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91.
Florenza Lüder Ripoli Annika Mohr Susanne Conradine Hammer Saskia Willenbrock Marion Hewicker-Trautwein Silvia Hennecke Hugo Murua Escobar Ingo Nolte 《International journal of molecular sciences》2016,17(5)
Mammary neoplasms are the tumors most affecting female dogs and women. Formalin-fixed, paraffin-embedded (FFPE) tissues are an invaluable source of archived biological material. Fresh frozen (FF) tissue is considered ideal for gene expression analysis. However, strategies based on FFPE material offer several advantages. Branched-DNA assays permit a reliable and fast workflow when analyzing gene expression. The aim of this study was to assess the comparability of the branched-DNA assay when analyzing certain gene expression patterns between FF and FFPE samples in canine mammary tumors. RNA was isolated from 109 FFPE samples and from 93 FF samples of different canine mammary tissues. Sixteen (16) target genes (Tp53; Myc; HMGA1; Pik3ca; Mcl1; MAPK3; FOXO3; PTEN; GATA4; PFDN5; HMGB1; MAPK1; BRCA2; BRCA1; HMGA2; and Her2) were analyzed via branched-DNA assay (b-DNA). ACTB, GAPDH, and HPRT1 were used as data normalizers. Overall, the relative gene expression of the two different origins of samples showed an agreement of 63%. Still, care should be taken, as FFPE specimens showed lower expression of the analyzed targets when compared to FF samples. The fact that the gene expression in FFPE proved to be lower than in FF specimens is likely to have been caused by the effect of storage time. ACTB had the best performance as a data normalizer. 相似文献
92.
DellaGreca M Isidori M Lavorgna M Monaco P Previtera L Zarrelli A 《Journal of chemical ecology》2004,30(4):867-879
Twenty-five 9,10-dihydrophenanthrenes, four phenanthrenes, a dihydrodibenzoxepin, and a pyrene, isolated from the wetland plant Juncus acutus, were tested to detect their effects on the green alga Selenastrum capricornutum. Nine of the compounds were isolated and identified for the first time. Most of the compounds caused inhibition of algal growth. The 9,10-dihydrophenanthrenes 1, 5, 21, and 22 were the most active. 相似文献
93.
Semiconducting polyurethane/polypyrrole/polyaniline for microorganism immobilization and wastewater treatment in anaerobic/aerobic sequential packed bed reactors 下载免费PDF全文
Iveth D. Antonio‐Carmona Silvia Y. Martínez‐Amador Hugo Martínez‐Gutiérrez Víctor M. Ovando‐Medina Omar González‐Ortega 《应用聚合物科学杂志》2015,132(28)
The development of new materials for microorganism immobilization is very important in wastewater treatment. In this work polyurethane (PU) foams were modified polymerizing pyrrole and aniline onto their surface by chemical oxidization to obtain polyurethane/polypyrrole (PU/PPy), polyurethane/polyaniline (PU/PANI), and PU/(PPy‐co‐PANI) supports which were used to immobilize microorganisms for municipal wastewater treatment in batch mode and continuous flow using two sequential (anaerobic/aerobic) packed bed reactors (PBR) varying the total hydraulic retention time (HRT). The supports were characterized by Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) and tested in chemical oxygen demand (COD) removal during treatment of a municipal wastewater. It was observed from SEM analysis that globular nanostructures of PPy and PPy‐co‐PANI were formed onto the PU surface with average diameters between 100 and 300 nm, which are typical of aqueous polymerization of pyrrole monomer; however irregular nanostructures were observed when PANI was homopolymerized onto the PU foam. Batch wastewater treatment after 14 days showed COD removal efficiencies of 77%, 69%, 78%, and 80% for PU foam, PU/PPy, PU/PANI, and PU/(PPy‐co‐PANI), respectively; which was explained as a function of polymers morphology deposited onto the PU foam surface. Also it was observed from the sequential PBR that for 24 h and 36 h of HRT, 80 and 90% of COD removal can be achieved; respectively.© 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42242. 相似文献
94.
Jacomijn Pluimers Carolien Kroeze Evert Jan Bakker Hugo Challa Leen Hordijk 《Nutrient Cycling in Agroecosystems》2001,60(1-3):209-218
In this paper, present-day emissions of greenhouse gases and acidifying compounds from agriculture are analysed at the farm level. Quantitative estimates are given for these emissions from three nested systems in the Netherlands: the agricultural sector, greenhouse horticulture, and tomato cultivation under glass. Total emissions are subdivided into emissions from biogenic sources and abiogenic sources. We conclude that, although most of the emissions from the agricultural sector have biogenic sources, those from abiogenic sources should not be neglected. Abiogenic emissions are mainly from greenhouse horticulture. The cost-effectiveness of options to reduce carbon dioxide (CO2) and nitrogen oxides (NOx) emissions from on-farm combustion of natural gas in tomato cultivation under glass is analysed. An inventory is given of technical reduction options that are presently available in practice. Based on information about the costs and the reduction potential of each option, cost-efficiency curves are derived for both types of emissions. Relative to a situation where none of the described options were applied (early nineties), CO2 and NOx emissions from tomato cultivation can be reduced at most by about 70% and 75%, respectively, by combinations of technical options. This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
95.
