139 research outputs found
Analyse des langages et modèles de la mobilité
Ce document présente une analyse comparative de divers langages prototypes et modèles formels existants pour la mobilité de code. Trois aspects sont retenus pour cette étude: la distribution, la mobilité, et la sécurité. L'étude est également structurée autour de la notion de domaine qui nous semble centrale dans ces langages et modèles, et illustre différentes sémantiques de cette notion
Bifurcation à AgroParisTech : quelle voie pour une formation résolument interdisciplinaire ?
The adult boar testicular and epididymal transcriptomes
<p>Abstract</p> <p>Background</p> <p>Mammalians gamete production takes place in the testis but when they exit this organ, although spermatozoa have acquired a specialized and distinct morphology, they are immotile and infertile. It is only after their travel in the epididymis that sperm gain their motility and fertility. Epididymis is a crescent shaped organ adjacent to the testis that can be divided in three gross morphological regions, head (caput), body (corpus) and tail (cauda). It contains a long and unique convoluted tubule connected to the testis via the efferent ducts and finished by joining the <it>vas deferens </it>in its caudal part.</p> <p>Results</p> <p>In this study, the testis, the efferent ducts (<it>vas efferens</it>, VE), nine distinct successive epididymal segments and the deferent duct (<it>vas deferens</it>, VD) of four adult boars of known fertility were isolated and their mRNA extracted. The gene expression of each of these samples was analyzed using a pig generic 9 K nylon microarray (AGENAE program; GEO accession number: GPL3729) spotted with 8931 clones derived from normalized cDNA banks from different pig tissues including testis and epididymis. Differentially expressed transcripts were obtained with moderated t-tests and F-tests and two data clustering algorithms based either on partitioning around medoid (top down PAM) or hierarchical clustering (bottom up HCL) were combined for class discovery and gene expression analysis. Tissue clustering defined seven transcriptomic units: testis, <it>vas efferens </it>and five epididymal transcriptomic units. Meanwhile transcripts formed only four clusters related to the tissues. We have then used a specific statistical method to sort out genes specifically over-expressed (markers) in testis, VE or in each of the five transcriptomic units of the epididymis (including VD). The specific regional expression of some of these genes was further validated by PCR and Q-PCR. We also searched for specific pathways and functions using available gene ontology information.</p> <p>Conclusion</p> <p>This study described for the first time the complete transcriptomes of the testis, the epididymis, the <it>vas efferens </it>and the <it>vas deferens </it>on the same species. It described new genes or genes not yet reported over-expressed in these boar tissues, as well as new control mechanisms. It emphasizes and fulfilled the gap between studies done in rodents and human, and provides tools that will be useful for further studies on the biochemical processes responsible for the formation and maintain of the epididymal regionalization and the development of a fertile spermatozoa.</p
Identification of ageing biomarkers in human dermis biopsies by thermal analysis (DSC) combined with Fourier transform infrared spectroscopy (FTIR/ATR)
Background/purpose : The purpose of this clinical study was to identify suitable biomarkers for a better understanding of the molecular and organizational changes in human dermis during intrinsic and extrinsic ageing. Methods : Sun-exposed and non-exposed skin biopsies were collected from twenty-eight women devised in two groups (20-30 and ≥60 years old). The hydric organization and thermal transitions were determined by Differential Scanning Calorimetry (DSC). Fourier Transform Infrared spectroscopy (FTIR) was used to identify the absorption bands of the dermis and to quantify the different absorbance ratio. Results : The amounts of total, freezable and unfreezable water were determined. A significant increasing amount of freezable water is evidenced in sun-exposed area skin of aged group compared with young group (P=.0126). Another significant effect of extrinsic ageing (P=.0489) is the drastic decrease of fibrillary collagen, the main protein component of dermis. The only significant effect of intrinsic ageing (P=.0184) is an increase of the heat-stable fraction of collagens in dermis. Conclusion : DSC and FTIR are well-suited techniques to characterize human skin, giving accurate results with a high reproducibility. The combination of these techniques is useful for a better understanding of human skin modifications with intrinsic and extrinsic ageing
Flash gas chromatography electronic nose as a potential tool for rapid sensory screening of virgin olive oils
Alignment and Proficiency of Virgin Olive Oil Sensory Panels: The OLEUM Approach
A set of 334 commercial virgin olive oil (VOO) samples were evaluated by six sensory panels during the H2020 OLEUM project. Sensory data were elaborated with two main objectives: (i) to classify and characterize samples in order to use them for possible correlations with physical\u2013chemical data and (ii) to monitor and improve the performance of panels. After revision of the IOC guidelines in 2018, this work represents the first published attempt to verify some of the recommended quality control tools to increase harmonization among panels. Specifically, a new \u201cdecision tree\u201d scheme was developed, and some IOC quality control procedures were applied. The adoption of these tools allowed for reliable classification of 289 of 334 VOOs; for the remaining 45, misalignments
between panels of first (on the category, 21 cases) or second type (on the main perceived defect,
24 cases) occurred. In these cases, a \u201cformative reassessment\u201d was necessary. At the end, 329 of
334 VOOs (98.5%) were classified, thus confirming the eectiveness of this approach to achieve
a better proficiency. The panels showed good performance, but the need to adopt new reference
materials that are stable and reproducible to improve the panel\u2019s skills and agreement also emerged
Olive oil quality and authenticity: A review of current EU legislation, standards, relevant methods of analyses, their drawbacks and recommendations for the future
Background: The physical, chemical and organoleptic characteristics of olive oil (OO) are regulated by the
European Union (EU) by Reg. (EEC) 2568/91 as amended, which also establishes methods for their analysis.
