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This dissertation focuses on investigating the consequences of today’s flexible labor market on the jobs, careers, and employment relationships of workers. On the one hand, due to the changing nature of the world of work, workers are increasingly required to self-regulate, and to be adaptable and proactive in their jobs and careers. On the other hand, the rise and spread of non-traditional employment arrangements such as temporary and platform work, bring about challenges to the traditional conceptualization of management of the employment relationship which has consequences for the workers themselves. The research presented in this dissertation therefore aims to answer the following research questions: What are the self-regulatory behaviors that individuals can implement at different stages of their careers, and what are their benefits? What can be done from an HRM point of view to manage the employment relationships of those who work in non-traditional employment arrangements? The first two empirical studies in this dissertation point at the importance of different self-regulatory behaviors and beliefs (such as job search self-efficacy and career adaptabilities) implemented by workers in multiple moments of their careers. The last two empirical studies highlight the relevance and consequences of different HRM practices in managing workers in non-traditional employment contexts such as temporary and platform work. Overall, both employees’ self-regulation and their employment relationships have an impact on employees, in terms of their attitudes, beliefs, behaviors, and well-being. In this dissertation, we discuss the theoretical, practical, and methodological implications of the results presented.

International audience

International audience

International audience; The ALCYONE multidimensional fuel performance code co-developed by the CEA, EDF and AREVA NPwithin the PLEIADES software environment models the behavior of fuel rods during irradiation incommercial Pressurized Water Reactors (PWRs), power ramps in experimental reactors or accidentalconditions such as Loss Of Coolant Accidents (LOCAs) or Reactivity-Initiated Accidents (RIAs). Asregards the latter case of transient in particular, ALCYONE is intended to predictively simulate theresponse of a fuel rod by taking account of mechanisms as close to physics as possible, encompassingall possible stages of the transient as well as various fuel/cladding material types and irradiationconditions of interest. On the way to complying with these objectives, its development and validationshall include tests on PWR-UO2 fuel rods with advanced claddings such as M5 under low pressurelowtemperature or high pressure-high temperature water coolant conditions.This paper first presents the ALCYONE V1.4 RIA-related features and modeling. It especially focuses onrecent developments dedicated on the one hand to non steady water heat and mass transport and onthe other hand to the modeling of grain-boundary cracking-induced fission gas release and swelling.This paper then compares some simulations of RIA transients performed on UO2-M5 fuel rods inflowing sodium or stagnant water coolant conditions to the relevant experimental results gained fromtests performed in either the French CABRI or the Japanese NSRR nuclear transient reactor facilities. Itshows in particular to what extent ALCYONE starting from base irradiation conditions it itselfcomputes is currently able to handle both the first stage of the transient, namely the Pellet CladdingMechanical Interaction (PCMI) phase, and the second stage of the transient, should the boiling crisisoccur.Areas of improvement are finally discussed with a view to simulating and analyzing further tests to beperformed under prototypical PWR conditions within the CABRI International Program.

In human and wildlife populations, the natural microbiota plays an important role in health maintenance and the prevention of emerging infectious diseases. In amphibians, infectious diseases have been closely associated with population decline and extinction worldwide. Skin symbiont communities have been suggested as one of the factors driving the different susceptibilities of amphibians to diseases. The activity of the skin microbiota of amphibians against fungal pathogens, such as Batrachochytrium dendrobatidis, has been examined extensively, whereas its protective role towards the cutaneous infectious diseases caused by Amphibiocystidium parasites has not yet been elucidated in detail. In the present study, we investigated, for the first time, the cutaneous microbiota of the Italian stream frog (Rana italica) and characterized the microbial assemblages of frogs uninfected and infected by Amphibiocystidium using the Illumina next-generation sequencing of 16S rRNA gene fragments. A total of 629 different OTUs belonging to 16 different phyla were detected. Bacterial populations shared by all individuals represented only one fifth of all OTUs and were dominated by a small number of OTUs. Statistical analyses based on Bray-Curtis distances showed that uninfected and infected specimens had distinct cutaneous bacterial community structures. Phylotypes belonging to the genera Janthinobacterium, Pseudomonas, and Flavobacterium were more abundant, and sometimes almost exclusively present, in uninfected than in infected specimens. These bacterial populations, known to exhibit antifungal activity in amphibians, may also play a role in protection against cutaneous infectious diseases caused by Amphibiocystidium parasites.

