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A travers le declin de la part de la remuneration du travail dans la valeur ajoutee depuis les annees 1980, cet article examine la degradation continue et generalisee du rapport salarial fordiste. Il se concentre sur le sort differencie du salaire direct et du salaire indirect.

In Sub-Saharan Africa, unprecedented population growth, concomitant with limited industrialisation and job creation, have changed the configurations of rural-urban linkages in recent decades. Indeed, as primate cities do not act as strong engines of growth, territorial dynamics are rapidly being reshaped by renewed flows of people, goods, services and information within and between economic sectors, and between rural and urban areas. Rural densification and the fast expansion of small and medium-sized cities is one manifestation of these changes. As a result of silo thinking about rural and urban in most national strategies, plus the widespread informal economy and limited available statistics in the region, these new rural-urban linkages and their contribution to socioeconomic dynamics remain underexplored. Contributing to fill this gap, the aim of this paper is to present and test a method to assess rural-urban linkages and their possible role in territorial development in southern countries. We use a holistic approach and adopt an original posture, taking rural areas as the point of reference. Our method sets proxy indicators for specific information that is missing on rural-urban linkages. These indicators are then used to build a typology of territories according to potential rural-urban linkages, using a multivariate analysis and clustering. When applied to the case of Zimbabwe, the results reveal three types of districts, which differ in terms of the nature, intensity, direction and potential of rural-urban linkages for territorial development. We discuss the method’s suitability in a diagnostic phase and how it could feed strategic thinking to mainstream rural-urban linkages in territorial development actions.

L’article rend compte d’un fait théorique que les débats à propos du régime capitaliste ont négligé, la théorie de la régulation (TR) propose une grille d’analyse permettant de saisir la dynamique d’espaces spécifiques et les processus de différenciation qui les structurent. S’appuyant sur les travaux ayant exploré les variétés sectorielles et territoriales, nous montrons que les concepts de la TR permettent de fonder une analyse méso-économique, pour laquelle nous proposons une grille de lecture qui identifie trois canaux de différenciation et situe les espaces méso dans une variété de relations avec les dynamiques macroéconomiques., This contribution aims to understand an overshadowed fact: regulation theory—far from being restricted to macroeconomics—is relevant for grasping the dynamics of meso-economic arenas and the processes of differentiation that structure them. Drawing on a wealth of works that have characterized these processes in a wide range of sectors and territories, we show how regulationist concepts shed light on meso-economic patterns. We develop a framework that identifies three main carriers of differentiation within meso-economic arenas and sheds light on a variety of evolutive meso-macro configurations.

The question of how this spending affects the economic growth is a question as old as economics. While the 19th century showed their countercyclical growth during the phase of depression of the business cycle followed by ratchet effects when economic context is improving, the 20th century has studied the causes of their growth. Economic causes insist first on the correction on income losses and then introduce causality as regards with the dynamics of capital accumulation. At the end of the 1980s, a new assumption (Lucas 1988, Fontvieille 1990) suggests that social spending would have become a driver of growth. This paper searches to verify this assumption. In order to do so, it focuses on the european pathway of social spending development since the 1960s to 2014. It is shown that insofar as social spending is still sensitive to the two last business cycle phase of depression, the 1980s assumption is not invalidated. But the assumption is not verified for other reasons than the expected ones. While social spending avoiding the fall of income used to be countercyclical, the other ones, dedicated to the production of the quality of the people, are becoming acyclical.

International audience; This article applies the capabilities approach in order to analyse microcredit as a tool for resource conversion permitting poor households to take advantage of latent opportunities. This approach calls for linking microcredit with the choices of the poor themselves. A sample of 290 rural households from the Madagascar highlands has been surveyed two consecutive years. To characterize the dimensions of poverty based on social practices of the poor and to inform about the most relevant dimensions available for a conversion process, data have been processed by a factor analysis. A hierarchical classification then permits the distribution of the households over three capabilities levels. Finally, an ordered multinomial logit brings out how microcredit influences the likelihood that a household receiving such a loan will reach a higher capability level. The main findings indicate that the microcredit represents a robust means to obtain a higher level of capability regardless the starting situation. Moreover, when the process of borrowing endures, poor households enter into a learning process which increases the effect of microcredit. Regardless of the gender of the household head, microcredit increases the probability to reach an enhanced level of capability, except for the poorest household headed by a woman. The education of the head of household improves the effect of microcredit only if the productive system implemented needs competences related to the educational attainment. JEL classification: O12, I32, G21

International audience; This chapter discusses the way in which the social surplus is distributed and, crucially, used—that is, accumulation regimes. Historical observation shows that accumulation—the process of adding productive capital to the previously invested amount of capital—undergoes long periods of stability, followed by periods of instability and crisis. Thus, especially Régulation theory and the Social Structure of Accumulationapproach set out to study the dynamics of production, consumption and the distribution of income through institutional frameworks specific in time and location and which underpin macroeconomic regularities. In this way, authors demonstrate that the evolutionary nature of the economy implies that economics should not assume a canonical accumulation regime but rather be concerned with a much broader variety of regimes.

We have raised monoclonal antibodies against KLK6 and constructed a ‘sandwich’ type immunoassay using 8A8G3 as capture and 3H3E9 as tracer antibodies. 8A8G3 bound to one side of KLK6, whereas 3H3E9 probably bound near its catalytic site. The assay did not detect complexed forms of KLK6, indicating that it quantifies only free KLK6 (fKLK6). fKLK6 was higher in serum of patients with ovarian cancer (11.34 μg/l±1.37) than in controls (3.39 μg/l±0.42). The cerebrospinal fluid contained high concentrations of fKLK6 (257–965 μg/l). This assay could facilitate the evaluation of fKLK6 in human diseases.

International audience; This article brings together three approaches belonging to historical institutionalism : the German historical school, the original American institutionnalism, and the French Régulation theory. It enlightens the methodological principles shared by these approaches and analyses their application to the process of theoretical elaboration.; Cet article associe trois approches issues de l’institutionnalisme historique : l’école historique allemande, l’institutionnalisme américain originel et la théorie de la régulation. Il en dégage les principes méthodologiques partagés et analyse leur application au processus d’élaboration théorique.

Apparue dans le contexte économique de la crise structurelle ouverte dans les années 1970, la théorie de la régulation (TR) a d’emblée défini son programme de recherche à partir de l’analyse du capitalisme et de la compréhension de ses changements. Sa spécificité a été de revenir sur l’étude du processus d’accumulation du capital et sa réalisation, instable, à travers l’évolution des rapports sociaux fondamentaux. Ce faisant, elle réaffirmait l’impasse d’une analyse économique unifiée par l’h...

Resume Le cancer de la prostate (CaP) a l’incidence la plus elevee de tous les cancers chez les hommes de plus de 50 ans et represente la deuxieme cause de mortalite par cancer. Le prostate-specific antigen (PSA) est le marqueur le plus couramment utilise pour le diagnostic et le suivi du cancer de la prostate. Le PSA, aussi appele kallicreine 3, est un membre de la famille des kallicreines humaines de type serine proteases qui circule dans le sang sous forme de complexes avec des inhibiteurs de proteases et sous forme libre. Cependant, le PSA libre est aussi un melange heterogene de differentes formes moleculaires : proPSA, formes matures intactes ou clivees. La signification clinique de ces differentes formes n’est pas encore connue, mais leur mesure specifique dans le serum pourrait ameliorer la specificite du PSA pour detecter un cancer ou predire l’evolution d’un traitement. D’autres kallicreines comprenant les kallicreines 2, 11, 4, 14 et 15 sont aussi des marqueurs emergeant comme marqueurs complementaires au PSA pour le cancer de la prostate. Une detection multiple des differentes formes moleculaires du PSA ainsi que de ces kallicreines, en addition avec le PSA total, pourrait ameliorer l’utilite diagnostique du PSA et pourrait ajouter une valeur pronostique en apportant des informations cliniques sur la progression du cancer.

