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排序方式: 共有222条查询结果,搜索用时 0 毫秒
1.
Molecular structure and granule morphology of native and heat‐moisture‐treated pinhão starch 下载免费PDF全文
Vania Z. Pinto Khalid Moomand Nathan L. Vanier Rosana Colussi Franciene A. Villanova Elessandra R. Zavareze Loong‐Tak Lim Alvaro R. G. Dias 《International Journal of Food Science & Technology》2015,50(2):282-289
Pinhão seed is an unconventional source of starch and the pines grow up in native forests of southern Latin America. In this study, pinhão starch was adjusted at 15, 20 and 25% moisture content and heated to 100, 110 and 120 °C for 1 h. A decrease in λ max (starch/iodine complex) was observed as a result of increase in temperature and moisture content of HMT. The ratio of crystalline to amorphous phase in pinhão starch was determined via Fourier transform infra red by taking 1045/1022 band ratio. A decrease in crystallinity occurred as a result of HMT. Polarised light microscopy indicated a loss of birefringence of starch granules under 120 °C at 25% moisture content. Granule size distribution was further confirmed via scanning electron microscopy which showed the HMT effects. These results increased the understanding on molecular and structural properties of HMT pinhão starch and broadened its food and nonfood industrial applications. 相似文献
2.
This work investigates the regeneration of S-poisoned Pd/Al2O3 and Pd/CeO2/Al2O3 catalysts under different CH4 containing atmospheres. Under lean combustion conditions in the presence of excess O2, partial regeneration took place for both systems only above 750 °C after decomposition of stable sulphate species adsorbed
on the support. Under alternate lean combustion/CH4-reducing pulse regeneration is markedly anticipated down to 550–600 °C. Experiments evidenced an effective role of ceria
in preventing PdO from sulphation and in promoting regeneration via sulphates decomposition under reducing conditions. 相似文献
3.
Mónica Giménez‐Marqués Elena Bellido Thomas Berthelot Teresa Simón‐Yarza Tania Hidalgo Rosana Simón‐Vázquez África González‐Fernández José Avila Maria Carmen Asensio Ruxandra Gref Patrick Couvreur Christian Serre Patricia Horcajada 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(40)
Controlling the outer surface of nanometric metal–organic frameworks (nanoMOFs) and further understanding the in vivo effect of the coated material are crucial for the convenient biomedical applications of MOFs. However, in most studies, the surface modification protocol is often associated with significant toxicity and/or lack of selectivity. As an alternative, how the highly selective and general grafting GraftFast method leads, through a green and simple process, to the successful attachment of multifunctional biopolymers (polyethylene glycol (PEG) and hyaluronic acid) on the external surface of nanoMOFs is reported. In particular, effectively PEGylated iron trimesate MIL‐100(Fe) nanoparticles (NPs) exhibit suitable grafting stability and superior chemical and colloidal stability in different biofluids, while conserving full porosity and allowing the adsorption of bioactive molecules (cosmetic and antitumor agents). Furthermore, the nature of the MOF–PEG interaction is deeply investigated using high‐resolution soft X‐ray spectroscopy. Finally, a cell penetration study using the radio‐labeled antitumor agent gemcitabine monophosphate (3H‐GMP)‐loaded MIL‐100(Fe)@PEG NPs shows reduced macrophage phagocytosis, confirming a significant in vitro PEG furtiveness. 相似文献
4.
Rosana A. DiasAuthor Vitae Edmond CretuAuthor VitaeReinoud WolffenbuttelAuthor Vitae Luis A. RochaAuthor Vitae 《Sensors and actuators. A, Physical》2011,172(1):47-53
The pull-in time (tpi) of electrostatically actuated parallel-plate microstructures enables the realization of a high-sensitivity accelerometer that uses time measurement as the transduction mechanism. The key feature is the existence of a metastable region that dominates pull-in behavior, thus making pull-in time very sensitive to external accelerations. Parallel-plate MEMS structures have been designed and fabricated using a SOI micromachining process (SOIMUMPS) for the implementation of the accelerometer. This paper presents the experimental characterization of the microdevices, validating the concept and the analytical models used. The accelerometer has a measured sensitivity of 0.25 μs/μg and a bandwidth that is directly related to the pull-in time, BW = 1/2tpi ≈ 50 Hz. These specifications place this sensor between the state of the art accelerometers found both in the literature and commercially. More importantly, the resolution of the measurement method used is very high, making the mechanical-thermal noise the only factor limiting the resolution. The in-depth noise analysis to the system supports these conclusions. The total measured noise floor of 400 μg (100 μs) is mainly due to the contribution of the environmental noise, due to lack of isolation of the experimental setup from the building vibrations (estimated mechanical thermal noise of 2.8 μg/√Hz). The low requirements of the electronic readout circuit makes this an interesting approach for high-resolution accelerometers. 相似文献
5.
