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Author (up) Aronson, J.; Fried, C.B.; Good, C. file  url
  Title Reducing the Effects of Stereotype Threat on African American College Students by Shaping Theories of Intelligence Type Journal Article
  Year 2002 Publication Journal of Experimental Social Psychology Abbreviated Journal Journal of Experimental Social Psychology  
  Volume 38 Issue 2 Pages 113-125  
  Keywords African American; College students; Stereotypes; Stereotype threat; Academic performance; Grades  
  Abstract African American college students tend to obtain lower grades than their White counterparts, even when they enter college with equivalent test scores. Past research suggests that negative stereotypes impugning Black students' intellectual abilities play a role in this underperformance. Awareness of these stereotypes can psychologically threaten African Americans, a phenomenon known as “stereotype threat” (Steele & Aronson, 1995), which can in turn provoke responses that impair both academic performance and psychological engagement with academics. An experiment was performed to test a method of helping students resist these responses to stereotype threat. Specifically, students in the experimental condition of the experiment were encouraged to see intelligence “the object of the stereotype” as a malleable rather than fixed capacity. This mind-set was predicted to make students' performances less vulnerable to stereotype threat and help them maintain their psychological engagement with academics, both of which could help boost their college grades. Results were consistent with predictions. The African American students (and, to some degree, the White students) encouraged to view intelligence as malleable reported greater enjoyment of the academic process, greater academic engagement, and obtained higher grade point averages than their counterparts in two control groups.  
  Call Number Serial 1186  
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Author (up) Bak, T.; Nowotny, J.; Rekas, M.; Sorrell, C.C. file  url
  Title Photo-electrochemical hydrogen generation from water using solar energy. Materials-related aspects Type Journal Article
  Year 2002 Publication International Journal of Hydrogen Energy Abbreviated Journal International Journal of Hydrogen Energy  
  Volume 27 Issue 10 Pages 991-1022  
  Keywords Hydrogen generation; Photo-electrodes; Solar energy conversion; Photo-electrochemistry; Photo-cells; Semiconducting materials  
  Abstract The present work considers hydrogen generation from water using solar energy. The work is focused on the materials-related issues in the development of high-efficiency photo-electrochemical cells (PECs). The property requirements for photo-electrodes, in terms of semiconducting and electrochemical properties and their impact on the performance of PECs, are outlined. Different types of PECs are overviewed and the impact of the PEC structure and materials selection on the conversion efficiency of solar energy are considered.

Trends in research in the development of high-efficiency PECs are discussed. It is argued that very sophisticated materials engineering must be used for processing the materials that will satisfy the specific requirements for photo-electrodes. An important issue in the processing of these materials is the bulk vs. interface properties at the solid/solid interfaces (e.g., grain boundaries) and solid/liquid interfaces (e.g., electrode/electrolyte interface). Consequently, the development of PECs with the efficiency required for commercialization requires the application of up-to-date materials processing technology.

The performance of PECs is considered in terms of:

excitation of electron–hole pair in photo-electrodes;

charge separation in photo-electrodes;

electrode processes and related charge transfer within PECs;

generation of the PEC voltage required for water decomposition.

This work also gives empirical data on the performance of PECs of different structures and materials selection.

It is argued that PEC technology is the most promising technology for hydrogen production owing to several reasons:

PEC technology is based on solar energy, which is a perpetual source of energy, and water, which is a renewable resource;

PEC technology is environmentally safe, with no undesirable byproducts;

PEC technology may be used on both large and small scales;

PEC technology is relatively uncomplicated.