International audience; After fifty years of almost continuous economic growth in Thailand, it is now possible to re-evaluate the developmental process of the education system. Until now, the structural indicators of education development that have been mainly used are the level and pace of the increases in public expenditure on education, the effect of increasing enrolment on social mobility, and the private and public distribution of investment in education. The impact of these factors undeniably offers a better understanding of the quantitative advances in education. However, the dynamics of the education system nowadays encounter structural limits related to both the integration of what is now widespread education within the social structures and Thailand's contribution to globalization. As a result, the contribution of education to the growth regime is increasingly questioned. The aim of this paper is to use a historical approach to explore this evolution. Theoretical and historical perspectives are combined within a quantitative history methodology, drawing on new time-series.

A dodecapeptide phage-displayed library was screened with the mouse monoclonal antibody (mAb) 2E3C2 which competed with human antibodies for the binding to the HCV c100 recombinant protein. Four mimotopes shared a consensus motif with the HCV 1701-1707 sequence corresponding to the carboxyl-terminal domain of the non-structural protein NS4A. However, these mimotopes reacted with 2E3C2 only, whereas the corresponding NS4 epitope defined at the sequence 1698-1709 and displayed on phage was recognized by both 2E3C2 and sera from HCV infected patients. Using the Spot method of multiple peptide synthesis and alanine replacement analysis, the respective reactivities of mAb 2E3C2 and anti-NS4A human antibodies against NS4 were shown to be directed against two slightly different overlapping minimal linear sequences and to involve different critical residues. The phage clone displaying the NS4 epitope was used to study the specific recognition of this epitope by different individual HCV positive sera as well as by two seroconversion panels of sera from HCV infected patients. Compared with the detection by RIBA of the different HCV antigens and c100 particularly, these results indicated that the antibodies directed against the NS4 (1698-1709) epitope were produced early during the course of the disease and decreased later.

The hepatitis C virus (HCV) nonstructural 3 (NS3) protein is composed of an amino terminal protease and a carboxyl terminal RNA helicase. NS3 contains major antigenic epitopes. The antibody response to NS3 appears early in the course of infection and is focused on the helicase region. However, this response cannot be defined by short synthetic peptides indicating the recognition of conformation-dependent epitopes. In this study, we have screened a dodecapeptide library displayed on phage with anti-NS3 mouse monoclonal antibodies (mAbs) that compete with each other and human anti-HCV NS3 positive sera. Two peptides (mimotopes) were selected that appeared to mimic an immunodominant epitope since they were recognized specifically by the different anti-NS3 mAbs of the study and by human sera from HCV infected patients. Homology search between the two mimotopes and the NS3 sequence showed that one of the two peptides shared amino acid similarities with NS3 at residues 1396-1398 on a very accessible loop as visualized on the three-dimensional structure of the helicase domain whereas the other one had two amino acids similar to nearby residues 1376 and 1378. Reproduced as synthetic dodecapeptides, the two mimotopes were recognized specifically by 19 and 22, respectively, out of 49 sera from HCV infected patients. These mimotopes allowed also the detection of anti-NS3 antibodies in sera of HCV patients at the seroconversion stage. These results suggest that the two NS3 mimotopes are potential tools for the diagnosis of HCV infection.

Dès son démarrage, au cours des années 1960, la croissance des pays asiatiques s’est appuyée sur l’éducation. Sur la base de résultats indéniables, les modalités de son expansion ont contribué à forger l’idée de la performance scolaire de ces pays. Toutefois, ce développement éducatif présente des limites, liées à leurs spécialisations internationales et à l’insertion de l’éducation, désormais généralisée, dans les structures sociales. À partir du cas de la Thaïlande, cet article s’interroge sur le caractère soutenable de ce modèle de développement de l’éducation à long terme. Since the Asian economies began to emerge in the 1960s, education has been the basis of this development. The undeniable results and the way the countries have developed has shaped the perception of their educational performance. However, this educational development has its limits, in view of their international specialisations and the impact on society of the generalisation of education now achieved. Using Thailand as a case study, this article investigates the sustainable nature of this educational development model in the long-term. Desde su arranque, durante los años sesenta, el crecimiento de los países asiáticos se apoyó en la educación. Basándose en unos resultados innegables, las modalidades de su expansión contribuyeron a forjar la idea del rendimiento escolar de estos países. Sin embargo, tal desarrollo educativo presenta unos límites, vinculados con sus especializaciones internacionales y con la inserción de la educación, ahora generalizada, en las estructuras sociales. A partir del caso de Tailandia, este artículo se interroga sobre el carácter sostenible de este modelo de desarrollo de la educación a largo plazo.

Prostate-specific antigen (PSA), a 237-amino acid glycoprotein, encoded by the hKLK3 gene, is widely used as a serum marker for the diagnosis and management of prostate cancer. We report here the localization of a conformational epitope recognized by the anti-total PSA monoclonal antibody (mAb) 11E5C6, by proteolytic degradation of mAb-bound antigen followed by mass spectrometric analyses of the peptides generated. These two technologies, combined with molecular display, allowed the identification of amino acid residues contained within three different peptides distant on the PSA sequence, but close in the PSA three-dimensional structure, that may be part of the mAb 11E5C6 epitope. The last four C-terminal amino acid residues are included in this epitope, as well as certain other C-terminal residues between Y225 and T232. The involvement of the PSA C-terminal end in the mAb 11E5C6 epitope was confirmed by western blotting experiments with the recombinant protein proPSA-RP1, resulting from the cloning of an alternative transcript of the hKLK3 gene, in which the PSA C-terminal end was deleted and replaced by another sequence. Although the anti-total PSA mAb 5D5A5 used as a control bound proPSA-RP1, mAb 11E5C6 did not. The requirement of the C-terminal end for the recognition by mAb 11E5C6 may be useful for the discrimination of PSA-related forms.

Prostate specific antigen (PSA) is a protease which is characteristic of the prostate. It is widely used as a serum marker for the early diagnosis of prostate cancer (PCa). Nevertheless, for concentrations between 4 and 10 ng/mL, PSA does not enable PCa to be distinguished from benign diseases, such as benign prostate hyperplasia (BPH). In sera, the use of a ratio between free PSA (PSA uncomplexed with protease inhibitor) and total PSA (free PSA and PSA bound to alpha-1 anti-chymotrypsin) enables the "gray zone" to be reduced, but an important proportion of patients are still wrongly classed. Using two-dimensional electrophoresis, we demonstrated using 52 PCa and 40 BPH well-documented clinical cases that BPH sera show a significantly greater percentage of low-molecular-weight free PSA elements (IwPSA) than PCa sera. In our study, the use of a ratio between IwPSA and standard free PSA enables the correct diagnosis of 100% of PCa and 82.5% of BPH cases as against when 73.1% and 42.5% respectively were correctly diagnozed using the total PSA and the free/total PSA ratio. This important finding may be related to differences in the mechanism secreting PSA from the prostate into the bloodstream. We have shown how a tissue marker may be turned into a powerful tumor marker by events probably unrelated to its expression.

