1,178 research outputs found
Maternal inheritance of twist and analysis of MAPK activation in embryos of the polychaete Annelid Platynereis dumerilii
In this study, we aimed to identify molecular mechanisms involved in the specification of the 4d (mesentoblast) lineage in Platynereis dumerilii. We employ RT-PCR and in situ hybridization against the Platynereis dumerilii twist homolog (Pdu-twist) to reveal mesodermal specification within this lineage. We show that Pdu-twist mRNA is already maternally distributed. After fertilization, ooplasmatic segregation leads to relocation of Pdu-twist transcripts into the somatoblast (2d) lineage and 4d, indicating that the maternal component of Pdu-twist might be an important prerequisite for further mesoderm specification but does not represent a defining characteristic of the mesentoblast. However, after the primordial germ cells have separated from the 4d lineage, zygotic transcription of Pdu-twist is exclusively observed in the myogenic progenitors, suggesting that mesodermal specification occurs after the 4d stage. Previous studies on spiral cleaving embryos revealed a spatio-temporal correlation between the 4d lineage and the activity of an embryonic organizer that is capable to induce the developmental fates of certain micromeres. This has raised the question if specification of the 4d lineage could be connected to the organizer activity. Therefore, we aimed to reveal the existence of such a proposed conserved organizer in Platynereis employing antibody staining against dpERK. In contrast to former observations in other spiralian embryos, activation of MAPK signaling during 2d and 4d formation cannot be detected which questions the existence of a conserved connection between organizer function and specification of the 4d lineage. However, our experiments unveil robust MAPK activation in the prospective nephroblasts as well as in the macromeres and some micromeres at the blastopore in gastrulating embryos. Inhibition of MAPK activation leads to larvae with a shortened body axis, defects in trunk muscle spreading and improper nervous system condensation, indicating a critical function for MAPK signaling for the reorganization of embryonic tissues during the gastrulation process
Infinitival Clauses in Children With Typical and Late Language Emergence: Supporting a Dimensional Account of Language Delay
Children who do not speak single words by 2 years of age have been labeled as having late language emergence (LLE). While the majority of children with LLE recover by school-age, it has been argued that they often still perform below the level of their typical peers for specific linguistic skills. In this case, speech-language pathologists (SLPs) should consider language skills as varying along a dimension, rather than as simply impaired vs. unimpaired. To examine the dimensionality of language skill, this study compared infinitival clause production in 22 school-age children with and without LLE. The infinitive clauses were: catenatives, such as gonna; let us + verb, typically produced as letâs; unmarked infinitives such as make it go; and simple infinitives such as We want to run. The 22 participants included 11 with typical development and 11 with a history of LLE, sampled in a conversational context at 8-years of age. Analysis indicated that the groups did not statistically differ for use of the four types of infinitival clauses. However, the LLE group did use fewer simple infinitives, offering support for a dimensional model of language development
Functional Magnetic Resonance Imaging at High Spatiotemporal Resolution using EPI Combined with Different k-Space Undersampling Techniques at 3 Tesla
In functional magnetic resonance imaging (fMRI), major drawbacks of the commonly used echo-planar imaging (EPI) sequence are limited spatial specificity due to blurring and distortions as well as signal cancellation in areas affected by susceptibility gradients, such as the orbitofrontal cortex (OFC). In contrast, segmented EPI techniques facilitate ultra-high spatial but low temporal resolution. In this work, an EPI sequence with optimized slice-dependent echo time was developed avoiding signal drop outs in the OFC in 50 % of all subjects during fMRI (N = 12) compared to a standard EPI sequence. The average number of activated voxels detected in the OFC was thereby increased by a factor of 6.3. It was further shown for the first time that the spatial specificity in EPI fMRI at 3 T can be improved by increasing the matrix size in combination with the parallel imaging factor beyond conventional EPI parameter settings. By using the proposed high-resolution compared to a standard EPI protocol, the multi-subject analysis of a simple fingertapping task (N = 6) and a sophisticated motivation task (N = 15) showed robust and clearly less blurred activation in the sensorimotor cortex (SMC) and in the nucleus accumbens (NAcc), respectively. The number of separable clusters detected in the SMC and in the NAcc was thereby increased by a factor of 2.7 and 1.4, respectively. In order to perform fMRI at ultra-high spatial and high temporal resolution, a segmented EPI sequence was highly accelerated (R = 8) with the so-called UNFOLD technique. Both, the MR sequence and data post-processing were optimized facilitating the robust detection of neuronal activation at 0.7 x 0.7 mm2 resolution and half-brain coverage. Last but not least, a novel filtering strategy is proposed minimizing temporal coherences in UNFOLD datasets and thus improving the detectability of neuronal activation. By using the proposed filter compared to a standard filter, the number of activated voxels detected in the SMC (N = 5) was increased up to a factor of 1.4
Sustainability and Narrative: Is Equilibrium Tellable?