Colussi C Banfi C Brioschi M Tremoli E Straino S Spallotta F Mai A Rotili D Capogrossi MC Gaetano C 《Proteomics. Clinical applications》2010,4(1):71-83
Purpose: Histone Deacetylase Inhibitors (DI) ameliorates dystrophic muscle regeneration restoring muscular strength in the mdx mouse model of Duchenne muscular dystrophy (DMD). The further development of these compounds as drugs for DMD treatment is currently hampered by the lack of knowledge about DIs effect in large dystrophic animal models and that of suitable biomarkers to monitor their efficacy. Experimental design: In this study we applied proteomic analysis to identify differentially expressed proteins present in plasma samples from mdx mice treated with the Suberoylanilide hydroxamic acid (SAHA) and relative normal controls (WT). Results: Several differentially expressed proteins were identified between untreated wild type and mdx mice. Among these, fibrinogen, epidermal growth factor 2 receptor, major urinary protein and glutathione peroxidase 3 (GPX3) were constitutively up‐regulated in mdx, while complement C3, complement C6, gelsolin, leukaemia inhibitory factor receptor (LIFr), and alpha 2 macroglobulin were down‐regulated compared to WT mice. SAHA determined the normalization of LIFr and GPX3 protein level while apoliprotein E was de novo up‐regulated in comparison to vehicle‐treated mdx mice. Conclusions and clinical relevance: Collectively, these data unravel potential serological disease biomarkers of mdx that could be useful to monitor muscular dystrophy response to DI treatment. 相似文献
6.
Sacha inchi (Plukenetia volubilis L.) shell: an alternative source of phenolic compounds and antioxidants 下载免费PDF全文
Rosana Chirinos Ornella Necochea Romina Pedreschi David Campos 《International Journal of Food Science & Technology》2016,51(4):986-993
Sacha inchi seed (SI) is known as a rich source of oil with high content of polyunsaturared fatty acids of the ω‐3 and ω‐6 type (~85% of total fatty acids). However, few studies have focused on the use of by‐products from the seed. The aim of this study was to characterise the main phenolic families present in SI shell and to evaluate the best extraction solvent for the extraction of phenolic compounds (PC) and antioxidant capacity (AOXC). The PC content corresponded to 74.5 ± 5.1 mg g?1 of which 93.1% were condensed tannins and the remaining compounds corresponded to free and bound phenolic acids, hydrolyzable tannins, flavonoids and flavanoids. Protocatechic and p‐coumaric acids but also hydroxycinammic acid derivatives of ferulic and o‐coumaric type and lignan derivatives were identified. Acetone containing solvents favoured the extraction of higher amounts of total PC and AOXC. This study highlights the potential use of SI shell as a novel and alternative source of PC antioxidants for the nutraceutical and/or functional food industries. 相似文献
7.
Gleber Tacio Teixeira Rosana Ftima Teixeira Lomba Agatha Densy dos Santos Francisco Joo Francisco Cajaíba da Silva Regina Sandra Veiga Nascimento 《应用聚合物科学杂志》2014,131(12)
To prevent the degradation of the borehole and also the disintegration and dispersion of drilled cuttings, different shale stabilizing additives are used in water‐based drilling fluids (WBFs). Glycols, poly(ethylene glycol), glycerols, and polyglycerol derivatives, also called polyols, have been used to inhibit shales containing reactive clays in WBF. These additives are normally used in conjunction with KCl to reduce clay swelling and dispersion of drilled cuttings. Highly branched polymers have become an important field in current polymer science. Such materials typically exhibit compact, globular structures in combination with an exceptionally high number of sites with functional groups. They have unique properties that differ significantly from their linear counterparts, and the hyperbranched polyglycerol (hPG) is an important hyperbranched polymer that can be produced from an environmentally benign monomer, the glycerol carbonate. In this article, the clay inhibitive properties of hPG were evaluated by different test methods including bentonite inhibition test, cuttings recovery, and X‐ray diffraction measurements. The results show that the hPG has a great potential to be used as an environmental friendly inhibitor additive in WBFs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40384. 相似文献
8.
