in (often subtle) perturbations of functional protein–protein interaction networks, which ultimately determine disease phenotypes. Although many such validated pathogenic proteins have emerged as ideal drug targets, there are also several that escape traditional pharmacological regulation; these proteins have thus been labeled “undruggable”. The challenges posed by undruggable targets call for new sorts of molecular intervention. One fascinating solution is to perturb a pathogenic protein's expression levels, rather than blocking its activities. In this Concept paper, we shall discuss chemical interventions aimed at recruiting undruggable proteins to the ubiquitin proteasome system, or aimed at disrupting protein-protein interactions in the chaperone-mediated cellular folding machinery: both kinds of intervention lead to a decrease in the amount of active pathogenic protein expressed. Specifically, we shall discuss the role of computational strategies in understanding the molecular determinants characterizing the function of synthetic molecules typically designed for either type of intervention. Finally, we shall provide our perspectives and views on the current limitations and possibilities to expand the scope of rational approaches to the design of chemical regulators of protein levels. 相似文献
995.
996.
Richardson AN Pollak EA Williams D Agyekum AK Smith MA 《Journal of food protection》2012,75(5):884-888
Neonatal, premature, or very low birth weight infants fed reconstituted powdered infant formula contaminated with Cronobacter (Enterobacter sakazakii) may develop infections resulting in severe outcomes such as septicemia, necrotizing enterocolitis, meningitis, or death. Infants who recover from infection may have morbidities such as hydrocephalus, mental retardation, or developmental delays. Although increasing age appears to reduce susceptibility to Cronobacter infection, it is not known at what age or why these infants become less susceptible. Our study objectives were to compare the susceptibilities of neonatal mice of different ages to Cronobacter sakazakii infection. Timed-pregnant CD-1 mice were allowed to give birth naturally. Neonatal mice were orally gavaged at postnatal days (PNDs) 1.5, 5.5, and 9.5 with a single dose of vehicle or 10(3), 10(7), or 10(10) CFU/ml C. sakazakii strain MNW2 in reconstituted powdered infant formula. Pups were euthanized 7 days after challenge. Brains, livers, and ceca were excised and analyzed for C. sakazakii invasion, and blood was collected for serum amyloid A analysis as a biomarker of infection. C. sakazakii invasion was age dependent; the pathogen was isolated from brains, livers, and ceca of neonatal mice treated at PNDs 1.5 and 5.5 but not from those of pups treated at PND 9.5. C. sakazakii was more invasive at PND 1.5 in brains than in livers and ceca and was isolated from 22, 14, and 18% of these tissue samples, respectively. Serum amyloid A was detected in only one treated neonate. Mortality was observed only in neonates treated at PND 1.5. In conclusion, neonatal mice had a time-dependent susceptibility to C. sakazakii infection, with resistance increasing with increasing age. 相似文献
997.
Traditional detection methods for Enterobacteriaceae in foods are time-consuming and laborious. The current study assessed the specificity of three real-time PCR primer sets.
Set A (IEC primers) targeted the conserved flanking regions of the 16S rRNA, the 16S-ITS-23S gene region. Set B (ENT primers) annealed to Escherichia coli 16S ribosomal RNA gene. The third set (C) used a D-LUX™ (Light Upon eXtension) single FAM-labelled forward primer and a corresponding
unlabeled primer. Set A was specific for E. coli and for some non-Enterobacteriaceae. SYBR Green-based real-time PCR confirmed the specificity of set B for the Enterobacteriaceae
but also detected Vibrionaceae. In contrast, set C was poorly specific. However, set D including the forward LUX™ primer from
set C and the reverse primer from set B had a specificity comparable to that of set B, but with higher sensitivity. This combined
set was successfully applied to detect Enterobacteriaceae in infant milk formula and compared favourably with a commercial
real-time PCR kit. 相似文献
998.
This paper focuses on optimal design of block layouts when using more than one distance metric within a single facility. Previous work in block layout has assumed a single distance metric, usually the shortest rectilinear distance between department centroids, during the design step. However, most facilities have more than one method of material handling and alternative material handling systems can imply alternative distance metrics and cost structures. Specifically, up to three distance metrics within a single facility are considered--the shortest rectilinear distance between centroids (appropriate for automated guided vehicles and forklift trucks), the Tchebychev (maximum) distance (appropriate for overhead cranes) and the shortest Euclidean distance between centroids (appropriate for conveyor lines). Optimal block layouts using each of these distance metrics individually and then collectively are compared and contrasted. This approach can also be used to compare layouts when the choice of material handling system is not clear. It is argued that incorporating the distance metric that best reflects the planned material handling device is more realistic than previous formulations, avoids block layouts that are sub-optimal for the material handling systems installed, and is quite workable within a heuristic optimization framework. 相似文献
999.
Takashi Kodama Naoki Takahashi Shingo Matsuoka Mikio Kumagai Shin-itiro Hayashi 《Journal of Nuclear Science and Technology》2013,50(4):467-471
In case of the boiling and drying accident of a high-level liquid waste (HLLW) tank, a large amount of ruthenium (Ru) will be volatilized. In order to suppress the release of radioactive materials to the environment, the vapor may be led to the neighboring cells in which it will contact with the cell walls to be partially condensed. To understand the behavior of Ru in this situation, we have prepared an experimental apparatus. It consists of a small tank in which 60 mL simulated HLLW is heated to dryness, a 9.6 L stainless steel box which mimics the neighboring cell accepting the vapor from the small tank, and a condenser where the vapor coming out from the box is cooled to collect the condensate. The results show that more than 99% of the volatilized Ru is removed from the vapor in the box if its temperature is below about 120 °C. 相似文献
1000.
P Szymański A Lázničková M Lázniček M Bajda B Malawska M Markowicz E Mikiciuk-Olasik 《International journal of molecular sciences》2012,13(8):10067-10090
In the present study we describe the synthesis and biological assessment of new tacrine analogs in the course of inhibition of acetylcholinesterase. The obtained molecules were synthesized in a condensation reaction between activated 6-BOC-hydrazinopyridine-3-carboxylic acid and 8-aminoalkyl derivatives of 2,3-dihydro-1H-cyclopenta[b]quinoline. Activities of the newly synthesized compounds were estimated by means of Ellman's method. Compound 6h (IC(50) = 3.65 nM) was found to be most active. All obtained novel compounds present comparable activity to that of tacrine towards acetylcholinesterase (AChE) and, simultaneously, lower activity towards butyrylcholinesterase (BChE). Apart from 6a, all synthesized compounds are characterized by a higher affinity for AChE and a lower affinity for BChE in comparison with tacrine. Among all obtained molecules, compound 6h presented the highest selectivity towards inhibition of acetylcholinesterase. Molecular modeling showed that all compounds demonstrated a similar binding mode with AChE and interacted with catalytic and peripheral sites of AChE. Also, a biodistribution study of compound 6a radiolabeled with (99m)Tc was performed. 相似文献