Vegetation characterization for the Lake Ontario stopover project

Avian conservation is imperative because birds provide many beneficial ecosystem services. Bird mortality is highest during the migratory period due to habitat loss from anthropogenic land cover change. On the way to and from breeding grounds, migrants make many stopovers to refuel and rest for the next leg of their journey. The abundance, distribution, and quality of the stopover habitat are important for a successful migration. The southern shore of Lake Ontario in Western New York has received attention for conservation, because it provides critical stopover habitats for migrants. Performing vegetation and bird surveys, at specific stopover locations, provides useful information for finding correlations between bird abundance and richness with specific habitat characteristics and provides insight to the presence of invasive plant species in an area. The field data also help validate the accuracy of the 2001 National Land Cover Database (NLCD), which supplied land cover information for the geographic information system model used to initially locate the sampling sites. Sampling site locations were predicted by the model using distance from the shoreline of the lake and percent woody cover within 5 kilometers. The model accurately predicted the location of forested habitat with only minor discrepancies between specific forested land cover types when comparing to the actual land cover at the sampling plots. The field surveys suggested that birds prefer stopover habitats with a higher abundance of saplings and large shrubs. Birds were observed to be higher in abundance and richness in more isolated habitats with less than ten percent wooded cover in a 5 km radius around the patch. They also seemed to prefer habitat near the shore (0-2 kilometers) or further away from the shore (32-75 kilometers). The identified preferences that migrants have for specific stopover characteristics in this study can be incorporated in the conservation plans for quality stopover habitats in the Western New York region. The model can serve as a template for identifying more stopover habitats in the future

Epithelial to mesenchymal transition: New and old insights from the classical neural crest model

The epithelial-to-mesenchymal transition (EMT) is an important event converting compact and ordered epithelial cells into migratory mesenchymal cells. Given the molecular and cellular similarities between pathological and developmental EMTs, studying this event during neural crest development offers and excellent in vivo model for understanding the mechanisms underlying this process. Here, we review new and old insight into neural crest EMT in search of commonalities with cancer progression that might aid in the design of specific therapeutic prevention

A PHD12–Snail2 repressive complex epigenetically mediates neural crest epithelial-to-mesenchymal transition

Neural crest cells form within the neural tube and then undergo an epithelial to mesenchymal transition (EMT) to initiate migration to distant locations. The transcriptional repressor Snail2 has been implicated in neural crest EMT via an as of yet unknown mechanism. We report that the adaptor protein PHD12 is highly expressed before neural crest EMT. At cranial levels, loss of PHD12 phenocopies Snail2 knockdown, preventing transcriptional shutdown of the adhesion molecule Cad6b (Cadherin6b), thereby inhibiting neural crest emigration. Although not directly binding to each other, PHD12 and Snail2 both directly interact with Sin3A in vivo, which in turn complexes with histone deacetylase (HDAC). Chromatin immunoprecipitation revealed that PHD12 is recruited to the Cad6b promoter during neural crest EMT. Consistent with this, lysines on histone 3 at the Cad6b promoter are hyperacetylated before neural crest emigration, correlating with active transcription, but deacetylated during EMT, reflecting the repressive state. Knockdown of either PHD12 or Snail2 prevents Cad6b promoter deacetylation. Collectively, the results show that PHD12 interacts directly with Sin3A/HDAC, which in turn interacts with Snail2, forming a complex at the Cad6b promoter and thus revealing the nature of the in vivo Snail repressive complex that regulates neural crest EMT

Estimating the direct and indirect impact of typhoons on plant performance: Evidence from Chinese manufacturers

We quantify the impact of typhoons on manufacturing plants in China. To this end we construct a panel data set of precisely geo-located plants and a plant-level measure of typhoon damage derived from storm track data and a wind field model. Our econometric results reveal that the impact on plant sales can be considerable, although the effects are relatively short-lived. Annual total costs to Chinese plants from typhoons are estimated to be in the range of US$ 3.2 billion (2017 prices), or about 1 per cent of average turnover. When we examine the channels by which plants react to a storm event we find that there is some buffering through an increase in debt and a reduction in liquidity. In terms of propagating the shock through foreign or domestic channels, our estimates suggest that plants prefer to reduce sales to domestic buyers more than foreign buyers and purchases from foreign rather than domestic suppliers. We also find some evidence of a negative indirect effect on turnover through spillovers from customers and a positive effect through damage to very nearby competitors

