B-Function Expression in the Flower Center Underlies the Homeotic Phenotype of Lacandonia schismatica (Triuridaceae)

Spontaneous homeotic transformations have been described in natural populations of both plants and animals, but little is known about the molecular-genetic mechanisms underlying these processes in plants. In the ABC model of floral organ identity in Arabidopsis thaliana, the B- and C-functions are necessary for stamen morphogenesis, and C alone is required for carpel identity. We provide ABC model-based molecular-genetic evidence that explains the unique inside-out homeotic floral organ arrangement of the monocotyledonous mycoheterotroph species Lacandonia schismatica (Triuridaceae) from Mexico. Whereas a quarter million flowering plant species bear central carpels surrounded by stamens, L. schismatica stamens occur in the center of the flower and are surrounded by carpels. The simplest explanation for this is that the B-function is displaced toward the flower center. Our analyses of the spatio-temporal pattern of B- and C-function gene expression are consistent with this hypothesis. The hypothesis is further supported by conservation between the B-function genes of L. schismatica and Arabidopsis, as the former are able to rescue stamens in Arabidopsis transgenic complementation lines, and Ls-AP3 and Ls-PI are able to interact with each other and with the corresponding Arabidopsis B-function proteins in yeast. Thus, relatively simple molecular modifications may underlie important morphological shifts in natural populations of extant plant taxa

On the reliability of negative heat capacity measurements

A global protocol for the thermostatistical analysis of hot nuclear sources is discussed. Within our method of minimization of variances we show that the abnormal kinetic energy fluctuation signal recently reported in different experimental data (M.D'Agostino et al.-Phys. Lett. B 473 (2000) 219, N. Le Neindre et al.- contr. to the XXXVIII Bormio Winter Meeting on Nucl. Phys. (2001) 404) is a genuine signal of a first order phase transition in a finite system.Comment: 15 Postscript figures, submitted to NUCL. Phys. A on 24-apr-200

Slit2N/Robo1 Inhibit HIV-gp120-Induced Migration and Podosome Formation in Immature Dendritic Cells by Sequestering LSP1 and WASp

Cell-mediated transmission and dissemination of sexually-acquired human immunodeficiency virus 1 (HIV-1) in the host involves the migration of immature dendritic cells (iDCs). iDCs migrate in response to the HIV-1 envelope protein, gp120, and inhibiting such migration may limit the mucosal transmission of HIV-1. In this study, we elucidated the mechanism of HIV-1-gp120-induced transendothelial migration of iDCs. We found that gp120 enhanced the binding of Wiskott-Aldrich Syndrome protein (WASp) and the Actin-Related Protein 2/3 (Arp2/3) complex with β-actin, an interaction essential for the proper formation of podosomes, specialized adhesion structures required for the migration of iDCs through different tissues. We further identified Leukocyte-Specific Protein 1 (LSP1) as a novel component of the WASp-Arp2/3-β-actin complex. Pretreating iDCs with an active fragment of the secretory glycoprotein Slit2 (Slit2N) inhibited HIV-1-gp120-mediated migration and podosome formation, by inducing the cognate receptor Roundabout 1 (Robo1) to bind to and sequester WASp and LSP1 from β-actin. Slit2N treatment also inhibited Src signaling and the activation of several downstream molecules, including Rac1, Pyk2, paxillin, and CDC42, a major regulator of podosome formation. Taken together, our results support a novel mechanism by which Slit2/Robo1 may inhibit the HIV-1-gp120-induced migration of iDCs, thereby restricting dissemination of HIV-1 from mucosal surfaces in the host

The role of parental achievement goals in predicting autonomy-supportive and controlling parenting

Although autonomy-supportive and controlling parenting are linked to numerous positive and negative child outcomes respectively, fewer studies have focused on their determinants. Drawing on achievement goal theory and self-determination theory, we propose that parental achievement goals (i.e., achievement goals that parents have for their children) can be mastery, performance-approach or performance-avoidance oriented and that types of goals predict mothers' tendency to adopt autonomy-supportive and controlling behaviors. A total of 67 mothers (aged 30-53 years) reported their goals for their adolescent (aged 13-16 years; 19.4 % girls), while their adolescent evaluated their mothers' behaviors. Hierarchical regression analyses showed that parental performance-approach goals predict more controlling parenting and prevent acknowledgement of feelings, one autonomy-supportive behavior. In addition, mothers who have mastery goals and who endorse performance-avoidance goals are less likely to use guilt-inducing criticisms. These findings were observed while controlling for the effect of maternal anxiety

