1,876 research outputs found
Estimation of genetic parameters for height using spatial analysis in Tsuga heterophylla full-sibling family trials in British Columbia
Non-spatial and spatial analyses were carried out to study the effects on genetic parameters in ten-year height growth data across two series of 10 large second-generation full-sib progeny trials of western hemlock [Tsuga heterophylla (Raf.) Sarg.] in British Columbia. To account for different and complex patterns of environmental heterogeneity, spatial single trial analyses were conducted using an individual-tree mixed model with a two-dimensional smoothing surface with tensor product of B-spline bases. The spatial single trial analysis, in all cases, showed sizeable lower Deviance Information Criterion values relative to the non-spatial analysis. Also, fitting a surface displayed a consistent reduction in the posterior mean as well as a decrease in the standard deviations of error variance, no appreciable changes in the additive variance, an increase of individual narrow-sense heritability, and accuracy of breeding values. The tensor product of cubic basis functions of B-spline based on a mixed model framework does provide a useful new alternative to model different and complex patterns of spatial variability within sites in forest genetic trials. Individual narrow-sense heritabilities estimates from the spatial single trial analyses were low (average of 0.06), but typical of this species. Estimated dominance relative to additive variances were unstable across sites (from 0.00 to 1.59). The implications of these estimations will be discussed with respect to the western hemlock genetic improvement program in British Columbia.Fil: Cappa, Eduardo Pablo. British Columbia Ministry of Forests and Range; Canadá. University of British Columbia; Canadá. Instituto Nacional de TecnologÃa Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Yanchuk, A. D.. British Columbia Ministry of Forests and Range; CanadáFil: Cartwright, C. V.. British Columbia Ministry of Forests and Range; Canad
Molecular gas associated with IRAS 10361-5830
We analyze the distribution of the molecular gas and the dust in the
molecular clump linked to IRAS 10361-5830, located in the environs of the
bubble-shaped HII region Gum 31 in the Carina region, with the aim of
determining the main parameters of the associated material and investigating
the evolutionary state of the young stellar objects identified there.
Using the APEX telescope, we mapped the molecular emission in the J=3-2
transition of three CO isotopologues, 12CO, 13CO and C18O, over a 1.5' x 1.5'
region around the IRAS position. We also observed the high density tracers CS
and HCO+ toward the source. The cold dust distribution was analyzed using
submillimeter continuum data at 870 \mu\ obtained with the APEX telescope.
Complementary IR and radio data at different wavelengths were used to complete
the study of the ISM.
The molecular gas distribution reveals a cavity and a shell-like structure of
~ 0.32 pc in radius centered at the position of the IRAS source, with some
young stellar objects (YSOs) projected onto the cavity. The total molecular
mass in the shell and the mean H volume density are ~ 40 solar masses and
~(1-2) x 10 cm, respectively. The cold dust counterpart of the
molecular shell has been detected in the far-IR at 870 \mu\ and in Herschel
data at 350 \mu. Weak extended emission at 24 \mu\ from warm dust is projected
onto the cavity, as well as weak radio continuum emission.
A comparison of the distribution of cold and warm dust, and molecular and
ionized gas allows us to conclude that a compact HII region has developed in
the molecular clump, indicating that this is an area of recent massive star
formation. Probable exciting sources capable of creating the compact HII region
are investigated. The 2MASS source 10380461-5846233 (MSX G286.3773-00.2563)
seems to be responsible for the formation of the HII region.Comment: Accepted in A&A. 11 pages, 10 Postscript figure
Unveiling the molecular environment of the ring nebula RCW 78
We present a study of the ionized, neutral atomic, and molecular gas
associated with the ring nebula RCW 78 around the WR star HD 117688 (= WR 55).
