Changing Patterns of Solidarity in Kinshasa

Ethnic based solidarity systems facilitated the integration of rural migrants into the intricacies of «modem» urban life throughout much of Africa. Now that these cities have become increasingly ungoverned and ungovernable, new forms of solidarity systems have emerged. The multiform crisis in Kinshasa, sub-Saharan Africa's second largest city, is as legendary as the survival strategies invented by the Congo capital's residents. These systems, historically complex, are increasingly characterised by pragmatism. Despite the marked rise of individualism needed to «fend for oneself», without recourse to solidarity networks, the situation of Kinois would be even more precarious than it is today. This article documents these dynamic forms of social organisation, their origins and evolution and the local and international political context that has contributed to their perpetual re-invention.Os sistemas de solidariedade baseados na etnicidade favoreceram a integração dos migrantes rurais no emaranhado da vida modema em muitas cidades africanas. Na medida em que estas cidades sao cada vez menos govemadas e govemaveis, regista-se a emergencia de novos sistemas de solidariedade que representam a ordem na desordem. Em Kinshasa, a segunda cidade ao Sui do Saara, a crise multifacetada e tao lendciria como as estrategias de sobrevivencia imaginadas pelos que nela residem. Historicamente complexos, estes sistemas caracterizam-se cada vez mais pela necessidade de as pessoas serem pragmaticas: ninguem pode doravante dar-se ao luxo de partilhar sem a esperança de algum retorno. Apesar do individualismo que dai resulta, as multiplas redes de solidariedade sao indispensaveis, porque sem elas a situação dois «kinois» seria ainda mais dramática. O presente artigo procura descrever esta forma dinfunica de organizaçao social, as suas origens e a sua evolução num contexto politico local e intemacional que contribui para a sua re-invenção permanente.Les systèmes de solidarité basés sur l'ethnicité ont favorisé I’intégration des migrants ruraux dans les dédales de la vie moderne dans beaucoup de villes africaines. Au fur et à mesure que ces villes deviennent de plus en plus ingouvernées et ingouvernables, on assiste à l'émergence de nouveaux systèmes de solidarité qui représentent l'ordre dans le désordre. A Kinshasa, deuxième ville au sud du Sahara, la crise multiforme est aussi légendaire que les stratégies de survie mises en place par ses résidants. Historiquement complexes, ces systèmes se caractérisent de plus en plus par le besoin d'être pragmatique - on ne peut plus se permettre de partager sans l'espoir d'un retour. Malgré la tendance individualiste qui en résulte, les multiples réseaux de solidarité sont indispensables, car sans eux la situation des kinois serait encore plus dramatique qu'elle ne l'est aujourd'hui. Cet article vise à faire connaitre cette forme dynamique d'organisation sociale, ses origines, son évolution et le contexte politique local et international qui contribuent à sa perpétuelle ré-invention

Wpływ domieszkowania na zależności temperaturowe dyfuzyjności cieplnej monokryształów YAG, YVO4 i GdCOB

The aim of this thesis entitled “Influence o f doping on thermal diffusivity dependence on temperature of single crystals of YAG, YVOj i GdCOB’’ was to determine the thermal diffusivity of YAG, YVC>4, and GdCOB single crystals as a function of temperature, and to investigate an influence of dopants on these dependencies. To realize this purpose new experimental setup for the determination of thermal diffusivity dependence on temperature of transparent samples was built. The study was carried out for crystals which belong to different crystal systems: the yttrium aluminum garnet (YAG) having cubic structure, yttrium orthovanadate (YV04) of tetragonal structure and gadolinium calcium oxoborate (GdCOB) crystallizing in the monoclinic structure. The crystals were doped with calcium ions, rare earth ions such as ytterbium, neodymium, thulium, and transition metal vanadium. The influence of doping and temperature in rangę from 30 °C to 300 °C on the thermal diffusivity was analyzed. An anisotropy of thermal conductivity of investigated samples was also taken into account. Obtained results confirmed, that the influence of doping on the thermal diffusivity of investigated materials strongly depends on temperature. The thermal diffusivity of all investigated samples decreases with increasing of sample temperature from 30 °C to 300 °C, but the drop in the thermal diffusivity is the highest for pure single crystals. The introduction of dopant ions into a crystal lattice leads to a significant reduction in the thermal diffusivity at lower temperatures in comparison with pure crystals. However, the influence of dopants becomes less pronounced with increasing temperature, and in the case o f weakly doped crystals it becomes negligible at higher temperatures. The interpretation of obtained thermal diffusivity dependence on temperature for pure and doped single crystals was based on the Debye model of lattice thermal conductivity of solids. It was assumed that the decrease in thermal diffusivity with temperature and increasing concentration of impurities is caused by shortening of the phonons mean free path due to phonon-phonon and phonon-point defect scatterings. Dopant ions create additional phonon scattering centers which cause a drop of thermal diffusivity of doped crystals in comparison with pure ones. At the same time an increase of crystal temperature lowers the thermal diffusivity because of increasing freąuency of phonon-phonon scattering. This mechanism at higher temperatures prevails on phonon scattering on dopants, what is evident in the measured thermal diffusivity dependency on temperature for the doped crystals. All the aims and scopes of this thesis have been completed, the results presented at conferences, and published in international journals

