La participation syndicale des travailleurs dans un contexte de précarité de l’emploi

La précarité en emploi, qui peut se définir comme une accumulation d'insécurités ou comme un manque de protections dans sa relation d'emploi, est un phénomène toujours présent malgré des évolutions au fil du temps. La précarité peut revêtir de nombreuses formes : bas salaire, manque de contrôle de ses horaires de travail, contrat à durée déterminée, nombre d'heures insuffisant, manque d'accès à des éléments de protection sociale, manque d'accès aux dispositifs de représentation collective. Les nombreuses formes par lesquelles la précarité peut se manifester vont avoir un impact sur les conditions d'existence des individus, que ce soit par des privations matérielles (logement inadéquat, vêtements, nourriture, loisirs), du stress ou des effets sur la santé. En parallèle, les syndicats s'organisent et se battent pour garantir à leurs membres les meilleures conditions de travail possible. Dans le cas des travailleurs précaires, les syndicats militent pour de meilleurs droits, afin de contrer les effets négatifs induits par la précarité. Dans cette optique, la participation des membres à la vie de leur syndicat est vue comme primordiale : seuls ces derniers peuvent faire remonter au syndicat les problèmes présents dans leur milieu de travail et mettre en place des moyens de pression efficaces afin d'instaurer un rapport de force avec la direction de l’entreprise. D'un point de vue théorique, les modèles explicatifs de la participation syndicale des membres se basent en grande majorité sur une main-d'œuvre dite « traditionnelle », exempte de facteurs de précarité. L'objectif de notre recherche est donc d'appliquer une grille d'analyse de la participation des membres à la vie de leur syndicat en dehors des périodes de négociation, initialement prévue pour une main-d'œuvre « traditionnelle », à des collectifs de travail présentant des éléments de précarité. De par l'analyse de conditions de travail, des stratégies mises en place par le syndicat, ainsi que de la nature et l'intensité de la participation des membres, nous voyons en quoi la participation des travailleurs précaires à leur vie syndicale se distingue de celle de leurs homologues aux conditions d’emploi plus favorables. Pour ce faire, nous avons procédé à l'analyse et la comparaison de deux unités d'accréditation. Ces deux unités sont sous la même bannière syndicale, appartiennent au même groupe, officient dans des domaines économiques similaires et présentent des conditions de travail également similaires. Malgré cela, on remarque que l'intensité et la nature de la participation syndicale entre les deux groupes varient grandement. Notre analyse a donc consisté à rencontrer les acteurs syndicaux impliqués dans les deux cas : conseillers syndicaux, délégués syndicaux et président de la section locale. En nous appuyant sur les résultats de ces entrevues, nous avons mis en lumière les éléments de stratégie syndicale qui permettent à un groupe de présenter plus de participation que l'autre. Nous revenons ensuite sur les grandes théories concernant la participation syndicale des travailleurs aux conditions de travail classiques afin de voir quels éléments peuvent être étendus aux travailleurs précaires, et quels autres ne s'appliquent pas aux travailleurs précaires. De part l’analyse de nos cas, nous avons déterminé que certains éléments tels que l’attitude du délégué syndical vis-à-vis de sa fonction, les méthodes de communication en place ou encore la manière dont l’identité collective du groupe de travailleurs à été formée revêtent une importance primordiale dans la détermination, tant en nature qu’en intensité, de la participation syndicale des travailleurs en situation de précarité. À l’inverse, alors que les théories classiques en la matière semblent souligner l’importance de l’attitude syndicale, des activités individuelles ou encore des moyens de communication formels dans la détermination de l’intensité et la nature de la participation syndicale, nos observations nous permettent de relativiser la portée de ces éléments dans le cas d’une main d’œuvre précaire.Employment precarity can be defined as the accumulation of insecurities or as the lack of security in an employment relationship. This phenomenon still exists despite its evolutions across time. Precarity can take several forms : low income, low control on one's work schedule, fixed-term contracts, insufficient number of hours, lack of access to social protection or unionization. All those forms will have consequences on one's living conditions, such as material deprivation (inadequate housing, clothes, food, leisure), stress or adverse effects on health. In the meantime, unions organize and fight to grant their members the best working conditions achievable. When it comes to precarious workers, unions militate for better regulations, in order to mitigate the negative consequences of employment precarity. Members' participation to the daily life of their union is here considered to be capital : They are the only ones able to inform the union's head of the current situation, and they are the only ones able to implement means of pressure in order to create a balance of power with the company's management. It is noticeable however, that on a theoretical point of view, most models about union participation from members have their focus on the so-called "traditional" workforce, that presents no signs of precarity. The aim of our research is therefore to apply an analysis grid, initially tailored for "traditionnal" workforce, to a group of workers featuring precarity factors. By analyzing working conditions, current union strategies and participation in tis form and intensity, we intend to see how participation from precarious workers can differ from the one of a standard workforce. To do so, we have analyzed and compared two groups of unionized workers. Those two groups are unionized with the same union, belong to the same corporate group and operate in the same economic field. Yet, the form and intensity of their union participations differ significantly. Our analysis therefore consisted of meeting different actors of those two groups. Thanks to the results of our interviews, we highlighted the union strategies that allow one of the two groups to have a higher participation level. We also provide a feedback on the classical theories regarding union participation, to see which ones can be extended to precarious workers and which ones cannot. Through the analysis of our cases, we determined that certain elements such as the attitude of union representatives toward their function, communication methods or the way collective identity was built are very important to characterize union participation from a precarious workforce. Conversely, while classic theories about union participation seem to highlight the importance of union attitude of the workforce, individual activities or formal communication methods for union participation, our finding tend to mitigate the importance of the latter elements

