An inclusive Research Education Community (iREC) Hanauer, David I.; Graham, Mark J.; SEA-PHAGES ...
Proceedings of the National Academy of Sciences - PNAS,
12/2017, Letnik:
114, Številka:
51
Journal Article
Recenzirano
Odprti dostop
Engaging undergraduate students in scientific research promises substantial benefits, but it is not accessible to all students and is rarely implemented early in college education, when it will have ...the greatest impact. An inclusive Research Education Community (iREC) provides a centralized scientific and administrative infrastructure enabling engagement of large numbers of students at different types of institutions. The Science Education Alliance–Phage Hunters Advancing Genomics and Evolutionary Science (SEA-PHAGES) is an iREC that promotes engagement and continued involvement in science among beginning undergraduate students. The SEA-PHAGES students show strong gains correlated with persistence relative to those in traditional laboratory courses regardless of academic, ethnic, gender, and socioeconomic profiles. This persistent involvement in science is reflected in key measures, including project ownership, scientific community values, science identity, and scientific networking.
ABSTRACT
Discussing the particularly long gravitational microlensing event OGLE-2014-BLG-1186 with a time-scale tE ∼ 300 d, we present a methodology for identifying the nature of localised deviations ...from single-lens point-source light curves, which ensures that (1) the claimed signal is substantially above the noise floor, (2) the inferred properties are robustly determined and their estimation is not subject to confusion with systematic noise in the photometry, (3) alternative viable solutions within the model framework are not missed. Annual parallax and binarity could be separated and robustly measured from the wing and the peak data, respectively. We find matching model light curves that involve either a binary lens or a binary source, and discover hitherto unknown model ambiguities. Our binary-lens models indicate a planet of mass M2 = (45 ± 9) M⊕, orbiting a star of mass M1 = (0.35 ± 0.06) M⊙, located at a distance DL = (1.7 ± 0.3) kpc from Earth, whereas our binary-source models suggest a brown-dwarf lens of M = (0.046 ± 0.007) M⊙, located at a distance DL = (5.7 ± 0.9) kpc, with the source potentially being a (partially) eclipsing binary involving stars predicted to be of similar colour given the ratios between the luminosities and radii. Further observations might resolve the ambiguity in the interpretation in favour of either a lens or a source binary. We experienced that close binary source stars pose a challenge for claiming the detection of planets by microlensing in events where the source passes very close to the lens star hosting the planet.
Synopsis
Materials in contact with liquids on the human skin surface may dissolve and permeate into skin. Release and permeation of chemicals in contact with skin is often estimated in vitro using ...artificial skin liquids, although sebum lipids are generally not included in these models. The purposes of this research were to develop a representative artificial sebum that contains the appropriate types of lipids at levels that match human values and quantitatively characterize the model to understand its utility for in vitro testing. Artificial sebum that consisted of 10 lipids at proportions that closely resembled human sebum was characterized using thin layer chromatography under a variety of storage and use conditions (dry and liquid, 4°C and 32°C, with and without vitamin E) for 28 days. Levels of sebum constituents maintained in solution and dry at 4°C were stable through the duration of the test period. Levels of all sebum lipids maintained dry at 32°C were stable in the presence of vitamin E; however, squalene oxidized rapidly in the absence of vitamin E. Liquids on the human skin surface consist of sebum and sweat with minor amounts of cellular debris and intercellular lipid from the stratum corneum. The relative importance of each component for release of chemicals from materials in contact with skin will depend upon the type of material (metal, organic, etc.). A model artificial sebum was formulated and characterized to aid researchers in understanding potential release of chemicals from materials in contact with skin and subsequent partitioning and absorption.
