Protective Factors in Preventing Adolescent Alcohol Abuse

Recent data suggests that the decrease of risk factors and the increase of protective factors relating to adolescent alcohol abuse will aid in the resilience of adolescents and prevent alcohol use. The purpose of this study was to interview several suburban school district support staff on what they understand the protective factors to be with young people they work with in individual schools. It was determined that, although parental influence has the greatest impact on adolescent alcohol use, school support staff can and do nurture and positively impact the reduction of adolescent alcohol use

Reading First Impact Study: Interim Report

This report, written by Abt Associates and MDRC and published by the U.S. Department of Education's Institute of Education Sciences, finds that Reading First increased the amount of time that teachers spent on the five essential components of reading instruction, as defined by the National Reading Panel. While Reading First did not improve students' reading comprehension on average, there are some indications that some sites had impacts on both instruction and reading comprehension. An overview puts these interim findings in context

PREDATOR PRESENCE AND SIZE VARIATION ALTERS COMMUNITY STRUCTURE THROUGH MULTIPLE TROPHIC CASCADES

Predation plays a crucial role in shaping community structure and can initiate trophic cascades that can alter abundances across adjacent trophic levels. Recent research has suggested that variation among individual predators may have stronger effects on ecological dynamics than previously appreciated. Intraspecific variation within predators could lead to differential levels of top-down control with implications for trophic cascade strength. In this experiment, we manipulated the body size variation of predatory mole salamanders (Ambystoma talpoideum) within experimental mesocosms and monitored a suite of abiotic and biotic response variables. We predicted that predator populations with increased body size variation would have limited top-down control due to weaker interactions with a greater number of prey species. Conversely, we predicted that populations with similarly sized predators would have strong control over fewer prey species. Salamander presence affected nearly every biotic parameter measured, suppressing some populations (e.g. invertebrate predators) and facilitating others (e.g. invertebrate collectors), triggering multiple trophic cascades. A few invertebrate taxa responded to variation in predator body size and in nearly all of these instances, taxa responded more strongly to treatments with increased body size variation than in treatments with similarly-sized predators. Predator size variation may promote individual dietary specialization by differently sized predators, resulting in strong control of focal prey. These results demonstrate that predators have pervasive effects on all trophic levels of a community regardless of size structure, and that when size structure has an effect on abundances of particular taxa, increased body size variation can lead to stronger top-down control

Entrapment: an important mechanism to explain the shortwave 3D radiative effect of clouds

Several mechanisms have previously been proposed to explain differences between the shortwave reflectance of realistic cloud scenes computed using the 1D independent column approximation (ICA) and 3D solutions of the radiative transfer equation. When the sun is low in the sky, interception of sunlight by cloud sides tends to increase reflectance relative to ICA estimates that neglect this effect. When the sun is high, 3D radiative transfer tends to make clouds less reflective, which we argue is explained by the mechanism of “entrapment” whereby horizontal transport of radiation beneath a cloud layer increases the chances, relative to the ICA, of light being absorbed by cloud or the surface. It is especially important for multilayered cloud scenes. We describe modifications to the previously described Speedy Algorithm for Radiative Transfer through Cloud Sides (SPARTACUS) to represent different entrapment assumptions, and test their impact on 65 contrasting scenes from a cloud-resolving model. When entrapment is represented explicitly via a calculation of the mean horizontal distance traveled by reflected light, SPARTACUS predicts a mean “3D radiative effect” (the difference in top-of-atmosphere irradiances between 3D and ICA calculations) of 8.1 W m−2 for overhead sun. This is within 2% of broadband Monte Carlo calculations on the same scenes. The importance of entrapment is highlighted by the finding that the extreme assumptions in SPARTACUS of “zero entrapment” and “maximum entrapment” lead to corresponding mean 3D radiative effects of 1.7 and 19.6 W m−2, respectively