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There continues to be cross-disciplinary interest in the patterns, extent, and changing contexts of segregation and spatial inequality more generally. The changes are clearly context dependent but at the same time there are broad generalizations that arise from the processes of residential sorting and selection. A major question in U.S. segregation research is how the growth of Asian and Hispanic populations is influencing patterns of segregation and diversity at the neighborhood level. In this article we use a variant of a nearest neighbor approach to map, graph, and evaluate patterns of race and ethnicity at varying scales. We show that using a multiscalar approach to segregation can provide a detailed and more complete picture of segregation. The research confirms work from other studies that segregation is decreasing between some groups and increasing between others, and the patterns, and processes can be described as dynamic diversity. In a series of maps of ethnic clusters and population homogeneity we show how metropolitan areas, represented in this case by Los Angeles, now display patterns of complex living arrangements with multiple groups inhabiting both local neighborhoods and wider community spheres.

Carnivores face important anthropogenic threats in agricultural areas from habitat loss and fragmentation, disturbance by domestic free-roaming dogs and cats, and direct hunting by humans. Anthropogenic disturbances are shifting the activity patterns of wild animals, likely modifying species interactions. We estimated changes in the activity patterns of the mesocarnivore guild of agricultural landscapes of the La Araucanía region in southern Chile in response to land-use intensification, comparing intra- and interspecific activity patterns at low and high levels of forest cover, fragmentation, and land ownership subdivision. Our focal species comprise the güiña or kod-kod (Leopardus guigna), two fox species (Lycalopex culpaeus and L. griseus), a skunk (Conepatus chinga), and one native mustelid (Galictis cuja), in addition to free-roaming dogs (Canis lupus familiaris) and cats (Felis catus) and their main mammalian prey species (i.e., Rodentia and Lagomorpha). In 23,373 trap nights, we totaled 21,729 independent records of our focal species. Our results show tendencies toward nocturnality at high land-use intensification, with potential impacts on species fitness. Nocturnal mesocarnivores decreased their diurnal/ crepuscular activity, while cathemeral activity shifted to nocturnal activity at high land-use intensification, but only when in sympatry with a competitor. High land-use intensification decreased the activity overlap between native and domestic mesocarnivores but increased the overlap between native mesocarnivores. High intensification also reduced overlap with prey species. Notably, foxes displayed peaks of activity opposing those of dogs, and plasticity in activity pattern when in sympatry with dogs, such as strategies to avoid encounters. We stress the need to suppress the free-roaming and unsupervised activity of dogs to mitigate impacts of high land-use intensification on mesocarnivores.

The Mi locus of tomato confers resistance to root knot nematodes. Tomato DNA spanning the locus was isolated as bacterial artificial chromosome clones, and 52 kb of contiguous DNA was sequenced. Three open reading frames were identified with similarity to cloned plant disease resistance genes. Two of them, Mi-1.1 and Mi-1.2, appear to be intact genes; the third is a pseudogene. A 4-kb mRNA hybridizing with these genes is present in tomato roots. Complementation studies using cloned copies of Mi-1.1 and Mi-1.2 indicated that Mi-1.2, but not Mi-1.1, is sufficient to confer resistance to a susceptible tomato line with the progeny of transformants segregating for resistance. The cloned gene most similar to Mi-1.2 is Prf, a tomato gene required for resistance to Pseudomonas syringae. Prf and Mi-1.2 share several structural motifs, including a nucleotide binding site and a leucine-rich repeat region, that are characteristic of a family of plant proteins, including several that are required for resistance against viruses, bacteria, fungi, and now, nematodes

