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In this invited talk, we discuss the physics of the lifecycle of dust in the context of galaxy formation simulations. After outlining the basic physical processes, we apply algorithms for the formation, growth, and destruction of dust in the ISM to a state-of-the-art cosmological simulation to develop a model for the evolution of the dust to gas and dust to metals ratios in galaxies. We show that while modern simulations are able to match the observed dust mass function at redshift z = 0, most models underpredict the observed mass function at high-redshift (z = 2). We then show the power of these techniques by expanding our model to include a spectrum of dust sizes, and make initial predictions for extinction laws in local galaxies.
Galaxies are complicated physical systems which obey complex scaling relationships; as a result, properties measured from broadband photometry are often highly correlated, degenerate, or both. Therefore, the accuracy of basic properties like stellar masses and star formation rates (SFRs) depend on the accuracy of many second-order galaxy properties, including star formation histories (SFHs), stellar metallicities, dust properties, and many others. Here, we re-assess measurements of galaxy stellar masses and SFRs using a 14-parameter physical model built in the Prospector Bayesian inference framework. We find that galaxies are ∼0.2 dex more massive and have ∼0.2 dex lower star formation rates than classic measurements. These measurements lower the observed cosmic star formation rate density and increase the observed buildup of stellar mass, finally bringing these two metrics into agreement at the factor-of-two level at 0.5 < z < 2.5.
OBJECTIVES/SPECIFIC AIMS: To translate a behavioral theory–informed, evidence-based, face-to-face health education program into an mHealth lifestyle intervention for African-Americans (AAs). METHODS/STUDY POPULATION: This mixed methods study consisted of 4 phases, using an iterative development process to intervention design with the AA community. In Phase 1, we held focus groups with AA community members and church partners (n=23) to gain insight regarding the needs and preferences of potential app end users. In Phase 2, the interdisciplinary research team synthesized input from Phase 1 for preliminary app design and content development. Phase 3 consisted of a sequential 3-meeting series with the church partners (n=13) for iterative app prototyping (assessment, cultural tailoring, final review). Phase 4 was a single group pilot study among AA church congregants (n=50) to assess app acceptability, usability, and satisfaction. RESULTS/ANTICIPATED RESULTS: Phase 1 focus groups indicated preferences for general and health related apps: multifunctional; high-quality graphics/visuals; evidence-based, yet simple health information; and social networking capability. Phase 2 integrated these preferences into the preliminary app prototype. Feedback from Phase 3 was used to refine the FAITH! App prototype for pilot testing. Phase 4 pilot testing indicated high acceptability, usability, and satisfaction of the FAITH! App. DISCUSSION/SIGNIFICANCE OF IMPACT: This study illustrates the process of using formative and CBPR approaches to design a culturally relevant, mHealth lifestyle intervention to address CV health disparities within the AA community. Given the positive perceptions of the app, our study supports the use of an iterative development process by others interested in implementing an mHealth lifestyle intervention for racial/ethnic minority communities.
α-Tocopherol is the principal source of vitamin E, an essential nutrient that plays a crucial role in maintaining healthy brain function. Infant formula is routinely supplemented with synthetic α-tocopherol, a racaemic mixture of eight stereoisomers with less bioactivity than the natural stereoisomer RRR-α-tocopherol. α-Tocopherol stereoisomer profiles have not been previously reported in the human brain. In the present study, we analysed total α-tocopherol and α-tocopherol stereoisomers in the frontal cortex (FC), hippocampus (HPC) and visual cortex (VC) of infants (n 36) who died of sudden infant death syndrome or other conditions. RRR-α-tocopherol was the predominant stereoisomer in all brain regions (P<0·0001) and samples, despite a large intra-decedent range in total α-tocopherol (5–17 μg/g). Mean RRR-α-tocopherol concentrations in FC, HPC and VC were 10·5, 6·8 and 5·5 μg/g, respectively. In contrast, mean levels of the synthetic stereoisomers were RRS, 1–1·5; RSR, 0·8–1·0; RSS, 0·7–0·9; and Σ2S 0·2–0·3 μg/g. Samples from all but two decedents contained measurable levels of the synthetic stereoisomers, but the intra-decedent variation was large. The ratio of RRR:the sum of the synthetic 2R stereoisomers (RRS+RSR+RSS) averaged 2·5, 2·3 and 2·4 in FC, HPC and VC, respectively, and ranged from 1 to at least 4·7, indicating that infant brain discriminates against synthetic 2R stereoisomers in favour of RRR. These findings reveal that RRR-α-tocopherol is the predominant stereoisomer in infant brain. These data also indicate that the infant brain discriminates against the synthetic 2R stereoisomers, but is unable to do so completely. On the basis of these findings, investigation into the impact of α-tocopherol stereoisomers on neurodevelopment is warranted.