According to current predictions, the production of hydrogen will skyrocket by 2010 (Morgan and Sissine, Congressional Research Service, Report for Congress. The Committee for the National Institute for the Environment, Washington, DC, 20006-1401, 28 April 1995). Consequently, seed funding already has been allocated to several national research programs aiming at the development of hydrogen technology. The countries having access to this PEC technology are likely to form the OPEC of the future.
  Call Number Serial 1319  
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Author (up) Berzins, D.W.; Bundy, K.J. file  url
  Title Bioaccumulation of lead in Xenopus laevis tadpoles from water and sediment Type Journal Article
  Year 2002 Publication Environment International Abbreviated Journal Environ Int  
  Volume 28 Issue 1-2 Pages 69-77  
  Keywords Animals; Body Weight/drug effects; Environmental Pollutants/*pharmacokinetics/toxicity; Fresh Water/chemistry; Geologic Sediments/chemistry; Larva/*chemistry/growth & development; Lead/*pharmacokinetics/toxicity; Louisiana; *Xenopus  
  Abstract The overall objective of this research was to monitor the uptake kinetics of lead in an amphibian model and correlate metal content with embryo development. Based upon the concentration of lead found in the water and sediment of a Louisiana swamp adjacent to a Superfund site, a controlled laboratory experiment exploring lead uptake from water and sediment by Xenopus laevis tadpoles was conducted. For 5 weeks, tadpoles were exposed to water and a simulated sediment, kaolin, spiked with 1, 5, or 10 times the concentration of lead found in field water and sediment samples. Additionally, organisms were exposed to the 5 x condition for 3 and 6 weeks. The experimental controls consisted of unexposed tadpoles and ones exposed to lead originating from water or sediment exclusively. At the end of the exposure periods, developmental data, i.e., body weight and developmental stage, were recorded, and the tadpoles were analyzed for whole body lead concentration. Lead extraction was accomplished by dry ashing, and its amount was quantified polarographically. Results showed that lead inhibited the normal development of these amphibians, in a manner that generally was more severe as exposure level increased. The hindrance of tadpole development also coincided with an increase in whole body lead concentration at higher exposures. Temporally, at the 5 x exposure concentration, the mean lead level increased with time, but this difference was not statistically significant (P<.05). Additionally, control animals exposed to lead (either in water or in sediment) showed no statistical difference with regard to weight and lead uptake, indicating that lead originating from both water and sediment is incorporated into the tadpole. The controlled laboratory experimental protocol used here is thus capable of investigating the uptake of a single metal (Pb in this case) and determining its effect on the development of tadpoles while differentiating the significance of multiple sources of exposure.  
  Call Number Serial 1183  
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Author (up) Bhattacharya, R.; Beck, D.J. file  url
  Title Survival and SOS induction in cisplatin-treated Escherichia coli deficient in Pol II, RecBCD and RecFOR functions Type Journal Article
  Year 2002 Publication DNA Repair Abbreviated Journal DNA Repair (Amst)  
  Volume 1 Issue 11 Pages 955-966  
  Keywords Antineoplastic Agents/*pharmacology; Bacterial Proteins/physiology; Cell Division/drug effects/genetics/radiation effects; Cisplatin/*pharmacology; DNA Damage/drug effects/radiation effects; DNA Polymerase II/*physiology; DNA Polymerase III/physiology; DNA Repair/drug effects/radiation effects; DNA-Binding Proteins/physiology; Dose-Response Relationship, Drug; Drug Resistance, Bacterial/physiology; Escherichia coli/*drug effects/enzymology; Escherichia coli Proteins/pharmacology/*physiology; Exodeoxyribonuclease V; Exodeoxyribonucleases/*physiology; Lac Operon; SOS Response (Genetics)/*physiology; beta-Galactosidase/metabolism  
  Abstract Cisplatin is a potent anticancer agent forming intrastrand-crosslinks in DNA. The efficacy of cisplatin in chemotherapy can be limited by the development of tumor resistances such as elevated DNA repair or damage tolerance. In Escherichia coli, cisplatin treatment causes induction of the SOS regulon resulting in elevated levels of DNA Pol II, DNA Pol IV, DNA Pol V, the cell division inhibitor SfiA (SulA), homologous recombination (HR) and DNA repair. In this work, the roles of Pol II and HR in facilitating resistance of E. coli to cisplatin are studied. SOS induction levels were measured by beta-galactosidase assays in cisplatin-treated and untreated E. coli PQ30 that has the lacZ gene fused to the sfiA promoter. Comparative studies were carried out with derivatives of PQ30 constructed by P1 transduction that have transposon insertions in the polB gene, the recB gene blocking the RecBCD pathway of HR and genes of the RecFOR pathway of HR. Resistance of E. coli strains to cisplatin as determined by plating experiments decreased in the following order: parent PQ30 strain, polB > recO, recR, recF > recB. Both the RecBCD and RecFOR pathways of HR are important for survival when E. coli is exposed to cisplatin, because treatment of double mutants deficient in both pathways reduced colony forming ability to 37% in 6-9min in comparison to 39-120min for single mutants. Pol II and RecF appear to function in two distinct pathways to initiate replication blocked due to damage caused by cisplatin because function of Pol II was required for survival in mutants deficient in the RecFOR pathway after 2h of cisplatin treatment. In contrast, Pol II was not required for survival in recB mutants. SOS induction was delayed in RecFOR deficient mutants but occurred at high levels in the recB mutant soon after cisplatin treatment in a RecFOR-dependent way. An SfiA independent, DNA damage dependent pathway is apparently responsible for the filamentous cells observed after cisplatin or MMC treatments of these SfiA defective strains.  
