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21.
Platelet lysate and adipose mesenchymal stromal cells on silk fibroin nonwoven mats for wound healing 下载免费PDF全文
Chlapanidas Theodora Perteghella Sara Faragò Silvio Boschi Alessandra Tripodo Giuseppe Vigani Barbara Crivelli Barbara Renzi Sabrina Dotti Silvia Preda Stefania Marazzi Mario Torre Maria Luisa Ferrari Maura 《应用聚合物科学杂志》2016,133(5)
In this work platelet lysate (PL) and adipose‐derived mesenchymal stromal cells (ASCs) seeded on nonwoven fibroin mats were in vitro and in vivo evaluated for tissue regenerative applications. Nonwoven mats obtained by a large scale water entanglement technique were characterized for their physico‐chemical properties. Results indicated a high purity of fibroin fibers, their stability after sterilization process and appropriate technological properties suitable for tissue engineering. Moreover, the scaffolds in vitro supported adhesion and migration of ASCs and the presence of PL improved the cell proliferation. The products were then applied on epithelial/dermal wounds carried out on the dorsal surface of rabbit: the skin reparative process was solved in 9 days, with a completely restitutio ad integrum of the epithelium in animals treated with PL alone; ASCs did not further improve the wound healing. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42942. 相似文献
22.
Miguel A. Lpez Manchado Jerrico Blagiotti Luigi Torre Jos M. Kenny 《Polymer Engineering and Science》2000,40(10):2194-2204
The effects of the incorporation of different types of fibers on the crystallization kinetics and thermodynamics of isotactic polypropylene (iPP) are investigated. The study is mainly performed by thermal analysis, both in isothermal and constant cooling rate conditions, utilizing differential scanning calorimetry (DSC). The crystallization kinetics of the studied composites is successfully described by the Avrami model. Moreover, the effects of different kind of fibers are studied comparing the values of kinetics parameters such as the Avrami exponent n, the kinetic constant of the crystallization rate, Kn and the half‐time of crystallization, T 1/2. The results of the investigation show that the fibers behave as effective nucleant agents for the crystallization of polypropylene. In fact, a dramatic decrease of the half‐time of crystallization, T1/2, as well as a sensible increase of the overall crystallization rate, Kn, are observed in the presence of all the fibers analyzed. These effects are more marked in the presence of aramid fibers. The Avrami model is successfully applied to describe the crystallization kinetics of the composites. The kinetic curves obtained under non‐isothermal conditions confirm the results obtained under isothermal conditions and demonstrate the nucleating action of the fibers on the PP crystallization. Furthermore, the spherulite growth and the transcrystallinity on the surface of the fibers are investigated by optical polarizing microscopy. It is observed that transcrystallinity takes place in all kind of fibers studied, but also in this case, aramid fibers are the most effective in promoting transcrystallinity. 相似文献
23.
Ackermann T. Ancell G. Borup L.D. Eriksen P.B. Ernst B. Groome F. Lange M. Mohrlen C. Orths A.G. O'Sullivan J. de la Torre M. 《Power and Energy Magazine, IEEE》2009,7(6):65-75
The power systems in Denmark, Spain, Ireland, and New Zealand have some of the highest wind penetrations in the world (see Table 1). The management of the different power systems to date, with increasing amounts of wind energy, has been successful. There have been no incidents in which the wind has directly or indirectly been a major factor causing operational problems for the system. However, there are a number of parameters that are being monitored that indicate the need for active management in the near future (and in some cases already today). In this article, we briefly describe the situations in these four countries, giving special emphasis to the market integration of wind power, the use of wind forecasting, and curtailment experience. The final section provides an overview of the main wind forecasting methodologies and challenges. 相似文献
24.
F. Arena T. Torre A. Venuto F. Frusteri A. Mezzapica A. Paraliana 《Catalysis Letters》2002,80(1-2):69-72
A preparation method of highly effective methane to formaldehyde partial oxidation (MPO) FeOx/SiO2 catalysts (Fe 0.09--0.43 wt%) is reported, based on adsorption-precipitation (ADS/PRC) of FeII ions under controlled conditions. The performance of ADS/PRC catalysts in the MPO reaction at 650 °C has been compared with that of conventional systems prepared by incipient wetness (INC/WET) of silica carriers with aqueous solutions of FeIII. The ADS/PRC method, likely enabling a higher dispersion of the active phase, provides very effective MPO catalysts featuring CH4 turnover frequency (TOF) and HCHO productivity (STYHCHO) values larger than those of the counterpart INC/WET systems. 相似文献
25.
