473 research outputs found

    Confirmed presence of the squash bee, Peponapis pruinosa (Say, 1837) in the state of Oregon and specimen-based observational records of Peponapis (Say, 1837) (Hymenoptera: Anthophila) in the Oregon State Arthropod Collection

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    A new Oregon record for Peponapis pruinosa (Say, 1837) is presented with notes on its occurrence and photographs. This record provides the first empirical evidence of the genus and species in the state of Oregon. A dataset of Peponapis (Say, 1837) specimens in the holdings of the Oregon State Arthropod Collection is included with a brief summary of its contents

    Spin-parities of sub-threshold resonances in the 18^{18}F(p, α\alpha)15^{15}O reaction

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    The 18^{18}F(p, α\alpha)15^{15}O reaction is key to determining the 18^{18}F abundance in classical novae. However, the cross section for this reaction has large uncertainties at low energies largely caused by interference effects. Here, we resolve a longstanding issue with unknown spin-parities of sub-threshold states in 19^{19}Ne that reduces these uncertainties. The 20^{20}Ne(3^3He, 4^4He)19^{19}Ne neutron pick-up reaction was used to populate 19^{19}Ne excited states, focusing on the energy region of astrophysical interest (≈\approx 6 - 7 MeV). The experiment was performed at the Triangle Universities Nuclear Laboratory using the high resolution Enge split-pole magnetic spectrograph. Spins and parities were found for states in the astrophysical energy range. In particular, the state at 6.133 MeV (Erc.m.=−278_{r}^{\text{c.m.}} = -278 keV) was found to have spin and parity of 3/2+3/2^+ and we confirm the existence of an unresolved doublet close to 6.288 MeV (Erc.m.=−120_{r}^{\text{c.m.}} = -120 keV) with Jπ^{\pi} = 1/2+1/2^+ and a high-spin state. Using these results, we demonstrate a significant factor of two decrease in the reaction rate uncertainties at nova temperatures.Comment: 15 pages, 6 figures, accepted in Phys. Rev. C. Corrected typos and reference

    Spin-parities of sub-threshold resonances in the 18^{18}F(p, αα)15^{15}O reaction

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    The 18^{18}F(p, α\alpha)15^{15}O reaction is key to determining the 18^{18}F abundance in classical novae. However, the cross section for this reaction has large uncertainties at low energies largely caused by interference effects. Here, we resolve a longstanding issue with unknown spin-parities of sub-threshold states in 19^{19}Ne that reduces these uncertainties. The 20^{20}Ne(3^3He, 4^4He)19^{19}Ne neutron pick-up reaction was used to populate 19^{19}Ne excited states, focusing on the energy region of astrophysical interest (≈\approx 6 - 7 MeV). The experiment was performed at the Triangle Universities Nuclear Laboratory using the high resolution Enge split-pole magnetic spectrograph. Spins and parities were found for states in the astrophysical energy range. In particular, the state at 6.133 MeV (Erc.m.=−278_{r}^{\text{c.m.}} = -278 keV) was found to have spin and parity of 3/2+3/2^+ and we confirm the existence of an unresolved doublet close to 6.288 MeV (Erc.m.=−120_{r}^{\text{c.m.}} = -120 keV) with Jπ^{\pi} = 1/2+1/2^+ and a high-spin state. Using these results, we demonstrate a significant factor of two decrease in the reaction rate uncertainties at nova temperatures

    Infrared Excess Sources: Compton Thick QSOs, low luminosity Seyferts or starbursts?

