Effect of continuous gamma-ray exposure on performance of learned tasks and effect of subsequent fractionated exposures on blood-forming tissue

Sixteen monkeys trained to perform continuous and discrete-avoidance and fixed-ratio tasks with visual and auditory cues were performance-tested before, during, and after 10-day gamma-ray exposures totaling 0, 500, 750, and 1000 rads. Approximately 14 months after the performance-test exposures, surviving animals were exposed to 100-rad gamma-ray fractions at 56-day intervals to observe injury and recovery patterns of blood-forming tissues. The fixed-ratio, food-reward task performance showed a transient decline in all dose groups within 24 hours of the start of gamma-ray exposure, followed by recovery to normal food-consumption levels within 48 to 72 hours. Avoidance tasks were performed successfully by all groups during the 10-day exposure, but reaction times of the two higher dose-rate groups in which animals received 3 and 4 rads per hour or total doses of 750 and 1000 rads, respectively, were somewhat slower

Bar coding MS2 spectra for metabolite identification

[Image: see text] Metabolite identifications are most frequently achieved in untargeted metabolomics by matching precursor mass and full, high-resolution MS(2) spectra to metabolite databases and standards. Here we considered an alternative approach for establishing metabolite identifications that does not rely on full, high-resolution MS(2) spectra. First, we select mass-to-charge regions containing the most informative metabolite fragments and designate them as bins. We then translate each metabolite fragmentation pattern into a binary code by assigning 1’s to bins containing fragments and 0’s to bins without fragments. With 20 bins, this binary-code system is capable of distinguishing 96% of the compounds in the METLIN MS(2) library. A major advantage of the approach is that it extends untargeted metabolomics to low-resolution triple quadrupole (QqQ) instruments, which are typically less expensive and more robust than other types of mass spectrometers. We demonstrate a method of acquiring MS(2) data in which the third quadrupole of a QqQ instrument cycles over 20 wide isolation windows (coinciding with the location and width of our bins) for each precursor mass selected by the first quadrupole. Operating the QqQ instrument in this mode yields diagnostic bar codes for each precursor mass that can be matched to the bar codes of metabolite standards. Furthermore, our data suggest that using low-resolution bar codes enables QqQ instruments to make MS(2)-based identifications in untargeted metabolomics with a specificity and sensitivity that is competitive to high-resolution time-of-flight technologies

Numerical simulation of the upward propagation of a flame in a vertical tube filled with a very lean mixture.

Upwardpropagation of a premixed flame in averticaltubefilled with a very leanmixture is simulated numerically using a single irreversible Arrhenius reaction model with infinitely high activation energy. In the absence of heat losses and preferential diffusion effects, a curved flame with stationary shape and velocity close to those of an open bubble ascending in the same tube is found for values of the fuel mass fraction above a certain minimum that increases with the radius of the tube, while the numerical computations cease to converge to a stationary solution below this minimum mass fraction. The vortical flow of the gas behind the flame and in its transport region is described for tubes of different radii. It is argued that this flow may become unstable when the fuel mass fraction is decreased, and that this instability, together with the flame stretch due to the strong curvature of the flame tip in narrow tubes, may be responsible for the minimum fuel mass fraction. Radiation losses and a Lewis number of the fuel slightly above unity decrease the final combustion temperature at the flame tip and increase the minimum fuel mass fraction, while a Lewis number slightly below unity has the opposite effect

Comparison and Mapping Facilitate Relation Discovery and Predication

Relational concepts play a central role in human perception and cognition, but little is known about how they are acquired. For example, how do we come to understand that physical force is a higher-order multiplicative relation between mass and acceleration, or that two circles are the same-shape in the same way that two squares are? A recent model of relational learning, DORA (Discovery of Relations by Analogy; Doumas, Hummel & Sandhofer, 2008), predicts that comparison and analogical mapping play a central role in the discovery and predication of novel higher-order relations. We report two experiments testing and confirming this prediction

Teores de óleo e proteína em grãos de soja, com diferentes manejos de percevejo, da colheita ao armazenamento, utilizando a espectroscopia no infravermelho próximo (NIR).