Résumé
les éléments en contact avec les liquides de surface de la peau humaine peuvent se dissoudre et pénétrer dans la peau. La libération et la pénétration de produits chimiques en contact avec la peau sont souvent évalués in vitro en utilisant des liquides cutanés artificiels, bien que les lipides de sébum ne soient généralement pas inclus dans ces modèles. les buts de ce travail étaient de développer un sébum artificiel représentatif contenant les types de lipides appropriés aux concentrations qui correspondent aux valeurs humaines et de caractériser quantitativement ce modèle pour comprendre son utilité lors de test in vitro. Un sébum artificiel consisté de 10 lipides en proportion proches de celles du sébum humain a été caractérisé en utilisant la chromatographie de couche mince dans divers conditions de conservation et d’utilisation (sec et liquide, 4°C et 32°C, avec et sans vitamine E) pendant 28 jours. les proportions des constituants du sébum maintenu en solution et sécher à 4°C étaient stables durant la durée du test. Ceux du sébum maintenu sec à 32°C étaient stables en présence de vitamine E; cependant, le squalène s’oxydait rapidement en absence de vitamine E. les Liquides de surface de la peau humaine consistent en du sébum, de la sueur avec des quantités mineures de débris cellulaires et des lipides intercellulaires du stratum corneum. L’importance relative de chaque composant pour la libération de molécules à partir de produits en contact avec la peau dépendra du type de produit (métallique, biologique, etc.). Un modèle de sébum artificiel a été formulé et caractérisé pour aider des chercheurs dans la compréhension de la libération de molécules à partir de produits en contact avec la peau et du partage et de l’absorption qui en découle.
•Six tree species: fir, larch, spruce, pine, beech, and ash – were damaged by bears.•Conifers tree species were more frequently damaged than deciduous.•Mean forage ratio was higher for larch than for ...fir, spruce and pine.•The improvement in fir condition and the bear numbers had influence on damage scale.•Tree damage by bears is not a substantial problem for forest management in Poland.
We present a long-term quantitative analysis of forest damage caused by the brown bear (Ursus arctos) in the biggest refuge of this species in Poland. Based on questionnaires distributed to the relevant authorities we estimated the number of trees damaged by bears in 1991–2013, changes in the tree species composition and large-scale factors potentially affecting the extent of damage. We also discuss the importance of bear tree damage to forest management. Throughout the 23years of the study we recorded 6937 trees damaged by bears: a clearly increasing trend and distinct fluctuations in tree numbers and species composition were discernible. Conifers (91.7% – fir 70.0%, larch 11.3%, spruce 9.5%, pine 0.9%) were more frequently damaged than deciduous species (2.9%). Larch and spruce were preferentially affected during the whole study period, and the preference for larch was distinct when collated with its availability in forest stands – a forage ratio of 0.50 compared to 0.35 for fir, 0.17 for spruce and 0.13 for pine. In 2003, however, bears suddenly switched to fir and it is this species that now predominates among the damaged trees, reaching 96.5% in 2013.
Two models based on minimum AICc values were best explaining damage to trees. The most parsimonious model contained one explanatory variable: brown bear population size. The second best model included both bear population size and the average fir tree-ring width. Neither fluctuations in daily temperatures nor the number of days with snow cover had any influence on the scale of damage. Our findings suggest that damage caused by bears is not to be regarded as a serious problem by forest management in Poland and it is unlikely to reach a level of economic significance in the short term.
Individuals with mental disorders are at an elevated risk of developing chronic age-related physical diseases. However, it is not clear whether psychopathology is also associated with processes of ...accelerated aging that precede the onset of age-related disease.
To test the hypothesis that a history of psychopathology is associated with indicators of accelerated aging at midlife.
This prospective cohort study was based on the Dunedin Multidisciplinary Health and Development Study, a population-representative birth cohort of 1037 individuals born between April 1, 1972, and March 31, 1973, in Dunedin, New Zealand. Members were followed up to age 45 years (until April 2019). Data were analyzed from January 6 to December 7, 2020.
Mental disorders were assessed in 6 diagnostic assessments from ages 18 to 45 years and transformed through confirmatory factor analysis into continuous measures of general psychopathology (p-factor) and dimensions of internalizing, externalizing, and thought disorders (all standardized to a mean SD of 100 15).
Signs of aging (biological pace of aging; declines in sensory, motor, and cognitive functioning; and facial age) were assessed up to age 45 years using previously validated measures including biomarkers, clinical tests, and self-reports.