Lo Schema della Circolazione idrica sotterranea alla scala 1:50.000 costituisce il prodotto di sintesi elaborato e condiviso dai tre gruppi di lavoro incaricati dalla Provincia di Latina per la definizione dello stato di conservazione delle risorse idriche dei Monti Lepini e del settore pedemontano della Piana Pontina. Questo documento di sintesi nasce dall'analisi e dall'elaborazione di prodotti realizzati con metodologie diverse dai vari autori. Esso presenta degli ambiti territoriali, definiti da limiti geologici, per i quali si propongono delle indicazioni di tipo gestionale. La definizione di questi ambiti territoriali è il frutto di una analisi multidisciplinare basata su ricerche geochimiche classiche e degli isotopi, su modelli geologico-strutturali, su determinazioni piezometriche attuali e storiche e sull'idrogeologia quantitativa incentrata sul metodo del bilancio distribuito.

International audience; The I-SCC behavior of cold-worked stress-relieved (CWSR) Zircaloy-4 was investigated by means of internal pressure tests in both inert and gaseous iodine environments. I-SCC susceptibility was derived from tests on both un-irradiated and neutron-irradiated claddings tubes. Crack propagation rates were obtained from tests on pre-cracked tubes. The internal pressure tests conducted on un-irradiated cold-worked stress-relieved Zircaloy-4 cladding tubes in an iodine vapor environment were used to investigate the influence of loading mode (either constant pressure tests, constant circumferential strain rate tests, or constant circumferential strain tests) and test temperature (320DC to 488DC) on the I-SCC process. The experimental results obtained with different loading modes indicated that there is an apparent threshold hoop stress, below which I-SCC does not occur.The tests were simulated by finite element models using a specific viscoplastic constitutive equation. The I-SCC initiation and time-to-failure predictions were modelled by a Kachanov's damage law written with a hoop stress threshold. In the simulations, the Kachanov's law can be used in post-treatment of calculations or coupled with the viscoplastic constitutive equation for the cladding in order to simulate the initiation and the propagation of the I-SCC crack. The coupling was implemented in the finite-element code CAST3M.

International audience; The French Alternative Energies and Atomic Energy Commission (CEA) and its industrial partners electricite de France (EDF) and AREVA have been developing the collaborative platform PLEIADES for more than 10 years. This platform now supports the development of several state-of-the-art fuel performance codes Alcyone and Cyrano for Pressurized Water Reactor (PWR), Germinal V2 for Sodium Fast Reactors (SFR), Licos for innovative fuel elements and experimental irradiation devices, MAIA for Material Testing Reactors (MTR), etc.This paper first provides an up-to-date overview of the PLEIADES platform and then focuses on recent improvements of the thermomechanical modelling abilities recently introduced in PLEIADES's fuel performance codes. Various topics will be discussed and illustrated using Alcyone simulations of the PWR fuel rod in normal and off-normal situations, including LOCA and RIA- PWR fuel pellet cracking during the reactor start-up;- description of grain boundary decohesion in the fuel oxide during a RIA transient;- multi-fragments modelling of the PWR in 2D(r; );- various numerical improvements ;- finite strain modelling in 1D.

International audience; This paper presents 2D generalized plain strain simulations of the thermo-mechanical response of a pellet fragment and overlying cladding during a RIA transient. A fictitious hydride blister of increasing depth (25 to 90% of the clad thickness) is introduced at the beginning of the calculation. When a pre-determined hoop stress is exceeded at the clad outer surface, radial cracking of the blister is taken into account in the simulation by a modification of the mechanical boundary conditions. The hoop stress criterion is based on Finite Element simulations of laboratory hoop tensile tests performed on highly irradiated samples with a through-wall hydride blister. The response of the remaining clad ligament (beneath the cracked blister) to the pellet thermal expansion is then studied. The simulations show that plastic strains localize in a band orientated at ~ 45° to the radial direction, starting from the blister crack tip and ending at the clad inner wall. This result is in good agreement with the ductile shear failures of the clad ligaments observed post RIA transients. Based on a local plastic strain failure criterion in the shear band, ALCYONE simulations are then used to define the enthalpy at failure in function of the blister depth.