We based our study on CO observations carried out with the SEST and NANTEN
telescopes. We report the detection of molecular gas with velocities in the
range -56 to -33 km/s. The CO emission is mainly connected to the western
section, with a total molecular mass of 1.3 x 10^5 solar masses. The analysis
of the HI gas distribution reveals the HI envelope of the molecular cloud,
while the radio continuum emission shows a ring-like structure, which is the
radio counterpart of the optical nebula. The gas distribution is compatible
with the western section of RCW 78 having originated in the photodissociation
and ionization of the molecular gas by HD 117688, and with the action of the
stellar winds of the WR star. A number of infrared point sources classified as
YSO candidates showed that stellar formation activity is present in the
molecular gas linked to the nebula. The fact that the expansion of the bubble
have triggered star formation in this region can not be discarded.Comment: 15 pages, 11 Postscript figures, to be published in A&
Visitor-sensing: Involving the crowd in cultural heritage organizations
As organizations are increasingly involving individuals across their boundaries in the generation of new knowledge, crowd involvement can also be beneficial to cultural heritage organizations. We argue that in an "Open Innovation in Science" approach, visitors can contribute to generate new scientific knowledge concerning their behavior and preferences, by which museum managers can re-design the cultural offerings of their institutions in ways that generate major economic and social impacts. Accordingly, we advance visitor-sensing as a novel framework in which museum managers leverage digital technologies to collect visitors' ideas, preferences, and feedback in order to improve path design and the organization of artwork in exhibitions, and to shape a more satisfying museum experience for visitors. We contend that visitor-sensing has the potential to yield higher numbers of visitors, with positive impacts in terms of increased revenues and increased literacy of the general public, thus benefiting the economic and social sustainability of cultural organizations towards the achievement of the Sustainable Development Goals outlined in the Agenda 2030
Rethinking recognition: social context in adult life rather than early experience shapes recognition in a social wasp
Social recognition represents the foundation of social living. To what extent social recognition is hard-wired by early-life experience or flexible and influenced by social context of later life stages is a crucial question in animal behaviour studies. Social insects have represented classic models to investigate the subject, and the acknowledged idea is that relevant information to create the referent template for nest-mate recognition (NMR) is usually acquired during an early sensitive period in adult life. Experimental evidence, however, highlighted that other processes may also be at work in creating the template and that such a template may be updated during adult life according to social requirements. However, currently, we lack an ad hoc experiment testing the alternative hypotheses at the basis of NMR ontogeny in social insects. Thus, to investigate the mechanisms underlying the ontogeny of NMR in Polistes wasps, a model genus in recognition studies, and their different role in determining recognition abilities, we subjected Polistes dominula workers to different olfactory experiences in different phases of their life before inserting them into the social environment of a novel colony and testing them in recognition bioassays. Our results show that workers develop their NMR abilities based on their social context rather than through pre-imaginal and early learning or self-referencing. Our study demonstrates that the social context represents the major component shaping recognition abilities in a social wasp, therefore shedding new light on the ontogeny of recognition in paper wasps and prompting the reader to rethink about the traditional knowledge at the basis of the recognition in social insects. This article is part of the theme issue 'Signal detection theory in recognition systems: from evolving models to experimental tests'
HJB Equations and Stochastic Control on Half-Spaces of Hilbert Spaces
In this paper, we study a first extension of the theory of mild solutions for Hamilton–Jacobi–Bellman (HJB) equations in Hilbert spaces to the case where the domain is not the whole space. More precisely, we consider a half-space as domain, and a semilinear HJB equation. Our main goal is to establish the existence and the uniqueness of solutions to such HJB equations, which are continuously differentiable in the space variable. We also provide an application of our results to an exit-time optimal control problem, and we show that the corresponding value function is the unique solution to a semilinear HJB equation, possessing sufficient regularity to express the optimal control in feedback form. Finally, we give an illustrative example
Statistical analysis of three series of daily rainfall in North-Western Italy
In this work we study three long series of daily rainfall measured in North-Western Italy. We analyze the global statistical properties of the three data sets and we discuss both the seasonal distribution of rainfall intensity and the long-term variation in rainfall properties. We show that the three series display a
vanishingly small autocorrelation for periods longer than one or two days, consistent with the absence of multifractality in these records. These time series are largely consistent with the output of a simple
chain-dependent stochastic process
Modulation of the lexical-semantic network by auditory semantic priming: An event-related functional MRI study
The current event-related fMRI study specifies the neuroanatomical correlates of semantic priming and differences in semantic relation types using an auditory primed lexical decision task (LDT). Word pairs consisted of different relation types, associations (key–chain), pure categorical relations (cow–dog), and unrelated words (table–window), as well as word–pseudoword (way–tinne) and pseudoword–pseudoword (ahurn–döva) pairs. The factor lexical status, i.e., the processing of words compared to pseudowords, was associated with activation in the middle temporal gyri and the left striatum. The factor relatedness, i.e., the contrast between unrelated and related target words, was associated with increased activation of the left inferior frontal gyrus, the deep frontal operculum bilaterally, and the middle frontal gyri. A direct contrast between the two semantic relation types indicated that the processing of purely categorical compared to associative information recruits the right precuneus, the isthmus gyrus cinguli, and the cuneus, suggesting more effortful processing of the former information type. The present data show that the factors lexical status, semantic relatedness, and type of semantic relation in a primed LDT modulate the hemodynamic response in cerebral areas that subserve auditory word recognition and subsequent lexical–semantic processing
Sh2-205: II. Its quiescent stellar formation activity
We present a study of active stellar forming regions in the environs of the
HII region Sh2-205. The analysis is based on data obtained from point source
catalogues and images extracted from 2MASS, MSX, and IRAS surveys.
Complementary data are taken from CO survey. The identification of primary
candidates to stellar formation activity is made following colour criteria and
the correlation with molecular gas emission.
A number of stellar formation tracer candidates are projected on two
substructures of the HII region: SH148.83-0.67 and SH149.25-0.00. However, the
lack of molecular gas related to these structures casts doubts on the nature of
the sources. Additional infrared sources may be associated with the HI shell
centered at (l,b) = (149\degr 0\arcmin, -1\degr 30\arcmin).
The most striking active area was found in connection to the HII region LBN
148.11-0.45, where stellar formation candidates are projected onto molecular
gas. The analytical model to the "collect and collapse" process shows that
stellar formation activity could have been triggered by the expansion of this
HII region.Comment: Accepted for publication in MNRAS, 10 pages, 5 figures, 5 table
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