The Effect of Multiaxial Forging on the Grain Refinement of Low Alloyed Steel

Ultra fine grained low carbon low alloyed steel was formed by multiaxial forging. Altogether five passes of forging were made with decreasing temperature. The first two passes happened in the austenitic state of the steel, the third was made at the austenite-ferrite transition temperature. The fourth occurred in the austenitic-ferritic region, while the last pass was made in pure ferritic state. The intensive plastic deformation caused the austenite-ferrite transition temperature to be lowered, thus the undercooling was larger, and very small ferritic cores were produced. The following deformation made the grain structure even more fine

First data on the host ant usage of Large Blue from the Carpathian Basin

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Mindfulness in a digital math learning game:Insights from two randomized controlled trials

BackgroundMindfulness practices enhance executive function skills and academic achievement, spurring interest in integrating mindfulness interventions into education. Embedding mindfulness practice into a digital math game may provide a low-cost, scalable way to induce mindfulness and boost game-based learning, yet this approach remains unexplored.ObjectivesWe investigated the learning benefits of integrating mindfulness exercises in a digital math learning game and examined how students' trait mindfulness might moderate the outcomes.MethodsTwo classroom studies were conducted with 404 5th and 6th grade students from six public schools in the U.S. (nStudy 1 = 227, nStudy 2 = 177). The two randomized controlled experiments assigned students to one of the three conditions: passive control (playing the digital learning game Decimal Point), story-enriched active control, or mindfulness-enriched condition. Trait mindfulness, learning gains, and in-game problem-solving (including problem-solving duration, error count and correctness after reminder) were assessed. Study 2 included a manipulation check to better understand the effects of the mindfulness intervention.ResultsFindings showed no significant differences in learning gains, problem-solving duration or error count among the conditions. Students' trait mindfulness did not moderate these outcomes. Mindfulness reminders in the mindfulness-enriched game led to more correct answers after errors than jokes in the story-enriched game. Study 2 revealed that we failed to induce higher state mindfulness through the mindfulness inductions.ConclusionsMindfulness prompts could be especially beneficial for students experiencing frustration during gameplay, warranting more exploration for digital game-based instruction. We highlight barriers and future directions for fostering mindfulness through computer-based instruction in classrooms

Extracellular calcium reduction strongly increases the lytic capacity of pneumolysin from streptococcus pneumoniae in brain tissue

Background. Streptococcus pneumoniae causes serious diseases such as pneumonia and meningitis. Its major pathogenic factor is the cholesterol-dependent cytolysin pneumolysin, which produces lytic pores at high concentrations. At low concentrations, it has other effects, including induction of apoptosis. Many cellular effects of pneumolysin appear to be calcium dependent. Methods. Live imaging of primary mouse astroglia exposed to sublytic amounts of pneumolysin at various concentrations of extracellular calcium was used to measure changes in cellular permeability (as judged by lactate dehydrogenase release and propidium iodide chromatin staining). Individual pore properties were analyzed by conductance across artificial lipid bilayer. Tissue toxicity was studied in continuously oxygenated acute brain slices. Results. The reduction of extracellular calcium increased the lytic capacity of the toxin due to increased membrane binding. Reduction of calcium did not influence the conductance properties of individual toxin pores. In acute cortical brain slices, the reduction of extracellular calcium from 2 to 1 mM conferred lytic activity to pathophysiologically relevant nonlytic concentrations of pneumolysin. Conclusions. Reduction of extracellular calcium strongly enhanced the lytic capacity of pneumolysin due to increased membrane binding. Thus, extracellular calcium concentration should be considered as a factor of primary importance for the course of pneumococcal meningitis

Increased duodenal expression of miR-146a and-155 in pediatric Crohn's disease

AIM: To evaluate the role of microRNA (miR)-146a, -155 and -122 in the duodenal mucosa of pediatric patients with Crohn's disease (CD) and the effect of transforming growth factor-β (TGF-β) on these miRs in duodenal epithelial and fibroblast cells. METHODS: Formalin-fixed, paraffin-embedded biopsies derived from the macroscopically inflamed (CD inflamed: n = 10) and intact (CD intact: n = 10) duodenal mucosa of pediatric CD patients and control children (C: n = 10) were examined. Expression of miR-146a, -155 and -122 was determined by real-time polymerase-chain reaction (PCR). The expression of the above miRs was investigated in recombinant human TGF-β (1 nmol/L, 24 h) or vehicle treated small intestinal epithelial cells (CCL-241) and primary duodenal fibroblast cells derived from healthy children as well. RESULTS: Expression of miR-146a was significantly higher in the inflamed duodenal mucosa compared to the intact duodenal mucosa of children with CD (CD inflamed: 3.21 ± 0.50 vs CD intact: 0.62 ± 0.26, P ≤ 0.01) and to the control group (CD inflamed: 3.21 ± 0.50 vs C: 1.00 ± 0.33, P ≤ 0.05). The expression of miR-155 was significantly increased in the inflamed region of the duodenum compared to the control group (CD inflamed: 4.87 ± 1.02 vs CONTROL: 1.00 ± 0.40, P ≤ 0.001). The expression of miR-122 was unchanged in the inflamed or intact mucosa of CD patients compared to controls. TGF-β treatment significantly decreased the expression of miR-155 in small intestinal epithelial cells (TGF-β: 0.7 ± 0.083 vs CONTROL: 1 ± 0.09, P ≤ 0.05) and also the expression of miR-146a (TGF-β: 0.67 ± 0.04 vs CONTROL: 1 ± 0.15, P ≤ 0.01) and miR-155 (TGF-β: 0.72 ± 0.09 vs CONTROL: 1 ± 0.06, P ≤ 0.05) in primary duodenal fibroblasts compared to corresponding vehicle treated controls. TGF-β treatment did not influence the expression of miR-122. CONCLUSION: The elevated expression of miR-146a and -155 in the inflamed duodenal mucosa of CD patients suggests the role of these miRs in the pathomechanism of inflammatory bowel disease. Anti-inflammatory TGF-β plays an important role in the regulation of the expression of these miRs