The effects of the COD:P ratio on laboratory activated sludge systems

Laboratory activated sludge systems were operated at various COD:P ratios to study the effects of the influent phosphorus concentration on COD removal efficiency, cellular phosphorus, carbohydrate and protein contents, and alkaline phosphatase activity. In varying the COD:P ratio, the COD was held constant at 1000 mg l⁻¹ and phosphorus concentrations of 1, 2, 3, 5, 7, 9, 10, 20, 35 and 50 mg l⁻¹ were used. The optimum COD:P ratio for this study was found to be 100:1. Increasing the phosphorus concentration in the influent above one percent of the influent COD did not provide for an increase in the COD removal nor for significant changes in the cellular protein and carbohydrate content or the alkaline phosphatase activity.     

A validity study of functionally-based behavioral consultation with students with emotional/behavioral disabilities.

Eighteen students (K-11th grade) with emotional/behavioral disorders who were at-risk for change of placement to more restrictive settings participated. Construct validity of functional behavioral assessment (FBA) was assessed with a multifunction-multimethod matrix that showed excellent convergent and divergent agreement with combined FBA methods and functional analysis results. Treatment validity was assessed with random assignment to either a FBA with consultation condition (FBC) or to a behavioral consultation without FBA condition (BC). Growth curve analysis showed a significant decrease in inappropriate behavior from baseline to treatment for both treatment groups compared to a control group. The efficiency of teachers' implementation effected treatment validity. Effect sizes showed that regardless of treatment condition that interventions with good fidelity realized the largest effect (d = -1.14). Social and habilitative validity was assessed with telephone interviews conducted a year after treatment. Sixty-five percent attributed the students' problem behaviors to their thoughts or feelings, whereas only 25% attributed it to classroom variables. Many (57%) indicated the most helpful intervention would be individual counseling, whereas only 14% indicated a more involved classroom management plan would be useful. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Young and older emotional faces: Are there age group differences in expression identification and memory?

Studies have found that older compared with young adults are less able to identify facial expressions and have worse memory for negative than for positive faces, but those studies have used only young faces. Studies finding that both age groups are more accurate at recognizing faces of their own than other ages have used mostly neutral faces. Thus, age differences in processing faces may not extend to older faces, and preferential memory for own age faces may not extend to emotional faces. To investigate these possibilities, young and older participants viewed young and older faces presented either with happy, angry, or neutral expressions; participants identified the expressions displayed and then completed a surprise face recognition task. Older compared with young participants were less able to identify expressions of angry young and older faces and (based on participants’ categorizations) remembered angry faces less well than happy faces. There was no evidence of an own age bias in memory, but self-reported frequency of contact with young and older adults and awareness of own emotions played a role in expression identification of and memory for young and older faces. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Long-term memory for the terrorist attack of September 11: Flashbulb memories, event memories, and the factors that influence their retention.

More than 3,000 individuals from 7 U.S. cities reported on their memories of learning of the terrorist attacks of September 11, as well as details about the attack, 1 week, 11 months, and/or 35 months after the assault. Some studies of flashbulb memories examining long-term retention show slowing in the rate of forgetting after a year, whereas others demonstrate accelerated forgetting. This article indicates that (a) the rate of forgetting for flashbulb memories and event memory (memory for details about the event itself) slows after a year, (b) the strong emotional reactions elicited by flashbulb events are remembered poorly, worse than nonemotional features such as where and from whom one learned of the attack, and (c) the content of flashbulb and event memories stabilizes after a year. The results are discussed in terms of community memory practices. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging and reflective processes of working memory: Binding and test load deficits.

