362 research outputs found

    Black middle-class neighborhoods in Louisville through multiple lenses.

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    This dissertation is an articles-based, mixed methods study that analyzes Black middle-class neighborhood attainment in Louisville. Racialized social structure theory is the theoretical framework that is employed to make sense of the adverse positionality of Black middle-class neighborhoods. Racialized social structure theory posits that individuals are placed in racial categories that are hierarchically arranged, which, at the neighborhood level, translates to White and Black householders advancing their material interests in competing ways. These competing interests are asymmetrical in terms of power relations, which means that the neighborhood choices of the Black middle-class are constrained by the routinized ways that the racialized social structure diminishes their claims to middle-class status. The first and second articles primarily utilize the 2016 American Community Survey to compare Black middle-class neighborhood attainment across similarly sized urban areas and to analyze the spatial proximity of Black middle-class households and households considered poor, respectively. These articles find that the segregation levels faced by the Black middle class affect how many Black middle-class households live in prototypical middle-class neighborhoods and show that durable geographical patterns are interwoven with the racial characterizations of neighborhoods, both yielding disadvantages to neighborhoods with growing Black populations. In the third article, the perspectives of middle-class Blacks are brought to the forefront and uncover that a great deal of ownership is expressed by respondents in terms of the home buying process and their neighborhood lives and a relationship is found between familial class background and neighborhood preferences. Overall, Black middle-class neighborhoods in Louisville are socioeconomically heterogeneous. However, this heterogeneity reflects neighborhood choices that are constrained by trade-offs between living in neighborhoods conducive to wealth-building or living in neighborhoods that are less economically advantaged, but allow for more social comfort

    Primary scab control using a "during-infection" spray timing and the effect on fruit quality and yield in organic apple production

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    Organic apple production in Europe depends to a great extent on the use of copper fungicides for scab control (Venturia inaequalis). The objective of this 6-year study (2003-2008) conducted in Belgium was to determine measures for reducing the use of copper fungicides in organic apple production. The effectiveness of a 'during-infection' spray strategy using wettable sulphur (with or without copper), lime sulphur, potassium bicarbonate, silicon and five natural plant extracts (orange peel, soapbark, tea seed, quinoa seed and grapefruit seed) for controlling primary scab was investigated in a split-plot field experiment. Four apple cultivars that express a gradient of partial scab resistance were included: a high scab-susceptible cultivar (cv. 'Pinova'), a medium scab-susceptible cultivar (cv. 'Pirouette') and two old cultivars expressing low to very low scab susceptibility (cvs. 'Reinette Hernaut' and 'Reinette des Capucins'). Apart from these cultivars, four monogenic Vf scab-resistant cultivars (cvs. 'Initial', 'Topaz', 'Zvatava' and 'JN 20/33/58') were also included in the experimental orchard. In order to reduce the amount of fungicide required, two strategies were used: a specific spray timing involving spraying during the infection processes, before fungal penetration, determined by the RIMpro software warning system, and a tunnel sprayer machine for optimal treatment applications. Depending on the year, a total of 8-12 applications were made annually. Under field conditions that were highly conducive disease, low rates of elemental sulphur (≤ 40 kg.ha-1 per year) combined with low rates of copper (≤ 2.1 kg.ha-1 per year) provided the best scab control and reduced scab severity on the leaves and fruits by 85-100%, depending on the year and cultivar, compared with the untreated control. In most cases, the lime sulphur spray treatment, which used more elemental sulphur but did not use copper, provided a similar level of scab control to the combined wettable sulphur and copper spray treatment. Sulphur, potassium bicarbonate and all plant extracts significantly reduced scab severity on leaves and fruits. In general, the treatments increased the yield of the high and medium scab-susceptible cultivars as well as that of the low and very low scab-susceptible cultivars. Under these experimental conditions, none of the treatments caused phytotoxicity, increased fruit russet or led to undesirable soil and fruit residues at harvest. The potential and limitations of "during-infection" spraying as a protection strategy against apple scab in organic farming are discussed

    Farmers’ management of functional biodiversity goes beyond pest management in organic European apple orchards

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    Supporting functional biodiversity (FB), which provides natural pest regulation, is an environmentally sound and promising approach to reduce pesticide use in perennial cultures such as apple, especially in organic farming. However, little is known about farmers’ practices and motivations to implement techniques that favor FB, especially whether or not they really expect anything from FB in terms of pest regulation. In fact, FB-supporting techniques (FB-techniques) are massively questioned by practitioners due to inadequate information about their effectiveness. An interview survey was performed in eight European countries(i) to describe farmers’ practices and identify promising FB-techniques: (ii) to better understand their perceptions of and values associated with FB; and (iii) to identify potential drivers of (non-)adoption. Fifty-five advisors and 125 orchard managers with various degrees of experience and convictions about FB were interviewed and a total of 24 different FB-techniques which can be assigned to three different categories (ecological infrastructures, farming practices and redesign techniques) were described. Some were well-established measures (e.g., hedges and bird houses), while others were more marginal and more recent (e.g., animal introduction and compost). On average, farmers combined more than four techniques that had been implemented over a period of 13 years, especially during their establishment or conversion period. In general, it was difficult for farmers to evaluate the effectiveness of individual FB-techniques on pest regulation. They considered FB-techniques as a whole, targeting multiple species, and valued multiple ecosystem services in addition to pest regulation. The techniques implemented and their associated values differed among farmers who adopted various approaches towards FB. Three different approaches were defined: passive, active and integrated. Their appraisal of FB is even more complex because it may change with time and experience. These findings provide empirical evidence that the practical implementation of promising techniques remains a challenge, considering the diversity of situations and evaluation criteria. Increased cooperation between researchers, farmers and advisors should more effectively target research, advisory support and communication to meet farmers’ needs and perceptions