Epigenetic regulation in neural crest development

The neural crest is a migratory and multipotent cell population that plays a crucial role in many aspects of embryonic development. In all vertebrate embryos, these cells emerge from the dorsal neural tube then migrate long distances to different regions of the body, where they contribute to formation of many cell types and structures. These include much of the peripheral nervous system, craniofacial skeleton, smooth muscle, and pigmentation of the skin. The best-studied regulatory events guiding neural crest development are mediated by transcription factors and signaling molecules. In recent years, however, growing evidence supports an important role for epigenetic regulation as an additional mechanism for controlling the timing and level of gene expression at different stages of neural crest development. Here, we summarize the process of neural crest formation, with focus on the role of epigenetic regulation in neural crest specification, migration, and differentiation as well as in neural crest related birth defects and diseases

Ispitivanja statičke kompresije i rezonantne vibracije celularnih materijala dobivenih gravitacijskim sinterovanjem šupljih brončanih kugli

The cylindrical and rod-shaped specimens were prepared by gravity sintering from Cu-Sn hollow spheres. On these samples, both static compression tests and measurements of resonance frequencies were performed. The compressive stress-strain curves revealed the features characteristic for a closed-cell ductile cellular solid. The removal of in general open porosity among loosely packed closed metallic hollow spheres was recognized as the principal mode of plastic deformation. The approximative effective moduli of elasticity were determined for cellular materials under consideration by means of the measurements of resonance frequencies on rod-shaped specimens.Cilindrični i šipkasti uzorci su pripremljeni gravitacionim sinterovanjem šupljih Cu-Sn kugli. Na tim uzorcima su provedena ispitivanja statičke kompresije i mjerenja rezonantnih frekvencija. Krivulja naprezanje-rastezanje nam pokazuje svojstva karakteristična za plastične celularne krute materijale sa zatvorenim ćelijama. Uklanjanje uglavnom otvorene povezanosti među labavo povezanim šupljim metalnim kuglama prepoznajemo kao glavni način plastične deformacije. Za celularne materijale koji se razmatraju određeni su približno učinkoviti moduli elastičnosti mjerenjem frekvencija rezonancije na šipkasto oblikovanim uzorcima

Epigenetic inactivation of mir-203 as a key step in neural crest epithelial-to-mesenchymal transition

miR-203 is a tumor-suppressor microRNA with known functions in cancer metastasis. Here, we explore its normal developmental role in the context of neural crest development. During the epithelial-to-mesenchymal transition of neural crest cells to emigrate from the neural tube, miR-203 displays a reciprocal expression pattern with key regulators of neural crest delamination, Phf12 and Snail2, and interacts with their 3′UTRs. We show that ectopic maintenance of miR-203 inhibits neural crest migration in chick, whereas its functional inhibition using a ‘sponge’ vector or morpholinos promotes premature neural crest delamination. Bisulfite sequencing further shows that epigenetic repression of miR-203 is mediated by the de novo DNA methyltransferase DNMT3B, the recruitment of which to regulatory regions on the miR-203 locus is directed by SNAIL2 in a negative-feedback loop. These findings reveal an important role for miR-203 in an epigenetic-microRNA regulatory network that influences the timing of neural crest delamination.Fil: Sanchez Vasquez, Estefania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas (subsede Chascomús) | Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas (subsede Chascomús); ArgentinaFil: Bronner, Marianne E.. California Institute of Technology; Estados UnidosFil: Strobl Mazulla, Pablo Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas (subsede Chascomús) | Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas (subsede Chascomús); Argentin

DNA methyltransferase3A as a molecular switch mediating the neural tube-to-neural crest fate transition

Here, we explore whether silencing via promoter DNA methylation plays a role in neural versus neural crest cell lineage decisions. We show that DNA methyltransferase3A (DNMT3A) promotes neural crest specification by directly mediating repression of neural genes like Sox2 and Sox3. DNMT3A is expressed in the neural plate border, and its knockdown causes ectopic Sox2 and Sox3 expression at the expense of neural crest markers. In vivo chromatin immunoprecipitation of neural folds demonstrates that DNMT3A specifically associates with CpG islands in the Sox2 and Sox3 promoter regions, resulting in their repression by methylation. Thus, DNMT3A functions as a molecular switch, repressing neural to favor neural crest cell fate

Nuclear magnetic resonance measurements reveal the origin of the Debye process in monohydroxy alcohols

Monohydroxy alcohols show a structural relaxation and at longer time scales a Debye-type dielectric peak. From spin-lattice relaxation experiments using different nuclear probes an intermediate, slower-than-structural dynamics is identified for n-butanol. Based on these findings and on diffusion measurements, a model of self-restructuring, transient chains is proposed. The model is demonstrated to explain consistently the so far puzzling observations made for this class of hydrogen-bonded glass forming liquids.Comment: 4 pages, 4 figure