Dr. Patricia García‐Domínguez Mélanie Weiss Ilaria Lepore Prof. Dr. Rosana Álvarez Prof. Dr. Lucia Altucci Prof. Dr. Hinrich Gronemeyer Prof. Dr. Ángel R. de Lera 《ChemMedChem》2012,7(12):2101-2112
A novel epigenetic modulator that displays a DNMT1 inhibition and DNMT3A activation profile was characterized (compound 8 ). This compound is a derivative of palmitic acid that incorporates the putative reactive functional group (diynone) of the peyssonenyne natural products. Other analogues containing the diynone or an acetoxyenediyne did not show the same biological profile. In U937 human leukemia cells, diynone 8 induced cell differentiation and apoptosis, which correlated with the expression of Fas protein. Very surprisingly, diynone 8 was toxic to normal human fibroblasts (BJ) and mouse embryo fibroblasts (MEF), but not to immortalized human fibroblasts (BJEL); this unique effect was not observed with the classical DNMT inhibitor 5‐azacytidine. Therefore, compound 8 interferes in a very specific manner with signaling pathways, the activities of which differ between normal and immortalized cell types. This toxicity is reminiscent of the effects of Dnmt1 ablation on mouse fibroblasts. In fact, some of the genes deregulated by the loss of Dnmt1 are similarly deregulated by 8 , but not by the DNMT inhibitor SGI‐1027. 相似文献
9.
Elizandra Silva da Penha Rogrio Lacerda‐Santos Luanna Abílio Diniz Melquíades de Medeiros Rosana Araújo Rosendo Antonielson dos Santos Marcus Vinícius Lia Fook Wladymyr Jefferson Bacalhau de Sousa Millena de Oliveira Firmino Erik Montagna 《Microscopy research and technique》2020,83(10):1208-1216
The focus of this triple‐blind study was on evaluating the effect of chitosan combined with Dysphania ambrosioides (A) extract on the bone repair process in vivo. In total, 60 male Wistar rats (Rattus norvegicus albinus) weighing between 260 and 270 g were randomly selected for this study and distributed into four groups (n = 15). Group C (chitosan), Group CA5 (chitosan + 5% of D. ambrosioides), Group CA20 (chitosan + 20% of D. ambrosioides), and Group CO (Control‐Blood clot). In each animal, bone defects measuring 2 mm in diameter were performed in both tibias for placement of the substances. After 7, 15, and 30 days, the animals were sedated and sacrificed using the cervical dislocation technique and the tissues were analyzed under optical microscope relative to the following events: inflammatory infiltrate, necrosis, osteoclasts, osteoblasts, fibroblasts, periosteal, and endosteal bone formation. The data were evaluated to verify distribution using the Kolmogorov–Smirnov test, and variance, using the Levene test; as distribution was not normal, data were subjected to the Kruskal–Wallis and Dunn nonparametric tests (p < .05). A significant inflammatory infiltrate was observed in Group CA5 (p = .008) in the time interval of 7 days, and in Group C at 15 (p = .009) and 30 (p = .017) days. Osteoblastic activity was more significant in Group CA20 (p = .027) compared with CA5 in the time interval of 7 days. Group CA20 demonstrated a significantly higher endosteal and periosteal bone formation value in the time interval of 7 (p = .013), 15 (p = .004), and 30 days (p = .008) compared with the other groups. The null hypothesis was refuted, bone regeneration was faster in spheres with an association of chitosan and 20% extract, and complete bone repair occurred clinically at 15 days and histologically at 30 days. The spheres proved to be a promising method for the biostimulation of alveolar bone repair and bone fractures. 相似文献