L’économie politique de la filière du charbon de bois à Kinshasa et à Lubumbashi

Charcoal use in urban Congo expanded significantly in the early 1990s. While recourse to charcoal (makala) as cooking fuel existed during the early independence period, most urban households had access to electricity for domestic use. Population, pressure, poorly maintained infrastructures and state crisis combined to force people to rely on makala for their daily cooking needs. Trade networks developed to make the link between makala producers and consumers. This can be considered as a popular response to state failure and is the subject of this working paper. Our research followed the trade network that includes charcoal producers, transporters, middlemen, wholesalers and retailers and a host of other peripheral supporting actors who claim to „live miraculously? from the network. The main conclusion of the research is that this informal trade network thrives, despite hassles from state agents, because it provides a vital service to Congo's urban poor.

La Gestion des Ressources Naturelles dans les Zones Périurbaines d’Afrique Centrale : une approche privilégiant les parties prenantes

O presente artigo apresenta o quadro conceptual e os primeiros resultados de um es­tudo em curso sobre processos de gestão de recursos naturais, em espaços peri-urbanos da África Central. Com base em dados etnográficos das realidades empíricas de Kinshasa e Lubumbashi (República Democrática do Congo) e de Brazzaville (República do Congo), o texto analisa sobretudo os conceitos de «governação ambiental» e de «espaço peri-urbano», partindo das lógicas dos próprios protagonistas envolvidos na gestão dos re­cursos naturais. Deste modo, são exploradas as ambiguidades, ambivalências, relações de poder e tensões sociais geradas ou sustentadas por certas peculiaridades dos jogos de poder que envolvem os diferentes actores sociais considerados.The article presents a conceptual framework and the first results of an ongoing research on processes of natural resources management in peri-urban areas of Central Africa. Based on ethnographic data from the empirical realities of Kinshasa and Lubumbashi (Democratic Republic of Congo) and of Brazzaville (Republic of Congo), the text analyses especially the concepts of «environmental governance» and «peri-urban spaces», based on the logics of the very protagonists involved in the natural resources management. This way, the text explores the ambiguities, ambivalences, power relations and social tensions generated or sustained by certain peculiarities of the power strategies in which these social actors are involved

Introduction

Véritable paradigme d’une Afrique confrontée aux affres de la guerre, au délitement de l’Etat et à l’informalisation économique, le Congo cumule apparemment tous les obstacles à la conduite de recherches de terrain répondant aux canons méthodologiques des différentes disciplines. Depuis le renouveau de la réflexion épistémologique des années 1980 – qu’illustre bien l’ouvrage de Clifford et Marcus (1986) – les démarches de recherche font l’objet d’une vigilance critique nettement plus approfon..

Burying the hatchet? Britain and France in the Democratic Republic of Congo

Against the background of conflict in the Great Lakes Region, the UK and France promised, at their 1998 Saint-Malo summit, to set aside rivalries and cooperate on Africa. In subsequent Anglo-French gatherings, they singled out the DRC and pledged to work together there to promote peace and tackle poverty. This article asks whether this coordination took place and whether it involved a ‘deconflictualisation’ of approaches, ‘coincidental’ cooperation, or ‘sustained and reciprocal’ collaboration. It looks for evidence of institutionalisation of UK-French ties and policy cooperation in the fields of peacebuilding and poverty reduction. It then identifies the pressures for, and barriers to, collaboration, focusing particularly on the role of interests, foreign policy norms, institutional factors and resource constraints. It concludes by setting out the wider implications of UK-French cooperation and the limited prospects of closer future collaboration

Thermal diffusivity, effusivity and conductivity of CdMnTe mixed crystals

Cd1-xMnxTe mixed crystals belong to a class of materials called ‘‘semimagnetic semiconductor’’ or diluted magnetic semiconductor (DMS) with addition of magnetic ions like Mn2+ implemented into crystal structure. The crystals under investigation were grown from the melt by the high pressure high temperature modified Bridgman method in the range of composition 0 < x < 0.7. Thermal properties of these compounds have been investigated by means of photopyroelectric (PPE) calorimetry in both, back and front detection configuration. The values of the thermal diffusivity and effusivity were derived from experimental data. Thermal conductivity of the specimens was calculated from the simple theoretical dependencies between thermal parameters. The influence of Mn concentration on thermal properties of Cd1-xMnxTe crystals have been presented and discussed