This essay wants to look at the strategies through which sustainability has been and can be narrativized. When thinking about the future today, sustainability is certainly one of the most prominent new concepts and one that is becoming more ubiquitous every day. But from a narratological perspective, there seems to be an interesting paradox: While narrative is essentially and fundamentally about change (events as building blocks of narrative are, after all, usually defined as state changes), about a disturbance of balance and âthings falling apart,â sustainability is equally fundamentally about persistent equilibrium, the absence of linear change (such as growth at the cost of depletion or degeneration). Where the ideal of narrative is progression, the ideal of sustainability is a higher form of stasis. An abstract look at the concept of sustainability on the one side, and the properties and affordances of narrative and narrativity on the other, will investigate whether the two agree or create some kind of friction, and if so, in how far emerging narrative genres adhere to such theoretical limitations
Endemic and cosmopolitan fungal taxa exhibit differential abundances in total and active communities of Antarctic soils
Our understanding of the diversity and community dynamics of soil fungi has increased greatly through the use of DNAâbased identification. Community characterisation of metabolically active communities via RNA sequencing has previously revealed differences between âactiveâ and âtotalâ fungal communities, which may be influenced by the persistence of DNA from nonâactive components. However, it is not known how fungal traits influence their prevalence in these contrasting community profiles. In this study, we coâextracted DNA and RNA from soil collected from three Antarctic islands to test for differences between total and active soil fungal communities. By matching these geographically isolated fungi against a global dataset of soil fungi, we show that widely dispersed taxa are often more abundant in the total community, whilst taxa restricted to Antarctica are more likely to have higher abundance in the active community. In addition, we find that active communities have lower richness, and show a reduction in the abundance of the most dominant fungi, whilst there are consistent differences in the abundances of certain taxonomic groups between the total and active communities. These results suggest that the views of soil fungal communities offered by DNAâ and RNAâbased characterisation differ in predictable ways
Eli Lilly: A Managerial Strategic Audit
This strategic audit assesses both internal and external landscapes affecting Eli Lilly; financial, qualitative, and competitive performance; strategy and governance; and recent strategic decisions. All information has been gathered from news reports, industry analyst reports, and Lillyâs investor reports, financial statements, and notes to investors. The purpose of this strategic audit is to showcase Lillyâs success in the brand name pharmaceutical industry based on the strategic decisions made in its 147 year history
EP151
An adaptation of the national OMK âReady, Set, Go!â training manual originally produced by the Washington State OMK team, 2007Elaine Johannes, L. Ann Domsch & Diane Mack, Ready, Set Go! Short Course Leaderâs Guide, Kansas State University, September 2008
Spirocyclic Drimanes from the Marine Fungus Stachybotrys sp. Strain MF347
A novel spirocyclic drimane coupled by two drimane fragment building blocks 2 and a new drimane 1 were identified in mycelia and culture broth of Stachybotrys sp. MF347. Their structures were established by spectroscopic means. This is the first example of spirocyclic drimane coupled by a spirodihydrobenzofuranlactam unit and a spirodihydroisobenzofuran unit; and the connecting position being N-C instead of an N and N connecting unit. Strain MF347 produced also the known spirocyclic drimanes stachybocin A (12) and stachybocin B (11) featured by two sesquiterpene-spirobenzofuran structural units connected by a lysine residue; the known spirocyclic drimanes chartarlactam O (5); chartarlactam K (6); F1839A (7); stachybotrylactam (8); stachybotramide (9); and 2α-acetoxystachybotrylactam acetate (10); as well as ilicicolin B (13), a known sesquiterpene. The relative configuration of two known spirobenzofuranlactams (3 and 4) was determined. All compounds were subjected to biological activity tests. The spirocyclic drimane 2, 11, and 12, as well as the sesquiterpene 13, exhibited antibacterial activity against the clinically relevant methicillin-resistant Staphylococcus aureus (MRSA)
Bodenkundliche Interpretation der scheinbaren elektrischen BodenleitfÀhigkeit [ECa] mit Hilfe von Grablochbeschrieben der BodenschÀtzung
Im Boden besteht ein Zusammenhang zwischen Tongehalt und elektrischer LeitfÀhigkeit. Die bodenkundliche Interpretation der LeitfÀhigkeitsmesswerte erfordert Informationen zur Bodenart. Als Grundlagen kommen u. a. beprobte und analysierte Schurfe und Grablochbeschriebe
der BodenschÀtzung in Frage.
Die Interpretation der ECa-Messwerte fĂŒr den Oberboden mit verschiedenartigen Profilinformationen fĂŒhrt in AbhĂ€ngigkeit
der HeterogenitÀt der SchlÀge in den Löss- und Sandlösslandschaften zu differenzierten Ergebnissen.
Durch den Einsatz von Grablochbeschrieben lÀsst sich der Aufwand an Analysen und GelÀndeerkundungen zur Interpretation der ECa-Werte reduzieren. Auf eine Verifizierung mit aktuellen Analysen sollte noch nicht verzichtet werden. Der Einsatz eines Tools, das auf Grundlage der Messwerte reprÀsentative Probenstandorte
bestimmt, hilft den quantitativen Aufwand zu optimiere
Growth and Mycotoxin Production by Chaetomium globosum Is Favored in a Neutral pH
Chaetomium globosum is frequently isolated in water-damaged buildings and produces two mycotoxins called chaetoglobosins A and C when cultured on building material. In this study, the influence of ambient pH on the growth of C. globosum was examined on an artificial medium. This fungus was capable of growth on potato dextrose agar ranging in pH from 4.3 to 9.4 with optimal growth and chaetoglobosin C production occurring at a neutral pH. In addition, our results show that sporulation is favored in an acidic environment
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