277 research outputs found
Asleep at the Switch: MEK Kinases Control Transit to Gliogenesis in Developing Cortex
In this issue of Neuron, Li et al. (2012) show that the neuron/glia cell fate switch of cortical progenitors is regulated by MEK1 and MEK2. The observations resonate with recent studies on the genesis of low-grade astrocytomas and highlight neuronal support functions of astrocytes in the postnatal brain
Police and Older Persons: Criteria Developed to Assess Training Materials, Methods
This article as revised was published as Johnson, Knowlton W.; Beirnard, Charles A.; & Stiles, Stephen R. (1981). "Police and Older Persons: Criteria Developed to Assess Training Materials, Methods." Training Aids Digest 6(11), November 1981.In what ways do law enforcement personnel and agencies use knowledge about the elderly? This article presents the findings of a recent study conducted by the International Training Research and Evaluation Council on how law enforcement trainees make use of the knowledge they gained through training materials developed by the National Retired Teachers Association/American Association of Retired Persons.[Introduction] /
Different Types of Knowledge Use /
The Study /
Knowledge Into Practice: Some Implication
Application of Dynamic pressure-balanced Seals in a Multi-stage Centrifugal Compressor
LecturesTest results for an ASME Power Test Code 10 (PTC) Type 1 test of a 4,500 psia (310 Bara) discharge pressure gas lift centrifugal
compressor outfitted with dynamic pressure-balanced seals at the impeller eyes; shaft interstage and division wall locations are
presented and compared to the same testing with conventional labyrinth seals. Both aerodynamic performance and rotor dynamic
stability, obtained via operational modal analysis (OMA), are presented. A clientâs motivation, along with the design and testing of
dynamic pressure-balanced (DPB) seals for turbomachinery are also presented in this paper.
With the DPB seals installed the test results indicate 2.8 percent lower power was required for the same head level across the entire
range of inlet flows and pressure ratios, when compared to the same testing with conventional labyrinth seals. Rotordynamic stability,
obtained via operational modal analysis (OMA), showed the dynamic pressure-balanced (DPB) seals exhibited log decs similar to
standard labyrinth seals across the entire range of flows and pressure ratios. The foregoing demonstrates both the aerodynamic and
mechanical/rotordynamic integrity of the dynamic pressure-balanced seals for oil and gas, turbomachinery applications
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A genome-wide in situ hybridization map of RNA-binding proteins reveals anatomically restricted expression in the developing mouse brain
BACKGROUND: In eukaryotic cells, RNA-binding proteins (RBPs) contribute to gene expression by regulating the form, abundance, and stability of both coding and non-coding RNA. In the vertebrate brain, RBPs account for many distinctive features of RNA processing such as activity-dependent transcript localization and localized protein synthesis. Several RBPs with activities that are important for the proper function of adult brain have been identified, but how many RBPs exist and where these genes are expressed in the developing brain is uncharacterized. RESULTS: Here we describe a comprehensive catalogue of the unique RBPs encoded in the mouse genome and provide an online database of RBP expression in developing brain. We identified 380 putative RBPs in the mouse genome. Using in situ hybridization, we visualized the expression of 323 of these RBP genes in the brains of developing mice at embryonic day 13.5, when critical fate choice decisions are made and at P0, when major structural components of the adult brain are apparent. We demonstrate i) that 16 of the 323 RBPs examined show neural-specific expression at the stages we examined, and ii) that a far larger subset (221) shows regionally restricted expression in the brain. Of the regionally restricted RBPs, we describe one group that is preferentially expressed in the E13.5 ventricular areas and a second group that shows spatially restricted expression in post-mitotic regions of the embryonic brain. Additionally, we find a subset of RBPs that share the same complex pattern of expression, in proliferating regions of the embryonic and postnatal NS and peripheral tissues. CONCLUSION: Our data show that, in contrast to their proposed ubiquitous involvement in gene regulation, most RBPs are not uniformly expressed. Here we demonstrate the region-specific expression of RBPs in proliferating vs. post-mitotic brain regions as well as cell-type-specific RBP expression. We identify uncharacterized RBPs that exhibit neural-specific expression as well as novel RBPs that show expression in non-neural tissues. The data presented here and in an online database provide a visual filter for the functional analysis of individual RBPs
Strategies for detecting biological molecules on Titan