I'm a choreographer and I make performance installation. I am from a very small town on the Kenai Peninsula of Alaska. I'm Yup'ik on my father's side, and my Alaska family is from the Yukon-Kuskokwim Delta. I share this because it's where I'm from, and it's also where my work is from: the physical place of Alaska, and the confluence of my heritage and performance work.
The goal of this study was to examine whether growth delay can serve as an index of allostatic load during early development, as it is well known that the activity of stress-mediating systems inhibits growth. The participants were children adopted internationally from institutional care (n = 36), children adopted internationally from foster care (n = 26), and nonadopted children (n = 35). For the adopted children, height for age and weight for height were assessed at adoption; for all children, disinhibited social approach (DSA; termed elsewhere as “indiscriminate friendliness”) and diurnal cortisol were assessed at 6–8 years (M = 6.9 years). For internationally adopted children in general, and postinstitutionalized children specifically, linear growth delay assessed at the time of adoption was associated with more dysregulated behavior in response to an unfamiliar adult (i.e., greater DSA) and a more dysregulated diurnal cortisol rhythm (i.e., higher late afternoon and evening values). Further, among the most growth-delayed children, higher cortisol levels later in the day were correlated with DSA. The potential for using growth delay as an allostatic load indicator and the possible problems and limitations in its use in child populations are discussed.
The spatial configuration of minorities relative to Whites in a metropolitan area, or residential segregation, has been identified as a significant barrier to access to employment opportunities for racial/ethnic minorities, including Latinos, in metropolitan labor markets. Dominating the research are tests of place stratification models that focus on segregated ethnic enclaves or the mismatch between minority communities and employment opportunities. Both approaches focus on predominantly Latino neighborhoods and communities, but overlook their structural location and isolation in the broader metropolitan labor market. This study examines whether and to what extent structural characteristics of metropolitan labor markets in which Mexicans, Puerto Ricans, and Cubans live and work shape their employment opportunities and whether or not these relationships vary across the three Latino native-origin groups. We utilize a unique dataset of the demographic, employment, educational, occupational, and industrial characteristics of the 95 largest US cities. The analyses feature both OLS regression to ascertain if varying levels of segregation across metropolitan areas in 2000 is associated with different levels of employment for Latinos, and a fixed-effects analysis to determine if changes in these structural factors between 1980 and 2000 within the same labor market affect the employment rates of Latinos in that metropolitan area. We find that segregation has a deleterious effect on Latino men's employment; in cities where segregation is worse, their employment rates are lower, and as the cities that they live in became more segregated over the 20 year period of study, their employment rates decreased.
The influence of adding InF3 as a reducing agent on the oxidation state of Eu in fluoro-chloro- (FCZ) and fluorobromozirconate (FBZ) glass ceramics was investigated using x-ray ab-sorption near edge (XANES) and photoluminescence (PL) spectroscopy. For both materials, it was found that InF3 decreases the Eu2+-to-Eu3+ ratio significantly. PL spectroscopy proved that an annealing step leads to the formation of Eu-doped BaCl2 and BaBr2 nanocrystals in the FCZ and FBZ glasses, respectively. In the case of FCZ glass ceramics the hexagonal phase of BaCl2 could be detected in indium-free and InF3-doped ceramics, but only for InF3 containing FCZ glass ceramics a phase transition of the nanoparticles from hexagonal to orthorhombic structure is observed. For the FBZ glass ceramics, the hexagonal phase of BaBr2 can be formed with and without indium doping, but only in the indium-free case a phase transition to orthorhombic BaBr2 could be found.
Carbon-based coatings exhibit many attractive properties that make them good candidates for a wide range of engineering applications. Tribological studies of the films have revealed a close correlation between the chemistry of the hydrocarbon source gases and the coefficients of friction and wear rates of the diamond-like carbon films. Those films grown in source gases with higher hydrogen-to-carbon ratios had much lower coefficients of friction and wear rates than did films derived from source gases with lower hydrogen-to-carbon ratios. The mechanism for this low friction is as yet not properly understood. Ongoing structural characterization of the films at Argonne National Laboratory is gradually revealing this mechanism. Recent studies have included x-ray photoelectron spectroscopy (XPS), near edge x-ray absorption fine structure (NEXAFS) and x-ray reflectivity (XRR). XPS showed ∼10% oxygen at the surface, which was largely removed after a 1 minute sputter; NEXAFS showed a high sp2:sp3 ratio implying a highly graphitic material; and XRR has given a comprehensive depth profile, with three layers of increasing density as the substrate was approached. The paper discusses the results and correlation with previous friction measurements.