Sociology or a Marxist Social Science: An Analysis of the Work of Karl Korsch

My thesis outlines the thought of Karl Korsch by examining the relation of Marxist theory to the historical movement which includes the development of the proletariat on a worldwide scale. This is a unified subjective and objective movement of the socialization of labor. The analysis demonstrates that the original Marxist theory is no longer applicable for todays' society, since it is an historical product itself. Marxism did not stand outside of the movement of history thus it underwent transformations and consequently became a bourgeois philosophy, a false consciousness, no longer the expression of the process of the socialization of labor. Theory was seen as having an independent existence apart from the social relations in the realm of pure thought. Korsch criticized the theorists who took this stance. He claimed that the theorists of the Second International, Lenin and Luxemburg, all drew a sharp line between consciousness and being. Consciousness was understood by them as an independent, static essence which was contrasted to being, as a reflection of an external object. Korsch maintained that together they form a moment in one unified social historical process. Korsch provided us with an original analysis of the counterrevolution. Yet he did not go far enough with it. He focused primarily on the political sphere instead of explaining this period as a time of the expansion of social labor within the relations of capital and wage labor. This gave rise to new political forms. Groups in control tried to change the distribution process but could not alter the process of production. Korsch demonstrated that Marxist theory still provided the framework which could be further developed into a social science. The framework includes; the primacy of the base, the analysis of value, a critical and non-dogmatic approach to Marxist theory, and the principle of historical specificity. This framework provides us with a way to understand the process of the socialization of labor. Korsch presented us with a new definition of revolution as the process of the socialization of labor and the means of production. The revolutionary potential lies with the forces of production, the real labor power of individuals who are bound within the relations of capital and wage-labor. Korsch criticized Marx for his emphasis on the bourgeois form of revolution which relied primarily on the political sphere of the superstructure.Master of Arts (MA

A Consensus Proposal for Nutritional Indicators to Assess the Sustainability of a Healthy Diet: The Mediterranean Diet as a Case Study

BACKGROUND: There is increasing evidence of the multiple effects of diets on public health nutrition, society, and environment. Sustainability and food security are closely interrelated. The traditional Mediterranean Diet (MD) is recognized as a healthier dietary pattern with a lower environmental impact. As a case study, the MD may guide innovative inter-sectorial efforts to counteract the degradation of ecosystems, loss of biodiversity, and homogeneity of diets due to globalization through the improvement of sustainable healthy dietary patterns. This consensus position paper defines a suite of the most appropriate nutrition and health indicators for assessing the sustainability of diets based on the MD. METHODS: In 2011, an informal International Working Group from different national and international institutions was convened. Through online and face-to-face brainstorming meetings over 4 years, a set of nutrition and health indicators for sustainability was identified and refined. RESULTS: Thirteen nutrition indicators of sustainability relating were identified in five areas. Biochemical characteristics of food (A1. Vegetable/animal protein consumption ratios; A2. Average dietary energy adequacy; A3. Dietary Energy Density Score; A4. Nutrient density of diet), Food Quality (A5. Fruit and vegetable consumption/intakes; A6. Dietary Diversity Score), Environment (A7. Food biodiversity composition and consumption; A8. Rate of Local/regional foods and seasonality; A9. Rate of eco-friendly food production and/or consumption), Lifestyle (A10. Physical activity/physical inactivity prevalence; A11. Adherence to the Mediterranean dietary pattern), Clinical Aspects (A12. Diet-related morbidity/mortality statistics; A13. Nutritional Anthropometry). A standardized set of information was provided for each indicator: definition, methodology, background, data sources, limitations of the indicator, and references. CONCLUSION: The selection and analysis of these indicators has been performed (where possible) with specific reference to the MD. Sustainability of food systems is an urgent priority for governments and international organizations to address the serious socioeconomic and environmental implications of short-sighted and short-term practices for agricultural land and rural communities. These proposed nutrition indicators will be a useful methodological framework for designing health, education, and agricultural policies in order, not only to conserve the traditional diets of the Mediterranean area as a common cultural heritage and lifestyle but also to enhance the sustainability of diets in general

Spatio-temporal metabolic rifts in urban construction material circularity

Global demand for resources currently exceeds Earth's carrying capacity. Representing a majority of global resource use, and associated environmental burdens, cities must address overconsumption by improving material circularity. This work explores the potential for the construction sector to reduce the indirect environmental impacts connected to increasing material circularity in the coming years. An urban metabolism simulation tool based on system dynamics and life cycle thinking is deployed to estimate the effects of circularization on environmental impacts. Illustrating with a case study of Montréal (Canada), impacts are disaggregated to supplier nations, provinces and territories. As material circularity increases over time, impacts decrease in the sub-national and international regions, but increase in the city due to the activities associated with second life valorisation. In supplier regions, especially Brazil, Mexico, and Norway, environmental impacts decrease between 80 and 100 % in all 18 impact categories by 2050. However, these decreases are found to be shared mostly among Canada's more developed trading partners, revealing an environmental justice risk for circular materiality to disproportionally favour the better-off. Five of the 18 categories did not undergo spatial burden-shifting, improving at all spatial levels in the assessment, while 13 showed decreased environmental impacts remotely at the expense of increased impacts within Montréal