Despite the fact that the OO sector is highly regulated, it is acknowledged that there are still problems; fats
and oils, including OOs, are ranked third, after meat and meat products and fish and fish products, in the 2016
EU Food Fraud report on non-compliances per product category.
For this reason, EU legislation, among the most advanced in the field, continuously chases after the emerging
frauds. The process of proposing new methods or reviewing those current is constantly in progress, to ensure the
robustness and the clarity required by official standardised procedures.
Scope and approach: This review will identify current gaps in EU legislation and discuss drawbacks of existing
analytical methods with respect to OO. Suggestions for replacement of specific steps within the present EU
methods with more efficient analytical solutions to reduce time and/or solvent consumption will be proposed.
Key findings and conclusions: This review critiques existing regulatory methods and standards, highlights
weaknesses and proposes possible solutions to safeguard the consumer and protect the OO market
Chain dynamics of human dermis by Thermostimulated currents: a tool for new markers of aging
Abstract Background/purpose: The purpose of this clinical study was to identify dielectric markers to complete a previous thermal and vibrational study on the molecular and organizational changes in human dermis during intrinsic and extrinsic aging. Methods: Sun-exposed and non-exposed skin biopsies were collected from 28 women devised in two groups (20-30 and ≥60 years old). The dielectric relaxation modes associated with localized and delocalized dynamics in the fresh and dehydrated state were determined by the Thermostimulated currents technique (TSC). Results: Intrinsic and extrinsic aging induced significant evolution of some of the dielectric parameters of localized and delocalized dynamics of human skin. With photo-aging, freezable water forms a segregated phase in dermis and its dynamics is close to free water, what evidences the major role of extrinsic aging on water organization in human skin. Moreover, TSC indicators highlight the restriction of localized mobility with intrinsic aging due to glycation, and the cumulative effect of chronological aging and photo-exposition on the molecular mobility of the main structural proteins of the dermis at the mesoscopic scale. Conclusion: TSC is a well-suited technique to scan the molecular mobility of human skin. It can be uses as a relevant complement of vibrational and thermal characterization to follow human skin modifications with intrinsic and extrinsic aging
Collaborative peer validation of a harmonized SPME-GC-MS method for analysis of selected volatile compounds in virgin olive oils [intervalidazione di un metodo armonizzato SPME-GC-MS per lÂżanalisi di composti volatili selezionati in oli di oliva vergini]
Final version is available in open access in publisher’s site.-- This abstract is based on the published article: RamĂłn Aparicio-Ruiz, Clemente Ortiz Romero, Enrico Casadei, Diego L. GarcĂa-González, Maurizio Servili, Roberto Selvaggini, Florence Lacoste, Julien Escobessa, Stefania Vichi, Beatriz Quintanilla-Casas, Pierre-Alain Golay, Paolo Lucci, Erica Moret, Enrico Valli, Alessandra Bendini, Tullia Gallina Toschi. Collaborative peer validation of a harmonized SPME-GC-MS method for analysis of selected volatile compounds in virgin olive oils, Food Control, Volume 135, 2022, 108756, https://doi.org/10.1016/j.foodcont.2021.108756.-- http://hdl.handle.net/10261/258960The evaluation of the sensory attributes in virgin olive oil (VOO) is carried out according to the standard
method of panel test [1, 2]. Recently, it has been proposed as SPME-GC-FID method as the most ade-
quate instrumental method to determine volatiles compounds in VOO to support the sensory panels test
[3]. This method developed in the European funded project OLEUM, in which all the variables have been
defined and harmonized, has been tested in three laboratories to perform an inter-laboratory validation of
the quantification of the most relevant VOCs that are responsible for VOO sensory attributes. The valida-
tion study was carried out for each one of the selected molecules in order to have an individual infor-
mation for each analyte. With the same objective, in the present work, five laboratories, all being active
partners in the OLEUM project, carried out an inter-lab evaluation of the SPME-GC-MS joint protocol.
The validation was carried out by each laboratory following the same analytical conditions and on the
same samples, in order to make the results obtained by each laboratory comparable in a harmonized
procedure and methodology, as previously done with FID [3]
Olive oil quality and authenticity: a review of current EU legislation, standards, relevant methods of analyses, their drawbacks and recommendations for the future
Final version is available in open access in publisher’s site.-- This abstract is based on the published article Lanfranco Conte, Alessandra Bendini, Enrico Valli, Paolo Lucci, Sabrina Moret, Alain Maquet, Florence Lacoste, Paul Brereton, Diego Luis GarcĂa-González, Wenceslao Moreda, Tullia Gallina Toschi, Olive oil quality and authenticity: A review of current EU legislation, standards, relevant methods of analyses, their drawbacks and recommendations for the future, Trends in Food Science & Technology, Volume 105, 2020,
Pages 483-493, https://doi.org/10.1016/j.tifs.2019.02.025.-- http://hdl.handle.net/10261/198878Peer reviewe
- …