The synthetic peptides E30D and D10P that correspond to prostate specific antigen (PSA) sequences 60-91 and 78-89, respectively, and contain the kallikrein loop were used to immunize mice to obtain anti-PSA monoclonal antibodies (mAbs).Antipeptide mAb characteristics were studied using biosensor technology and enzyme-linked immunosorbent assay, and analyzing the mAb effects on PSA-alpha1-antichymotrypsin (ACT) complex formation and PSA enzymatic activity. Epitope mapping of these mAbs was performed using overlapping peptide synthesis on nitrocellulose membrane.Anti-E30D mAbs bound PSA coated on the solid phase only, whereas anti-D10P mAbs recognized PSA in detection as well as in capture. However, these mAbs appeared to be anti-total PSA mAbs. Anti-E30D and anti-D10P mAbs were directed against linear epitopes corresponding to residues H74-Y77 and N84-R88, respectively, of the PSA sequence. Anti-D10P mAb recognition of PSA and PSA-ACT complex was equimolar, although an existing molecular model suggested that the sequence corresponding to anti-D10P mAb epitope was involved in the interaction site of PSA with ACT. Furthermore, we were unable to inhibit the enzymatic activity of PSA as well as PSA-ACT complex formation. Finally, the epitope N84-R88 overlapped the cleavage site R85-F86 of PSA.The linear anti-D10P mAb epitope is located outside of the PSA-ACT binding site. However, these mAbs may be of value for evaluating the presence of different molecular PSA forms in sera.

Prostate-specific antigen (PSA), the main marker for prostate cancer (PCa), is released from the prostate into the blood stream at nanogram level and may increase in PCa and nonmalignant disease such as benign prostate hyperplasia (BPH). More recently, advantage was taken of PSA's ability to bind to protease inhibitors in serum in order to improve discrimination between PCa and BPH, using the free PSA to total PSA ratio. The understanding of this phenomenon at molecular level, which is still unknown, may promise new improvements in the field of diagnostics. For this purpose, we determined the pattern of PSA forms in PCa and BPH sera, using the high resolving power of two-dimensional electrophoresis (2-DE) in conjunction with the high sensitivity of chemiluminescence detection. Serum PSA differs drastically from seminal PSA: apart from complexed forms, serum PSA shows few cleaved forms. Moreover, 2-DE patterns from PCa are relatively homogeneous, whereas patterns from BPH may in some cases present a higher proportion of cleaved forms and in other cases present slightly more basic spots. We therefore demonstrated, for the first time, that an increase in the free to total PSA ratio in BPH cases may be due to cleaved PSA forms (which are enzymatically inactive and unable to bind inhibitors), or possibly related to basic free PSA, which may represent the zymogen forms.

International audience; Objectives: Annexin A3 (ANXA3) is a potential marker for prostate cancer (PCa). We aimed to develop robust immunoassays suitable for quantifying ANXA3 in urine samples obtained following digital rectal examination (DRE) in order to facilitate the diagnostic performance evaluation of this marker. Design and methods: Anti-ANXA3 monoclonal antibodies were generated and their epitopes mapped. Two different ANXA3 assay prototypes were established on the VIDAS (R) automated immunoanalyser and analytical validation was carried out using post-DRE urine samples obtained from patients with PCa (n = 23) or benign prostate hyperplasia (n = 31). Results: The assays had the same capture antibody (TGC44) but different detection antibodies (13A12 or 5C5), recognizing novel distinct epitopes. Both had a lower limit of quantification

Dengue virus (DV) infection is the most common mosquito-born viral disease of public health significance. Though most patients only suffer from flu-like symptoms, a small group of patients experiences more severe forms of the disease. The viral nonstructural protein 1 (NS1), a secreted protein correlating with viremia, is a key element used for dengue diagnosis with potential implications in severe dengue prognosis. Capture-ELISAs for the early detection of the NS1 protein in the sera during the acute febrile stage are commonly used in routine by diagnostic laboratories. In this study, the detection of NS1 protein in DV-infected material was assessed by an alternative method combining a single NS1-directed monoclonal antibody and the SELDI-TOF/MS technology. According to the epitope mapping, the antibodies used are mainly directed against an immuno-dominant peptide located on the C-terminal part of the protein. The NS1 SELDI-TOF assay is specific, has a sensitivity level close to capture-ELISAs and is potentially useful for a coupled serotyping/detection assay or for the detection of subtle post-translational modifications on the protein. J. Med. Virol. 84:490–499, 2012. © 2011 Wiley Periodicals, Inc.

International audience; Prostate-specific antigen (PSA) is a serum marker that is widely used for the diagnosis of prostatic diseases. Various subforms of free PSA, which are associated with prostate cancer differently, have been identified in sera. Thus, specific detection of certain subforms could permit discrimination between benign and malignant cases. Although the monoclonal antibody 5D3D11 displays the desired selectivity, its relative weak binding affinity prevents its development into an effective diagnostic tool. The directed-evolution strategy presented here succeeds in enhancing affinity and immunoassay sensitivity while maintaining selectivity. Starting without structural data, we constructed four independent phage-display single-chain variable fragment (scFv) libraries targeting hot spots from CDR-L1, H1, H2, and H3. Mutations derived from each library were combined, yielding further affinity gains. This constitutes the first demonstration of additivity for independently selected complementarity-determining region (CDR) hot-spot mutations. The X-ray structure of the Fab′ 5D3D11–PSA complex (after it became available) inspired the design of two new libraries targeting CDR-L3 that resulted in other higher-affinity variants. Attempts at combining the new variants with previous ones did not result in further gains, suggesting that mutations from the two strategies provide alternative but noncomplementary solutions for affinity enhancement of 5D3D11. The results can be interpreted to provide a plausible explanation for the observed lack of additivity. Finally, with respect to the wild-type scFv, the best binders show an enhancement of sensitivity in sandwich immunoassay. Its ability to discriminate between prostate cancer sera and benign prostatic hyperplasia sera has now been confirmed through the dosage of 63 patients.

Human prostate-specific antigen (PSA or human kallikrein-related peptidase 3) present in small quantities in the sera of healthy men becomes elevated in prostate cancer (PCa) and other prostate disorders. The ability to identify the free PSA fraction associated with PCa could increase the reliability of the PSA diagnostic test. Here we present the crystal structure of human PSA from seminal fluid in a sandwich complex with two monoclonal antibodies (mAbs). MAb 5D5A5 captures total PSA with exceptionally high affinity, and mAb 5D3D11 selectively discriminates between free PSA subforms that are more abundant in sera from patients with PCa. Although the antigen is not of seric origin, several insights into cancer diagnosis can be discerned from this complex. MAb 5D3D11 recognizes a PSA conformation different from that previously reported. Interacting with the kallikrein loop, the PSA N-linked glycan attached to asparagine 61 is an uncommonly complex sialated triantennary chain. O-linked glycosylation is observed at threonine 125. The description of how PSA subforms in prostatic fluid can be discriminated using pairs of antibodies is a first step in the design of new strategies that are capable of real discrimination among PSA subforms, which will lead to the formulation of more reliable diagnostic tests. In a companion article [Muller, B. H., Savatier, A., L'Hostis, G., Costa, N., Bossus, M., Michel, S., et al. (2011). In vitro affinity maturation of an anti-PSA antibody for prostate cancer diagnostic assay. J. Mol. Biol.], we describe engineering efforts to improve the affinity of mAb 5D3D11, a first step towards such goal.