ABSTRACT: The aim was to determine changes in oil and protein content in soybean grain after different stink bugs field managements, on harvest and after of grain storage, using near infrared spectroscopy (NIR). Three stink bugs control managements were used in the soybean crop season as: 1-soybean producer management area; 2-standard integrated pest management area; 3-control management area (no pesticides applied). After harvest and at 3, 6, 9 and 12 months after storage time, samples of grain were taken to analyze oil and protein content at NIR. The experiment was maintained in a room at 25° C and 60% of relative humidity during one year of storage time. The results showed an increase in protein and a decrease in lipid content during storage. The increase of stink bug attack in the field caused an increase in the protein content during storage, however no changes in lipid content occurred. RESUMO: O objetivo do trabalho foi verificar variação nos teores de óleo e proteína em grãos de soja, com diferentes manejos de percevejo, no momento da colheita e após determinado período de armazenamento, utilizando o NIR. Os tratamentos pesquisados neste estudo foram amostras de grãos de várias lavouras de soja e três condições de tratamentos: 1-área do produtor, 2-área com o MIP e 3-área testemunha. O experimento foi conduzido em BODs, sendo as avaliações no ponto zero (colheita), aos três, seis, nove e doze meses de armazenamento. Em condições ideais de armazenamento (25ºC e umidade relativa de 60%), ocorreu um aumento nos teores de proteína e uma diminuição nos teores de lipídios dos grãos de soja ao longo do armazenamento. O aumento de ataque de percevejos ocasionou aumento nos teores de proteína dos grãos de soja durante o armazenamento, entretanto sem alterar os teores de lipídios dos grãos

Accreting Protoplanets in the LkCa 15 Transition Disk

Exoplanet detections have revolutionized astronomy, offering new insights into solar system architecture and planet demographics. While nearly 1900 exoplanets have now been discovered and confirmed, none are still in the process of formation. Transition discs, protoplanetary disks with inner clearings best explained by the influence of accreting planets, are natural laboratories for the study of planet formation. Some transition discs show evidence for the presence of young planets in the form of disc asymmetries or infrared sources detected within their clearings, as in the case of LkCa 15. Attempts to observe directly signatures of accretion onto protoplanets have hitherto proven unsuccessful. Here we report adaptive optics observations of LkCa 15 that probe within the disc clearing. With accurate source positions over multiple epochs spanning 2009 - 2015, we infer the presence of multiple companions on Keplerian orbits. We directly detect H{\alpha} emission from the innermost companion, LkCa 15 b, evincing hot (~10,000 K) gas falling deep into the potential well of an accreting protoplanet.Comment: 35 pages, 3 figures, 1 table, 9 extended data item

The HOSTS Survey for Exozodiacal Dust: Preliminary results and future prospects

[abridged] The presence of large amounts of dust in the habitable zones of nearby stars is a significant obstacle for future exo-Earth imaging missions. We executed an N band nulling interferometric survey to determine the typical amount of such exozodiacal dust around a sample of nearby main sequence stars. The majority of our data have been analyzed and we present here an update of our ongoing work. We find seven new N band excesses in addition to the high confidence confirmation of three that were previously known. We find the first detections around Sun-like stars and around stars without previously known circumstellar dust. Our overall detection rate is 23%. The inferred occurrence rate is comparable for early type and Sun-like stars, but decreases from 71% [+11%/-20%] for stars with previously detected mid- to far-infrared excess to 11% [+9%/-4%] for stars without such excess, confirming earlier results at high confidence. For completed observations on individual stars, our sensitivity is five to ten times better than previous results. Assuming a lognormal luminosity function of the dust, we find upper limits on the median dust level around all stars without previously known mid to far infrared excess of 11.5 zodis at 95% confidence level. The corresponding upper limit for Sun-like stars is 16 zodis. An LBTI vetted target list of Sun-like stars for exo-Earth imaging would have a corresponding limit of 7.5 zodis. We provide important new insights into the occurrence rate and typical levels of habitable zone dust around main sequence stars. Exploiting the full range of capabilities of the LBTI provides a critical opportunity for the detailed characterization of a sample of exozodiacal dust disks to understand the origin, distribution, and properties of the dust.Comment: To appear in SPIE Astronomical Telescopes + Instrumentation 2018 proceedings. Some typos fixed, one reference adde