Of the original 1037 cohort participants, 997 were still alive at age 45 years, of whom 938 (94%) were assessed (474 men 50.5%). Participants who had experienced more psychopathology exhibited a faster pace of biological aging (β, 0.27; 95% CI, 0.21-0.33; P < .01); experienced more difficulties with hearing (β, 0.18; 95% CI, 0.12-0.24; P < .01), vision (β, 0.08; 95% CI, 0.01-0.14; P < .05), balance (β, 0.20; 95% CI, 0.14-0.26; P < .01), and motor functioning (β, 0.19; 95% CI, 0.12-0.25; P < .01); experienced more cognitive difficulties (β, 0.24; 95% CI, 0.18-0.31; P < .01); and were rated as looking older (β, 0.20; 95% CI, 0.14-0.26; P < .01). Associations persisted after controlling for sex, childhood health indicators, maltreatment, and socioeconomic status and after taking into account being overweight, smoking, use of antipsychotic medication, and the presence of physical disease. Tests of diagnostic specificity revealed that associations were generalizable across externalizing, internalizing, and thought disorders.
In this cohort study, a history of psychopathology was associated with accelerated aging at midlife, years before the typical onset of age-related diseases. This link is not specific to any particular disorder family but generalizes across disorders. Prevention of psychopathology and monitoring of individuals with mental disorders for signs of accelerated aging may have the potential to reduce health inequalities and extend healthy lives.
Many motion-sensitive tangential cells of the lobula plate in blowflies are well described with respect to their visual response properties and the connectivity among them. They have large and ...complex receptive fields with different preferred directions in different parts of their receptive fields matching the optic flow that occurs during various flight maneuvers. However, much less is known about how tangential cells connect to postsynaptic neurons descending to the motor circuits in the thoracic ganglion and how optic flow is represented in these downstream neurons. Here we describe the physiology and the connectivity of a prominent descending neuron called DNOVS1 (for descending neurons of the ocellar and vertical system). We find that DNOVS1 is electrically coupled to a subset of vertical system cells. The specific wiring leads to a preference of DNOVS1 for rotational flow fields around a particular body axis. In addition, DNOVS1 receives input from interneurons connected to the ocelli.
Effects of computer-provided reading activities on the language performance of 55 adults with chronic aphasia were studied. Results suggest that computerized reading treatment can be administered ...with minimal clinician assistance; improvement on computerized tasks generalized to non-computer language performance; improvement resulted from the language content of software and not from stimulation provided by the computer; and computerized treatment was efficacious. (Author/PB)
The mission of the United States Culture Collection Network (USCCN; http://usccn.org) is "to facilitate the safe and responsible utilization of microbial resources for research, education, industry, ...medicine, and agriculture for the betterment of human kind." Microbial culture collections are a key component of life science research, biotechnology, and emerging global biobased economies. Representatives and users of several microbial culture collections from the United States and Europe gathered at the University of California, Davis, to discuss how collections of microorganisms can better serve users and stakeholders and to showcase existing resources available in public culture collections.
Three-month-old human infants use vocal cues of body size Pietraszewski, David; Wertz, Annie E.; Bryant, Gregory A. ...
Proceedings of the Royal Society. B, Biological sciences,
06/2017, Letnik:
284, Številka:
1856
Journal Article
Recenzirano
Differences in vocal fundamental (Fo) and average formant (Fn) frequencies covary with body size in most terrestrial mammals, such that larger organisms tend to produce lower frequency sounds than ...smaller organisms, both between species and also across different sex and life-stage morphs within species. Here we examined whether three-month-old human infants are sensitive to the relationship between body size and sound frequencies. Using a violation-of-expectation paradigm, we found that infants looked longer at stimuli inconsistent with the relationship—that is, a smaller organism producing lower frequency sounds, and a larger organism producing higher frequency sounds—than at stimuli that were consistent with it. This effect was stronger for fundamental frequency than it was for average formant frequency. These results suggest that by three months of age, human infants are already sensitive to the biologically relevant covariation between vocalization frequencies and visual cues to body size. This ability may be a consequence of developmental adaptations for building a phenotype capable of identifying and representing an organism's size, sex and life-stage.
PDF