Human prostate-specific antigen (PSA or KLK3) is an important marker for the diagnosis and management of prostate cancer. This is an androgen-regulated glycoprotein of the kallikrein-related protease family secreted by prostatic epithelial cells. Its physiological function is to cleave semenogelins in the seminal coagulum and its enzymatic activity is strongly modulated by zinc ions. Here we present the first crystal structure of human PSA in complex with monoclonal antibody (mAb) 8G8F5 that enhances its enzymatic activity. The mAb recognizes an epitope composed of five discontinuous segments including residues from the kallikrein loop and stabilizes PSA in an "open and active conformation" that accelerates catalysis. We also present the crystal structure of PSA in complex with both the mAb 8G8F5 and a fluorogenic substrate Mu-KGISSQY-AFC, derived from semenogelin I. By exploiting the inhibition of PSA by zinc ions, we were able to obtain a substrate acyl intermediate covalently linked to the catalytic serine, at pH 7.3 but not at pH 5.5. Moreover, the inhibition of PSA activity by zinc was found to be modulated by pH variations but not by the antibody binding. The correlation of the different data with the physiological conditions under which PSA can cleave semenogelins is discussed.

The hepatitis C virus (HCV) nonstructural 3 (NS3) protein is composed of an amino terminal protease and a carboxyl terminal RNA helicase. NS3 contains major antigenic epitopes. The antibody response to NS3 appears early in the course of infection and is focused on the helicase region. However, this response cannot be defined by short synthetic peptides indicating the recognition of conformation-dependent epitopes. In this study, we have screened a dodecapeptide library displayed on phage with anti-NS3 mouse monoclonal antibodies (mAbs) that compete with each other and human anti-HCV NS3 positive sera. Two peptides (mimotopes) were selected that appeared to mimic an immunodominant epitope since they were recognized specifically by the different anti-NS3 mAbs of the study and by human sera from HCV infected patients. Homology search between the two mimotopes and the NS3 sequence showed that one of the two peptides shared amino acid similarities with NS3 at residues 1396-1398 on a very accessible loop as visualized on the three-dimensional structure of the helicase domain whereas the other one had two amino acids similar to nearby residues 1376 and 1378. Reproduced as synthetic dodecapeptides, the two mimotopes were recognized specifically by 19 and 22, respectively, out of 49 sera from HCV infected patients. These mimotopes allowed also the detection of anti-NS3 antibodies in sera of HCV patients at the seroconversion stage. These results suggest that the two NS3 mimotopes are potential tools for the diagnosis of HCV infection.

Background: Prostate-specific antigen (PSA) is an important marker for the diagnosis and management of prostate cancer, and the free PSA/total PSA ratio has been shown to be efficient for distinguishing prostate cancer from benign prostatic hyperplasia. We report here the characterization of seven mouse monoclonal antibodies (mAbs) and the partial localization of two conformational epitopes identified by anti-free PSA mAbs.Methods: The mAbs were studied by competition and sandwich assays, and the epitope localization of the two anti-free PSA mAbs (6C8D8 and 5D3D11) was performed using phage displayed peptide libraries and molecular modeling.Results: The seven mAbs were classified into three groups according to their recognition specificities and their ability to inhibit the enzymatic activity of PSA and the formation of PSA-α1-antichymotrypsin (ACT) complex. Among the anti-free PSA mAb group, 6C8D8 recognized the phage displayed peptide RKLRPHWLHFHPVAV, two parts of which presented similarities with two regions distant on the PSA sequence but joined in the tridimensional structure. mAb 5D3D11 recognized the peptide DTPYPWGWLLDEGYD, which is similar to a PSA region located on the board of the groove containing the PSA enzymatic site. Both epitopes were located in the theoretical ACT binding site described previously. Moreover, these mAbs were able to inhibit the enzymatic activity of PSA.Conclusions: These epitope localizations are in agreement with the ability of both mAbs to inhibit enzymatic activity and ACT fixation. The results presented here could bring information for the generation of clinically relevant PSA assays.

Insertion training. Towards new forms of employment ? Linked with the seriousness and duration of unemployment, insertion is a process now taking shape between school and employment. The transition period is becoming longer and more complex, especially under the effect of the government employment policy. Training is becoming increasingly important Insertion patterns tend to show that the process is coherent. No theoretical body of work specifically covers insertion. This is doubtless a sign that it is an emerging feature that still depends strongly on empirical attitudes. Today the diversity of insertion patterns highlights the need for progress in theoretical interpretation based on hypotheses concerning the period itself. With this in mind, it is suggested that insertion training can be considered as an occupation corresponding to ongoing changes in the employment system., Liée à l'ampleur et à la durée du chômage, l'insertion correspond à un processus en voie de structuration entre l'école et l'emploi. Cette période de transition s'allonge et se complexifie, en particulier sous l'influence de la politique publique de l'emploi. Les trajectoires d'insertion tendent à montrer que ce processus a une cohérence. Aucun corpus théorique ne traite l'insertion de manière spécifique ; cela témoigne sans doute d'un objet en voie de constitution, encore fortement tributaire des remontées empiriques. Aujourd'hui, leur diversité engage à avancer dans la voie de la restitution théorique à partir d'hypothèses concernant la période elle-même. Dans cette optique, nous considérons que la formation-insertion peut être assimilée à une activité correspondant à des transformations en cours dans le système de l'emploi., La formacion-insercion. Hacia una nueva forma de empleo ? Relacionada con la importancia y la duraciôn del paro, la inserción corresponde a un proceso que se está estructurando entre la escuela y el empleo. Este periodo de transición se va alargando y haciendo más complejo, a causa, especialmente, del peso de la politica estatal del empleo. Las trayectorias de inserción muestran que este proceso tiene cierta coherencia. Quada que hace falta, para el estudio de la inserción, de un modelo teorico especifico, cuya elaboración está en marcha, aunque todaria demasiado sometida a las observaciones empiricas. Hoy por hoy, lo que hay que hacer, a causa de la diversidad de los casos, es avanzar por la via teorica a partir de hipótesis relativas al periodo misno. Desde este punto de vista, puede la formación-inserción considerarse como una actividad que corresponde a unas transformaciones en curso en el sistema del empleo., Canals Valérie, Michel Sandrine. La formation-insertion. Vers une forme nouvelle d'emploi ?. In: Sciences de la société, n°36, 1995. Travail, emploi, formation. pp. 111-126.

