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61.
Philippe Szternfeld Svetlana V. Malysheva Vincent Hanot Laure Joly 《Food Analytical Methods》2016,9(5):1173-1179
Glyphosate determination in liver is challenging due to this particular molecule/matrix combination. Glyphosate is a very polar molecule and liver composition is highly variable between individuals and species. Since 2014, the Multiannual Control Program (MACP) of the European Union (EU) demands to analyse glyphosate in food of animal origin on a voluntary basis. Moreover, this analysis will be mandatory in 2017. This paper describes a robust and easily transferable method for glyphosate quantification in liver of animal origin by means of liquid chromatography–tandem mass spectrometry (LC-MS/MS). An intensive clean-up was used to eliminate matrix interferences and was combined with a derivatization step which ensures good retention of glyphosate on a conventional reverse-phase LC column. This method allows to meet the MACP requirements without a time-consuming change in the set-up of the routinely used LC-MS/MS system. Furthermore, it allows the use of an LC column and mobile phases often used in multi-residue analysis. The analytical method was validated according to the SANCO/12571/2013 criteria. Isotopic dilution was used to quantify glyphosate, leading to mean apparent recoveries of 115 and 101 % for the low (0.025 mg kg?1) and the high (0.250 mg kg?1) fortification levels, respectively. At both levels, the relative standard deviation was below 10 %. The limit of quantification of 0.025 mg kg?1 was found to be satisfactory as it was below the maximum residue level (MRL) value set at 0.050 mg kg?1 for glyphosate in liver. It is also the lowest MRL for all commodity types. 相似文献
62.
Y. Leterrier A. Mottet N. Bouquet D. Gilliéron P. Dumont A. Pinyol L. Lalande J.H. Waller J.-A.E. Månson 《Thin solid films》2010,519(5):1729-1737
The interplay between residual stress state, cohesive and adhesive properties of coatings on substrates is reviewed in this article. Attention is paid to thin inorganic coatings on polymers, characterized by a very high hygro-thermo-mechanical contrast between the brittle and stiff coating and the compliant and soft substrate. An approach to determine the intrinsic, thermal and hygroscopic contributions to the coating residual stress is detailed. The critical strain for coating failure, coating toughness and coating/substrate interface shear strength are derived from the analysis of progressive coating cracking under strain. Electro-fragmentation and electro-fatigue tests in situ in a microscope are described. These methods enable reproducing the thermo-mechanical loads present during processing and service life, hence identifying and modeling the critical conditions for failure. Several case studies relevant to food and pharmaceutical packaging, flexible electronics and thin film photovoltaic devices are discussed to illustrate the benefits and limits of the present methods and models. 相似文献
63.
Wigginton KR Menin L Sigstam T Gannon G Cascella M Hamidane HB Tsybin YO Waridel P Kohn T 《Chembiochem : a European journal of chemical biology》2012,13(6):837-845
Much research has been dedicated to understanding the molecular basis of UV damage to biomolecules, yet many questions remain regarding the specific pathways involved. Here we describe a genome-mediated mechanism that causes site-specific virus protein cleavage upon UV irradiation. Bacteriophage MS2 was disinfected with 254 nm UV, and protein damage was characterized with ESI- and MALDI-based FT-ICR, Orbitrap, and TOF mass spectroscopy. Top-down mass spectrometry of the products identified the backbone cleavage site as Cys46-Ser47 in the virus capsid protein, a location of viral genome-protein interaction. The presence of viral RNA was essential to inducing backbone cleavage. The similar bacteriophage GA did not exhibit site-specific protein cleavage. Based on the major protein fragments identified by accurate mass analysis, a cleavage mechanism is proposed by radical formation. The mechanism involves initial oxidation of the Cys46 side chain followed by hydrogen atom abstraction from Ser47 C(α). Computational protein QM/MM studies confirmed the initial steps of the radical mechanism. Collectively, this study describes a rare incidence of genome-induced protein cleavage without the addition of sensitizers. 相似文献
64.
