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排序方式: 共有660条查询结果,搜索用时 15 毫秒
71.
Angela Salzano Francesca Licitra Nunzia DOnofrio Maria Luisa Balestrieri Antonio Limone Giuseppe Campanile Michael J. DOcchio Gianluca Neglia 《Journal of dairy science》2019,102(9):7717-7722
The aim of the present study was to determine if space allocation influenced the concentration of biomolecules in buffalo milk and dairy products. Intensively housed buffaloes (n = 96) were randomly assigned to 2 groups according to days in milk, parity, and milk yield: group S10 had a space allocation of 10 m2 per buffalo and group S15 had a space allocation of 15 m2 per buffalo. Individual milk yield was recorded daily. Twice a month, a bulk milk sample was collected for each group, as well as whey, ricotta, and mozzarella cheese, to assess cheese yield and to conduct HPLC-electrospray ionization-tandem mass spectrometry, milk antioxidant activity, and cell viability analyses. We tested milk extracts from the 2 groups in vitro to evaluate their efficacy in counteracting endothelial oxidative damage induced by high glucose. We evaluated reproductive function in 28 buffaloes from each group using the Ovsynch-timed artificial insemination program. We observed no differences in milk quantity or quality in terms of fat, protein, or lactose, and reproductive function did not differ between the 2 groups. Compared with group S10, group S15 had higher concentrations of carnitine (56.7 ± 1.1 vs. 39.8 ± 0.7 mg/L in milk and 40.9 ± 0.8 vs. 31.7 ± 0.7 mg/L in whey), acetyl-l-carnitine (51.9 ± 0.3 vs. 39.7 ± 0.7 mg/L in milk and 41.1 ± 1.7 vs. 28.7 ± 2.6 mg/L in whey), propionyl-l-carnitine (34.8 ± 1.0 vs. 21.0 ± 0.9 mg/L in milk and 26.9 ± 0.8 vs. 17.6 ± 1.2 mg/L in whey), glycine betaine (23.1 ± 1.9 vs. 13.5 ± 1.6 mg/L in milk and 10.7 ± 0.4 vs. 7.9 ± 0.5 mg/L in whey), and δ-valerobetaine (24.2 ± 0.5 vs. 16.7 ± 0.5 mg/L in milk and 22.0 ± 0.9 vs. 15.5 ± 0.7 mg/L in whey). Group S15 also had higher total antioxidant activity than group S10 (56.7 ± 1.9 vs. 46.4 ± 1.13 mM Trolox equivalents). Co-incubation of high-glucose-treated endothelial cells with milk extracts from group S15 improved cell viability compared with cells treated with high glucose only; it also reduced intracellular lipid peroxidation (144.3 ± 0.4 vs. 177.5 ± 1.9%), reactive oxygen species (141.3 ± 0.9 vs. 189.3 ± 4.7 optical density units), and cytokine release (tumor necrosis factor-α, IL-1β, IL-6). Greater space allocation was associated with higher levels of biomolecules in buffalo milk. This could have been the result of improved welfare in buffaloes that were allocated more space. 相似文献
72.
Carmela De Simone Pasquale Ferranti Gianluca Picariello Ilaria Scognamiglio Alessandra Dicitore Francesco Addeo Lina Chianese Paola Stiuso 《Molecular nutrition & food research》2011,55(2):229-238
Scope: Milk proteins are a source of bioactive peptides. Recent studies have indicated that protein‐derived peptides released in buffalo cheese acid whey exert a cytomodulatory effect in human epithelial colon cancer (CaCo2) cells. The aim of the present study was to explain the molecular mechanism involved in the response of CaCo2 cells to oxidative stress in the presence of peptide fractions of buffalo cheese whey, purified and characterized by mass spectrometry. Methods and results: We demonstrated that treatment of CaCo2 treated with H2O2 (H‐CaCo2) cells with a partially purified peptide sub‐fraction (f3) from buffalo cheese acid whey induced a reduction of mitochondrial superoxide anion with subsequent decrease in heat shock protein 70 and 90 expression. Moreover, we observed a 5‐fold decrease in cyclin A expression and cell cycle arrest in G1/G0 phases. These responses were associated with increased activity of alkaline phosphatase and beta‐galactosidase, markers of differentiation and senescence respectively. Conclusions: The structural characterization of the active peptide fraction and the elucidation of the effects induced by its treatment on H‐CaCo2 cells in vitro demonstrated an activity of this peptide sub‐fraction in the modulation of cell cycle, thus suggesting potential application for the development of nutraceuticals as well as health‐promoting functional foods. 相似文献
73.
Bocciarelli Massimiliano Ranzi Gianluca 《Structural and Multidisciplinary Optimization》2020,61(1):91-110
Structural and Multidisciplinary Optimization - Hygro-thermo-chemical-mechanical models, used to determine the variations over time of temperature, relative humidity and shrinkage induced... 相似文献
74.
Miguel Pallares Davide Fascione Gianluca Iannotta Alessandro Laner Alessandro Leanti Enrico Pellegrini Jenny Spagnolatti Santiago Trujillo Anna Zauli Andrea Martiradonna 《世界建筑导报》2018,(5)
正Piuarch建筑师事务所负责设计了2015年米兰世博会埃内尔(意大利国家电力公司)展馆及卡里塔斯展馆。为了将客户想表达的含义与价值观更好地传达给观众,Piuarch选择了一种特殊的建筑语言来体现两个展馆的特点。埃内尔展馆沿东西大街而建,占地900平方米。设计体现出智能电网这一概念,传达出以智能科技优化世博会整体用电的理念。 相似文献
75.
76.
Francesco Centurelli Pietro Monsurrò Vincenzo Stornelli Gianluca Barile Alessandro Trifiletti 《International Journal of Circuit Theory and Applications》2020,48(4):472-484
A 4th-order Butterworth class-AB current-mode low-pass filter is proposed, based on second-generation Current Conveyors (CCII). Class-AB operation allows high-power efficiency and driving large loads with small quiescent currents. The CCII topology uses the class-AB output buffer with error amplifiers: this topology is known to be sensitive to mismatch errors, which cause offsets in the error amplifiers, affecting the biasing current of the stage. This problem is solved via a control loop, which compensates the effect of mismatches. The technique is shown to be effective in Monte Carlo simulations with process variations and mismatches. Simulations have been carried out in 40 nm CMOS technology. The proposed filter achieves good power efficiency, thanks to the class-AB architecture, and good dynamic range, thanks to the closed-loop output buffer. A cut-off frequency of 6 MHz, with 184 μW of total quiescent power consumption, is achieved, with a THD of -55 dB and a SNR of 49 dB. 相似文献
77.
Donatella Restuccia Gianluca Giorgi Umile Gianfranco Spizzirri Fabio Sciubba Giorgio Capuani Vittoria Rago Gabriele Carullo Francesca Aiello 《International Journal of Food Science & Technology》2019,54(4):1313-1320
Seeds and skins from grape pomaces of Pecorello and Mantonico cv underwent extraction (ultrasound–assisted or maceration), in order to obtain added-value ingredients for the production of a functional pear jam. The antioxidant features of the extracts were tested by in vitro colorimetric assays. Among seeds, Mantonico by maceration (MSC) showed the best results, as well as Mantonico by ultrasound-assisted extraction (MBs) among skin extracts. The selected extracts were fully characterised by NMR and MS techniques, confirming the presence of many polyphenols, flavonoids and tannins among others. Pectin was then derivatised by the grafting procedure with the active molecules of MBs and MSC. The latter produced the best antioxidant polymer also without toxicity evaluated using Caco-2 cells and was used for the jam preparation. The functional pear jam showed improved antioxidant performances in comparison with its non-functional counterparts as well as its maintenance over time (15 days). 相似文献
78.
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80.
One major concern since the development of the field ion microscope is the mechanical strength of the specimens. The macroscopic shape of the imaging tip greatly influences field-induced stresses and there is merit in further study of this phenomenon from a classical perspective. Understanding the geometrical, as opposed to localized electronic, factors that affect the stress might improve the quality and success rate of atom probe experiments. This study uses macroscopic electrostatic principles and finite element modelling to investigate field-induced stresses in relation to the shape of the tip. Three two-dimensional idealized models are considered, namely hyperbolic, parabolic and sphere-on-orthogonal-cone; the shapes of which are compared to experimental tips prepared by electro-polishing. Three dimensional morphologies of both a nano-porous and single-crystal aluminium tip are measured using electron tomography to quantitatively test the assumption of cylindrical symmetry for electro-polished tips. The porous tip was prepared and studied to demonstrate a fragile specimen for which such finite element studies could determine potential mechanical failure, prior to any exhaustive atom probe investigation. 相似文献