  Call Number Serial 407  
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Author (up) Boomsma, D.; Busjahn, A.; Peltonen, L. file  url
  Title Classical twin studies and beyond Type Journal Article
  Year 2002 Publication Nature Reviews. Genetics Abbreviated Journal Nat Rev Genet  
  Volume 3 Issue 11 Pages 872-882  
  Keywords Female; Genetic Research; Humans; Male; Pedigree; *Twin Studies as Topic/methods  
  Abstract Twin studies have been a valuable source of information about the genetic basis of complex traits. To maximize the potential of twin studies, large, worldwide registers of data on twins and their relatives have been established. Here, we provide an overview of the current resources for twin research. These can be used to obtain insights into the genetic epidemiology of complex traits and diseases, to study the interaction of genotype with sex, age and lifestyle factors, and to study the causes of co-morbidity between traits and diseases. Because of their design, these registers offer unique opportunities for selected sampling for quantitative trait loci linkage and association studies.  
  Call Number Serial 1635  
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Author (up) Callaway, R.M.; Brooker, R.W.; Choler, P.; Kikvidze, Z.; Lortie, C.J.; Michalet, R.; Paolini, L.; Pugnaire, F.I.; Newingham, B.; Aschehoug, E.T.; Armas, C.; Kikodze, D.; Cook, B.J. file  url
  Title Positive interactions among alpine plants increase with stress Type Journal Article
  Year 2002 Publication Nature Abbreviated Journal Nature  
  Volume 417 Issue 6891 Pages 844-848  
  Keywords Atmospheric Pressure; Biomass; *Ecosystem; Geography; Plant Development; *Plant Physiological Phenomena; Reproduction; Species Specificity; Temperature; Stress  
  Abstract Plants can have positive effects on each other. For example, the accumulation of nutrients, provision of shade, amelioration of disturbance, or protection from herbivores by some species can enhance the performance of neighbouring species. Thus the notion that the distributions and abundances of plant species are independent of other species may be inadequate as a theoretical underpinning for understanding species coexistence and diversity. But there have been no large-scale experiments designed to examine the generality of positive interactions in plant communities and their importance relative to competition. Here we show that the biomass, growth and reproduction of alpine plant species are higher when other plants are nearby. In an experiment conducted in subalpine and alpine plant communities with 115 species in 11 different mountain ranges, we find that competition generally, but not exclusively, dominates interactions at lower elevations where conditions are less physically stressful. In contrast, at high elevations where abiotic stress is high the interactions among plants are predominantly positive. Furthermore, across all high and low sites positive interactions are more important at sites with low temperatures in the early summer, but competition prevails at warmer sites.  
  Call Number Serial 2154  
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Author (up) Carlini, V.P.; Monzon, M.E.; Varas, M.M.; Cragnolini, A.B.; Schioth, H.B.; Scimonelli, T.N.; de Barioglio, S.R. file  url
  Title Ghrelin increases anxiety-like behavior and memory retention in rats Type Journal Article
  Year 2002 Publication Biochemical and Biophysical Research Communications Abbreviated Journal Biochem Biophys Res Commun  
  Volume 299 Issue 5 Pages 739-743  
  Abstract Ghrelin is a peptide found in the hypothalamus and stomach that stimulates food intake and whose circulating concentrations are affected by nutritional state. Very little is known about other central behavioral effects of ghrelin, and thus, we investigated the effects of ghrelin on anxiety and memory retention. The peptide was injected intracerebroventricularly in rats and we performed open-field, plus-maze, and step-down tests (inhibitory avoidance). The administration of ghrelin increased freezing in the open field and decreased the number of entries into the open spaces and the time spent on the open arms in the plus-maze, indicating an anxiogenic effect. Moreover, the peptide increased in a dose-dependent manner the latency time in the step-down test. A rapid and prolonged increase in food intake was also observed. Our results indicate that ghrelin induces anxiogenesis in rats. Moreover, we show for the first time that ghrelin increases memory retention, suggesting that the peptide may influence processes in the hippocampus.

