Grain Floatation During Equiaxed Solidification of an Al-Cu Alloy in a Side-Cooled Cavity: Part I—Experimental Studies

Experimental studies were performed to investigate the role and influence of grain movement on macrosegregation and microstructure evolution during equiaxed solidification. Casting experiments were performed with a grain-refined Al-Cu alloy in a rectangular sand mold. For the aluminum alloy studied, the equiaxed grains are lighter than the bulk melt and thus float up. Experiments were designed to investigate floatation phenomena of equiaxed grains in the presence of thermosolutal convection. Cooling curves were recorded at key locations in both the casting and the chill. Quantitative image analysis and spatial chemical analysis were performed on the solidified casting to observe the chemical and microstructural inhomogeneity created by the melt convection and solid floatation. Several notable features that can be attributed to grain movement were observed in temperature histories, macrosegregation patterns, and microstructures. In our experiments, the floatation of grains influences the thermal conditions and the overall flow direction in the casting cavity. In some cases, the induced flow resulting from the grain movement caused a flow reversal. This in turn influences the solidification direction, microstructure evolution, and the overall macrosegregation behavior.     

Alarm reaction in acquisition and social transmission of simulated-predator recognition by zebra danio fish (Brachydanio rerio).

Alarm reactions occur in response to alarm substance passively released by injury to skin of zebra danio fish (Brachydanio rerio). Visual observation of alarmed conspecifics yields socially facilitated alarm by observers. Concurrent exposure of fish to alarm substance and a novel odorant (morpholine) later produced learned alarm to morpholine alone. Fish trained with morpholine plus alarm substance were mixed in with naive fish for a test with morpholine alone. The naive fish, separated out from the mixed groups, then demonstrated not only an acquired alarm reaction to morpholine but also an ability to communicate the acquired recognition of a simulated predator to a new group of naive observers. The results suggest the operation of a sophisticated antipredator defensive system in zebra danios that involves unlearned releasing stimuli, social facilitation, visual communication, learned predator recognition, and social communication of predator recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social cognition and the manic defense: Attributions, selective attention, and self-schema in bipolar affective disorder.

Manic patients, depressed bipolar patients, and normal controls were compared on measures of social cognition. Manic patients showed a normal self-serving bias on the Attributional Style Questionnaire, but depressed patients attributed negative events more than positive events to self. On an implicit test of attributional style, both patient groups attributed negative events more than positive events to self. Both patient groups showed slowed color naming for depression-related but not euphoria-related words. Manic patients, like normal controls, endorsed mainly positive words as true of self but, like the depressed patients, recalled mainly negative words. Findings from the implicit tests indicate a common form of psychological organization in manic and depressed patients, whereas the contrasts between the scores on the implicit and explicit measures are consistent with the hypothesis of a manic defense. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling heterogeneity in social interaction processes using multilevel survival analysis.

More than 15 years ago, survival or hazard regression analyses were introduced to psychology (W. Gardner & W. A. Griffin, 1989; W. A. Griffin & W. Gardner, 1989) as powerful methodological tools for studying real time social interaction processes among dyads. Almost no additional published applications have appeared, although such data are commonly collected and the applicable questions are central to many important theoretical perspectives. To revisit the basic methods, the authors use an example from emotion regulation theory in which the level of child antisocial behavior is hypothesized to be positively associated with the hazard rate of angry emotions and negatively associated with sad, fearful emotions in the face of parental negative behavior (scolding). The authors discuss the limitations of traditional approaches to the analysis of social interaction and demonstrate improvements in the ability to model individual differences now available in existing software. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The ability of the Millon Clinical Multiaxial Inventory--Third Edition to detect malingering.

