Guilty by association: When one's group has a negative history.

The impact of the history of one's own group's treatment of another group on feelings of collective guilt and behavioral reactions to this guilt were examined in 2 studies. In a laboratory experiment it was shown that it is possible to elicit feelings of group-based guilt and that those are distinct from feelings of personal guilt. In a 2nd study, a field experiment, low-identified group members acknowledged the negative aspects of their own nation's history and felt more guilt compared with high identifiers when both negative and positive aspects of their nation's history were made salient. Perceptions of intragroup variability and out-group compensation closely paralleled the interactive pattern on guilt. Links between social identity theory and the experience of specific emotions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

30μm Heterodyne receiver

Advantages and constraints of remote measurements using heterodyne spectroscopy near 30 μm are discussed. The state of the art of wideband HgCdTe photomixers and PbSnSe diode laser local oscillators being developed for far infrared heterodyne receivers is described. The first compact 30 μm heterodyne radiometer was built and initial results at 28 μm show about 2% mixer efficiency for a 500 MHz bandwidth receiver. Factors limiting receiver performance are discussed, along with the projected sensitivity of new interdigitated-electrode HgCdTe photoconductor mixers being developed for operation up to 200 μm.     

Distributed, Physics-Based Control of Swarms of Vehicles

We introduce a framework, called “physicomimetics,” that provides distributed control of large collections of mobile physical agents in sensor networks. The agents sense and react to virtual forces, which are motivated by natural physics laws. Thus, physicomimetics is founded upon solid scientific principles. Furthermore, this framework provides an effective basis for self-organization, fault-tolerance, and self-repair. Three primary factors distinguish our framework from others that are related: an emphasis on minimality (e.g., cost effectiveness of large numbers of agents implies a need for expendable platforms with few sensors), ease of implementation, and run-time efficiency. Examples are shown of how this framework has been applied to construct various regular geometric lattice configurations (distributed sensing grids), as well as dynamic behavior for perimeter defense and surveillance. Analyses are provided that facilitate system understanding and predictability, including both qualitative and quantitative analyses of potential energy and a system phase transition. Physicomimetics has been implemented both in simulation and on a team of seven mobile robots. Specifics of the robotic embodiment are presented in the paper.     

Effects of copper deficiency and copper deficiency coupled with high dietary iron or molybdenum on phagocytic cell function and response of calves to a respiratory disease challenge

A study was conducted to determine the effects of supplementing a diet marginally deficient in copper (Cu) with iron (Fe), molybdenum (Mo), or Cu on phagocytic cell function and disease resistance of calves. Thirty-one calves were born to heifers fed a corn silage-based diet containing 4.5 mg of Cu/kg. Treatments consisted of 1) control (CON; no supplemental Cu, Fe, or Mo), 2) 600 mg of Fe added/kg (FE), 3) 5 mg of Mo added/kg (MO), or 4) 10 mg of Cu added/kg of DM (CU). Activity of superoxide dismutase was lower (P < .06) in neutrophils from MO vs CON or CU calves at 170 d of age. bactericidal activity of neutrophils from MO calves tended (P = .15) to be lower compared with those from CU calves at 70 d of age. Calves were inoculated intranasally with live infectious bovine rhinotracheitis virus (IBRV) 2 d after weaning, followed by intratracheal administration of Pasteurella hemolytica 5 d later. Iron- and Cu-supplemented calves exhibited higher (P < .01) body temperatures and lower (P < .06) feed intakes following IBRV inoculation compared with CON and MO calves. Copper-supplemented calves had higher levels of plasma tumor necrosis factor (TNF) than MO calves at weaning (P < .05) and tended to have higher plasma TNF (P = .11) than FE and MO calves 5 d after IBRV inoculation. These data indicate that dietary levels of Mo and Cu can affect body temperature and feed intake responses to disease by affecting TNF and perhaps other cytokines.     