The incidence of food refusal associated with illness is reviewed, not
illness by illness, but according to those factors that affect the ability to eat;
normal learning about eating, aversive learning about eating, regulation of
appetite, children's cognitions about foods, and parental anxiety about
intake. Diseases affecting the major organs are likely to generate food
refusal based on at least one of these factors, if not all of them. However,
some minor disease processes can also have a major impact on food
acceptance. Child temperament also affects food acceptance and may
interact with the disease process to produce food refusal.
ABSTRACT. A series of studies examines whether certain biases in probability assessments and perceptions of loss, previously found in experimental studies, affect consumers' decisions about insurance. Framing manipulations lead the consumers studied here to make hypothetical insurance-purchase choices that violate basic laws of probability and value. Subjects exhibit distortions in their perception of risk and framing effects in evaluating premiums and benefits. Illustrations from insurance markets suggest that the same effects occur when consumers make actual insurance purchases.
KEY WORDS insurance decisions, biases, probability distortions, framing
Insurance purchases form the basis for an extraordinarily large industry. The industry has assets of $1.6 trillion and employs over 2 million people (Insurance Information Institute, 1990a). Consumers are responsible for a significant proportion of this market, either directly through their own purchase decisions, or indirectly through their choices of employers, mortgages, etc. These investments are sizable and commonplace. For example, the average insured household carries over $100,000 of life insurance, and surveys reveal that 70% of all households report having property insurance. Insurance represents, perhaps, the most significant tool for managing financial risks available to individuals.
The last decade has seen the advent of an “insurance crisis” in the U.S. and several other countries. With respect to liability insurance, for example, there have been large increases in premiums and vanishing coverage for some risks, factors that present major problems for businesses, professionals, and consumers (Committee for Economic Development, 1989).
The present paper reports on the phonological form of one child's
productive vocabulary from age 0;10 to 1;8 with primary focus on his
production of multisyllabic targets. A large percentage of his multisyllabic
vocabulary was produced as one syllable until the age of 1;6.
This limitation was not due to a tendency to extract only single syllables
from the speech stream, but rather due primarily to a limitation on
production. While some portion of his one-syllable productions could be
interpreted as the result of single syllable extraction, a sizeable portion
affirmed that he extracted the target size correctly by his inclusion of first
and final target phonemes in his productions (e.g. [po] for piano and
[kiz] for candies). The resolution of this limitation coincides with his
move toward two-word speech. We conclude that there is a developmental and
perhaps maturational limitation in the capacity to carry
out the processes underlying word and sentence production.
The present study evaluates the role of age on the rate of acquiring English as a second language in an immersion setting. Subjects were children with native languages typologically very different from English. The children arrived in the United States between the ages of 7 and 12 years and were tested on their knowledge of English grammatical morphology and syntax at different lengths of stay in the United States, ranging from 6 months to 3 years. Subjects' performance was predicted by the length of their stay in the United States and by gender, with females outperforming males. Age of arrival played no role in predicting subjects' rate of acquisition. Performance was very similar between two age groups examined (7–9– and 10–12-year-old arrivals) throughout the 3 years measured. The present results suggest that, on certain aspects of grammar, different-aged children acquire a second language during the first 3 years of acquisition at similar rates when their native language is very different in typology from the target language.
The objective of this work is to identify synthetic pathways for materials useful in the effective repair of the skeletal system. Ideally a universal artificial bone would be identified that can function as a cementitious, pseudoplastic, or structural material. The cementitious form would be very important for bone adhesives that repair bone fractures and restore bone defects. The pseudoplastic form would aid in the in situ reconstruction of anatomical defects and the structural material could be used to prefabricate prostheses. It is critical of course for all these forms of the artificial bone to have strongly regenerative properties so that as implants they would integrate microscopically with natural bone.
Two hearing children of deaf parents (initially 3;9 and 1;8) had been cared for almost exclusively by their mother, who did not speak or sign to them. Though the older child had heard language from TV and briefly at nursery school, his speech was below age level and structurally idiosyncratic. Intervention led to improvement in his expressive abilities, and by 4;2 the deviant utterance patterns had disappeared. In later years, his spontaneous speech and school performance were normal, though language testing revealed some weak areas. The younger child initially used no speech, but acquired language normally after intervention, with his brother as model. Implications for understanding the role of linguistic input in language development are discussed.
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