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1.
Christoph Gottschalk Aiko Huckauf Arne Dübecke Florian Kaltner Matthias Zimmermann Ines Rahaus 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2018,35(7):1366-1383
The contamination of honey with hepatotoxic pyrrolizidine alkaloids (PAs) is a well-known hazard for food safety. While management strategies and controls of the honey industry aim to reduce the PA levels, uncertainties remain with regard to the safety of regionally produced and marketed honey. In addition, a previous study showed large differences of results obtained after various periods of storage and apparent differences between the analytical results of different laboratories. Therefore, this study aimed at examining these uncertainties by monitoring the impact of storage on the PA and PA N-oxide (PANO) content of two freshly harvested honeys and on possible demixing effects caused by pollen settling. Additionally, three analytical approaches – target analysis with matrix-matched calibration or standard addition and a sum parameter method – were applied for a comparative analysis of 20 honeys harvested in summer 2016. All samples originated from Schleswig-Holstein in Northern Germany where the PA plant Jacobaea vulgaris is currently observed on a massive scale. The results of the time series analyses showed that PANO levels markedly decreased within a few weeks and practically reached the LOD 16 weeks after harvest. Tertiary PAs, by contrast, remained stable and did not increase as a consequence of PANO decrease. The experiments on a putative demixing, which may result in a heterogeneous distribution of PAs/PANOs, revealed that there was no such effect during storage of up to 12 weeks. A comparison of the PA/PANO levels obtained by different analytical approaches showed that in some cases the sum parameter method yielded much higher levels than the target approaches, whereas in other cases, the target analysis with standard addition found higher levels than the other two methods. In summary, the results of this study highlight uncertainties regarding the validity and comparability of analytical results and consequently regarding health risk assessment. 相似文献
2.
Monique Jackson Ines Benkhemis Micka?l Begon Philippe Sardain Claude Vallée Patrick Lacouture 《Multibody System Dynamics》2012,28(3):225-237
Optimal synthesis of human movement or the prediction of the kinematics of a new movement require not only that the multi-body system be modeled but also that a performance criterion is specified. For sub-maximal movements the selection of a suitable performance criterion, able to generate realistic dynamic behavior is difficult. A two-dimensional simulation model of the take-off phase of a sub-maximal long jump was developed to study the effect of criterion choice on the realism of simulated movements. A parametric optimization technique was employed to obtain solutions to the constrained equations of motion. Seven different criteria were evaluated, by comparing simulated movements with an actual performance, to identify the criterion which most closely approximated that spontaneously minimized by the athlete. Synthesis of the take-off phase of a sub-maximal long jump was found to be sensitive to the chosen criterion, with a criterion based on minimizing joint intersegmental forces found to perform well. 相似文献
3.
Bourouis Sami Channoufi Ines Alroobaea Roobaea Rubaiee Saeed Andejany Murad Bouguila Nizar 《Multimedia Tools and Applications》2021,80(4):5809-5831
Multimedia Tools and Applications - This study presents an unsupervised novel algorithm for color image segmentation, object detection and tracking based on unsupervised learning step followed with... 相似文献
4.
Ines Hofinger Jörg Möller Manfred Bobeth Karen Raab 《Journal of Thermal Spray Technology》2002,11(3):387-392
The adherence of plasma sprayed NiCrAlY bond coats can be improved by an appropriate substrate surface finish. The interface
fracture energy for crack propagation along the coating/substrate interface has been measured for different surface roughness
by means of a specially designed four-point bending test. An increase of the interface fracture energy of about 15% was observed
for a three times higher surface roughness. In addition, four-point bending tests with the coating on the side face of bending
specimens were performed to analyze the fracture and spalling behavior of the coatings both under large tensile and compressive
substrate deformations. 相似文献
5.
In this paper we describe briefly a set of procedures for the optimal design of full mission aerospace systems. This involves multi-physics simulations at various fidelity levels, surrogates, distributed computing and multi-objective optimization. Low-fidelity analysis is used to populate a database of inputs and outputs of the system simulation and Neural Networks are then designed to generate inexpensive surrogates. Higher fidelity is used only where is warranted and also to do a local exploration after global optimization techniques have been used on the surrogates in order to provide plausible initial values. The ideas are exemplified on a generic supersonic aircraft configuration, where one of the main goals is to reduce the ground sonic boom. 相似文献
6.
Shuai Song Xiao-Na Song Nimisha Pathak Ines Tejado Balsera 《International Journal of Control, Automation and Systems》2017,15(4):1524-1535
In this work, we combine the active and adaptive control theories, and propose a novel synchronization scheme for a class of fractional-order chaotic systems with different structure and different order. Based on the new version of fractional-order Lyapunov stability theory, we design the adaptive controllers and updating laws of different switching. We use the fractional-order Lorenz chaotic system and the fractional-order Chen chaotic system as examples to analyze the multi-switching synchronization process for fractional-order chaotic systems with different structures and different orders. Finally, numerical simulations are also given to illustrate the effectiveness and validation of the proposed method, and the model uncertainties and external disturbances are added to the considered systems to verify the robustness of the proposed controllers. 相似文献
7.
Ines Maestro Laura R. de la Ballina Gracia Porras Silvia Corrochano Eva De Lago Anne Simonsen Patricia Boya Ana Martinez 《International journal of molecular sciences》2022,23(20)
Mitophagy is the selective degradation of mitochondria by autophagy. It promotes the turnover of mitochondria and prevents the accumulation of dysfunctional mitochondria, which can lead to cellular degeneration. Mitophagy is known to be altered in several pathological conditions, especially in neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS). We recently demonstrated an increase in autophagy flux in lymphoblasts from ALS patients bearing a mutation in SOD1. Thus, the identification of mitophagy inhibitors may be a therapeutic option to recover mitochondrial homeostasis. Here, using a phenotypic mitophagy assay, we identified a new mitophagy inhibitor, the small molecule named IGS2.7 from the MBC library. Interestingly, the treatment of different cellular and in vivo models of ALS with mutations on SOD1 and TARDBP with this inhibitor restores autophagy to control levels. These results point mitophagy inhibitors, especially IGS2.7, to a new therapeutic approach for familial ALS patients. 相似文献
8.
