O processo de produção de uma injustiça ambiental e seus impactos: o caso do CTR Rio em Seropédica

O artigo tem como objetivo contar um pouco da história da implementação do aterro sanitário de Seropédica (CTR Rio) para receber todo o lixo do município do Rio de Janeiro, dentre outros municípios, ressaltando a frágil relação intermetrópole, em que a cidade central reforça o papel de zona de sacrifício da cidade periférica e, ainda, os reais impactos socioambientais, positivos e negativos, do funcionamento da unidade. Para tal, traz alguns referenciais teóricos, destacando o processo de metropolização em curso que, à luz da teoria da Justiça Ambiental, demonstra a nova função que Seropédica passa a desenvolver na dinâmica metropolitana.The article aims to tell a short history about the Seropédica landfill (CTR Rio) installation to receive all the waste from the municipality of Rio de Janeiro, among other municipalities, underscoring the fragile inter-metropolis relationship, on what the central city reinforces the role of the peripheral city as a sacrifice zone, and also the real, positive and negative, socioenvironmental impacts of the unit’s operation. It brings some theoretical references, highlighting the ongoing metropolization process that, in the light of the Environmental Justice theory, demonstrates the new function that Seropédica develops in the metropolitan dynamics.L’article vise à raconter un peu l’histoire de la mise en place de la décharge de Seropédica (CTR Rio) pour recevoir toutes les ordures de la municipalité de Rio de Janeiro, entre autres municipalité, en mettant en évidence la fragile relation intermétropole, dans laquelle la ville centrale renforce le rôle de la zone de sacrifice de la ville périphérique et, aussi, les impacts socio-environnementaux réels, positifs et négatifs, du fonctionnement de l’unité. À cette fin, il apporte quelques références théoriques, mettant en évidence le processus de métropolisation en cours qui, à la lumière de la théorie de la Justice Environnementale, démontre la nouvelle fonction que Seropédica commence à développer dans la dynamique métropolitaine.El articulo tiene el objetivo narrar la historia da implantación del relleno sanitario de Seropédica (CTR Rio) para recibir la toda la basura del municipio de Rio de Janeiro y de otros municipios, destacando la frágil relación intra metropolitana, en que la ciudad central refuerza el papel de la ciudad periférica como zona de sacrificio y, también, los reales impactos socioambientales, positivos y negativos, de la operación de la unidad fabril. Para esto, traemos algunas referencias teóricas, destacando el proceso de metropolización en curso que, a la luz de la teoría de la justicia ambiental, apunta la nueva función que Seropédica pasa a desarrollar en la dinámica metropolitana

Electron dense staining affinities of mouse oxytalan and elastic fibers

. The staining affinity of electron dense stains to mouse palatal elastic fibers and periodontal oxytalan fibers was assessed and compared. Tissues were stained routinely with uranyl acetate and lead citrate or with elastic tissue stains including: (1) silver tetraphenylporphine sulfonate, (2) tannic acid technique, and (3) a high iron diamine sequence. Staining results were assessed with an electron microscope. Palatal elastic fibers demonstrated staining affinity to all elastic stain techniques. Oxytalan fibers did not demonstrate affinity to elastic fiber stains used. Based on electron dense stains, elastic and oxytalan fibers were dissimilar, in contrast to results reported utilizing light microscopic stains.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72883/1/j.1600-0714.1980.tb00376.x.pd

Identification of candidate genes for drought tolerance in coffee by high-throughput sequencing in the shoot apex of different Coffea arabica cultivars.

