Assainir la ville diffuse : l'impossible contrôle de l'urbanisation par les réseaux

L'aménagement durable du territoire impose de composer avec la densification de l'habitat et à lutter contre les pollutions domestiques. Depuis la loi sur l'eau de 1992, les politiques d'assainissement permettent de réunir ces objectifs en créant des outils transversaux sur le plan de la gestion de l'occupation des sols et du contrôle des permis de construire. Mais ces politiques d'assainissement, qui peuvent être considérées comme un moyen d'obliger l'urbanisation à se concentrer autour d'un réseau principal, n'atteignent pas leurs objec- tifs. Une analyse des dynamiques métropolitaines montre que la diffusion de l'habitat se poursuit, en s'appuyant sur la présence d'installations individuelles d'assainissement non collectif légitimées par les nouvelles mesures de contrôle. Au niveau local, l'étude des jeux d'acteurs explique plus en détails ces processus, en appréhendant notamment les techniques de contournement des outils de production de la ville dense

Le périurbain, théâtre d'innovations. Les pratiques professionnelles dans le domaine de l'assainissement individuel

En étudiant les pratiques professionnelles dans le domaine de l'assainissement individuel des eaux usées, l'article illustre la complexité des problèmes liés à la périurbanisation. Dans la lignée des réflexions sur la vitalité du périurbain, il montre comment ces territoires peuvent être un terreau d'innovations dans le domaine de l'aménagement et de l'urbanisme

Connecter la ville numérique au territoire : l’apport des sciences sociales

International audienc

L'aménagement durable et la quête de la pluridisciplinarité : urbanisme et assainissement individuel en Provence

Cette recherche étudie les liens entre la gestion de l'assainissement non collectif et celle de l'urbanisme, au sens des compétences "délivrance des autorisations d'urbanisme" et "planification territoriale" des collectivités et des intercommunalités. Elle se base sur l'analyse du fonctionnement de deux communautés d'agglomération de l'arrière-pays provençal, dans lesquels l'articulation de ces compétences est nécessaire pour un aménagement durable des territoires. Nous expliquons ici les difficultés liées aux démarches transversales qui apparaissent dans les territoires, en mettant notamment en lumière la recherche de leadership des différents services techniques concernés, ainsi que l'absence d'une véritable culture commune liée aux enjeux du développement durable et de l'étalement urbain

Les urbanistes face à l’inflation des normes juridiques : vers une nécessaire adaptation des pratiques professionnelles

International audienc

Grouping levels of exposure with same observable effects before class prediction in toxicogenomics.

International audienceGene expression profiling in toxicogenomics is often used to find molecular signature of toxicants. The range of doses chosen in toxicogenomics studies does not always represent all the possible effects on gene expression: several doses of toxicant can lead to the same observable effect on the transcriptome. This makes the problem of dose exposure prediction difficult to address. We propose a strategy allowing to gather the doses with similar effects prior to the computing of a molecular signature. The different gathering of doses are compared with criteria based on likelihood or Monte Carlo Cross Validation. The molecular signature is then determined via a voting algorithm. Experimental results point out that the obtained classifier has better prediction performances than the classifier computed according to the original labeling

Tissue Factor Expression in Non-small Cell Lung Cancer: Relationship with Vascular Endothelial Growth Factor Expression, Microvascular Density, and K-ras Mutation

IntroductionTissue factor (TF) is the physiological trigger of blood coagulation, but it could also have an important role in cancer by regulating VEGF expression and angiogenesis.MethodsTF expression was studied by real-time PCR in lung tumors of 64 patients with non-small-cell lung cancer (NSCLC) and by immunohistochemical analysis. The gene expression of two VEGF isoforms, VEGF165 and VEGF189, was also evaluated. Microvascular density (MVD) was studied by measuring Von Willebrand Factor (VWF) mRNA levels and by immunohistochemistry using an anti-CD34 antibody.ResultsTF mRNA levels were significantly lower than in corresponding non-affected lung tissues. However, TF expression was higher in T3-T4 tumors and this result was confirmed by immunohistochemistry. VEGF189 mRNA levels were ten times higher than those of VEGF165 and well correlated with TF mRNA levels. MVD was lower in the inner part of tumors than in the adjacent non-affected lung without being related to TF expression. Finally, codon 12 K-ras mutation was found in 8 lung carcinomas, and higher TF and VEGF189 mRNA levels were measured in mutated tissues (p < 0.001).ConclusionThese results suggest that high TF expression in lung tumors may result from K-ras mutation and contribute to NSCLC progression, probably via mechanisms other than angiogenesis