Prostate-specific antigen (PSA) is widely used as a serum marker for the diagnosis of prostate cancer. To evaluate two anti-free PSA monoclonal antibodies (mAbs) as potential tools in new generations of more relevant PSA assays, we report here their properties towards the recognition of specific forms of free PSA in seminal fluids, LNCaP supernatants, 'non-binding' PSA and sera from cancer patients. PSA from these different origins was immunopurified by the two anti-free PSA mAbs (5D3D11 and 6C8D8) as well as by an anti-total PSA mAb. The composition of the different immunopurified PSA fractions was analysed and their respective enzymatic activities were determined. In seminal fluid, enzymatically active PSA was equally purified with the three mAbs. In LNCaP supernatants and human sera, 5D3D11 immunopurified active PSA mainly, whereas 6C8D8 immunopurified PSA with residual activity. In sera of prostate cancer patients, we identified the presence of a mature inactive PSA form which can be activated into active PSA by use of high saline concentration or capture by an anti-total PSA mAb capable of enhancing PSA activity. According to PSA models built by comparative modelling with the crystal structure of horse prostate kallikrein described previously, we assume that active and activable PSA could correspond to mature intact PSA with open and closed conformations of the kallikrein loop. The specificity of 5D3D11 was restricted to both active and activable PSA, whereas 6C8D8 recognized all free PSA including intact PSA, proforms and internally cleaved PSA.Prostate-specific antigen (PSA) is widely used as a serum marker for the diagnosis of prostate cancer. To evaluate two anti-free PSA monoclonal antibodies (mAbs) as potential tools in new generations of more relevant PSA assays, we report here their properties towards the recognition of specific forms of free PSA in seminal fluids, LNCaP supernatants, 'non-binding' PSA and sera from cancer patients. PSA from these different origins was immunopurified by the two anti-free PSA mAbs (5D3D11 and 6C8D8) as well as by an anti-total PSA mAb. The composition of the different immunopurified PSA fractions was analysed and their respective enzymatic activities were determined. In seminal fluid, enzymatically active PSA was equally purified with the three mAbs. In LNCaP supernatants and human sera, 5D3D11 immunopurified active PSA mainly, whereas 6C8D8 immunopurified PSA with residual activity. In sera of prostate cancer patients, we identified the presence of a mature inactive PSA form which can be activated into active PSA by use of high saline concentration or capture by an anti-total PSA mAb capable of enhancing PSA activity. According to PSA models built by comparative modelling with the crystal structure of horse prostate kallikrein described previously, we assume that active and activable PSA could correspond to mature intact PSA with open and closed conformations of the kallikrein loop. The specificity of 5D3D11 was restricted to both active and activable PSA, whereas 6C8D8 recognized all free PSA including intact PSA, proforms and internally cleaved PSA.

Prostate-specific antigen (PSA) is an important marker for the diagnosis and management of prostate cancer. Free PSA has been shown to be more extensively cleaved in sera from benign prostatic hyperplasia patients than in sera from prostate cancer patients. Moreover, the presence of enzymatically activatable PSA was characterized previously in sera from patients with prostate cancer by the use of the specific anti-free PSA monoclonal antibody (mAb) 5D3D11. As an attempt to obtain ligands for the specific recognition of different PSA forms including active PSA, phage-displayed linear and cyclic peptide libraries were screened with PSA coated directly into microplate wells or presented by two different anti-total PSA mAbs. Four different phage clones were selected for their ability to recognize PSA and the inserted peptides were produced as synthetic peptides. These peptides were found to capture and to detect specifically free PSA, even in complex biological media such as sera or tumour cell culture supernatants. Alanine scanning of peptide sequences showed the involvement of aromatic and hydrophobic residues in the interaction of the peptides with PSA whereas Spotscan analysis of overlapping peptides covering the PSA sequence identified a peptide binding to the kallikrein loop at residues 82-87, suggesting that the peptides could recognize a non-clipped form of PSA. Moreover, the PSA-specific peptides enhance the enzymatic activity of PSA immobilized into microplate wells whereas the capture of PSA by the peptides inhibited totally its enzymatic activity while the peptide binding to PSA had no effect in solution. These PSA-specific peptides could be potential tools for the recognition of PSA forms more specifically associated to prostate cancer.Prostate-specific antigen (PSA) is an important marker for the diagnosis and management of prostate cancer. Free PSA has been shown to be more extensively cleaved in sera from benign prostatic hyperplasia patients than in sera from prostate cancer patients. Moreover, the presence of enzymatically activatable PSA was characterized previously in sera from patients with prostate cancer by the use of the specific anti-free PSA monoclonal antibody (mAb) 5D3D11. As an attempt to obtain ligands for the specific recognition of different PSA forms including active PSA, phage-displayed linear and cyclic peptide libraries were screened with PSA coated directly into microplate wells or presented by two different anti-total PSA mAbs. Four different phage clones were selected for their ability to recognize PSA and the inserted peptides were produced as synthetic peptides. These peptides were found to capture and to detect specifically free PSA, even in complex biological media such as sera or tumour cell culture supernatants. Alanine scanning of peptide sequences showed the involvement of aromatic and hydrophobic residues in the interaction of the peptides with PSA whereas Spotscan analysis of overlapping peptides covering the PSA sequence identified a peptide binding to the kallikrein loop at residues 82-87, suggesting that the peptides could recognize a non-clipped form of PSA. Moreover, the PSA-specific peptides enhance the enzymatic activity of PSA immobilized into microplate wells whereas the capture of PSA by the peptides inhibited totally its enzymatic activity while the peptide binding to PSA had no effect in solution. These PSA-specific peptides could be potential tools for the recognition of PSA forms more specifically associated to prostate cancer.