Subject Headings: Animals; *Anxiety; Appetite Regulation/drug effects; Behavior, Animal/drug effects; Dose-Response Relationship, Drug; Eating/drug effects; Ghrelin; Habituation, Psychophysiologic/drug effects; Locomotion/drug effects; Male; *Memory/drug effects; Peptide Hormones/*pharmacology/physiology; Rats; Rats, Wistar

Keywords: Ghrelin increases anxiety-like behavior and memory retention in rats
  Call Number Serial 2748  
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Author (up) Cavicchioli, R. file  url
  Title Extremophiles and the search for extraterrestrial life Type Journal Article
  Year 2002 Publication Astrobiology Abbreviated Journal Astrobiology  
  Volume 2 Issue 3 Pages 281-292  
  Abstract Extremophiles thrive in ice, boiling water, acid, the water core of nuclear reactors, salt crystals, and toxic waste and in a range of other extreme habitats that were previously thought to be inhospitable for life. Extremophiles include representatives of all three domains (Bacteria, Archaea, and Eucarya); however, the majority are microorganisms, and a high proportion of these are Archaea. Knowledge of extremophile habitats is expanding the number and types of extraterrestrial locations that may be targeted for exploration. In addition, contemporary biological studies are being fueled by the increasing availability of genome sequences and associated functional studies of extremophiles. This is leading to the identification of new biomarkers, an accurate assessment of cellular evolution, insight into the ability of microorganisms to survive in meteorites and during periods of global extinction, and knowledge of how to process and examine environmental samples to detect viable life forms. This paper evaluates extremophiles and extreme environments in the context of astrobiology and the search for extraterrestrial life.

Subject Headings: *Archaea; *Bacteria; Cold Temperature; *Eukaryotic Cells; *Exobiology; Genomics; Space Flight

Keywords: Extremophiles and the search for extraterrestrial life
  Call Number Serial 2508  
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Author (up) Citron, M. file  url
doi  openurl
  Title Alzheimer's disease: treatments in discovery and development Type Journal Article
  Year 2002 Publication Nature Neuroscience Abbreviated Journal Nat Neurosci  
  Volume 5 Suppl Issue Pages 1055-1057  
  Keywords Alzheimer Disease/metabolism/physiopathology/*therapy; Amyloid beta-Peptides/*antagonists & inhibitors/biosynthesis; Animals; Brain/*drug effects/metabolism/physiopathology; Disease Models, Animal; *Drug Design; Drug Evaluation/trends; Drug Industry/trends; Enzyme Inhibitors/pharmacology/therapeutic use; Humans  
  Abstract Alzheimer's disease is the single biggest unmet medical need in neurology. Current drugs are safe, but of limited benefit to most patients. This review discusses the scientific basis and current status of promising disease-modifying therapies in the discovery and development stages. I describe the major targets of anti-amyloid therapy and the main focus of disease modification approaches. In addition, two new potential treatment approaches supported by retrospective epidemiology are outlined.  
  Call Number Serial 137  
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Author (up) Clewell, B.C.; Campbell, P.B. file  url
  Title Taking Stock: Where We'Ve Been, Where We Are, Where We'Re Going Type Journal Article
  Year 2002 Publication Journal of Women and Minorities in Science and Engineering Abbreviated Journal J Women Minor Scien Eng  
  Volume 8 Issue 3-4 Pages 30  
  Abstract Focusing on “where we’ve been, where we are, and where we’re going,” the authors examine minority women’s and White women’s progress in science, mathematics, engineering, and technology (SMET) over the past decade. Starting from an exploration of participation and achievement data, the authors move on to cover the theories behind SMET gender differences, including those based on testing, biology, social-psychology, and cognitive sciences. Looking at practice as well as theory, the authors explore the impacts that interventions and contextual influences, such as societal change and education reform, have had on efforts to achieve gender parity in SMET. The article concludes with the recommendation of logical next steps to preserve and expand the gains made by women in these fields.

Subject Headings: SMET; Taking stock; Minority women

Keywords: Taking Stock: Where We'Ve Been, Where We Are, Where We'Re Going
  Call Number Serial 2382  
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