1,094 research outputs found

    An ancient anterior patterning system promotes Caudal repression and head formation in Ecdysozoa.

    Get PDF
    SummaryPosterior expression of Caudal is required for early embryonic development in nematodes, arthropods, and vertebrates [1–9]. In Drosophila, ectopic Caudal in anterior cells can induce head defects, and in Caenorhabditis the absence of Caudal in anterior embryonic cells is required for proper development [6, 10]. Anterior Caudal repression in these species is achieved through unrelated translational repressors, the homeodomain protein Bicoid [11] and the KH domain factor Mex-3 [6, 12], respectively. Here we report that the Mex-3 ortholog in the flour beetle Tribolium plays a crucial role in head formation and that Caudal in this species is repressed by the combined activities of Mex-3 and Zen-2, a protein sharing common ancestry with the dipteran morphogen Bicoid. We propose that Mex-3 represents an ancient “anterior” promoting factor common to all Ecdysozoa (and maybe all Bilateria), whose role has been usurped in higher dipterans by Bicoid

    Large-Scale CO Maps of the Lupus Molecular Cloud Complex

    Full text link
    Fully sampled degree-scale maps of the 13CO 2-1 and CO 4-3 transitions toward three members of the Lupus Molecular Cloud Complex - Lupus I, III, and IV - trace the column density and temperature of the molecular gas. Comparison with IR extinction maps from the c2d project requires most of the gas to have a temperature of 8-10 K. Estimates of the cloud mass from 13CO emission are roughly consistent with most previous estimates, while the line widths are higher, around 2 km/s. CO 4-3 emission is found throughout Lupus I, indicating widespread dense gas, and toward Lupus III and IV. Enhanced line widths at the NW end and along the edge of the B228 ridge in Lupus I, and a coherent velocity gradient across the ridge, are consistent with interaction between the molecular cloud and an expanding HI shell from the Upper-Scorpius subgroup of the Sco-Cen OB Association. Lupus III is dominated by the effects of two HAe/Be stars, and shows no sign of external influence. Slightly warmer gas around the core of Lupus IV and a low line width suggest heating by the Upper-Centaurus-Lupus subgroup of Sco-Cen, without the effects of an HI shell.Comment: 54 pages, 27 figures, 5 tables. To appear in ApJS. Preprint also available (with full-size figures) from http://www.astro.ex.ac.uk/people/nfht/publications.html Datacubes available from http://www.astro.ex.ac.uk/people/nfht/resources.htm

    Why Have Economic Incentives Failed to Convince Farmers to Adopt Drip Irrigation in Southwestern Iran?

    Get PDF
    Sustainable water usage is an important global concern and an urgent priority, especially in dryland regions such as Iran. The Iranian government is actively addressing the challenge of water scarcity by encouraging farmers to adopt new water application technology. Its main element to decrease water consumption is to encourage new irrigation systems, in particular drip irrigation. However, despite the benefits of drip irrigation technologies and the availability of generous government subsidies, adoption rates of the improved irrigation technology remain critically low among Iranian farmers. Therefore, this study seeks to determine what is limiting the uptake of improved irrigation technology in Iran. While it is well known that acceptance of new technology ultimately depends on multiple and interrelated factors, we examine those factors affecting farmers’ adoption from three theoretical perspectives in the adoption literature: farmers’ socio-economic characteristics, social capital, and technology characteristics. A cross-sectional survey was undertaken in Behbahan district in Khuzestan province in southwest Iran. The sample comprises 174 farmers who adopted drip irrigation in that region and 100 non-adopters who were located in the same region. Discriminant analysis reveals that a socio-economic approach is the strongest model to predict adoption of drip irrigation technology in the study area, followed by models of technical characteristics, and social capital. These results can help agricultural extension agents and policy-makers design appropriate and effective strategies that facilitate the adoption of drip irrigation at an increasing rate

    Promotion of social skills promotion in preschool children

    Get PDF
    Social skills promotion in the child's relationships, in a preventive level, provides the development of and improvement in social competence, resulting in greater adaptability to the social environment. This research aimed to verify the effectiveness of a preventive program of social skills development in children between 4 and 6 years old and their parents. The results reflect the performance of 9 children of both sexes, with age between 5 and 6 years. CBCL (Achenbach, 1991) was used as the analysis instrument, answered by parents about the children's behaviors, before and after the participation in the program. Based on this analysis, it was possible to observe that there is a statistical difference between CBCL results before and after intervention, indicating changes in parents' perception about their children's behaviors and the probable increase in behaviors that facilitate social interaction.A promoção de habilidades sociais nas relaçÔes da criança, a um nĂ­vel preventivo, proporciona o desenvolvimento e melhoria da competĂȘncia social, resultando em maior adaptabilidade ao meio social. Esta pesquisa teve por objetivo verificar a eficĂĄcia de um programa preventivo de desenvolvimento de habilidades sociais em crianças de 4 a 6 anos e seus pais. Os resultados refletem o desempenho de 9 crianças, de ambos os sexos, com idade entre 5 e 6 anos. Como instrumento de anĂĄlise utilizou-se o Child Behavior Check-List (CBCL), respondido pelos pais em relação aos comportamentos dos filhos, antes e apĂłs a participação do programa. A partir desta anĂĄlise, foi possĂ­vel observar que existe uma diferença estatĂ­stica entre os resultados do CBCL prĂ© e pĂłs-intervenção, indicando mudanças na percepção dos comportamentos das crianças pelos pais e provĂĄvel aumento dos comportamentos facilitadores de interação social

    The ZEUS Forward Plug Calorimeter with Lead-Scintillator Plates and WLS Fiber Readout

    Get PDF
    A Forward Plug Calorimeter (FPC) for the ZEUS detector at HERA has been built as a shashlik lead-scintillator calorimeter with wave length shifter fiber readout. Before installation it was tested and calibrated using the X5 test beam facility of the SPS accelerator at CERN. Electron, muon and pion beams in the momentum range of 10 to 100 GeV/c were used. Results of these measurements are presented as well as a calibration monitoring system based on a 60^{60}Co source.Comment: 38 pages (Latex); 26 figures (ps

    Shaping farmers’ beliefs, risk perception and adaptation response through Construct Level Theory in the southwest Iran

    Get PDF
    Due to the severe effects of climate change on the agricultural sector, urgent action is required on the part of farmers and is, indeed, critical to reducing climate change impacts. However, reports globally revealed farmers' engagement in climate change adaptation is still insufficient, ambivalent, and inconsistent and farmers do not consider adaptation to be urgent. Researchers have argued that this issue is rooted in psychological biases beside other factors. Therefore, the aim of this study is to evaluate how psychological distance determines climate change beliefs, risk perception and adaptation strategies among Iranian farmers. A cross-sectional paper-based survey was conducted in the Dasht-e Azadegan county of Khuzestan province in southwest Iran. The study sample consisted of 250 farmers selected through a multi-stage random sampling process. An expert panel review and a pilot study were conducted to confirm convergent validity and reliability of the scales. The results confirm that all four dimensions of psychological distance influence water management adaptation strategies and non-farm activities. Moreover, all psychological dimensions, except the temporal dimension, affect adaptation in farming management. Thus, making climate change more proximal to decision makers could be a strategic way of encouraging individuals to take adaptive actions. This study emphasizes that concepts of psychological distance can be applied to help organizations (e.g., agriculture extension services) to understand farmers' risk perceptions and responses to climate change impacts and improve risk communication to better engage farmers in climate action
    • 

    corecore