2,562 research outputs found
Designing Building Blocks for Open-Ended Early Literacy Software
English has a convoluted relationship between its pronunciation and spelling,
which obscures its phonological structure for early literacy learners. This
convoluted relationship has implications for early literacy software,
particularly for open-ended, child-driven designs. A tempting way to bypass
this issue is to use manipulables (blocks) that are directly tied to phonemes.
However, creating phoneme-based blocks leads to two design challenges: (a) how
to represent phonemes visually in a child-accessible way and (b) how to account
for context-dependent spelling. In the present work, we approached these
challenges by developing a set of animated, onomatopoeia-based mnemonic
characters, one per phoneme, that can take the shape of different graphemes.We
applied the characters to a construction-based literacy app to simplify
independent word-building for literacy beginners. We tested the app during a
13-week-long period with 4- to 5-year-olds in kindergarten classrooms. Children
showed visible interest in the characters and properly grasped the principles
of their functioning. However, the blocks were not sufficient to scaffold
independent word building, leading children to rely on other scaffolding
mechanisms. To test the characters' efficiency as mnemonics, we evaluated their
effect on the speed and accuracy of finding phonemes on a keyboard. The results
suggest that there were both children who benefitted from the characters in
this task and those who performed better without them. The factors that
differentiated these two categories are currently unclear. To help further
research on phonetic mnemonics in literacy learning software, we are making the
characters available to the research community.Comment: This is a published manuscript for the paper published in the
International Journal of Child-Computer Interaction. Sharing on ArXiv is in
accordance with Elsevier sharing polic
Molecular biogeography and host relations of a parasitoid fly
© 2019 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. Successful geographic range expansion by parasites and parasitoids may also require host range expansion. Thus, the evolutionary advantages of host specialization may trade off against the ability to exploit new host species encountered in new geographic regions. Here, we use molecular techniques and confirmed host records to examine biogeography, population divergence, and host flexibility of the parasitoid fly, Ormia ochracea (Bigot). Gravid females of this fly find their cricket hosts acoustically by eavesdropping on male cricket calling songs; these songs vary greatly among the known host species of crickets. Using both nuclear and mitochondrial genetic markers, we (a) describe the geographical distribution and subdivision of genetic variation in O. ochracea from across the continental United States, the Mexican states of Sonora and Oaxaca, and populations introduced to Hawaii; (b) demonstrate that the distribution of genetic variation among fly populations is consistent with a single widespread species with regional host specialization, rather than locally differentiated cryptic species; (c) identify the more-probable source populations for the flies introduced to the Hawaiian islands; (d) examine genetic variation and substructure within Hawaii; (e) show that among-population geographic, genetic, and host song distances are all correlated; and (f) discuss specialization and lability in host-finding behavior in light of the diversity of cricket songs serving as host cues in different geographically separate populations
The Otterbein Miscellany - June 1982
https://digitalcommons.otterbein.edu/miscellany/1006/thumbnail.jp
Report of the 1988 2-D Intercomparison Workshop, chapter 3
Several factors contribute to the errors encountered. With the exception of the line-by-line model, all of the models employ simplifying assumptions that place fundamental limits on their accuracy and range of validity. For example, all 2-D modeling groups use the diffusivity factor approximation. This approximation produces little error in tropospheric H2O and CO2 cooling rates, but can produce significant errors in CO2 and O3 cooling rates at the stratopause. All models suffer from fundamental uncertainties in shapes and strengths of spectral lines. Thermal flux algorithms being used in 2-D tracer tranport models produce cooling rates that differ by as much as 40 percent for the same input model atmosphere. Disagreements of this magnitude are important since the thermal cooling rates must be subtracted from the almost-equal solar heating rates to derive the net radiative heating rates and the 2-D model diabatic circulation. For much of the annual cycle, the net radiative heating rates are comparable in magnitude to the cooling rate differences described. Many of the models underestimate the cooling rates in the middle and lower stratosphere. The consequences of these errors for the net heating rates and the diabatic circulation will depend on their meridional structure, which was not tested here. Other models underestimate the cooling near 1 mbar. Suchs errors pose potential problems for future interactive ozone assessment studies, since they could produce artificially-high temperatures and increased O3 destruction at these levels. These concerns suggest that a great deal of work is needed to improve the performance of thermal cooling rate algorithms used in the 2-D tracer transport models