Glucose is an essential signaling molecule that controls plant development and gene expression through largely unknown mechanisms. To initiate the dissection of the glucose signal transduction pathway in plants by using a genetic approach, we have identified an Arabidopsis mutant, gin1, (glucose-insensitive), in which glucose repression of cotyledon greening and expansion, shoot development, floral transition, and gene expression is impaired. Genetic analysis indicates that GIN1 acts downstream of the sensor hexokinase in the glucose signaling pathway. Surprisingly, gin1 insensitivity to glucose repression of cotyledon and shoot development is phenocopied by ethylene precursor treatment of wild-type plants or by constitutive ethylene biosynthesis and constitutive ethylene signaling mutants. In contrast, the ethylene insensitive mutant etr1-1 exhibits glucose hypersensitivity. Epistasis analysis places GIN1 downstream of the ethylene receptor, ETR1, and defines a new branch of ethylene signaling pathway that is uncoupled from the triple response induced by ethylene. The isolation and characterization of gin1 reveal an unexpected convergence between the glucose and the ethylene signal transduction pathways. GIN1 may function to balance the control of plant development in response to metabolic and hormonal stimuli that act antagonistically

Explaining the Chilean educational system and education in contexts of exclusion and inequality requires an analysis that goes beyond educational conditions and goes deeper into segregation. This article explores the relationship between housing and educational policies implemented by the neoliberal system from the 1980s to the present in Chile, particularly in the town of Bajos de Mena, Santiago. Considering these policies and their relationship in the definition of inequality, the complexity of educating in these contexts is analyzed, based on the analysis of content from the story of a school teacher in this sector, where the labor and educational relationship is conditioned for the violence and the symbolic distance between students and teachers.

The need to examine the entire scope of everyday activities of individuals in segregation studies has recently been recognized by social scientists and policy makers. To bring forth new insights into ethnic segregation through investigating the activities and movement undertaken by different population groups, we used mobile phone positioning data to compare the activity spaces of out-of-home nonemployment activities over a one-year period in Estonia and abroad. The results show that ethnicity has a significant influence on the activity spaces of individuals. The biggest differences between the two population groups occur in Estonia outside the respondents' home city of Tallinn, where the Russian-speaking minority was found to visit 45 percent fewer districts than Estonians. Moreover, they exhibit a preference for districts that are more heavily populated by a Russian-speaking population. With respect to international travel, the Russian-speaking minority visits fewer countries and are 3.6 times more likely to visit former Soviet Union countries than Estonians. The activity spaces of out-of-home nonemployment activities have fewer differences between the two groups in the respondents' home city of Tallinn. Overall, our results show that ethnic differences have less effect on the everyday activity space and a greater influence on the choices made regarding long-distance travel.

Legacies of social and environmental injustices can leave an imprint on the present and constrain transitions for more sustainable futures. In this article, we ask this question: What is the relationship of environmental inequality and histories of segregation? The answer for Baltimore is complex, where past practices of de jure and de facto segregation have created social and environmental legacies that persist on the landscape today. To answer this question, we examine the interactions among past and current environmental injustices in Baltimore from the late 1880s to the present using nearly twenty years of social and environmental justice research from the Baltimore Ecosystem Study (BES), a long-term social-ecological research project. Our research demonstrates that patterns and procedures in the city's early history of formal and informal segregation, followed by \"redlining\" in the 1930s, have left indelible patterns of social and environmental inequalities. These patterns are manifest in the distribution of environmental disamenities such as polluting industries, urban heat islands, and vulnerability to flooding, and they are also evident in the distribution of environmental amenities such as parks and trees. Further, our work shows how these legacies are complicated by changing perceptions of what counts as an environmental disamenity and amenity. Ultimately, we argue that the interactions among historical patterns, processes, and procedures over the long term are crucial for understanding environmental injustices of the past and present and for constructing sustainable cities for the future.