Diversity of farming systems integrating fish pond aquaculture in the province of Kinshasa in the Democratic Republic of the Congo

Agriculture and aquaculture systems are used by many farmers in various tropical countries of Asia, America and Africa. They have proven their relevancy to increase the productivity of farms by optimising nutrient fluxes and reducing requirements for external fertilisers. This article analysed the current state of fish farming and the way it is integrated with other farm subsystems in the urban/peri-urban and rural areas of Kinshasa, Democratic Republic of Congo. More precisely, it examined the allocation of resources at the farm level, the recovery of helophytes plants, and the fate of fish production choices and it explored the possibility of intensifying these existing integrated farming systems. After a census of ponds in the urban and rural areas of Kinshasa, an on-site survey was conducted on 150 fish pond farms to assess the different activities practiced on farms, the impact of integrating crops and livestock to fish pond aquaculture and the constraints of the system. A total of three thousand and twenty (3020) fish ponds were recorded in the urban and rural areas of Kinshasa. Among these farms integrated aquaculture-agriculture systems exist with a wide diversity of practices (about 79% of farms combined fish with livestock and/or vegetable production). No striking differences between fish farms according to the allocation of resources, fish production method such as monoculture or polyculture, the recovery of helophytes plants and the fate of fish production choice were found depending on the location. However, fish farms were differently managed when combined with agriculture and/or livestock. Regarding the integration of the different subsystems through nutrient fluxes, 11 different movements of material between subsystems were found in integrated farms. However, not all fluxes are equally used in all farms and therefore improvements cannot be generalised. Improvements to be explored are such as making better use of manure pond mud and helophyte plants. For this purpose, proper training of farmers might be critical. Finally, bringing farmers together in cooperatives could also contribute to reduce the cost of purchase and transportation of fish fry and feed

Voltage-gated sodium channels potentiate the invasive capacities of human non-small-cell lung cancer cell lines.

Ionic channel activity is involved in fundamental cellular behaviour and participates in cancerous features such as proliferation, migration and invasion which in turn contribute to the metastatic process. In this study, we investigated the expression and role of voltage-gated sodium channels in non-small-cell lung cancer cell lines. Functional voltage-gated sodium channels expression was investigated in normal and non-small-cell lung cancer cell lines. The measurement, in patch-clamp conditions, of tetrodotoxin-inhibitable sodium currents indicated that the strongly metastatic cancerous cell lines H23, H460 and Calu-1 possess functional sodium channels while normal and weakly metastatic cell lines do not. While all the cell lines expressed mRNA for numerous sodium channel isoforms, only H23, H460 and Calu-1 cells had a 250 kDa protein corresponding to the functional channel. The other cell lines also had another protein of 230 kDa which is not addressed to the membrane and might act as a dominant negative isoform to prevent channel activation. At the membrane potential of these cells, channels are partially open. This leads to a continuous entry of sodium, disrupting sodium homeostasis and down-stream signaling pathways. Inhibition of the channels by tetrodotoxin was responsible for a 40-50% reduction of in vitro invasion. These experiments suggest that the functional expression of voltage-gated sodium channels might be an integral component of the metastatic process in non-small-cell lung cancer cells probably through its involvement in the regulation of intracellular sodium homeostasis. These channels could serve both as novel markers of the metastatic phenotype and as potential new therapeutic targets

Nitrogen prediction model in smallholder farming system integrating pig and fish farming in the urban and rural areas of Kinshasa

peer reviewedThe modelling of nitrogen flow within integrated farms in aquaculture allows monitoring of the nitrogen evolution, which is one of the limiting elements in the farm production. This is one of the important ways to improve production in small integrated agricultural farms in rural and peri-urban areas of Kinshasa with limited financial resources. The model is built in order to use the nitrogen produced by the pig for fertilizing fish farming ponds. The pig module was calibrated, validated and ready to be used, contrary to the fish module which is not validated due to the lack of appropriate experience data. Result of pig module prediction, gives the cumulative N amount of the fattening period to 861.85 gN/pig for fecal nitrogen and 765.39 for urinary production very close to the measured value of 988.68 gN/pig and 887.55 gN/pig for N fecal and N urinary. The model shows that the variation in feed content leads to the variation in the N fecal and urinary production to the farm. Combined to the N from pig, N water in the fish pond is sensitive to N from pig addition and fish biomass. Change in factors that affect pig consumption and pig growing performance lead a variation in both N production by a pig and N water evolution in the pond water column