Saturnâs moon Titan has all the ingredients needed to produce âlife as we know itâ. When exposed to liquid water, organic molecules analogous to those found on Titan produce a range of biomolecules such as amino acids. Titan thus provides a natural laboratory for studying the products of prebiotic chemistry. In this work, we examine the ideal locales to search for evidence of, or progression towards, life on Titan. We determine that the best sites to identify biological molecules are deposits of impact melt on the floors of large, fresh impact craters, specifically Sinlap, Selk, and Menrva craters. We find that it is not possible to identify biomolecules on Titan through remote sensing, but rather through in-situ measurements capable of identifying a wide range of biological molecules. Given the non-uniformity of impact melt exposures on the floor of a weathered impact crater, the ideal lander would be capable of precision targeting. This would allow it to identify the locations of fresh impact melt deposits, and/or sites where the melt deposits have been exposed through erosion or mass wasting. Determining the extent of prebiotic chemistry within these melt deposits would help us to understand how life could originate on a world very different from Earth
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Local Knowledge and Single IRBs for Multisite Studies: Challenges and Solutions
New federal policies require single IRB review for multisite studies, but many questions remain about how these IRBs will use local knowledge. The findings from our study, the first to examine how single IRBs perceive needs for local knowledge, reveal several challenges. Study respondents identified four potentially relevant types of local knowledge: about culture and linguistics, about geography and socioeconomics, about the researchers, and about the institutions. Such knowledge can potentially be obtained through local sites, but single IRBs may be unaware of potentially relevant local information, and lack of informal relationships may impede single IRBsâ reviews and interactions with researchers. While a recent, commonly used, standardized singleâIRB form asks three basic questions about local information, our findings suggest potential needs for additional information and, thus, have important implications for practice, policy, and research
Olig2-Regulated Lineage-Restricted Pathway Controls Replication Competence in Neural Stem Cells and Malignant Glioma
Recent studies have identified stem cells in brain cancer. However, their relationship to normal CNS progenitors, including dependence on common lineage-restricted pathways, is unclear. We observe expression of the CNS-restricted transcription factor, OLIG2, in human glioma stem and progenitor cells reminiscent of type C transit-amplifying cells in germinal zones of the adult brain. Olig2 function is required for proliferation of neural progenitors and for glioma formation in a genetically relevant murine model. Moreover, we show p21^(WAF1/CIP1), a tumor suppressor and inhibitor of stem cell proliferation, is directly repressed by OLIG2 in neural progenitors and gliomas. Our findings identify an Olig2-regulated lineage-restricted pathway critical for proliferation of normal and tumorigenic CNS stem cells
Digital cognitive behaviour therapy for insomnia in individuals with self-reported insomnia and chronic fatigue: A secondary analysis of a large scale randomized controlled trial
Insomnia is associated with fatigue, but it is unclear whether response to cognitive behaviour therapy for insomnia is altered in individuals with co-occurring symptoms of insomnia and chronic fatigue. This is a secondary analysis using data from 1717 participants with self-reported insomnia in a community-based randomized controlled trial of digital cognitive behaviour therapy for insomnia compared with patient education. We employed baseline ratings of the Chalder Fatigue Questionnaire to identify participants with more or fewer symptoms of self-reported chronic fatigue (chronic fatigue, n = 592; no chronic fatigue, n = 1125). We used linear mixed models with Insomnia Severity Index, Short Form-12 mental health, Short Form-12 physical health, and the Hospital Anxiety and Depression Scale separately as outcome variables. The main covariates were main effects and interactions for time (baseline versus 9-week follow-up), intervention, and chronic fatigue. Participants with chronic fatigue reported significantly greater improvements following digital cognitive behaviour therapy for insomnia compared with patient education on the Insomnia Severity Index (Cohen's d = 1.36, pâ<â0.001), Short Form-12 mental health (Cohen's d = 0.19, p = 0.029), and Hospital Anxiety and Depression Scale (Cohen's d = 0.18, p = 0.010). There were no significant differences in the effectiveness of digital cognitive behaviour therapy for insomnia between chronic fatigue and no chronic fatigue participants on any outcome. We conclude that in a large community-based sample of adults with insomnia, co-occurring chronic fatigue did not moderate the effectiveness of digital cognitive behaviour therapy for insomnia on any of the tested outcomes. This may further establish digital cognitive behaviour therapy for insomnia as an adjunctive intervention in individuals with physical and mental disorders.publishedVersio
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