Many fundamental notions in geographic and social science research still tend to be conceptualized largely in static spatial terms, ignoring how our understanding of the issues we study can be greatly enriched through the lenses of time and human mobility. This article revisits three such notions: racial segregation, environmental exposure, and accessibility. It argues for the need to expand our analytical focus from static residential spaces to other relevant places and times in people's everyday lives. Mobility is an essential element of people's spatiotemporal experiences, and these complex experiences cannot be fully understood by just looking at where people live. As many social scientists are interested in studying segregation, environmental exposure, and accessibility, geographers can contribute to advancing temporally integrated analysis of these issues through careful examination of people's everyday experiences as their lives unfold in space and time. Interdisciplinary research along this line could have a broad impact on many disciplines beyond geography.

The interaction between Arabidopsis and the biotrophic oomycete Peronospora parasitica (downy mildew) provides an attractive model pathosystem to identify molecular components of the host that are required for genotype-specific recognition of the parasite. These components are the so-called RPP genes (for resistance to P. parasitica). Mutational analysis of the ecotype Wassilewskija (Ws-0) revealed an RPP-nonspecific locus called EDS1 (for enhanced disease susceptibility) that is required for the function of RPP genes on chromosomes 3 (RPP1/RPP14 and RPP10) and 4 (RPP12). Genetic analyses demonstrated that the eds1 mutation is recessive and is not a defective allele of any known RPP gene, mapping to the bottom arm of chromosome 3 (approximately 13 centimorgans below RPP1/RPP14). Phenotypically, the Ws-eds1 mutant seedlings supported heavy sporulation by P. parasitica isolates that are each diagnostic for one of the RPP genes in wild-type Ws-0; none of the isolates is capable of sporulating on wild-type Ws-0. Ws-eds1 seedlings exhibited enhanced susceptibility to some P. parasitica isolates when compared with a compatible wild-type ecotype, Columbia, and the eds1 parental ecotype, Ws-0. This was observed as earlier initiation of sporulation and elevated production of conidiosporangia. Surprisingly, cotyledons of Ws-eds1 also supported low sporulation by five isolates of P. parasitica from Brassica oleracea. These isolates were unable to sporulate on 100 ecotypes of Arabidopsis, including wild-type Ws-0. An isolate of Albugo candida (white blister) from B. oleracea also sporulated on Ws-eds1, but the mutant exhibited no alteration in phenotype when inoculated with several oomycete isolates from other host species The bacterial resistance gene RPM1, conferring specific recognition of the avirulence gene avrB from Pseudomonas syringae pv glycinea, was not compromised in Ws-eds1 plants. The mutant also retained full responsiveness to the chemical inducer of systemic acq

The photosynthetic apparatus in plants is protected against oxidative damage by processes that dissipate excess absorbed light energy as heat within the light-harvesting complexes. This dissipation of excitation energy is measured as nonphotochemical quenching of chlorophyll fluorescence. Nonphotochemical quenching depends primarily on the delta pH that is generated by photosynthetic electron transport, and it is also correlated with the amounts of zeaxanthin and antheraxanthin that are formed from violaxanthin by the operation of the xanthophyll cycle. To perform a genetic dissection of nonphotochemical quenching, we have isolated npq mutants of Chlamydomonas by using a digital video-imaging system. In excessive light, the npq1 mutant is unable to convert violaxanthin to antheraxanthin and zeaxanthin; this reaction is catalyzed by violaxanthin de-epoxidase. The npq2 mutant appears to be defective in zeaxanthin epoxidase activity, because it accumulates zeaxanthin and completely lacks antheraxanthin and violaxanthin under all light conditions. Characterization of these mutants demonstrates that a component of nonphotochemical quenching that develops in vivo in Chlamydomonas depends on the accumulation of zeaxanthin and antheraxanthin via the xanthophyll cycle. However, observation of substantial, rapid, delta pH-dependent nonphotochemical quenching in the npq1 mutant demonstrates that the formation of zeaxanthin and antheraxanthin via violaxanthin de-epoxidase activity is not required for all delta pH-dependent nonphotochemical quenching in this alga. Furthermore, the xanthophyll cycle is not required for survival of Chlamydomonas in excessive light