Petra Buri Ivana arapar Dijana Pavi
i-Hamer Ines Kova
i Lara Jurkovi Maja Dutour Sikiri Darija Domazet Jurain Nevenka Mikac Niko Ba
i Daniel Mark Lyons 《International journal of molecular sciences》2023,24(1)
Silver nanoparticles represent a threat to biota and have been shown to cause harm through a number of mechanisms, using a wide range of bioassay endpoints. While nanoparticle concentration has been primarily considered, comparison of studies that have used differently sized nanoparticles indicate that nanoparticle diameter may be an important factor that impacts negative outcomes. In considering this, the aim of the present study was to determine if different sizes of silver nanoparticles (AgNPs; 10, 20, 40, 60 and 100 nm) give rise to similar effects during embryogenesis of Mediterranean sea urchins Arbacia lixula and Paracentrotus lividus, or if nanoparticle size is a parameter that can modulate embryotoxicity and spermiotoxicity in these species. Fertilised embryos were exposed to a range of AgNP concentrations (1–1000 µg L−1) and after 48 h larvae were scored. Embryos exposed to 1 and 10 µg L−1 AgNPs (for all tested sizes) showed no negative effect in both sea urchins. The smaller AgNPs (size 10 and 20 nm) caused a decrease in the percentage of normally developed A. lixula larvae at concentrations ≥50 µg L−1 (EC50: 49 and 75 μg L−1, respectively) and at ≥100 µg L−1 (EC50: 67 and 91 μg L−1, respectively) for P. lividus. AgNPs of 40 nm diameter was less harmful in both species ((EC50: 322 and 486 μg L−1, for P. lividus and A. lixula, respectively)). The largest AgNPs (60 and 100 nm) showed a dose-dependent response, with little effect at lower concentrations, while more than 50% of larvae were developmentally delayed at the highest tested concentrations of 500 and 1000 µg L−1 (EC50(100 nm); 662 and 529 μg L−1, for P. lividus and A. lixula, respectively. While AgNPs showed no effect on the fertilisation success of treated sperm, an increase in offspring developmental defects and arrested development was observed in A. lixula larvae for 10 nm AgNPs at concentrations ≥50 μg L−1, and for 20 and 40 nm AgNPs at concentrations >100 μg L−1. Overall, toxicity was mostly ascribed to more rapid oxidative dissolution of smaller nanoparticles, although, in cases, Ag+ ion concentrations alone could not explain high toxicity, indicating a nanoparticle-size effect. 相似文献
9.
Ines Thabti Walid Elfalleh Manel Ziadi Maria Graça Campos Ali Ferchichi 《International Journal of Food Properties》2013,16(4):842-854
Leaves and stem bark composition from Morus species (M. alba var. alba, M. alba var. rosa and M. rubra) was evaluated for its antioxidant and antimicrobial activities in order to enhance its therapeutic uses. Total phenolics and flavonoids contents were estimated in hydromethanolic and aqueous extracts. Results showed highest content in M. rubra leaves aqueous extract (1129 mg gallic acid equivalent/100 g dry weight and 816 mg gallic acid equivalent/100 g dry weight, respectively). Using 2,2-diphenyl-1-picrylhydrazyl assay, the highest antioxidant activity was obtained in aqueous stem barks extracts. M. alba var. alba has an IC50 of 2.84 mg/ml and the IC50 value of M. rubra was the highest (4.78 mg/ml). ABTS.+ (2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) method and reducing power assay were used to confirm the results from the 2,2-diphenyl-1-picrylhydrazyl test. All extracts expressed considerable free radical-scavenging properties. Hydromethanolic and aqueous extracts were tested against Staphylococcus aureus, Enterococcus feacalis, Staphylococcus epidermis, Escherichia coli, and Salmonella Typhimurium bacteria. Hydromethanolic stem bark extracts have the highest antimicrobial activities, and it may be a good antimicrobial agent for human gastrointestinal infections. This plant could be used as an additive to foods and also as a possible source to obtain new and effective herbal medicines to treat infections of multi-drug resistant strains of microorganisms. 相似文献
10.
Qi Zhou Tijana Perovic Ines Fechner Lowell T. Edgar Peter R. Hoskins Holger Gerhardt Timm Krüger Miguel O. Bernabeu 《Journal of the Royal Society Interface》2021,18(179)
Sprouting angiogenesis is an essential vascularization mechanism consisting of sprouting and remodelling. The remodelling phase is driven by rearrangements of endothelial cells (ECs) within the post-sprouting vascular plexus. Prior work has uncovered how ECs polarize and migrate in response to flow-induced wall shear stress (WSS). However, the question of how the presence of erythrocytes (widely known as red blood cells (RBCs)) and their impact on haemodynamics affect vascular remodelling remains unanswered. Here, we devise a computational framework to model cellular blood flow in developmental mouse retina. We demonstrate a previously unreported highly heterogeneous distribution of RBCs in primitive vasculature. Furthermore, we report a strong association between vessel regression and RBC hypoperfusion, and identify plasma skimming as the driving mechanism. Live imaging in a developmental zebrafish model confirms this association. Taken together, our results indicate that RBC dynamics are fundamental to establishing the regional WSS differences driving vascular remodelling via their ability to modulate effective viscosity. 相似文献