It was hypothesized that age-related deficits in episodic memory for feature combinations (e.g., B. L. Chalfonte & M. K. Johnson, 1996) signal, in part, decrements in the efficacy of reflective component processes (e.g., M. K. Johnson, 1992) that support the short-term maintenance and manipulation of information during encoding (e.g., F. I. M. Craik, R. G. Morris, & M. L. Gick, 1990; T. A. Salthouse, 1990). Consistent with this, age-related binding deficits in a working memory task were found in 2 experiments. Evidence for an age-related test load deficit was also found: Older adults had greater difficulty than young adults when tested on 2 features rather than 1, even when binding was not required. Thus, disruption of source memory in older adults may involve deficits in both encoding processes (binding deficits) and monitoring processes (difficulty accessing multiple features, evaluating them, or both). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of relatedness and number of distractors on attribute judgments in Alzheimer's disease.

Participants made judgments about the relative salience of category exemplars (e.g., fruit: apple or grape) or parts (e.g., plane: wings or seats). Mildly affected Alzheimer's disease (AD) patients were as accurate but slower than normal controls, and their response times increased more for related (e.g., apple, grape, or fig) than unrelated (e.g., apple, gym, bandit) choices as the number of alternatives was increased from 2 to 3. Performance (accuracy and response times) of moderate-severely affected patients was poorer still, but number of distractors and relatedness did not interact. In combination with previous findings (e.g., M. K. Johnson, A. M. Hermann, & J. L. Bonilla, 1995), these results suggest that the reflective processes necessary for deciding among competing alternatives show disruption early in the disease process. Such processing deficits would compound any difficulties arising from a degrading semantic structure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adapting instruction to the cognitive demands of learning to program.

This study investigated how instructional practices influence what students learn in Pascal programming classes. The study contrasted 8 introductory and 8 Advanced Placement (AP) level courses because goals of teachers, classroom activities, and assigned tasks differ. Introductory students primarily learn syntax and AP students learn to plan and debug complex problems. These differing cognitive demands would seem to require different instructional practices. In order to establish instructional practices, students reported teaching strategies, course structure, and classroom resources. To demonstrate programming proficiency, students modified and analyzed a computer program. Programming proficiency varied as a function of instructional practices and class level. Introductory students benefited from direct instruction, and AP students performed better with less direct guidance and more opportunities for autonomy. Characteristics of effective programming instruction vary depending on the cognitive demands of courses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Facial expression in adults with Down's Syndrome.

The facial expressions of adults with Down's syndrome (DS; n?=?15) as they watched happy, sad, and neutral videotapes were compared with those of a healthy age-matched control group (n?=?20). Facial movements were analyzed with the Facial Action Coding System (P. E. Ekman & W. V. Friesen, 1978). While watching happy stimuli, the 10 DS adults who were able to appropriately rate their reactions smiled with a cheek raise as frequently as control adults, suggesting that the expression of positive affect in these individuals is normal. Contrary to predictions, however, the DS group exhibited fewer smiles without cheek raises than did control adults and were more likely not to smile. Neither group showed prototypic sad facial expressions in response to sad stimuli. Independent of emotion, DS participants made more facial movements, including more tongue shows, than did control participants. Differences in facial expression in DS adults may confuse others' interpretations of their emotional responses and may be important for understanding the development of abnormal emotional processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Power and conflict resolution in sibling, parent–child, and spousal negotiations.

This study used a within-family observational design to examine conflict strategies (planning, opposition) and resolutions (standoff, win-loss, compromise) across family subsystems, with an emphasis on power differences between parents and children during relatively symmetrical within-generation (spousal, sibling) and relatively asymmetrical between-generation (parent–child) dyadic interactions. Up to six dyads in 67 families (children's ages ranging from 3 to 12 years) discussed an unresolved conflict. Results revealed that within-generation discussions ended more in standoff, whereas between-generation discussions ended with more win-loss resolutions. Multilevel analyses indicated that parents engaged in more planning and opposition than children; however, they opposed more and planned less with their spouses than their children. In general, more planning and less opposition were associated with achieving resolutions rather than failing to resolve differences. Some effects were qualified by within-family differences between mothers versus fathers and older versus younger siblings, as well as between-family differences in younger siblings' age. Implications for theories of power and family relationship dynamics are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)