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    We explore the nature of Infrared Excess sources (IRX), which are proposed as candidates for luminous L_X(2-10keV)>1e43erg/s Compton Thick (N_H>2e24cm^{-2})QSOsatz 2.Lowerredshift,z 1,analoguesofthedistantIRXpopulationareidentifiedbyfirstlyredshiftingtoz=2theSEDsofallsourceswithsecurespectroscopicredshiftsintheAEGIS(6488)andtheGOODS−North(1784)surveysandthenselectingthosethatqualifyasIRXsourcesatthatredshift.Atotalof19galaxiesareselected.Themeanredshiftofthesampleis) QSOs at z~2. Lower redshift, z~1, analogues of the distant IRX population are identified by firstly redshifting to z=2 the SEDs of all sources with secure spectroscopic redshifts in the AEGIS (6488) and the GOODS-North (1784) surveys and then selecting those that qualify as IRX sources at that redshift. A total of 19 galaxies are selected. The mean redshift of the sample is z\approx1.WedonotfindstrongevidenceforComptonThickQSOsinthesample.For9sourceswithX−raycounterparts,theX−rayspectraareconsistentwithComptonThinAGN.Only3ofthemshowtentativeevidenceforComptonThickobscuration.TheSEDsoftheX−rayundetectedpopulationareconsistentwithstarburstactivity.Thereisnoevidenceforahotdustcomponentatthemid−infraredassociatedwithAGNheateddust.IftheX−rayundetectedsourceshostAGN,anupperlimitofLX(2−10keV)=1e43erg/sisestimatedfortheirintrinsicluminosity.Weproposethatalargefractionofthe. We do not find strong evidence for Compton Thick QSOs in the sample. For 9 sources with X-ray counterparts, the X-ray spectra are consistent with Compton Thin AGN. Only 3 of them show tentative evidence for Compton Thick obscuration. The SEDs of the X-ray undetected population are consistent with starburst activity. There is no evidence for a hot dust component at the mid-infrared associated with AGN heated dust. If the X-ray undetected sources host AGN, an upper limit of L_X(2-10keV) =1e43erg/s is estimated for their intrinsic luminosity. We propose that a large fraction of the z\approx2$ IRX population are not Compton Thick QSOs but low luminosity [L_X(2-10keV)<1e43erg/s], possibly Compton Thin, AGN or dusty starbursts. It is shown that the decomposition of the AGN and starburst contribution to the mid-IR is essential for interpreting the nature of this population, as star-formation may dominate this wavelength regime.Comment: Accepted by MNRA

    Modular and cultural factors in biological understanding: an experimental approach to the cognitive basis of science

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    What follows is a discussion of three sets of experimental results that deal with various aspects of universal biological understanding among American and Maya children and adults. The first set of experiments shows that by the age of four-to-five years (the earliest age tested in this regard) urban American and Yukatek Maya children employ a concept of innate species potential, or underlying essence, as an inferential framework for understanding the affiliation of an organism to a biological species, and for projecting known and unknown biological properties to organisms in the face of uncertainty. The second set of experiments shows that the youngest Maya children do not have an anthropocentric understanding of the biological world. Children do not initially need to reason about non-human living kinds by analogy to human kinds. The third set of results show that the same taxonomic rank is cognitively preferred for biological induction in two diverse populations: people raised in the Mid-western USA and Itza' Maya of the Lowland Meso-american rainforest. This is the generic species the level of oak and robin. These findings cannot be explained by domain-general models of similarity because such models cannot account for why both cultures prefer species-like groups in making inferences about the biological world, although Americans have relatively little actual knowledge or experience at this level. The implication from these experiments is that folk biology may well represent an evolutionary design: universal taxonomic structures, centred on essence-based generic species, are arguably routine products of our ‘habits of mind,' which may be in part naturally selected to grasp relevant and recurrent ‘habits of the world.' The science of biology is built upon these domain-specific cognitive universals: folk biology sets initial cognitive constraints on the development of any possible macro-biological theory, including the initial development of evolutionary theory. Nevertheless, the conditions of relevance under which science operates diverge from those pertinent to folk biology. For natural science, the motivating idea is to understand nature as it is ‘in itself,' independently of the human observer (as far as possible). From this standpoint, the species-concept, like taxonomy and teleology, may arguably be allowed to survive in science as a regulative principle that enables the mind to readily establish stable contact with the surrounding environment, rather than as an epistemic concept that guides the search for truth