Lipase is an enzyme that finds application in biodiesel production and for detection of esters and triglycerides in biosensors. Matrix Assisted Pulsed Laser Evaporation (MAPLE), a technique derived from Pulsed Laser Deposition (PLD) for deposition of undamaged biomolecules or polymers, is characterized by the use of a frozen target obtained from a solution/suspension of the guest material (to be deposited) in a volatile matrix (solvent). The presence of the solvent avoids or at least reduces the potential damage of guest molecules by laser radiation but only the guest material reaches the substrate in an essentially solvent-free deposition. MAPLE can be used for enzymes immobilization, essential for industrial application, allowing the development of continuous processes, an easier separation of products, the reuse of the catalyst and, in some cases, enhancing enzyme properties (pH, temperature stability, etc.) and catalytic activity in non-aqueous media. Here we show that MAPLE technique can be used to deposit undamaged lipase and that the complex structure (due to droplets generated during extraction from target) of the deposited material can be controlled by changing the laser beam fluence.

Le acque sotterranee sono vitali per tutte le nazioni ed il loro uso sta crescendo rapidamente. Nel nostro paese circa il 98% dell'acqua destinata all'uso civile viene prelevata da corpi idrici sotterranei. Come riconosciuto a scala mondiale l'obiettivo ultimo nelle strategie sull'acqua è la gestione e lo sviluppo sostenibile della risorsa. La suddivisione negli usi e nelle competenze ha generato una barriera nella comunicazione tra operatori, tecnici politici ed utilizzatori.La gestione integrata della risorsa idrica è un approccio che promuove lo sviluppo e la gestione coordinata di acqua, territorio e risorse in modo da massimizzare il risultato economico ed il benessere sociale in una modalità equa senza compromettere la sostenibilità degli ecosistemi. Gli elementi di base che guidano la sostenibilità sono tre: efficienza economica, sostenibilità ambientale e equità sociale. Per implementare un approccio di gestione integrata sono necessarie le seguenti azioni chiave: a)protezione ambientale, comprendente politica, legislazione e regolamentazione, struttura di finanziamento e incentivo; b) ruoli istituzionali, considerando i modelli che considerano il bilancio acquifero e fluviale, centrale-locale, l'interesse pubblico e privato; c) struttura di gestione, tra cui la valutazione delle risorse, la gestione di informazioni e l'allocazione delle risorse e gli strumenti di tutela. Acque sotterranee ed acque superficiali sono strettamente legate e nell'approccio di gestione integegrata devono essere gestite come un'unica risorsa. Un aspetto chiave della sostenibilità delle acque sotterranee è il bilanciamento tra risorse disponibili e la crescita di domanda dell'uso dell'acqua.

Le acque sotterranee sono vitali per tutte le nazioni ed il loro uso sta crescendo rapidamente. Nel nostro paese circa il 98% dell'acqua destinata all'uso civile viene prelevata da corpi idrici sotterranei. Come riconosciuto a scala mondiale l'obiettivo ultimo nelle strategie sull'acqua è la gestione e lo sviluppo sostenibile della risorsa. La suddivisione negli usi e nelle competenze ha generato una barriera nella comunicazione tra operatori, tecnici politici ed utilizzatori.La gestione integrata della risorsa idrica è un approccio che promuove lo sviluppo e la gestione coordinata di acqua, territorio e risorse in modo da massimizzare il risultato economico ed il benessere sociale in una modalità equa senza compromettere la sostenibilità degli ecosistemi. Gli elementi di base che guidano la sostenibilità sono tre: efficienza economica, sostenibilità ambientale e equità sociale. Per implementare un approccio di gestione integrata sono necessarie le seguenti azioni chave: a)protezione ambientale, comprendente politica, legislazione e regolamentazione, struttura di finanziamento e incentivo; b) ruoli istituzionali, considerando i modelli che considerano il bilancio acquifero e fluviale, centrale-locale, l'interesse pubblico e privato; c) struttura di gestione, tra cui la valutazione delle risorse, la gestione di informazioni e l'allocazione delle risorse e gli strumenti di tutela. Acque sotterranee ed acque superficiali sono strettamente legate e nell'approccio di gestione integegrata devono essere gestite come un'unica risorsa. Un aspetto chiave della sostenibilità delle acque sotterranee è il bilanciamento tra risorse disponibili e la crescita di domanda dell'uso dell'acqua.