Size- and charge-dependent non-specific uptake of PEGylated nanoparticles by macrophages
The assessment of macrophage response to nanoparticles is a central component in the evaluation of new nanoparticle designs for future in vivo application. This work investigates which feature, nanoparticle size or charge, is more predictive of non-specific uptake of nanoparticles by macrophages. This was investigated by synthesizing a library of polymer-coated iron oxide micelles, spanning a range of 30â100 nm in diameter and â23 mV to +9 mV, and measuring internalization into macrophages in vitro. Nanoparticle size and charge both contributed towards non-specific uptake, but within the ranges investigated, size appears to be a more dominant predictor of uptake. Based on these results, a protease-responsive nanoparticle was synthesized, displaying a matrix metalloproteinase-9 (MMP-9)-cleavable polymeric corona. These nanoparticles are able to respond to MMP-9 activity through the shedding of 10â20 nm of hydrodynamic diameter. This MMP-9-triggered decrease in nanoparticle size also led to up to a six-fold decrease in nanoparticle internalization by macrophages and is observable by T2-weighted magnetic resonance imaging. These findings guide the design of imaging or therapeutic nanoparticles for in vivo targeting of macrophage activity in pathologic states
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Board) directed staff to convene a team of independent scientific experts to provide input regarding sediment impairment in the Freshwater, Bear, Jordan, Stitz, and Elk River watersheds. The panel was convened in August of 2002, and, produced the above-noted document o
Proteomic and transcriptomic profiling reveals a link between the PI3K pathway and lower estrogen-receptor (ER) levels and activity in ER+ breast cancer
IntroductionAccumulating evidence suggests that both levels and activity of the estrogen receptor (ER) and the progesterone receptor (PR) are dramatically influenced by growth-factor receptor (GFR) signaling pathways, and that this crosstalk is a major determinant of both breast cancer progression and response to therapy. The phosphatidylinositol 3-kinase (PI3K) pathway, a key mediator of GFR signaling, is one of the most altered pathways in breast cancer. We thus examined whether deregulated PI3K signaling in luminal ER+ breast tumors is associated with ER level and activity and intrinsic molecular subtype.MethodsWe defined two independent molecular signatures of the PI3K pathway: a proteomic (reverse-phase proteomic array) PI3K signature, based on protein measurement for PI3K signaling intermediates, and a PI3K transcriptional (mRNA) signature based on the set of genes either induced or repressed by PI3K inhibitors. By using these signatures, we scored each ER+ breast tumor represented in multiple independent expression-profiling datasets (four mRNA, n = 915; one protein, n = 429) for activation of the PI3K pathway. Effects of PI3K inhibitor BEZ-235 on ER expression and activity levels and cell growth were tested by quantitative real-time PCR and cell proliferation assays.ResultsWithin ER+ tumors, ER levels were negatively correlated with the PI3K activation scores, both at the proteomic and transcriptional levels, in all datasets examined. PI3K signature scores were also higher in ER+ tumors and cell lines of the more aggressive luminal B molecular subtype versus those of the less aggressive luminal A subtype. Notably, BEZ-235 treatment in four different ER+ cell lines increased expression of ER and ER target genes including PR, and treatment with IGF-I (which signals via PI3K) decreased expression of ER and target genes, thus further establishing an inverse functional relation between ER and PI3K. BEZ-235 had an additional effect on tamoxifen in inhibiting the growth of a number of ER+ cell lines.ConclusionsOur data suggest that luminal B tumors have hyperactive GFR/PI3K signaling associated with lower ER levels, which has been correlated with resistance to endocrine therapy. Targeting PI3K in these tumors might reverse loss of ER expression and signaling and restore hormonal sensitivity
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KLF15 Is a Molecular Link between Endoplasmic Reticulum Stress and Insulin Resistance
Obesity places major demands on the protein folding capacity of the endoplasmic reticulum (ER), resulting in ER stress, a condition that promotes hepatic insulin resistance and steatosis. Here we identify the transcription factor, Kruppel-like factor 15 (KLF15), as an essential mediator of ER stress-induced insulin resistance in the liver. Mice with a targeted deletion of KLF15 exhibit increased hepatic ER stress, inflammation, and JNK activation compared to WT mice; however, KLF15-/- mice are protected against hepatic insulin resistance and fatty liver under high-fat feeding conditions and in response to pharmacological induction of ER stress. The mammalian target of rapamycin complex 1 (mTORC1), a key regulator of cellular energy homeostasis, has been shown to cooperate with ER stress signaling pathways to promote hepatic insulin resistance and lipid accumulation. We find that the uncoupling of ER stress and insulin resistance in KLF15-/- liver is associated with the maintenance of a low energy state characterized by decreased mTORC1 activity, increased AMPK phosphorylation and PGC-1α expression and activation of autophagy, an intracellular degradation process that enhances hepatic insulin sensitivity. Furthermore, in primary hepatocytes, KLF15 deficiency markedly inhibits activation of mTORC1 by amino acids and insulin, suggesting a mechanism by which KLF15 controls mTORC1-mediated insulin resistance. This study establishes KLF15 as an important molecular link between ER stress and insulin action