Small and medium-sized enterprises (SMEs) are a reality in the production organization of all contemporary economies. Their agglomeration, the nature, quality and intensity of interactions between them and with their environment are a source of positive proximity externalities and competitive advantage. These externalities structure and energize production systems. The economy of proximity and the new geographical economy present models of local economic dynamics driven by agglomerations of SMEs. These are local production systems (LPS) whose variants are explained by entrepreneurial logics and modes of productive organization. Few studies have focused on LPS in developing countries.Based on the case of the Bobo Dioulasso district of Burkina Faso, this thesis starts from the observation of insufficient economic activity despite the availability of agricultural and construction resources and the existence of an agglomeration of cotton seed crushing SMEs. It proposes to understand this situation, which is not in conformity with the theses of the SPLs, by identifying and characterizing the productive organization of this agglomeration of SMEs. In addition to this identification, this thesis highlights the factors of a recomposition of the cotton seed crushing system in Bobo Dioulasso more competitive and generating economic dynamics and local development.To this end, we used an inductive approach of a qualitative nature based on the examination and interpretation of non-numerical phenomena to discover the underlying explanations for their action. An exploratory work of the economic theory around this model, allowed us first of all to elaborate a theoretical analysis grid of the determinants of the dynamics of this model at three levels: the performance of the SME related to its internal capacity of organization, the competitiveness of the SME agglomeration related to the nature, the quality and the intensity of the interactions between the SMEs and finally the influence of the environment of the agglomeration on the latter through services, markets and public action. This theoretical grid was then confronted with the study area of the thesis. To reveal the internal dynamics of the study area, three sources of information were mobilized: previous work, administrative data and survey data. The empirical part of the research is based on a specific type of LPS, namely the Italian industrial district. With the help of an AFCM, we identified the determinants of the dynamics of the SME agglomeration in the study area and on the basis of the CAH of the data, we elaborated four classes of SMEs that reflect as many entrepreneurial logics of the study area. By comparing the theoretical determinants of the analysis grid with the empirical determinants from the SME survey, we identified the productive organization mode of the study zone.According to the analysis, the mode of productive organization of this SME agglomeration was qualified as a satellite industrial district in a "transitory" and "unfinished" form of the (classic) Marshallian model with a progression march towards the industrial district radiating around the large cotton seed crushing companies. The conditions for the emergence of this industrial district are discussed.They are based on two pillars, namely the adoption of reforms aimed at improving the SME environment and the development of functional relations between SMEs, large enterprises and VSEs in a logic of production arrangement.; Les petites et moyennes entreprises (PME) sont une réalité de l’organisation de la production de toutes les économies contemporaines. Leur agglomération, la nature, la qualité et l’intensité des interactions entre elles et avec leur environnement sont une source d’externalités de proximité positives et d’avantage compétitif. Ces externalités structurent et dynamisent les systèmes de production. L’économie de la proximité et la nouvelle économie géographique présentent des modèles de dynamique économique locale portée par des agglomérations de PME. Il s’agit des systèmes productifs locaux (SPL) dont les variantes sont expliquées par les logiques entrepreneuriales et les modes d’organisation productive. Peu de travaux s’intéressent aux SPL des pays en développement. A partir du cas burkinabé du district de Bobo Dioulasso, cette thèse part du constat d’une activité économique insuffisante malgré la disponibilité de ressources agricoles et construites et l’existence d’une agglomération de PME de trituration des graines de coton. Elle se propose de comprendre cette situation non conforme aux thèses des SPL par l’identification et la caractérisation du mode d’organisation productive de cette agglomération de PME. En sus de cette identification, cette thèse fait ressortir les facteurs d’une recomposition du système de trituration des graines de coton à Bobo Dioulasso plus compétitif et générateur de dynamique économique et de de développement local. A cette fin, nous avons utilisé une démarche inductive de nature qualitative qui repose sur l’examen et l’interprétation de phénomènes non numériques pour découvrir les explications sous-jacentes de leur action. Un travail exploratoire de la théorie économique autour de ce modèle, nous a tout d’abord permis d’élaborer une grille d’analyse théorique des déterminants de la dynamique de ce modèle à trois niveaux : la performance de la PME relevant de sa capacité interne d’organisation, la compétitivité de l’agglomération de PME portant sur la nature, la qualité et l’intensité des interactions entre les PME et enfin l’influence de l’environnement de l’agglomération sur cette dernière à travers les services, les marchés et l’action publique. Cette grille théorique a été ensuite confrontée à la zone d’étude de la thèse. Pour révéler les dynamiques internes de la zone d’étude, trois sources d’informations ont été mobilisées : des travaux antérieurs, des données administratives et des données d’enquêtes. La partie empirique de la recherche se base sur un type précis de SPL, à savoir le district industriel italien. A l’aide d’une AFCM, nous avons identifié les déterminants de la dynamique de l’agglomération des PME de la zone d’étude et sur la base de la CAH des données, nous avons élaboré quatre classes de PME qui traduisent autant de logiques entrepreneuriales de la zone d’étude. Par rapprochement des déterminants théorique de la grille d’analyse et des déterminants empiriques issues de l’enquête auprès des PME, nous avons identifié le mode d’organisation productive de la zone d’étude. Aux termes de l’analyse, le mode d’organisation productive de cette agglomération de PME a été qualifié de district industriel satellitaire dans une forme « transitoire » et « inachevée » du modèle marshallien (classique) avec une marche de progression vers le district industriel rayonnant autour des grandes entreprises de trituration des graines de coton. Les conditions d’émergence de ce district industriel sont discutées. Elles reposent sur deux piliers à savoir l’adoption des réformes visant l’amélioration de l’environnement des PME et le développement des relations fonctionnelles entre les PME, les grandes entreprises et les TPE dans une logique d’arrangement de la production.

Demo-economic transitions in sub-Saharan Africa have led to an unprecedented increase in population, calling into question the capacity of current economic structures to ensure people’s livelihoods, as well as the reproduction of these livelihoods that allows societies to endure over time. In a globalized world facing climate change, this situation brings the debates about structural change patterns able to support demo-economic transitions in sub-Saharan Africa back to the forefront. Among these patterns, this PhD chooses to explore the rural and agricultural pattern. In order to inform this option pattern, the PhD has a specific approach that considers structural change as the evolution of socioeconomic reproduction patterns of rural African households.The originality of the approach taken by this PhD when analyzing this research subject lies in its combination of an institutional approach with a comparative and historical methodology, that examines socioeconomic transition among rural youth over a number of generations, thus enabling a long-term view. These transitions were built from the collection of original biographical data from 525 households in four rural areas in Senegal and Zambia.After the elaboration of a theoretical model in institutional economics, the PhD produces a typology of rural youth socioeconomic transitions from which generational changes in the modalities of youth transitions are identified. Linking these changes to the institutional framework of each generation of individuals leads to the identification of key institutions that determine socioeconomic reproduction patterns of rural households according to different contexts in rural Africa. Next, the PhD identifies the dependency relationship between the family farming model and the way generations of rural youth enter farming as a means of becoming economically active. The PhD states that the family farming model, historical pattern of socioeconomic reproduction of rural households, is constantly being reconfigured to continue to support youth transition. This reconfiguration requires institutional adjustments in the relation to capital and knowledge, but it entails a deeper institutional crisis regarding access to land and collective welfare systems and that suggest the definition of new regulation mechanisms involving different levels of political authority. The mechanisms are one the essential conditions for the transformation of rural economies so that they can support the demo-economic transitions of sub-Saharan African countries.; Dans les pays d’Afrique subsaharienne, la transition démo-économique se traduit par une croissance de la population inégalée à l’échelle historique ce qui questionne la capacité des cadres de production actuels à assurer les moyens d’existence des populations, ainsi que leur renouvellement qui permet aux sociétés de perdurer dans le temps. Dans un monde globalisé devant faire face au changement climatique et à ses conséquences environnementales, cette situation remet au goût du jour les débats sur les modalités du changement structurel qui supporteront les transitions démo-économiques des pays d’Afrique subsaharienne. Parmi ces modalités, cette thèse fait le choix d’explorer la trajectoire rurale et agricole. Pour renseigner les conditions de réalisation de cette trajectoire, la thèse adopte une approche singulière qui considère le changement structurel comme celui de l’évolution, dans le temps long, des modalités de la reproduction socio-économique des ménages ruraux.Pour étudier cet objet, l’originalité de la thèse est d’articuler une approche institutionnaliste du changement structurel avec une méthodologie comparative et historique qui utilise les trajectoires d’insertion socio-économique d’une succession de générations de jeunes ruraux pour représenter le temps long. Ces trajectoires ont été reconstituées à partir de données biographiques originales collectées dans quatre zones rurales du Sénégal et de la Zambie auprès de 525 ménages.Après avoir élaboré un modèle théorique institutionnaliste, la thèse produit tout d’abord une typologie des trajectoires d’activité et de mobilité des jeunes ruraux à partir de laquelle sont identifiés des changements d’ordre générationnel dans les modalités d’insertion des jeunes. La mise en relation de ces changements avec le cadre institutionnel dans lequel chaque génération s’insère aboutit à l’identification des institutions déterminantes des modalités de reproduction socio-économique des ménages ruraux en fonction de différentes situations agricoles et socio-économiques en Afrique rurale. Ensuite, la thèse identifie les relations de dépendance entre le modèle agricole familial et la manière dont les générations successives de jeunes ruraux mobilisent l’activité agricole pour s’insérer dans le système productif. La thèse affirme que le modèle agricole familial, modalité historique de la reproduction des ménages ruraux caractérisé par des liens organiques entre la famille et l’unité de production, se recompose sans cesse pour continuer à être le support de l’insertion des jeunes ruraux. Cette recomposition passe par des ajustements institutionnels dans la relation au capital et au savoir des jeunes mais implique une crise plus profonde des institutions sur l’accès à la terre et les modalités de la prévoyance collective ce qui suggère la recherche de nouveaux mécanismes de régulation impliquant différents niveaux d’autorité politique. Ces nouveaux mécanismes sont une des conditions indispensables de la transformation des économies rurales pour qu’elles puissent supporter les transitions démo-économiques des pays d’Afrique subsaharienne.