This study investigated the ability of the Millon Clinical Multiaxial Inventory--Third Edition (MCMI-III) to discriminate students malingering psychopathology (n=106) from bona fide psychiatric inpatients (n=202). Students were randomly assigned to a fake-bad or an honest-responding condition. Analyses investigated the ability of the modifier indices to discriminate fake-bad group participants from the psychiatric inpatients. Scale X raw cutoff score >178 yielded a positive predictive power (PPP) of 0.0, a negative predictive power (NPP) of 63.1, and a hit rate of 63.1%. Optimal cutoff scores were developed. Scale X Base Rate (BR) >84 provided a PPP of 55.6, an NPP of 72.1, and a hit rate of 65.2%. Scale Y BR     

Studies of equipment response to low energy, low velocity, high amplitude and high frequency seismic events

The Leroy, Ohio earthquake occurred on January 31, 1986, with an estimated M_big magnitude of 5.0. Two power plants are located within 20 km of the epicenter area. This event was recorded at one of the two power plants. The recorded data were used to confirm the mathematical model and damping values used in design. The recorded event had high frequency, high acceleration, but low velocity and small displacement. The calculated response spectra from the records are well enveloped by the power plant design response spectra except around the 20 Hz region. Power plant equipment and structures were inspected and no earthquake induced damage was reported. Conservative analytical examination of the passive and the potentially most sensitive active safety related equipment revealed adequate margins against design allowables.Appendix A of Title 10, Part 100 of Code of Federal Regulations (10 CFR 100) requires plant shutdown for inspection in case of Operating Basis Earthquake (OBE) exceedance. The experience gained from the January 31, 1986, Leroy, Ohio earthquake is that plants should continue operating in case of spectra exceedance that are only in the high frequency region as was the case at Perry. As a lower bound guideline, if recorded earthquake duration is less than one second and the recorded maximum velocity and displacement at the foundation level are equal to or less than 2.54 cm/s and 0.2 cm respectively, based on the Perry experience the plant should continue to operate. At this level of earthquake motions, the amount of energy transferred to plant structures, systems and components is considered non-damaging to engineered items. These lower bound guidelines could be raised after additional analysis.     

Distinctiveness and Correlation in Conceptual Structure: Behavioral and Computational Studies.

Patients with category-specific deficits have motivated a range of hypotheses about the structure of the conceptual system. One class of models claims that apparent category dissociations emerge from the internal structure of concepts rather than fractionation of the system into separate substores. This account claims that distinctive properties of concepts in the living domain are vulnerable because of their weak correlation with other features. Given the assumption that mutual activation among correlated properties produces faster activation in the normal system, the authors predicted a disadvantage for the distinctive features of living things for unimpaired adults. Results of a speeded feature verification study supported this prediction, as did a computational simulation in which networks mapped from orthography to semantics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Antioxidant potential and content of phenolic compounds in extracts of twelve selected Malaysian commercial wood species

This study was performed to investigate the antioxidant values of twelve selected Malaysian wood species. Bark and heartwood were extracted with toluene: industrial methylated spirit (Tol: IMS) and evaluated for antioxidant activity. Folin–Ciocalteu reagent was used to determine the total antioxidant activity and total phenols of plant extracts. Free radical scavenging activity was evaluated using 2,2-dipheny-2-picrylhydrazyl (DPPH). Extractive yields, antioxidant activity and total phenolic content varied among wood species. N. heimii had the highest extractive yields (23.50 and 9.16 %), antioxidant (93.60 and 83.78 %) and total phenolic content (29.11 and 24.11 mgGAE/g) for bark and heartwood, respectively. The results provided promising evidence that those tropical timbers may be useful as potential sources of natural antioxidants and could be used as drug formulations.     

Design through making: crafts knowledge as facilitator to collaborative new product development

Collaboration between manufacturers and craft makers is believed by many crafts theorists to offer new originality, insight and specialist expertise to design for production. In practice, however, there exists a discrepancy between this ideal and a reality of unreconcilable cultural and methodological differences. This paper documents and discusses such a collaboration as an example of best practice with implications for managers, educators, designers and craft makers. It identifies a new role for craft makers with the appropriate knowledge and experience to act as bridges within companies, facilitating the adoption of design methodologies appropriate to changing priorities in the manufacturing industries.