The Acidic Probe LysoSensor™ is not Useful for Acrosome Evaluation of Cryopreserved Ram Spermatozoa

P. 363-367To try new acrosomal probes for assessing ram spermatozoa, we compared the LysoSensor™ probe, which labels acidic organelles, with the frequently used peanut agglutinin acrosomal probe (PNA‐PE; phycoerythrin as fluorescent moiety). The previous microscopic observations showed a lack of relationship of LysoSensor™ with acrosomal status. Semen was obtained from five rams and frozen in four pools. Each pool was analysed carrying out a triple staining propidium ioide/PNA‐PE/LysoSensor™ Green DND‐189 to test acrosome labelling, and a double staining SYBR‐14/PI, to assess sperm viability. Stained samples were analysed by flow cytometry. All measurements were replicated. Data were processed using agreement and repeatability tests. LysoSensor™ labelling did not agree with PNA (mean of differences: 30.8%; coefficient of agreement: 22.6%), confirming microscopic observations. Nevertheless, when LysoSensor™ was compared with SYBR‐14/PI, the agreement was high (mean of differences: −0.05%; coefficient of agreement: 5.07%). Repeatability of both methods was high and similar. LysoSensor™ did not seem to specifically stain the acrosome, but it may accumulate in the cytoplasm and label viable spermatozoa. Therefore, LysoSensor™ might not be used as an acrosomal probe in ram spermatozoa, but it could be used in other kind of studies, taking advantage of its pH sensitivity.S

Estrus cyclicity of spinogenesis: underlying mechanisms

Hippocampal spine density varies with the estrus cycle. The cyclic change in estradiol levels in serum was hypothesized to underlie this phenomenon, since treatment of ovariectomized animals with estradiol induced an increase in spine density in hippocampal dendrites of rats, as compared to ovariectomized controls. In contrast, application of estradiol to hippocampal slice cultures did not promote spinogenesis. In addressing this discrepancy, we found that hippocampal neurons themselves are capable of synthesizing estradiol de novo. Estradiol synthesis can be suppressed by aromatase inhibitors and by knock-down of Steroid Acute Regulatory Protein (StAR) and enhanced by substrates of steroidogenesis. Expression of estrogen receptors (ERs) and synaptic proteins, synaptogenesis, and long-term potentiation (LTP) correlated positively with aromatase activity in hippocampal cultures without any difference between genders. All effects due to inhibition of aromatase activity were rescued by application of estradiol to the cultures. Most importantly, gonadotropin-releasing hormone (GnRH) increased estradiol synthesis dose-dependently via an aromatase-mediated mechanism and consistently increased spine synapse density and spinophilin expression. As a consequence, our data suggest that cyclic fluctuations in spine synapse density result from pulsative release of GnRH from the hypothalamus and its effect on hippocampal estradiol synthesis, rather than from varying levels of serum estradiol. This hypothesis is further supported by higher GnRH receptor (GnRH-R) density in the hippocampus than in the cortex and hypothalamus and the specificity of estrus cyclicity of spinogenesis in the hippocampus, as compared to the cortex

Semen molecular and cellular features: these parameters can reliably predict subsequent ART outcome in a goat model

Currently, the assessment of sperm function in a raw or processed semen sample is not able to reliably predict sperm ability to withstand freezing and thawing procedures and in vivo fertility and/or assisted reproductive biotechnologies (ART) outcome. The aim of the present study was to investigate which parameters among a battery of analyses could predict subsequent spermatozoa in vitro fertilization ability and hence blastocyst output in a goat model. Ejaculates were obtained by artificial vagina from 3 adult goats (Capra hircus) aged 2 years (A, B and C). In order to assess the predictive value of viability, computer assisted sperm analyzer (CASA) motility parameters and ATP intracellular concentration before and after thawing and of DNA integrity after thawing on subsequent embryo output after an in vitro fertility test, a logistic regression analysis was used. Individual differences in semen parameters were evident for semen viability after thawing and DNA integrity. Results of IVF test showed that spermatozoa collected from A and B lead to higher cleavage rates (0 < 0.01) and blastocysts output (p < 0.05) compared with C. Logistic regression analysis model explained a deviance of 72% (p < 0.0001), directly related with the mean percentage of rapid spermatozoa in fresh semen (p < 0.01), semen viability after thawing (p < 0.01), and with two of the three comet parameters considered, i.e tail DNA percentage and comet length (p < 0.0001). DNA integrity alone had a high predictive value on IVF outcome with frozen/thawed semen (deviance explained: 57%). The model proposed here represents one of the many possible ways to explain differences found in embryo output following IVF with different semen donors and may represent a useful tool to select the most suitable donors for semen cryopreservation

Comparaison de l'absorption hydrique et en éléments minéraux de deux espèces de Proteaceae.

*INRA Antibes URIH Route des Colles Sophia Antipolis 06410 BIOT Diffusion du document : INRA Antibes URIH Route des Colles Sophia Antipolis 06410 BIO

Regulation de la steroidogenese des cellules de la granulosa humaine: aspects physiologiques et pharmacologiques

SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : T 81952 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc