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81.
María Murillo-Arbizu Susana Amézqueta Elena González-Peñas Adela López de Cerain 《Food chemistry》2009
A survey was conducted to determine levels and dietary intake of Patulin (PAT) from apple juices consumed in Spain. One hundred samples of apple juice were bought from distinct supermarkets. PAT was extracted by a liquid–liquid extraction technique and analysed with a micellar electrokinetic chromatography (MEKC) method. 66% of the samples contained PAT over the limit of detection of the method (0.7 μg L−1). The PAT apple juice mean and median levels obtained were 19.4 and 4.8 μg L−1, respectively, in a range between 0.7 and 118.7 μg L−1. In 11% of the samples, PAT contamination exceeded the maximum permitted level of 50 μg L−1 established by the EU regulation. In Spain, no significant variations were observed with respect to data published 15 years ago. 相似文献
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83.
Frantisek Jaluvka Peter Ihnat Juraj Madaric Adela Vrtkova Jaroslav Janosek Vaclav Prochazka 《International journal of molecular sciences》2020,21(23)
(1) Background: The treatment of peripheral arterial disease (PAD) is focused on improving perfusion and oxygenation in the affected limb. Standard revascularization methods include bypass surgery, endovascular interventional procedures, or hybrid revascularization. Cell-based therapy can be an alternative strategy for patients with no-option critical limb ischemia who are not eligible for endovascular or surgical procedures. (2) Aims: The aim of this narrative review was to provide an up-to-date critical overview of the knowledge and evidence-based medicine data on the position of cell therapy in the treatment of PAD. The current evidence on the cell-based therapy is summarized and future perspectives outlined, emphasizing the potential of exosomal cell-free approaches in patients with critical limb ischemia. (3) Methods: Cochrane and PubMed databases were searched for keywords “critical limb ischemia and cell therapy”. In total, 589 papers were identified, 11 of which were reviews and 11 were meta-analyses. These were used as the primary source of information, using cross-referencing for identification of additional papers. (4) Results: Meta-analyses focusing on cell therapy in PAD treatment confirm significantly greater odds of limb salvage in the first year after the cell therapy administration. Reported odds ratio estimates of preventing amputation being mostly in the region 1.6–3, although with a prolonged observation period, it seems that the odds ratio can grow even further. The odds of wound healing were at least two times higher when compared with the standard conservative therapy. Secondary endpoints of the available meta-analyses are also included in this review. Improvement of perfusion and oxygenation parameters in the affected limb, pain regression, and claudication interval prolongation are discussed. (5) Conclusions: The available evidence-based medicine data show that this technique is safe, associated with minimum complications or adverse events, and effective. 相似文献
84.
T.L. Mitran Adela Nicolaev G.A. Nemnes L. Ion S. Antohe 《Computational Materials Science》2011,50(10):2955-2959
The vibrational and thermal properties of small diameter AlN nanowires are investigated using first principles calculations. Upon applying external pressure, the nanowires suffer a stress induced phase transition from a würtzite (WZ) to a graphite-like (GL) phase. The thermal conductance displays a nearly identical behavior for all systems in the temperature regime governed by acoustical modes, while at higher temperatures the conductance is systematically enhanced for nanowires in the GL phase. The heat capacity points out the different phonon group velocities for the acoustical modes in the two structural configurations. Our DFT-based calculations are consistent with experimental data for bulk AlN, in terms of phonon spectrum and temperature dependent heat capacity in the large nanowire limit. 相似文献
85.
Adela M. Mao 《Information & Communications Technology Law》2014,23(2):136-158
As a matter of case law, the US courts would apportion the share of the copyright equally among co-authors, after a finding of co-authorship. The federal Copyright Act 1976 was the first legislative effort to statutorily provide for the doctrine of co-authorship in the US jurisprudence. However the 1976 Act neither clarifies the nature of co-authorship or how to apportion the shares, nor does legislative literature help. Courts are left with the task of clarification. Section 2 draws out two possible rationales behind the apportionment rule (the Equal Division Rule) and explores the difficulties. Section 3 proposes two alternatives (the Proportionate Rule) to the current apportionment rule based on the Default Theory analysis. For both works comprising quantifiable inseparable contributions and works comprising quantifiable interdependent contributions, the Penalty Default Theory favors the Proportionate Rule over the Equal Division Rule. Section 4 explores the interaction between the theories for co-authorship and the proposed alternative Proportionate Rule, and concludes that if the apportionment rule were instead devised to avoid the over-rewarding issue, as is the proposed Proportionate Rule, the courts would better conform to the statute and stick to a uniform test for co-authorship. Section 5 summarizes. 相似文献
86.
87.