Identifying Child Anxiety Through Schools-identification to intervention (iCATS-i2i):protocol for a cluster randomised controlled trial to compare screening, feedback and intervention for child anxiety problems to usual school practice
Background: Systematically screening for child anxiety problems, and offering and delivering a brief, evidence-based intervention for children who are identified as likely to benefit would minimise common barriers that families experience in accessing treatment. We have developed a short parent-report child anxiety screening questionnaire, and procedures for administering screening questionnaires, sharing screening outcomes with families, and offering and delivering a brief parent-led online intervention (OSI: Online Support and Intervention for child anxiety) through schools. This trial aims to evaluate clinical and health economic outcomes for (1) children (aged 8â9) who screen positive for anxiety problems at baseline (target population) and (2) the wider population of all children in participating classes (total population) in schools randomly allocated to receive identification-to-intervention procedures and usual school practice (âscreening and interventionâ), compared to assessment and usual school practice only (âusual school practiceâ). Methods: The trial design is a parallel-group, superiority cluster randomised controlled trial, with schools (clusters) randomised to âscreening and interventionâ or âusual school practiceâ arms in a 1:1 ratio stratified according to the level of deprivation within the school. We will recruit schools and participants in two phases (a pilot phase (Phase 1) and Phase 2), with progression criteria assessed prior to progressing to Phase 2. In total, the trial will recruit 80 primary/junior schools in England, and 398 children (199 per arm) who screen positive for anxiety problems at baseline (target population). In schools allocated to âscreening and interventionâ: (1) parents/carers will complete a brief parent-report child anxiety screening questionnaire (at baseline) and receive feedback on their childâs screening outcomes (after randomisation), (2) classes will receive a lesson on managing fears and worries and staff will be provided with information about the intervention and (3) parents/carers of children who screen positive for anxiety problems (target population) will be offered OSI. OSI will also be available for any other parents/carers of children in participating classes (total population) who request it. We will collect child-, parent- and teacher-report measures for the target population and total population at baseline (before randomisation), 4Â months, 12Â months and 24Â months post-randomisation. The primary outcome will be the proportion of children who screen positive for anxiety problems at baseline (target population) who screen negative for anxiety problems 12Â months post-randomisation. Discussion: This trial will establish if systematic screening for child anxiety problems, sharing screening outcomes with families and delivering a brief parent-led online intervention through schools is effective and cost-effective. Trial registration: ISRCTN registry ISRCTN76119074. Prospectively registered on 4.1.2022.</p
The Third wave in globalization theory
This essay examines a proposition made in the literature that there are three waves in globalization theoryâthe globalist, skeptical, and postskeptical or transformational wavesâand argues that this division requires a new look. The essay is a critique of the third of these waves and its relationship with the second wave. Contributors to the third wave not only defend the idea of globalization from criticism by the skeptics but also try to construct a more complex and qualified theory of globalization than provided by first-wave accounts. The argument made here is that third-wave authors come to conclusions that try to defend globalization yet include qualifications that in practice reaffirm skeptical claims. This feature of the literature has been overlooked in debates and the aim of this essay is to revisit the literature and identify as well as discuss this problem. Such a presentation has political implications. Third wavers propose globalist cosmopolitan democracy when the substance of their arguments does more in practice to bolster the skeptical view of politics based on inequality and conflict, nation-states and regional blocs, and alliances of common interest or ideology rather than cosmopolitan global structures
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