Demo-economic transitions in sub-Saharan Africa have led to an unprecedented increase in population, calling into question the capacity of current economic structures to ensure people’s livelihoods, as well as the reproduction of these livelihoods that allows societies to endure over time. In a globalized world facing climate change, this situation brings the debates about structural change patterns able to support demo-economic transitions in sub-Saharan Africa back to the forefront. Among these patterns, this PhD chooses to explore the rural and agricultural pattern. In order to inform this option pattern, the PhD has a specific approach that considers structural change as the evolution of socioeconomic reproduction patterns of rural African households.The originality of the approach taken by this PhD when analyzing this research subject lies in its combination of an institutional approach with a comparative and historical methodology, that examines socioeconomic transition among rural youth over a number of generations, thus enabling a long-term view. These transitions were built from the collection of original biographical data from 525 households in four rural areas in Senegal and Zambia.After the elaboration of a theoretical model in institutional economics, the PhD produces a typology of rural youth socioeconomic transitions from which generational changes in the modalities of youth transitions are identified. Linking these changes to the institutional framework of each generation of individuals leads to the identification of key institutions that determine socioeconomic reproduction patterns of rural households according to different contexts in rural Africa. Next, the PhD identifies the dependency relationship between the family farming model and the way generations of rural youth enter farming as a means of becoming economically active. The PhD states that the family farming model, historical pattern of socioeconomic reproduction of rural households, is constantly being reconfigured to continue to support youth transition. This reconfiguration requires institutional adjustments in the relation to capital and knowledge, but it entails a deeper institutional crisis regarding access to land and collective welfare systems and that suggest the definition of new regulation mechanisms involving different levels of political authority. The mechanisms are one the essential conditions for the transformation of rural economies so that they can support the demo-economic transitions of sub-Saharan African countries.; Dans les pays d’Afrique subsaharienne, la transition démo-économique se traduit par une croissance de la population inégalée à l’échelle historique ce qui questionne la capacité des cadres de production actuels à assurer les moyens d’existence des populations, ainsi que leur renouvellement qui permet aux sociétés de perdurer dans le temps. Dans un monde globalisé devant faire face au changement climatique et à ses conséquences environnementales, cette situation remet au goût du jour les débats sur les modalités du changement structurel qui supporteront les transitions démo-économiques des pays d’Afrique subsaharienne. Parmi ces modalités, cette thèse fait le choix d’explorer la trajectoire rurale et agricole. Pour renseigner les conditions de réalisation de cette trajectoire, la thèse adopte une approche singulière qui considère le changement structurel comme celui de l’évolution, dans le temps long, des modalités de la reproduction socio-économique des ménages ruraux.Pour étudier cet objet, l’originalité de la thèse est d’articuler une approche institutionnaliste du changement structurel avec une méthodologie comparative et historique qui utilise les trajectoires d’insertion socio-économique d’une succession de générations de jeunes ruraux pour représenter le temps long. Ces trajectoires ont été reconstituées à partir de données biographiques originales collectées dans quatre zones rurales du Sénégal et de la Zambie auprès de 525 ménages.Après avoir élaboré un modèle théorique institutionnaliste, la thèse produit tout d’abord une typologie des trajectoires d’activité et de mobilité des jeunes ruraux à partir de laquelle sont identifiés des changements d’ordre générationnel dans les modalités d’insertion des jeunes. La mise en relation de ces changements avec le cadre institutionnel dans lequel chaque génération s’insère aboutit à l’identification des institutions déterminantes des modalités de reproduction socio-économique des ménages ruraux en fonction de différentes situations agricoles et socio-économiques en Afrique rurale. Ensuite, la thèse identifie les relations de dépendance entre le modèle agricole familial et la manière dont les générations successives de jeunes ruraux mobilisent l’activité agricole pour s’insérer dans le système productif. La thèse affirme que le modèle agricole familial, modalité historique de la reproduction des ménages ruraux caractérisé par des liens organiques entre la famille et l’unité de production, se recompose sans cesse pour continuer à être le support de l’insertion des jeunes ruraux. Cette recomposition passe par des ajustements institutionnels dans la relation au capital et au savoir des jeunes mais implique une crise plus profonde des institutions sur l’accès à la terre et les modalités de la prévoyance collective ce qui suggère la recherche de nouveaux mécanismes de régulation impliquant différents niveaux d’autorité politique. Ces nouveaux mécanismes sont une des conditions indispensables de la transformation des économies rurales pour qu’elles puissent supporter les transitions démo-économiques des pays d’Afrique subsaharienne.