This paper, which is based on the detailed analysis of the post-war archives of the French Christian union Confédération Fran?aise des Travailleurs Chrétiens (CFTC), which became the Confédération Fran?aise Démocratique du Travail (CFDT) in 1964, highlights the difficulties, both from a practical and ideological point of view, for a militant organisation to embrace the cause of immigrant workers and to give them a voice. The CFDT had to ‘construct’ immigrant workers as a group they could represent, which means as a group that relates to French workers, despite possible xenophobia. A key moment was the denunciation of their housing conditions that make immigrant workers not competitors in the job market but victims of injustice. The union had to reinvent its engagement frames in order to include the specific problems faced by the immigrant workforce. The study shows that the urban dimension was essential in this process as Paris slums made visible an important plight of migrants and provided the opportunity to change public opinion. 相似文献
65.
Xi Wang Xinqiang Cao Laure Bourgeois Hasigaowa Guan Shimou Chen Yeteng Zhong Dai‐Ming Tang Huiqiao Li Tianyou Zhai Liang Li Yoshio Bando Dmitri Golberg 《Advanced functional materials》2012,22(13):2682-2690
A new facile route to fabricate N‐doped graphene‐SnO2 sandwich papers is developed. The 7,7,8,8‐tetracyanoquinodimethane anion (TCNQ?) plays a key role for the formation of such structures as it acts as both the nitrogen source and complexing agent. If used in lithium‐ion batteries (LIBs), the material exhibits a large capacity, high rate capability, and excellent cycling stability. The superior electrochemical performance of this novel material is the result from its unique features: excellent electronic conductivity related to the sandwich structure, short transportation length for both lithium ions and electrons, and elastomeric space to accommodate volume changes upon Li insertion/extraction. 相似文献
66.
67.
The emergence of nanotechnology has coincided with an increased recognition of the need for new approaches to understand and manage the impact of emerging technologies on the environment and human health. Important elements in these new approaches include life-cycle thinking, public participation and adaptive management of the risks associated with emerging technologies and new materials. However, there is a clear need to develop a framework for linking research on the risks associated with nanotechnology to the decision-making needs of manufacturers, regulators, consumers and other stakeholder groups. Given the very high uncertainties associated with nanomaterials and their impact on the environment and human health, research resources should be directed towards creating the knowledge that is most meaningful to these groups. Here, we present a model (based on multi-criteria decision analysis and a value of information approach) for prioritizing research strategies in a way that is responsive to the recommendations of recent reports on the management of the risk and impact of nanomaterials on the environment and human health. 相似文献
68.
69.
A 90° microstrip bend is characterized using a time-frequency method based on the finite-difference-time-domain (FDTD) method. Time evolution of the currents generated by FDTD are Fourier transformed to lead to S-parameters and the radiated powers characteristic of the microstrip bend. The method for calculating both radiation and surface wave losses is developed for microstrip structures. The results of the 90° microstrip bend are compared with the results of the mitered microstrip bend 相似文献
70.
Beatrice Paillassa Benoît Escrig Riadh Dhaou Marie‐Laure Boucheret Caroline Bes 《International Journal of Satellite Communications and Networking》2011,29(6):479-500
This paper proposes new transmission schemes for the delivery of satellite services. In the proposed scenarios, mobile terminals are allowed to forward the signal received from the satellite. This scheme provides spatial diversity just like MIMO transmission schemes. Moreover, the coverage area is extended because masked terminals have an additional opportunity to get the service from neighboring terminals. We use the paradigm of cooperative communications to compare the advantages and limitations of several scenarios in hybrid terrestrial/satellite systems. In particular, we study the following basic transmission scheme: in a first time slot, the satellite sends its signal and, in a second time slot, mobile terrestrial terminals are relaying the satellite signal. An analysis framework is proposed and applied to this cooperation scenario at the destination terminal. The framework is modeling the cooperation process and clearly separates the control part from the data user part. The paper outlines the importance of the control part by evaluating the relay selection policy on a basic hybrid satellite/ad hoc system. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献