Overcoming contextual limitations on problem-solving transfer.

Five experiments investigated transfer from multiple analogs to a superficially dissimilar target problem. When subjects explicitly compared the analogs and then immediately attempted to solve the target problem in the context of a single experiment, transfer was obtained with significant frequency even without a hint that the analogs and target were related. Prehint transfer was sharply reduced or eliminated when the source analogs and the target were presented in different contexts, even when the transfer test was immediate. However, prehint transfer was enhanced, even after a context shift and a week-long delay between reading the source analogs and solving the problem, when the following conditions were met: The target problem was reworded slightly to emphasize a structural feature that it shared with the analogs; three rather than two source analogs were provided; and detailed, schema-oriented questions were used to help subjects focus on the problem-relevant aspects of the stories. Although spontaneous transfer between small numbers of dissimilar analogs is difficult to obtain, it can be achieved by manipulations that foster abstraction of a problem schema from the training examples. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The subgoal learning model: Creating better examples so that students can solve novel problems.

Learners have great difficulty solving problems requiring changes to solutions demonstrated in examples. However, if the solution procedures learners form are organized by subgoals, then they are more successful. Subgoal learning is hypothesized to be aided by cues in example solutions that indicate that certain steps go together. These cues may induce a learner to attempt to self-explain the purpose of the steps, resulting in the formation of a subgoal. Across 4 experiments it was found that a label for a group of steps in examples helped participants form subgoals as assessed by measures such as problem-solving performance and talk aloud protocols. Abstract labels were more likely than superficial labels to lead participants to form subgoals with fewer ties to surface features. Subgoals guide problem solving by helping learners focus on the steps to modify in novel problems that involve the same subgoals but require new steps to achieve them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Improved Time-Resolved Measurements of Inorganic Ions in Particulate Matter by PILS-IC Integrated with a Sample Pre-Concentration System

A particle-into-liquid sampler coupled with ion chromatograph (PILS-IC) for the on-line measurement of inorganic ions has been modified by the insertion of two ion-exchange pre-concentration cartridges that enrich the sample during the period of the IC analysis. The limits of detection of the modified instrument were 10-15 times lower and the time coverage 24 times higher (from 2 to 48 min per hour) than those of the original PILS-IC setup. The instrumental performance in terms of recovery and break-through volume from the cartridges was satisfactory. The modified PILS-IC was operated in comparison with a diffusion denuder line and with a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS) during a short intensive measurement period organized in the framework of the European Monitoring and Evaluation Programme (EMEP), a co-operative program for monitoring and evaluation of the long-range transmission of the air pollutants in Europe. The instrument showed a quantitative response in agreement with the results of the diffusion lines, and an ability to trace fine concentration variations not so different from the performance of the much more complex HR-TOF-AMS. From the time patterns of the ion concentrations measured by the modified PILS-IC, it was possible to obtain useful information about the variations in the air quality and in the strength of the particulate matter sources.

Copyright 2015 American Association for Aerosol Research     

Aiding Transfer in Statistics: Examining the Use of Conceptually Oriented Equations and Elaborations During Subgoal Learning.

Consistent with a subgoal-learning approach, the authors hypothesized that learners who studied statistics examples with conceptually oriented equations would transfer more successfully to novel problems compared with learners who studied examples using computationally oriented equations. The conceptually oriented equations were designed to capture the relationship between the concept and its computation, whereas the computationally oriented equations were designed to simplify calculations. This hypothesis was supported across 2 experiments. The authors also examined the implications of providing learners with elaborations of the procedures illustrated in the examples either before or after they studied them. The location of the elaborations had no apparent effect. Overall, these results demonstrate that solution procedures organized around appropriate conceptually oriented subgoals are easier to adapt for novel problems than procedures built around computationally friendly, but conceptually opaque, steps. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social facilitation effects of virtual humans

OBJECTIVE: To investigate whether virtual humans produce social facilitation effects. BACKGROUND: When people do an easy task and another person is nearby, they tend to do that task better than when they are alone. Conversely, when people do a hard task and another person is nearby, they tend to do that task less well than when they are alone. This phenomenon is referred to in the social psychology literature as social facilitation. The present study investigated whether virtual humans can evoke a social facilitation response. METHOD: Participants were given different tasks to do that varied in difficulty. The tasks involved anagrams, mazes, and modular arithmetic. They did the tasks alone, in the company of another person, or in the company of a virtual human on a computer screen. RESULTS: For easy tasks, performance in the virtual human condition was better than in the alone condition, and for difficult tasks, performance in the virtual human condition was worse than in the alone condition. CONCLUSION: As with a human, virtual humans can produce social facilitation. APPLICATION: The results suggest that designers of virtual humans should be mindful about the social nature of virtual humans; a design decision as to when and how to present a virtual human should be a deliberate and informed decision. An ever-present virtual human might make learning and performance difficult for challenging tasks.     

Fulvic acid in microlayer waters of the Gerlache Inlet Sea (Antarctica): their distribution in dissolved and particulate phases

In this work we studied the distribution of humic compounds between microlayer and subsurface waters. Both dissolved (DFA) and particulate (PFA) matter were considered. Humic acids were not found. The amount of total particulate matter is the same both in microlayer and subsurface waters. Conversely, particulate organic matter and fulvic acid concentrations were greater in microlayer waters. Enrichment factors (microlayer PFA/subsurface PFA and microlayer DFA/subsurface DFA) show a greater presence of fulvic acids in the microlayer. Moreover, the enrichment process is greater for the particulate phase. C/N values both in microlayer and subsurface waters are greater for DFA with respect to PFA and C/N values for DFA of microlayer are greater than that of subsurface waters. So DFA could be older than PFA, and DFA of subsurface waters younger than that of microlayer waters. For PFA S/C ratios in microlayer waters are greater than that of subsurface waters, underlining that the enrichment process is selective as regards sulphur-containing structures.     

The effects of surface and structural feature matches on the access of story analogs.

Competing theories of analogical reasoning have disagreed on the relative contributions of surface and structural features to the access of previously read base stories when one is reading a current cue story. A key limitation of the prior work was that surface and structural feature overlap between bases and cues was not manipulated precisely. The present study systematically manipulated the number of surface and structural matches to determine their relative effect on access. Results involving reminding and reading time measures suggest that surface and lower-order structural features affected access about equally, at least when a higher-order relation (HOR) was shared between a base and cue story. When a HOR was not shared, surface feature overlap continued to affect access while lower-order structural features had a less reliable effect. Models of access might need to be adjusted to account for these phenomena. (PsycINFO Database Record (c) 2011 APA, all rights reserved)