Transfection of wild-type but not mutant p53 induces early monocytic differentiation in HL60 cells and increases their sensitivity to stress

HL60 cells, which lack the p53 gene due to a deletion, were used as an in vitro model system to study the effect of wild-type p53 gene expression on hematopoietic differentiation. We transfected HL60 cells with wild-type p53 and two mutant p53 cDNAs encoding the Val to Ala mutation at codon 143 and the Arg to Trp mutation at codon 248. Flow cytometry, growth, and cytochemical analysis for alpha-napthyl butyrate esterase activity and nitroblue tetrazolium reduction indicated that wild-type p53 but not mutant p53 induced early monocytic differentiation in the transfected HL60 cells without terminal growth arrest. The wild-type p53 transfectants did not differentiate along the granulocytic pathway, even when induced with 1.25% DMSO for 6 days; rather, these cells resembled monocytic cells, confirming that wild-type p53 transfection caused these cells to become committed to differentiate along the monocytic pathway. HL60 cells transfected with wild-type p53 were more sensitive to stress, such as growth in serum-depleted medium and exposure to a chemotherapeutic agent, etoposide.     

Pyrite oxidation in Lower Lias Clay at concrete highway structures affected by thaumasite, Gloucestershire, UK

The process of pyrite oxidation with the resulting formation of sulfates in disturbed pyrite-rich mudstone is recognised in the UK as a potential engineering hazard. This paper describes and quantifies the extent of pyrite oxidation in Lower Lias Clay in Gloucestershire using a large data set collected in 1998 and 1999 during the investigation of twenty-eight, approximately 30-year old highway structures affected by the thaumasite form of sulfate attack. Most of the structures have concrete spread footings founded on undisturbed and relatively unweathered Lower Lias Clay, and are surrounded by backfill of reworked Lower Lias Clay. Chemical, X-ray diffraction and X-ray fluorescence analyses are used to determine the composition of the soils. Differences are identified in the sulfides, sulfates and total sulfur concentrations between unweathered and weathered Lower Lias Clay and the backfill. The work is supported by pyrite oxidation trials in the laboratory on clay samples stored in bags and sealed tubes. The results indicate that pyrite oxidation, sulfate formation and leaching have occurred as the Lower Lias Clay weathers in situ and also during and following disturbance and reworking for highway construction. The amount and rate of pyrite oxidation are estimated, and comparison is made with the concentration of sulfate in the surrounding groundwater, and the extent of thaumasite sulfate attack measured at adjacent structures.     

Feeding a low manganese diet to heifers during gestation impairs fetal growth and development

A study was conducted to examine the effects of low dietary Mn on growth performance of pregnant heifers and fetal development of their offspring. Twenty pregnant Angus (n = 9) and Simmental (n = 11) heifers averaging 17 mo of age and 447.6 kg of initial body weight were used in the 267-d study. Heifers were selected from a previous study examining the effects of supplemental Mn on growth and reproductive performance of heifers. Ten pregnant heifers per treatment from the control (analyzed at 15.8 mg of Mn/kg of DM) and supplemental Mn (50 mg/kg of DM) treatments were randomly selected at the conclusion of the previous study to continue on their respective dietary treatments through gestation and early lactation. Serum cholesterol for the 267-d period was not affected by treatment. Whole-blood Mn concentration of heifers on d 267 was not affected by treatment. Whole-blood Mn concentration at birth was lower in calves born to control heifers than in those born to supplemented heifers. Calves born to control heifers weighed less at birth than those born to heifers receiving supplemental Mn. Calves born to control heifers suffered from varying signs of Mn deficiency, including superior brachygnathism, unsteadiness, disproportionate dwarfism, and swollen joints. Results suggest that feeding gestating heifers a diet containing 16.6 mg of Mn/kg of DM is not adequate for proper fetal development. Supplementation of 50 mg of Mn/kg of DM to the control diet was sufficient to overcome any signs of Mn deficiency in calves.