Miriam Amo Fernando Martínez Margarita Torre 《IEEE transactions on image processing》2006,15(5):1192-1201
In this paper, we present a user-guided method based on the region competition algorithm to extract roads, and therefore we also provide some clues concerning the placement of the points required by the algorithm. The initial points are analyzed in order to find out whether it is necessary to add more initial points, and this process will be based on image information. Not only is the algorithm able to obtain the road centerline, but it also recovers the road sides. An initial simple model is deformed by using region growing techniques to obtain a rough road approximation. This model will be refined by region competition. The result of this approach is that it delivers the simplest output vector information, fully recovering the road details as they are on the image, without performing any kind of symbolization. Therefore, we tried to refine a general road model by using a reliable method to detect transitions between regions. This method is proposed in order to obtain information for feeding large-scale Geographic Information System. 相似文献
26.
Growth of Bacillus cereus on solid media as affected by agar, sodium chloride, and potassium sorbate
The effect of two independent variables: microstructure, as modified by the agar content (1.0, 4.0, 7.0%), and water activity (a(w)), as modified by the NaCl content (0.5, 2.5, 4.5%), in the absence or in the presence of potassium sorbate (0.0; 2,000 ppm) on Bacillus cereus growth on solid media was studied. The time to visible growth (TVG) and the radial growth rate (RGR) of colonies were evaluated. TVG was not affected by microstructure and K-sorbate, although when a(w) was reduced, TVG tended to increase. RGR depended on linear effects of microstructure and a(w) variables and their interaction. When K-sorbate was added to cultural media, RGR was reduced significantly. However, in the presence of K-sorbate, RGR was found to change only when a(w) vas varied. 相似文献
27.
Giovanna Loredana La Torre Marcello SaittaFortunato Vilasi Teresa PellicanòGiacomo Dugo 《Food chemistry》2006
Phenolic compounds in Sicilian wines were directly detected using an HPLC with a PDA detector coupled on-line with a MS system equipped with Electrospray Ionisation (ESI) source operated in the negative-ion mode and a quadrupole mass analyzer. In this work, MS spectra were recorded at different voltage, to obtain structural elucidations in addition to molecular mass informations. The different response of the compounds identified has been also evaluated. MS characteristics of cis- and trans-piceid were determined on the basis of the response obtained with the ESI interface. 相似文献
28.
D Torre G Ferrario M Issi A Pugliese F Speranza 《Canadian Metallurgical Quarterly》1996,49(9):733-736
AIMS: To evaluate the expression of the alpha 5 beta 1 integrin fibronectin receptor (FNR), which mediates several processes, including phagocytosis, cell motility and the immune response, on T lymphocytes of patients with HIV-1 infection. METHODS: T lymphocytes were incubated with monoclonal antibody directed against FNR and then with monoclonal antibodies, conjugated with phycoerythrin, directed against CD3, CD4 and CD8 positive cells. Expression of FNR on CD3, CD4 and CD8 positive cells was analysed using flow cytometry. RESULTS: Normal expression of FNR was observed on CD3 positive cells from asymptomatic HIV positive patients and those with AIDS. Increased expression of FNR was observed on CD8 positive cells from asymptomatic HIV positive patients and on CD4 positive cells from patients with AIDS. Increased FNR expression was observed on CD4 positive cells from patients with AIDS, particularly those with opportunistic infections caused by Pneumocystis carinii, Mycobacterium sp, Toxoplasma gondii, and Cryptococcus neoformans. CONCLUSION: Increased expression of FNR on CD8 and CD4 positive cells in asymptomatic HIV positive patients and those with AIDS, respectively, may be an epiphenomenon correlated with lymphocyte activation by HIV-1 or opportunistic infection, Further study is required to determine whether upregulation of FNR expression has a direct role in the pathogenesis of AIDS. 相似文献
29.
An inhomogeneous applied field can cause an instability in a strip domain that can be used for the controlled generation of bubble domains. These instabilities have been studied experimentally and theoretically by means of a variational calculation. Good agreement is obtained between wall shape calculations and experimental data. Predictions of cutting current as a function of strip width deviate, however, for widths larger than ∼5.5h due to the limitations of the model and the experimental conditions. 相似文献
30.