    La recherche-intervention pour une transition vers le développement durable

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    La transition vers le développement durable est ici abordée par la démarche de la recherche-intervention. L’implication des chercheurs dans une action collective les oblige à construire de nouveaux rapports entre recherche et acteurs de manière à rendre la première pertinente par rapport aux enjeux identifiés. La démarche étudiée dans cet article, le cas d’une filière bovine bio, comporte une étape d’identification des préoccupations et des points de vue. Leur analyse conduit, d’un côté à une proposition d’action qui reconfigure les relations et les stabilise via des objets intermédiaires, et de l’autre à une proposition de recherches qui peuvent répondre aux défis de l’action en cours. Ces recherches relèvent de différents modèles selon la manière dont les acteurs et les objets peuvent y être associés. Leurs résultats alimentent l’action en cours et débouchent sur un nouveau référentiel de filière.The transition towards sustainable development is tackled by the “deliberative research” approach. The involvement of researchers in the collective action, obliges them to build new relations between research and actors, making the research relevant regarding the identified stakes. The approach – in this case of an organic beef food chain – starts by an identification step of concerns and viewpoints. The analysis leads on one hand to a proposal of action, which reconfigures the relations and stabilizes intermediary objects and on the other hand to research proposals which are intended to give answers to issues related to the action. These researches are related to different models according the way they associate actors and objects. Their outcomes feed the running action and open to a new food chain «référentiel» (frame of reference)

    Loss of mRNA surveillance pathways results in widespread protein aggregation

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    From Springer Nature via Jisc Publications RouterHistory: received 2017-12-04, accepted 2018-02-15, registration 2018-02-19, pub-electronic 2018-03-01, online 2018-03-01, collection 2018-12Publication status: PublishedAbstract: Eukaryotic cells contain translation-associated mRNA surveillance pathways which prevent the production of potentially toxic proteins from aberrant mRNA translation events. We found that loss of mRNA surveillance pathways in mutants deficient in nonsense-mediated decay (NMD), no-go decay (NGD) and nonstop decay (NSD) results in increased protein aggregation. We have isolated and identified the proteins that aggregate and our bioinformatic analyses indicates that increased aggregation of aggregation-prone proteins is a general occurrence in mRNA surveillance mutants, rather than being attributable to specific pathways. The proteins that aggregate in mRNA surveillance mutants tend to be more highly expressed, more abundant and more stable proteins compared with the wider proteome. There is also a strong correlation with the proteins that aggregate in response to nascent protein misfolding and an enrichment for proteins that are substrates of ribosome-associated Hsp70 chaperones, consistent with susceptibility for aggregation primarily occurring during translation/folding. We also identified a significant overlap between the aggregated proteins in mRNA surveillance mutants and ageing yeast cells suggesting that translation-dependent protein aggregation may be a feature of the loss of proteostasis that occurs in aged cell populations

    Author Correction: Loss of mRNA surveillance pathways results in widespread protein aggregation

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    From Springer Nature via Jisc Publications RouterHistory: registration 2021-07-28, pub-electronic 2021-08-12, online 2021-08-12, collection 2021-12Publication status: Publishe

    Upwelling and outwelling effects on the benthic regime of the continental shelf off Galicia, NW Spain

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    The benthic regime off the Galician coast of NW Spain was surveyed to assess biogenic enrichment from coastal upwelling and detritus outwelling from the rĂ­as, large coastal embayments: the RĂ­as Altas along the northern and the RĂ­as Bajas along the western coast, which have intense mussel aquaculture. Sediment samples were collected from 1984 to 1986 and used for geological, microbiological, and macrofaunal studies. Sub-bottom acoustic profiler records and grab and core samples identified two main mud deposits on the western shelf that were aligned north to south and parallel with the coastline. The major axis of the mud deposit, which extended south to the Portuguese border, is associated with the three most southern rĂ­as (Arosa, Pontevedra and Vigo) along the western shelf. Sediment particle size analysis showed that sediments on the western shelf were heterogeneous, and grain size increased from the inner shelf to the shelf break. On the northern shelf, sediments exhibited a more homogeneous textural distribution. Sediment organic matter followed a similar pattern with that of particle size. The highest organic matter values, 10%, occurred on the western shelf nearest the RĂ­as Bajas, but these values decreased offshore to between 2 and 4%. On the northern shelf organic matter content was generally less than 4% but with patches of higher organic content. The composition and structure of macroinfauna on the northern shelf, where seasonal coastal upwelling results in benthic enrichment, showed mainly small, surface feeding, and fast growing polychaetes. In contrast, macroinfauna on the western shelf showed more subsurface, deposit-feeding polychaetes. A main difference between the two shelves is that off the rĂ­as Bajas, besides coastal upwelling, outwelling from the highly productive rĂ­as Bajas, with their intense mussel aquaculture, also enriches the coastal sediment regime with a steady source of organic matter. Although seasonal and interannual variations occurred in the benthic bacteria, their general density distribution followed the pattern of organic matter content and particle grain size seasonally and interannually. The highest numbers of bacteria occurred in the upwelling region off the northern shelf and nearest the RĂ­as Bajas on the western shelf. Both coastal upwelling and organic outwelling from the rĂ­as Bajas support benthic production alongthe western Galician shelf. The main commercialdemersal finfishalongthis coast is hake, Merluccius merluccius and blue-whiting, Micomesistius poutassou. The norwegian lobster, Nephrops norvegicus is also an important crop, and is more abundant off the rĂ­as Bajas in the finer and organic-richsediments where there are abundant prey resources of benthic infauna
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