Levine Susan C.; Huttenlocher Janellen; Taylor Amy; Langrock Adela 《Canadian Metallurgical Quarterly》1999,35(4):940
This study investigated sex differences in young children's spatial skill. The authors developed a spatial transformation task, which showed a substantial male advantage by age 4 years 6 months. The size of this advantage was no more robust for rotation items than for translation items. This finding contrasts with studies of older children and adults, which report that sex differences are largest on mental rotation tasks. Comparable performance of boys and girls on a vocabulary task indicated that the male advantage on the spatial task was not attributable to an overall intellectual advantage of boys in the sample. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
In this paper a new computerised approach to the accurate determination of thermal degradation of 1-ethyl-3-methylimidazolium ethylsulfate ionic liquid is considered. In this approach, an integrated neural network (NN)/thermogravimetric analyser (TGA) is designed to filter a noisy signal from TGA equipment. Data collected (sample weight loss as a function of sample temperature) from the TGA equipment were transferred into a NN trained computer for modeling and filtering of output. Such an integrated NN/TGA filter is capable to filter the noisy TGA output signal based on the created models and patterns, without any previous phenomenological knowledge. The NN/TGA equipment is able to filter the output of the experimental process with mean error less than 0.3%. 相似文献
89.
Adela Bernabeu-Zornoza Raquel Coronel Charlotte Palmer Victoria Lpez-Alonso Isabel Liste 《International journal of molecular sciences》2021,22(17)
Amyloid-β 42 peptide (Aβ1-42 (Aβ42)) is well-known for its involvement in the development of Alzheimer’s disease (AD). Aβ42 accumulates and aggregates in fibers that precipitate in the form of plaques in the brain causing toxicity; however, like other forms of Aβ peptide, the role of these peptides remains unclear. Here we analyze and compare the effects of oligomeric and fibrillary Aβ42 peptide on the biology (cell death, proliferative rate, and cell fate specification) of differentiating human neural stem cells (hNS1 cell line). By using the hNS1 cells we found that, at high concentrations, oligomeric and fibrillary Aβ42 peptides provoke apoptotic cellular death and damage of DNA in these cells, but Aβ42 fibrils have the strongest effect. The data also show that both oligomeric and fibrillar Aβ42 peptides decrease cellular proliferation but Aβ42 oligomers have the greatest effect. Finally, both, oligomers and fibrils favor gliogenesis and neurogenesis in hNS1 cells, although, in this case, the effect is more prominent in oligomers. All together the findings of this study may contribute to a better understanding of the molecular mechanisms involved in the pathology of AD and to the development of human neural stem cell-based therapies for AD treatment. 相似文献
90.
Peña-Farfal C Moreda-Piñeiro A Bermejo-Barrera A Bermejo-Barrera P Pinochet-Cancino H de Gregori-Henríquez I 《Analytical chemistry》2004,76(13):3541-3547
Ultrasound energy has been applied to speed up enzymatic hydrolysis processes of mussel tissue in order to determine trace and ultratrace elements (As, Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn). The element releases, by action of three proteases (pepsin, pancreatin, trypsin), lipase, and alpha-amylase, have been evaluated by inductively coupled plasma atomic emission spectrometry. Different variables such as pH, sonication temperature, ionic strength, hydrolysis time, ultrasound frequency, extracting volume, and enzyme mass were simultaneously studied by applying an experimental design approach (Plackett-Burman design and central composite design). Results showed that the hydrolysis time was statistically nonsignificant (confidence interval of 95%) for most of the elements and enzymes, meaning that the hydrolysis procedure can be finished within a 30-60-min range. These hydrolysis times are far shorter than those obtained when using thermostatic cameras, between 12 and 24 h. Statistically significant factors were the ultrasound frequency (the highest metals releasing at high-ultrasound frequency), pH, sonication temperature, and ionic strength. All metals can be extracted using the same operating conditions (pH of 1.0 and sodium chloride at 1.0% for pepsin; pH of 7.5, temperature at 37 degrees C, and 0.4 M potassium dihydrogen phosphate/potassium hydrogen phosphate buffer for amylase; pH of 8.0 and 0.5 M potassium dihydrogen phosphate/potassium hydrogen phosphate buffer for pancreatin; pH of 5.0 and 0.5 M potassium dihydrogen phosphate/potassium hydrogen phosphate buffer for lipase; pH of 8.0 and 0.2 M potassium dihydrogen phosphate/potassium hydrogen phosphate buffer for trypsin). Analytical performances, such as limits of detection and quantification, repeatability of the overall procedure, and accuracy, by analyzing DORM-1, DORM-2, and TORT-1 certified reference materials, were finally assessed for each enzyme. 相似文献