Carlos F. Torres Hugo S. Garcia Jason J. Ries Charles G. Hill Jr. 《Journal of the American Oil Chemists' Society》2001,78(11):1093-1098
Free fatty acids from fish oil were prepared by saponification of menhaden oil. The resulting mixture of fatty acids contained
ca. 15% eicosapentaenoic acid (EPA) and 10% docosahexaenoic acid (DHA), together with other saturated and monounsaturated fatty
acids. Four commercial lipases (PS from Pseudomonas cepacia, G from Penicillium camemberti, L2 from Candida antarctica fraction B, and L9 from Mucor miehei) were tested for their ability to catalyze the esterification of glycerol with a mixture of free fatty acids derived from
saponified menhaden oil, to which 20% (w/w) conjugated linoleic acid had been added. The mixtures were incubated at 40°C for
48h. The ultimate extent of the esterification reaction (60%) was similar for three of the four lipases studied. Lipase PS
produced triacylglycerols at the fastest rate. Lipase G differed from the other three lipases in terms of effecting a much
slower reaction rate. In addition, the rate of incorporation of omega-3 fatty acids when mediated by lipase G was slower than
the rates of incorporation of other fatty acids present in the reaction mixture. With respect to fatty acid specificities,
lipases PS and L9 showed appreciable discrimination against esterification of EPA and DHA, respectively, while lipase L2 exhibited
similar activity for all fatty acids present in the reaction mixture. The positional distribution of the various fatty acids
between the sn-1,3 and sn-2 positions on the glycerol backbone was also determined. 相似文献
96.
97.
98.
Bruna A Bregadiolli Hasina H Ramanitra Rodrigo Marques Ferreira Laura Corcoles Milton S Gomes Lauren Kang Craig MS Combe Hugo Santos Silva Francisco C Lavarda Didier Bégué Christine Dagron‐Lartigau Maria Luiza M Rocco Christine K Luscombe Clarissa A Olivati Carlos FO Graeff Roger C Hiorns 《Polymer International》2017,66(10):i-i
The cover image, by Bruna A. Bregadiolli et al., is based on the Research Article Towards the synthesis of poly(azafulleroid)s: main chain fullerene oligomers for organic photovoltaic devices, DOI: 10.1002/pi.5419 .
99.
Investigation of the collapse of bubbles after the impact of a piston on a liquid free surface 下载免费PDF全文
Maya Mounir Daou Elena Igualada Hugo Dutilleul Jean‐Marie Citerne Javier Rodríguez‐Rodríguez Stéphane Zaleski Daniel Fuster 《American Institute of Chemical Engineers》2017,63(6):2483-2495
A novel technique based on the impact of a piston on a liquid confined in a vessel is described. Pressure measurements reveal that strong pressure variations (up to 100 atmospheres) with a rich content of frequencies are efficiently transmitted to the liquid. High‐speed camera visualizations show that pre‐existing millimetric bubbles always collapse during the first instants of the impact whereas the behavior of submillimetric bubbles depends on the features of the pressure evolution in the system. In addition to the impact velocity, the amount of gas/vapor trapped between the piston and the liquid's surface plays an important role on how pressure evolves. Only when negative pressure occurs tiny bubbles grow significantly and collapse. The violent collapse of bubbles promote turbulence and mixing at very small length‐scales which renders this technique interesting to intensify processes limited by heat and mass diffusion. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2483–2495, 2017 相似文献
100.
Hugo Martínez‐Gutiérrez Víctor M. Ovando‐Medina René D. Peralta Eduardo Mendizábal Jorge E. Puig 《Polymer Engineering and Science》2013,53(9):1990-1995
Vinyl acetate (VAc) was polymerized by a seeded semicontinuous heterogeneous process. Stable latexes with a polymer/surfactant weight ratio of 65 were obtained, which is comparable with the highest value reported in the literature for emulsion polymerization but with the advantage of obtaining smaller particles (average diameter, Dp = 53 nm) which are similar to those obtained by microemulsion polymerization. The surfactant (sodium dodecylsulfate, SDS) concentration used in the recipe (0.32 wt%) is much lower than those typically used in microemulsion polymerization. Although molar masses increased during the continuous monomer addition period, they were small at the end of the reaction (Mn = 69 × 103 g·mol–1) and this was attributed to bimolecular termination inside the particles. The values of polymerization rate (Rp) and monomer addition rate (Fm) were nearly the same, indicating that polymerization was performed under monomer starved conditions. POLYM. ENG. SCI., 2013. © 2013 Society of Plastics Engineers 相似文献