830 research outputs found

    WNT8 and BMP2B co-regulate non-axial mesoderm patterning during zebrafish gastrulation

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    AbstractDuring vertebrate mesoderm formation, fates are established according to position in the dorsoventral (D/V) axis of the embryo. Initially, maternal signaling divides nascent mesoderm into axial (dorsal) and non-axial (ventral) domains. Although the subsequent subdivision of non-axial mesoderm into multiple D/V fate domains is known to involve zygotic Wnt8 and BMP signaling as well as the Vent/Vox/Ved family of transcriptional repressors, how levels of signaling activity are translated into differential regulation of fates is not well understood. To address this question, we have analyzed zebrafish embryos lacking Wnt8 and BMP2b. Zebrafish wnt8; swr (bmp2b) double mutants display a progressive loss of non-axial mesoderm and a concomitant expansion of axial mesoderm during gastrulation. Mesoderm induction and specification of the axial domain occur normally in wnt8; swr mutants, but dorsal mesoderm genes eventually come to be expressed throughout the mesoderm, suggesting that the establishment of non-axial mesoderm identity requires continual repression of dorsal mesoderm factors, including repressors of ventral genes. Loss-of-function for Vent, Vox, and Ved phenocopies the wnt8; swr mutant phenotype, consistent with Wnt8 and BMP2b maintaining non-axial mesoderm identity during gastrulation through the regulation of these three transcriptional repressors. We postulate that timely differentiation of the mesoderm requires the maintenance of non-axial mesoderm identity by Wnt8 and BMP2b at the onset of gastrulation followed by subdivision of the non-axial mesoderm into different functional domains during gastrulation

    A Guide to Integrating Behavioral/Process Addictions into Counselor Education Programs

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    Changes in CACREP standards and DSM-5diagnoses reflect the need to train counselors in the screening and treatment of behavioral/process additions (BPAs). This guide presents foundational issues counselor educators and supervisors may consider when developing an addictions course inclusive of BPAs. It also highlights components of a sample syllabus for a BPA course, including student learning outcomes (SLOs), course topics, materials, and activities/assignments. Developing curricula inclusive of BPAs is a way for counselor educators to begin to advocate for comprehensive addictions curricula within existing counselor education programs, in order to improve the competency of the counselors they train

    A Guide to Integrating Behavioral/Process Addictions into Counselor Education Programs

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    Changes in CACREP standards and DSM-5 diagnoses reflect the need to train counselors in the screening and treatment of behavioral/process additions (BPAs). This guide presents foundational issues counselor educators and supervisors may consider when developing an addictions course inclusive of BPAs. It also highlights components of a sample syllabus for a BPA course, including student learning outcomes (SLOs), course topics, materials, and activities/assignments. Developing curricula inclusive of BPAs is a way for counselor educators to begin to advocate for comprehensive addictions curricula within existing counselor education programs, in order to improve the competency of the counselors they train

    Luminous Infrared Galaxies with the Submillimeter Array: I. Survey Overview and the Central Gas to Dust Ratio

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    We present new data obtained with the Submillimeter Array for a sample of fourteen nearby luminous and ultraluminous infrared galaxies. The galaxies were selected to have luminosity distances D < 200 Mpc and far-infrared luminosities log(L_FIR) > 11.4. The galaxies were observed with spatial resolutions of order 1 kpc in the CO J=3-2, CO J=2-1, 13CO J=2-1, and HCO+ J=4-3 lines as well as the continuum at 880 microns and 1.3 mm. We have combined our CO and continuum data to measure an average gas-to-dust mass ratio of 120 +/- 28 (rms deviation 109) in the central regions of these galaxies, very similar to the value of 150 determined for the Milky Way. This similarity is interesting given the more intense heating from the starburst and possibly accretion activity in the luminous infrared galaxies compared to the Milky Way. We find that the peak H_2 surface density correlates with the far-infrared luminosity, which suggests that galaxies with higher gas surface densities inside the central kiloparsec have a higher star formation rate. The lack of a significant correlation between total H_2 mass and far-infrared luminosity in our sample suggests that the increased star formation rate is due to the increased availability of molecular gas as fuel for star formation in the central regions. In contrast to previous analyses by other authors, we do not find a significant correlation between central gas surface density and the star formation efficiency, as trace by the ratio of far-infrared luminosity to nuclear gas mass. Our data show that it is the star formation rate, not the star formation efficiency, that increases with increasing central gas surface density in these galaxies.Comment: 66 pages, 39 figures, aastex preprint format; to be published in ApJ Supplements. Version of paper with full resolution figures available at http://www.physics.mcmaster.ca/~wilson/www_xfer/ULIRGS_publi

    Two steps forward, one step back: Race/ethnicity and student achievement in education policy research

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    The goal of this study is to bring the discussion of ethnic heterogeneity and the racial/ethnic classification of students for research purposes into the education policy arena. The relationship between race and ethnicity and academic achievement is focused on in particular The heterogeneity of academic performance in reading and math is demonstrated between subgroups of Hispanic and Asian/Pacific Island students, using the National Educational Longitudinal Study of 1988 (NELS '88). In the care of both the Hispanic and Asian/Pacific Island aggregate groups there are substantial, though not always statistically significant, academic performance differences among ethnic subgroups, with a range of math performance among Hispanic subgroups of 10.7 points (mean score = 34.4) between Cuban and Puerto Rican students and a range of math performance among Asian/Pacific Island students of 15.3 points (mean score 41.0) between West Asian and Pacific Island students

    The Rise and Fall of Wiñaymarka: Rethinking Cultural and Environmental Interactions in the Southern Basin of Lake Titicaca

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    Investigations of how past human societies managed during times of major climate change can inform our understanding of potential human responses to ongoing environmental change. In this study, we evaluate the impact of environmental variation on human communities over the last four millennia in the southern Lake Titicaca basin of the Andes, known as Lake Wiñaymarka. Refined paleoenvironmental reconstructions from new diatom-based reconstructions of lake level together with archaeological evidence of animal and plant resource use from sites on the Taraco Peninsula, Bolivia, reveal frequent climate and lake-level changes within major cultural phases. We posit that climate fluctuations alone do not explain major past social and political transformations but instead that a highly dynamic environment contributed to the development of flexible and diverse subsistence practices by the communities in the Titicaca Basin

    Mapping the Constrained Coding Regions in the human genome to their corresponding proteins

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    Constrained Coding Regions (CCRs) in the human genome have been derived from DNA sequencing data of large cohorts of healthy control populations, available in the Genome Aggregation Database (gnomAD) [1]. They identify regions depleted of protein-changing variants and thus identify segments of the genome that have been constrained during human evolution. By mapping these DNA-defined regions from genomic coordinates onto the corresponding protein positions and combining this information with protein annotations, we have explored the distribution of CCRs and compared their co-occurrence with different protein functional features, previously annotated at the amino acid level in public databases. As expected, our results reveal that functional amino acids involved in interactions with DNA/RNA, protein-protein contacts and catalytic sites are the protein features most likely to be highly constrained for variation in the control population. More surprisingly, we also found that linear motifs, linear interacting peptides (LIPs), disorder-order transitions upon binding with other protein partners and liquid-liquid phase separating (LLPS) regions are also strongly associated with high constraint for variability. We also compared intra-species constraints in the human CCRs with inter-species conservation and functional residues to explore how such CCRs may contribute to the analysis of protein variants. As has been previously observed, CCRs are only weakly correlated with conservation, suggesting that intraspecies constraints complement interspecies conservation and can provide more information to interpret variant effects
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