Working times in atypical forms of employment: the special case of part-time work

Chapitre 5, à la suite de la conférence ACSEG 2001 à RennesIn the present article, we attempt to devise a typology of forms of part-time employment by applying a widely used neuronal methodology called Kohonen maps. Starting out with data that we describe using category-specific variables, we show how it is possible to represent observations and the modalities of the variables that define them simultaneously, on a single map. This allows us to ascertain, and to try to describe, the main categories of part-time employment

Polyphenolic content and pharmacological potential of french BFA propolis extracts

Propolis, or bee glue, is a natural resinous hive product collected by honeybees from buds and exudates of various trees and plants. Mixed with beewax and salivary enzymes, it is employed to fill cracks and embalm dead invaders in the hive. Propolis has been used in folk medecine since ancien times due to its pharmacological potential associated with antioxidant, antifungal, antibacterial as well as antitumoral properties. A batch of various French propolis extracts, supplied by “Ballot-Flurin Apiculteurs” (BFA), a company located in the South-West of France and specialized in apitherapy products, was fractionated and analysed by HPLC/MS. Its qualitative chemical composition highlights the presence of polyphenols such as hydroxycinnamic acid derivatives and flavonoids. Total polyphenol content and antioxidant activities were evaluated on six BFA propolis extracts, using respectively Folin-Ciocalteu, DPPH and ORAC assays. Preliminary antifungal (Candida albicans) and antibacterial (Staphylococcus aureus) evaluations will also be given

Chemical composition, antioxidant and anti-AGEs activities of a French propolis

Accumulation in tissues and serum of advanced glycation end-products (AGEs) plays an important role in pathologies such as Alzheimer\u27s disease or, in the event of complications of diabetes, atherosclerosis or renal failure. Therefore there is a potential therapeutic interest in natural antioxidants with true anti-AGEs capabilities for the prevention of this kind of pathologies. The aim of this study was to evaluate the antioxidant and anti-AGEs potential of a French propolis batch (natural resinous substance collected by honeybees from differents plants and trees), then to identify the main compounds responsible for this anti-AGEs effect. For this purpose, the phytochemical composition of a 70% ethanolic extract of propolis (EEP70) was determined, using HPLC/DAD/MS and/or 1H and 13C NMR (1D and 2D) analysis. This study showed the presence of phenolic acids and their esters as well as flavonoids. Then, the evaluation of the antioxidant, using DPPH and ORAC assays, and the anti-AGEs potential, using an automated test recently developed in our laboratory, showed that EEP70 exhibited both high antioxidant (1650 ± 149 µmol TE/g) and anti-AGEs (IC50=0.03 mg/ml) activities. A bio-guided fractionation allowed us to identify the most active anti-AGEs compounds: pinobanksin-3-acetate (IC50=0.06 mM) which is the major compound of EEP70. Thus, EEP70 represents a good candidate as food additive to prevent glycoxidation. Boisard S, Le Ray A-M, Gatto J, Aumond M-C, Blanchard P, Derbré S, Flurin C, Richomme P: Chemical Composition, Antioxidant and Anti-AGEs Activities of a French Poplar Type Propolis. J Agric Food Chem 2014, 62:1344–1351

Matrix-free laser desorption ionization mass spectrometry as a functional tool for the analysis and differentiation of complex phenolic mixtures in propolis: a new approach to quality control

Matrix-free laser desorption ionization (LDI) is a rapid and versatile technique for the ionization of small, UV-light-absorbing molecules. Indeed, many natural products such as polyphenols exhibit inherent LDI properties, potentially facilitating their detection from highly complex samples such as crude extracts. With this in mind, the present work thoroughly evaluated the potential of LDI as an analytical tool for the chemical profiling and differentiation of propolis samples obtained from different global regions. Propolis is a complex bee product containing, among others, significant amounts of phenolic constituents that may show LDI effects. The present work will demonstrate that LDI not only provides reproducible and highly specific fingerprint spectra for each of the tested samples, it further allows their clear differentiation by principal compound analysis (PCA). Contrary to classical analytical approaches such as LC- or GC-MS, LDI does not require time-consuming sample preparation and method optimization procedures. Thus, the technique represents a most interesting analytical tool and potent supplement to classic LC-MS for quality control of herbal pharmaceuticals and dietary supplements. Present results clearly support this approach and further suggest the use of LDI as a versatile tool for the automated analysis of large sample batches on an industrial scale

Re-inventing artisanal knowledge and practice: a critical review of innovation in a craft-based industry

This paper presents a critical review of the ways in which the specialised knowledge and working practices of craft-based industries have been transformed in the context of broader processes of industrialisation and global competition. The opening section makes the case for artisanal knowledge as a ‘Cinderella’ subject that remains important yet largely uncharted territory for innovation researchers. It is followed by a critical review of existing empirical and theoretical studies that have examined the reproduction and reinvention of artisanal knowledge. The review concludes that valuable insights remain obscured due to the way in which this literature is distributed across discrete disciplines with little evidence of cross-fertilisation or integration. Several common themes emerge, which provide the basis for an outline theoretical framework. The central arguments are illustrated with reference to a case-based analysis of the technological and social innovations that have taken place in English farmhouse cheesemaking over an extended period, from the pre-industrial era to the beginning of the present century. The concluding section considers how more nuanced understandings of artisanal knowledge and practice might enhance innovation theory and contribute to the continued flourishing of craft-based industries

In vitro interactions of squash and wheat phytochrome with multilamellar liposomes

National audienc