    Ne 21 energy levels approaching the α -particle threshold

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    Background: Nuclei around Ne20 exhibit an interplay of different excitations caused by different aspects of nuclear structure, including single-particle and multiparticle configurations and collective rotations. One-nucleon transfer reactions selectively probe single-particle structures in these nuclei. These nuclei are also important to astrophysics, with a number of important reactions proceeding through this mass region. Purpose: Energy levels approaching the α-particle threshold in Ne21 are of importance to nuclear structure. The Ne20(d,p)Ne21 reaction was measured and the corresponding spectroscopic nuclear information was extracted. Method: States in Ne21 were populated using the Ne20(d,p)Ne21 reaction in forward kinematics. Protons were identified in the Triangle Universities Nuclear Laboratory (TUNL) Enge split-pole spectrograph and angular distributions were extracted. Spin-party assignments were made and neutron partial widths were determined based on distorted-wave Born approximation (DWBA) analysis. Results: Several new energy levels were observed at energies of 7176, 7235, 7250, and 7337 keV, and spin-parities are reported which generally agree with previous results where literature was available. Spin and parity assignments are reported for several energy levels along with estimated neutron widths for those states above the neutron threshold (Sn=6761keV). Conclusions: Results from this study are placed in context with a review of the available literature on all known states in this energy region of Ne21

    Research Recommendations Following the Discovery of Pain Sensitizing IgG Autoantibodies in Fibromyalgia Syndrome

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    BACKGROUND: Fibromyalgia syndrome (FMS) is the most common chronic widespread pain condition in rheumatology. Until recently, no clear pathophysiological mechanism for fibromyalgia had been established, resulting in management challenges. Recent research has indicated that serum IgGs may play a role in FMS. We undertook a research prioritisation exercise to identify the most pertinent research approaches that may lead to clinically implementable outputs. METHODS: Research priority setting was conducted in five phases: situation analysis; design; expert group consultation; interim recommendations; consultation and revision. A dialogue model was used, and an international multi-stakeholder expert group was invited. Clinical, patient, industry, funder, and scientific expertise was represented throughout. Recommendation-consensus was determined via a voluntary closed eSurvey. Reporting guideline for priority setting of health research were employed to support implementation and maximise impact. RESULTS: Arising from the expert group consultation (n = 29 participants), 39 interim recommendations were defined. A response rate of 81.5% was achieved in the consensus survey. Six recommendations were identified as high priority- and 15 as medium level priority. The recommendations range from aspects of fibromyalgia features that should be considered in future autoantibody research, to specific immunological investigations, suggestions for trial design in FMS, and therapeutic interventions that should be assessed in trials. CONCLUSIONS: By applying the principles of strategic priority setting we directed research towards that which is implementable, thereby expediating the benefit to the FMS patient population. These recommendations are intended for patients, international professionals and grant-giving bodies concerned with research into causes and management of patients with fibromyalgia syndrome

    Building brand reputation through third party endorsement : Fair Trade in British Chocolate

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    This article looks at the evolution of the British chocolate industry from the 1860s to the 1960s, a period during which it was dominated by Quaker businesses: Cadbury, Rowntree, and their predecessor, Fry. It provides evidence of early forms of fair trade by these Quaker businesses, showing that, before the fair trade movement took off in the 1970s, they contributed to social change and to improvement in living standards and long-term sustainable economic growth in developing countries. This article argues that when the mechanisms for enforcing food standards were weak and certification bodies did not exist, the Religious Society of Friends acted as an indirect independent endorser, reinforcing the imagery and reputation of the Quaker-owned brands and associating them both with purity and quality and with honest and fair trading

    Tracing the cosmic growth of supermassive black holes to z~3 with Herschel

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    We study a sample of Herschel selected galaxies within the Great Observatories Origins Deep Survey-South and the Cosmic Evolution Survey fields in the framework of the Photodetector Array Camera and Spectrometer (PACS) Evolutionary Probe project. Starting from the rich multiwavelength photometric data sets available in both fields, we perform a broad-band spectral energy distribution decomposition to disentangle the possible active galactic nucleus (AGN) contribution from that related to the host galaxy. We find that 37 per cent of the Herschel-selected sample shows signatures of nuclear activity at the 99 per cent confidence level. The probability of revealing AGN activity increases for bright (L 1−1000 > 10 11 L ? ) star-forming galaxies at z > 0.3, becoming about 80 per cent for the brightest (L 1−1000 > 10 12 L ? ) Infrared (IR) galaxies at z≄1. Finally, we reconstruct the AGN bolometric luminosity function and the supermassive black hole growth rate across cosmic time up to z ∌ 3 from a far-IR perspective. This work shows general agreement with most of the panchromatic estimates from the literature, with the global black hole growth peaking at z ∌ 2 and reproducing the observed local black hole mass density with consistent values of the radiative efficiency Erad (∌0.07)
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