Demo-economic transitions in sub-Saharan Africa have led to an unprecedented increase in population, calling into question the capacity of current economic structures to ensure people’s livelihoods, as well as the reproduction of these livelihoods that allows societies to endure over time. In a globalized world facing climate change, this situation brings the debates about structural change patterns able to support demo-economic transitions in sub-Saharan Africa back to the forefront. Among these patterns, this PhD chooses to explore the rural and agricultural pattern. In order to inform this option pattern, the PhD has a specific approach that considers structural change as the evolution of socioeconomic reproduction patterns of rural African households.The originality of the approach taken by this PhD when analyzing this research subject lies in its combination of an institutional approach with a comparative and historical methodology, that examines socioeconomic transition among rural youth over a number of generations, thus enabling a long-term view. These transitions were built from the collection of original biographical data from 525 households in four rural areas in Senegal and Zambia.After the elaboration of a theoretical model in institutional economics, the PhD produces a typology of rural youth socioeconomic transitions from which generational changes in the modalities of youth transitions are identified. Linking these changes to the institutional framework of each generation of individuals leads to the identification of key institutions that determine socioeconomic reproduction patterns of rural households according to different contexts in rural Africa. Next, the PhD identifies the dependency relationship between the family farming model and the way generations of rural youth enter farming as a means of becoming economically active. The PhD states that the family farming model, historical pattern of socioeconomic reproduction of rural households, is constantly being reconfigured to continue to support youth transition. This reconfiguration requires institutional adjustments in the relation to capital and knowledge, but it entails a deeper institutional crisis regarding access to land and collective welfare systems and that suggest the definition of new regulation mechanisms involving different levels of political authority. The mechanisms are one the essential conditions for the transformation of rural economies so that they can support the demo-economic transitions of sub-Saharan African countries.; Dans les pays d’Afrique subsaharienne, la transition démo-économique se traduit par une croissance de la population inégalée à l’échelle historique ce qui questionne la capacité des cadres de production actuels à assurer les moyens d’existence des populations, ainsi que leur renouvellement qui permet aux sociétés de perdurer dans le temps. Dans un monde globalisé devant faire face au changement climatique et à ses conséquences environnementales, cette situation remet au goût du jour les débats sur les modalités du changement structurel qui supporteront les transitions démo-économiques des pays d’Afrique subsaharienne. Parmi ces modalités, cette thèse fait le choix d’explorer la trajectoire rurale et agricole. Pour renseigner les conditions de réalisation de cette trajectoire, la thèse adopte une approche singulière qui considère le changement structurel comme celui de l’évolution, dans le temps long, des modalités de la reproduction socio-économique des ménages ruraux.Pour étudier cet objet, l’originalité de la thèse est d’articuler une approche institutionnaliste du changement structurel avec une méthodologie comparative et historique qui utilise les trajectoires d’insertion socio-économique d’une succession de générations de jeunes ruraux pour représenter le temps long. Ces trajectoires ont été reconstituées à partir de données biographiques originales collectées dans quatre zones rurales du Sénégal et de la Zambie auprès de 525 ménages.Après avoir élaboré un modèle théorique institutionnaliste, la thèse produit tout d’abord une typologie des trajectoires d’activité et de mobilité des jeunes ruraux à partir de laquelle sont identifiés des changements d’ordre générationnel dans les modalités d’insertion des jeunes. La mise en relation de ces changements avec le cadre institutionnel dans lequel chaque génération s’insère aboutit à l’identification des institutions déterminantes des modalités de reproduction socio-économique des ménages ruraux en fonction de différentes situations agricoles et socio-économiques en Afrique rurale. Ensuite, la thèse identifie les relations de dépendance entre le modèle agricole familial et la manière dont les générations successives de jeunes ruraux mobilisent l’activité agricole pour s’insérer dans le système productif. La thèse affirme que le modèle agricole familial, modalité historique de la reproduction des ménages ruraux caractérisé par des liens organiques entre la famille et l’unité de production, se recompose sans cesse pour continuer à être le support de l’insertion des jeunes ruraux. Cette recomposition passe par des ajustements institutionnels dans la relation au capital et au savoir des jeunes mais implique une crise plus profonde des institutions sur l’accès à la terre et les modalités de la prévoyance collective ce qui suggère la recherche de nouveaux mécanismes de régulation impliquant différents niveaux d’autorité politique. Ces nouveaux mécanismes sont une des conditions indispensables de la transformation des économies rurales pour qu’elles puissent supporter les transitions démo-économiques des pays d’Afrique subsaharienne.

Energy demand in Sub-Saharan Africa has outpaced that in the North. The International Energy Agency (IEA) has forecasted the greatest increase in energy consumption to come from this area. The relationship between energy consumption and economic growth began to be studied in Sub-Saharan Africa in the late 90s, using the same method as for developed countries and with the same lack of consensus on the direction of causality. This thesis attempts to clarify this situation through a meta-analysis of fifty articles published since 1996 to 2016. This meta-analysis involves five analytical categories: type of publication, geographical area studied, econometrics method used, energy consumption indicators, and control variables. Each of these dimensions includes many disaggregated variables. Logistic regressions are run on the variables presented above for each of the four causality hypotheses. In research that studies single countries, the likelihood of finding for a given causality hypothesis is very sensitive to the econometric method implemented. Findings on a panel of countries are then presented; their methods assert the neutrality hypothesis.The energy sector in sub-Saharan Africa is in a state of flux. Based on an approach borrowed from industrial economics, using historical examples that point to three successive transformations of electricity market structure, our analysis differs from previous studies by looking at demand as a consequence of supply. Our results show, an extremely fragmented demand for energy in sub-Saharan African countries,within which a very dynamic unmet demand drives change in how supply is offered. New forms of energy provisioning introduced on the electricity market put into question the initial on-grid network model. The appearance of decentralized electricity production shows that there is a potential for going beyond current limitations and moving away from a supply structure focused on the maintenance and improvement of ongrid networks without consideration of the needs of rural populations on one hand, and on the other hand, the establishment of expensive mini-grids that provide inferior energy services to rural populations. New territorial linkages focus on mechanisms seen in energy demand.As a result, our doctoral research questions the energy access gap between urban and rural populations, that remains considerable, even considering households and businesses with potential access to the grid. Tariff schedules are thus the interface between the conditions for producing electricity, the end user and public energy-access policy. This article evaluates the contribution of electricity tariff schedules, a major access instrument, to the continued existence of the energy access gap, and looks at whether this gap is primarily between rural and urban populations. Using a panel set of random effects that are double controlled (1990-2012, 33 countries divided into 4 groups, 17 variables related to residential and commercial consumption, production and willingness to pay), the article shows the systematically regressive effect of tariff schedules on access for both residential and commercial consumption, their failure to provide reduced rates to enable access to the poor, their neglect of households passing the threshold of the first consumption block and their ineffective treatment of energy poverty in urban and rural households. For households with access to a centralised grid, we find that the criterion of location is less important than the economic conditions of the customers served., Notre thèse précise la nature de la relation entre la consommation énergétique et la croissance économique, cette dernière étant analysée à l’échelle des pays de l’Afrique Sub-Saharienne. Premièrement, nous réalisons une revue quantitative synthétisée de la relation entre la consommation d’énergie et la croissance économique pour les pays de l’Afrique Sub-Saharienne. La méta-analyse référence ainsi 50 travaux scientifiques publiés entre les années 1996 (date de la première publication) et 2016.Partant du résultat qu’aucun lien clair n’a été établi au niveau des variables influençant la relation énergie-croissance, la thèse s’oriente vers les fortes disparités régionales à l’œuvre en termes d’offre et demande par une analyse des mutations observées au niveau de ces deux variables des années 1950 à de nos jours. Précisément, nous analysons les dynamiques relatives à la demande, faisant de celle-ci une cause de l’offre et non l’inverse. Ces dynamiques permettent d’envisager de nouveaux design en termes de politiques énergétiques tout en dépassant les limites inhérentes au modèle passé à savoir une offre tournée, d’une part, vers le maintien et l’amélioration des réseaux on-grid sans réponse aux besoins des populations rurales et, d’autre part, vers les mini grids en faveur des populations rurales coûteux et procurant de faibles services énergétiques. Les technologies de production décentralisées restent toutefois coûteuses pour les populations, la soutenabilité économique restant aux solutions centralisées (on-grid).De ce fait, notre recherche doctorale s’interroge sur des tarifications spécifiques pouvant être mises en vigueur dont le but serait l’augmentation des revenus des ruraux, notamment issus des activités productives, ce qui garantiraient en retour le déploiement de l’électrification. Cette contribution se veut être un parallèle entre les instruments tarifaires développés par les compagnies d’électricité en ASS les dynamiques du non-accès à l’électricité, analysé au regard des ménages urbains et ruraux connectés au réseau on-grid. Nous montrons que le non-accès à l’électricité reste entretenu par la régressivité de la tarification on-grid mise en place et qu’elle profite davantage à certaines activités productives. Nous mettons en exergue les les limites inhérentes à l’accès, d’où ressortent que les conditions économiques des populations et en particulier leur niveau de pauvreté, bien plus que leur localisation.