FAN RESPONSE TO LEAGUE PLAYOFF STRUCTURE AND CONSECUTIVE SEASON COMPETITIVE BALANCE IN PROFESSIONAL SPORTS

Competitive balance (the level of equality of playing talent across teams) is presumed to be a necessary element for league success due to the unique inter-dependent economic nature of professional sports which requires teams to have financially healthy rivals in order to field games (Rottenberg 1956). Underlying this notion is the uncertainty of outcome hypothesis, which suggests that a fan’s interest in professional sports is dependent on various levels of uncertainty of outcome: individual game uncertainty (who will win the game), individual season uncertainty (who will win the championship), and consecutive season uncertainty (does the same team win the championship every year) (Cairns 1987). Although there is an expanding body of literature that empirically tests the uncertainty of outcome hypothesis, most of it focuses on attendance responses to within-game or within-season measures of competitive balance. In addition, nearly all previous studies focus on regular season outcomes only and completely ignore the playoffs (Longley and Lacey 2012). Filling in a notable gap in the literature, this dissertation thus uses a new metric of competitive balance that relies on inter-seasonal measures of qualification for and advancement in the playoffs. In addition to measuring fan response to this new measure of competitive balance that incorporates both playoff outcomes and consecutive season effects in a novel way, this dissertation also investigates the effects of league playoff rules on competitive balance. No previous study has analyzed how the number of teams that qualify for the playoffs affects fan interest in a league through competitive balance concerns. On the one hand, increasing the number of teams that qualify for the playoffs should increase fan interest by increasing the overall pool of teams that are competitive for a playoff spot. On the other hand, increasing the number of teams that qualify for the playoffs shifts the importance from the regular season to the playoffs, reducing fan interest in the regular season. This dissertation empirically investigates the issue of fan response (as measured by league-wide regular season attendance figures) to varying levels of inter-seasonal competitive balance as measured by the churn of playoff qualifying/advancing teams and as affected by league playoff structures that dictate the number of teams making the playoffs. The results show that small changes in league playoff structure can significantly affect attendance. It is predicted that if Major League Baseball were to further increase the number of teams that make the playoffs from 10 to 12, the average attendance per game would increase by over 4,300 (about 14% of the current average). In the National Hockey League, a reduction in the number of teams that make the playoffs from 16 to 14 is expected to increase the average attendance per game by over 700 (about 4% of the current average). These results highlight the importance of including playoff considerations when investigating the uncertainty of outcome hypothesis as well as the value of competitive balance to sport league success

Effects of shore-parallel structures on meiofauna In the intertidal foreshore of a sandy estuarine beach, Raritan Bay, New Jersey, USA

Field investigations conducted at three sites on the intertidal sandy foreshore at Cliffwood Beach and Keyport Harbor, Raritan Bay, New Jersey reveal the relationship between meiofaunal density, wave and beach characteristics at sites where bulkheads and seawalls are present and at an adjacent site where they are not. Wave characteristics were gathered at 2 hz over the tidal cycle with a pressure transducer. Three replicate core samples, to a depth of 0. 10 m, were gathered at four sampling stations across the foreshore at low tide to determine meiofaunal density. A fourth core sample was used to determine grain size, sorting and moisture content. Net change, depth of sediment activation, and beach elevation were measured at low tide. At Cliffwood Beach, significant wave heights were 0.05-0.13 m with periods of 5.9 - 7.7 s. Meiofaunal. densities ranged from I - 309 ind./10cm2. Sediments are finer (0.29 mm) and better sorted (0.54 Φ) immediately fronting the seawall resulting in lower meiofaunal densities. One-way analysis of variance revealed differences between meiofaunal densities, within the bottom 0.07 m of the core, immediately fronting the seawall and at a similar elevation at the control site. At Keyport Harbor, significant wave heights were 0.08-0.27 m with periods of 2.0 s. Meiofaunal densities ranged from 2-207 ind./10 cm2. Sediments are finer (0.4 mm.) and better sorted (0.47 Φ) immediately fronting the bulkheads. One-way analysis of variance revealed differences between meiofaunal densities, within the top 0.03 m of the core, immediately fronting the bulkheads and at a similar elevation at the control site. Depth of activation was 0.23 m at sampling station immediately fronting the bulkhead. Shore-parallel structures have greatest influence when wave energies are high or when the structure is located bayward of wave breaking at high water

Modelling semantic transparency

We present models of semantic transparency in which the perceived trans- parency of English noun–noun compounds, and of their constituent words, is pre- dicted on the basis of the expectedness of their semantic structure. We show that such compounds are perceived as more transparent when the first noun is more frequent, hence more expected, in the language generally; when the compound semantic rela- tion is more frequent, hence more expected, in association with the first noun; and when the second noun is more productive, hence more expected, as the second ele- ment of a noun–noun compound. Taken together, our models of compound and con- stituent transparency lead us to two conclusions. Firstly, although compound trans- parency is a function of the transparencies of the constituents, the two constituents differ in the nature of their contribution. Secondly, since all the significant predictors in our models of compound transparency are also known predictors of processing speed, perceived transparency may itself be a reflex of ease of processing