BACKGROUND: Drought is a widespread limiting factor in coffee plants. It affects plant development, fruit production, bean development and consequently beverage quality. Genetic diversity for drought tolerance exists within the coffee genus. However, the molecular mechanisms underlying the adaptation of coffee plants to drought are largely unknown. In this study, we compared the molecular responses to drought in two commercial cultivars (IAPAR59, drought-tolerant and Rubi, drought-susceptible) of Coffea arabica grown in the field under control (irrigation) and drought conditions using the pyrosequencing of RNA extracted from shoot apices and analysing the expression of 38 candidate genes. RESULTS: Pyrosequencing from shoot apices generated a total of 34.7 Mbp and 535,544 reads enabling the identification of 43,087 clusters (41,512 contigs and 1,575 singletons). These data included 17,719 clusters (16,238 contigs and 1,575 singletons) exclusively from 454 sequencing reads, along with 25,368 hybrid clusters assembled with 454 sequences. The comparison of DNA libraries identified new candidate genes (n = 20) presenting differential expression between IAPAR59 and Rubi and/or drought conditions. Their expression was monitored in plagiotropic buds, together with those of other (n = 18) candidates genes. Under drought conditions, up-regulated expression was observed in IAPAR59 but not in Rubi for CaSTK1 (protein kinase), CaSAMT1 (SAM-dependent methyltransferase), CaSLP1 (plant development) and CaMAS1 (ABA biosynthesis). Interestingly, the expression of lipid-transfer protein (nsLTP) genes was also highly up-regulated under drought conditions in IAPAR59. This may have been related to the thicker cuticle observed on the abaxial leaf surface in IAPAR59 compared to Rubi. CONCLUSIONS: The full transcriptome assembly of C. arabica, followed by functional annotation, enabled us to identify differentially expressed genes related to drought conditions. Using these data, candidate genes were selected and their differential expression profiles were confirmed by qPCR experiments in plagiotropic buds of IAPAR59 and Rubi under drought conditions. As regards the genes up-regulated under drought conditions, specifically in the drought-tolerant IAPAR59, several corresponded to orphan genes but also to genes coding proteins involved in signal transduction pathways, as well as ABA and lipid metabolism, for example. The identification of these genes should help advance our understanding of the genetic determinism of drought tolerance in coffee

Can arbuscular mycorrhizal fungi and rhizobacteria facilitate P33 uptake in maize plants under water stress?

Arbuscular mycorrhizal fungi (AMF) and plant growth-promoting rhizobacteria (PGPR) are able to provide key ecosystem services, protecting plants against biotic and abiotic stresses. Here, we hypothesized that a combination of AMF (Rhizophagus clarus) and PGPR (Bacillus sp.) could enhance 33P uptake in maize plants under soil water stress. A microcosm experiment using mesh exclusion and a radiolabeled phosphorus tracer (33P) was installed using three types of inoculation: i) only AMF, ii) only PGPR, and iii) a consortium of AMF and PGPR, alongside a control treatment without inoculation. For all treatments, a gradient of three water-holding capacities (WHC) was considered i) 30% (severe drought), ii) 50% (moderate drought), and iii) 80% (optimal condition, no water stress). In severe drought conditions, AMF root colonization of dual-inoculated plants was significantly lower compared to individual inoculation of the AMF, whilst 33P uptake by dual-inoculated plants or plants inoculated with bacteria was 2.4-fold greater than the uninoculated treatment. Under moderate drought conditions the use of AMF promoted the highest 33P uptake by plants, increasing it by 2.1-fold, when compared to the uninoculated treatment. Without drought stress, AMF showed the lowest 33P uptake and, overall, plant P acquisition was lower for all inoculation types when compared to the severe and moderate drought treatments. The total shoot P content was modulated by the water-holding capacity and inoculation type, with the lowest values observed under severe drought and the highest values under moderate drought. The highest soil electrical conductivity (EC) values were found under severe drought in AMF-inoculated plants and the lowest EC for no drought in single or dual-inoculated plants. Furthermore, water-holding capacity influenced the total soil bacterial and mycorrhizal abundance over time, with the highest abundances being found under severe and moderate drought. This study demonstrates that the positive influence of microbial inoculation on 33P uptake by plants varied with soil water gradient. Furthermore, under severe stress conditions, AMF invested more in the production of hyphae, vesicles and spore production, indicating a significant carbon drain from the host plant as evidenced by the lack of translation of increased 33P uptake into biomass. Therefore, under severe drought the use of bacteria or dual-inoculation seems to be more effective than individual AMF inoculation in terms of 33P uptake by plants, while under moderate drought, the use of AMF stood out