18 research outputs found

    A Correlational Study of Student Self-Image, Academic Performance, School Involvement and Seeking Help in a Crisis

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    This research examined the relationship between students\u27 self-image, academic performance, involvement in school activities to their willingness to seek help for crisis counseling. Questionnaire data were collected from eighty-seven students in a Council Bluffs, Iowa school. The research null hypotheses suggest that; 1) There is no correlation between high school students\u27 self-image and seeking crisis counseling, 2) There is no correlation between academic performance and seeking crisis counseling. Although there was no support for the original hypotheses, a significant correlation between seeking help and gender prompted additional analyses moderated by gender. Additional analyses also examined inter-correlations between type of help seeking and age, also moderated by gender. Additional analyses also examined inter-correlations between types of help seeking and age, also moderated by gender. The results of these analyses suggest that younger girls are more willing than older girls to seek help from counselors and others. In contrast to girls, older boys are more are more willing to seek help less from others than younger boys. For boys, there was no relationship between seeking help from a counselor and age. A relationship between being involved in school activities and seeking help from a counselor was found, but the relationship was opposite for girls and boys. Girls who are more involved in school activities appeared seek help from counselors more than girls who are less involved, whereas boys that are less involved seek more help from counselors than boys who are more involved boys. Other relationships were also examined, including the relationship between students\u27 self-image, academic performance, school activity involvement, and students\u27 age

    Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

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    Lawson criterion for ignition exceeded in an inertial fusion experiment

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    For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

    Demonstration of Ignition Radiation Temperatures in Indirect-Drive Inertial Confinement Fusion Hohlraums

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    High resolution dynamic ocean topography in the Southern Ocean from GOCE

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    A mean dynamic ocean topography (MDT) has been computed using a high resolution GOCE (Gravity field and steady-state Ocean Circulation Explorer) gravity model and a new mean sea surface obtained from a combination of satellite altimetry covering the period 1992 October till 2010 April. The considered gravity model is GO-CONS-GCF-2-TIM-R3, which computes geoid using 12 months of GOCE gravity field data. The GOCE gravity data allow for more detailed and accurate estimates of MDT. This is illustrated in the Southern Ocean where the commission error is reduced from 20 to 5cm compared to the MDT computed using the GRACE gravity field model ITG-Grace2010. As a result of the more detailed and accurate MDT, the calculation of geostrophic velocities from the MDT is now possible with higher accuracy and spatial resolution, and the error estimate is about 7 cms−1 for the Southern Ocean

    Atg9 establishes Atg2-dependent contact sites between the endoplasmic reticulum and phagophores

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    The autophagy-related (Atg) proteins play a key role in the formation of autophagosomes, the hallmark of autophagy. The function of the cluster composed by Atg2, Atg18, and transmembrane Atg9 is completely unknown despite their importance in autophagy. In this study, we provide insights into the molecular role of these proteins by identifying and characterizing Atg2 point mutants impaired in Atg9 binding. We show that Atg2 associates to autophagosomal membranes through lipid binding and independently from Atg9. Its interaction with Atg9, however, is key for Atg2 confinement to the growing phagophore extremities and subsequent association of Atg18. Assembly of the Atg9-Atg2-Atg18 complex is important to establish phagophore-endoplasmic reticulum (ER) contact sites. In turn, disruption of the Atg2-Atg9 interaction leads to an aberrant topological distribution of both Atg2 and ER contact sites on forming phagophores, which severely impairs autophagy. Altogether, our data shed light in the interrelationship between Atg9, Atg2, and Atg18 and highlight the possible functional relevance of the phagophore-ER contact sites in phagophore expansion
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