Plant nursery industry makes extensive use of non-biodegradable plastic pots (polypropylene, PP); in Italy, it is estimated an annual consumption of about 440 million PP pots which, at the end of their use, represent an expensive waste to be disposed of; therefore, the replacement of PP pot with similar products based on biodegradable materials, may reduce significantly the environmental impact of this sector. ECO-POT project aims at a cost-effectively production and successive field validation of biodegradable pots realized in different sizes; the mechanical properties of pots, i.e. resistance to lateral deformation and crushing, and rate of biodegradation should match needs of both operators and consumers. In particular, the biodegradation will be tested on plantable pot which are left intact on the root ball and planted into the field. In this case pots are designed to allow root to grow through the container walls and to decompose rapidly after being planted. In addition, the rate of biodegradation will be also tested on pots which are designed to be removed before final planting, thus speculating on the compostability of the used containers (test ISO UNI 14855-1) Different commercial biodegradable products, alone or mixed, will be tested. ECOPOT project involves different plant nursery farms located in Pistoia; up to 10,000 ornamental plants, placed in pots of different sizes, in different environments and belonging to 10 different species / varieties, will be tested. The most important expected results are: reduction in the consumption of non-renewable resources; economic benefits for nurseries gained in the international markets thanks to the adoption of recognizable low environmental impact trademarks (ECOLAB).

Static composting of olive mill waste (OMW) can be regarded as an easy and convenient way for the disposal and valorisation of such agro-industrial by-product. We investigated the bacterial community dynamics during OMW composting by applying a culture-independent molecular approach based on denaturing gradient gel electrophoresis (DGGE) profiling and Illumina next generation sequencing (NGS) of amplified 16S rRNA genes. DGGE analysis indicated the presence of a very high bacterial diversity in both the OMW and the composting mixture and the occurrence of a rapid succession of different bacterial populations throughout the process. Indeed, only few populations were shared among all the samples, while most seemed peculiar of the different phases of biotransformation of OMW into mature compost.NGS analysis allowed the identification of these populations. Actinobacteria were abundant in the OMW, declined at the beginning of the active/thermophilic phase and then represented the predominant populations during the curing/mesophilic phase. Interestingly, while in the OMW most Actinobacteria belonged to the family Microbacteriaceae, the compost in the curing phase featured a high abundance of Pseudonocardiaceae, mostly represented by the moderately halophilic Prauserella genus. As expected, the most abundant populations found in the active phase, when the temperature reached 60°C, were the Bacilli, particularly those belonging to the thermophilic, spore-forming Geobacillus genus. Finally, the compost in the maturing phase was mainly characterized by an even distribution of bacteria belonging to the orders Actinomycetales, Sphingobacteriales, Burkholderiales, Xanthomonadales and Rhizobiales.

Herbal species different from the official bearberry, Arctostaphylos uva-ursi, are sold through conventional markets and also through non-controlled Internet websites, putting consumer safety at risk owing to the lack of quality control. Recently, Arctostaphylos pungens has become one of the most used species as a raw material for herbal medicines and dietary supplements in the place of official bearberry, a plant used for the treatment of various urinary disorders. A fingerprint identification based on an integrated application of different analytical techniques (HPTLC, NMR, HPLC-DAD and LC-ESI-MS) is here described to distinguish A. uva-ursi from A. pungens. The HPTLC and HPLC-DAD fingerprints resulted the simplest methods to differentiate the two species, whereas LC-ESI-MS was more useful to quantify arbutin, the main component of bearberry, and to evaluate its different content in the two species. This multidisciplinary study showed for the first time a specific phytochemical fingerprint of the new species A. pungens.

Composting of Olive Mill Waste (OMW) may represent an easy and convenient solution to the disposal of such biowaste. We investigated the microbial community dynamics during OMW composting to better understand the role of microorganisms during this process. Physicochemical analyses indicated that a strong microbial activity, particularly during the thermophilic phase, led to the biotransformation of OMW into an high-quality compost. Culture-dependent and cultureindependent microbiological analyses showed strong modifications of both the size and the diversity of the bacterial community that were clearly related to the different phases of OMW composting. Taken together these results suggest the rapid succession of specialized bacterial populations with key roles in the organic matter transformation process.

Objective. Empirical observations show that rowers demonstrate higher efficiency working on the rowing ergometer than working on water. The aim of the study was to determine the difference in efficiency levels and to verify its validity using a model based on fluid dynamics principles. Methods. A part of work done by rowers is lost in boat deformation and in the friction caused by the oarblades moving through the water. Load conditions for training on a rowing ergometer need to be increased by a certain quantity with respect to those set for on-water training. Results. Times were measured during on-water runs and rowing ergometer tests. Discussion and Conclusions. Times measured during on-water runs matched fairly well those calculated on rowing ergometer tests.