292 research outputs found
Human Activity Helps Prey Win the Predator-Prey Space Race
Predator-prey interactions, including between large mammalian wildlife species, can be represented as a “space race”, where prey try to minimize and predators maximize spatial overlap. Human activity can also influence the distribution of wildlife species. In particular, high-human disturbance can displace large carnivore predators, a trait-mediated direct effect. Predator displacement by humans could then indirectly benefit prey species by reducing predation risk, a trait-mediated indirect effect of humans that spatially decouples predators from prey. The purpose of this research was to test the hypothesis that high-human activity was displacing predators and thus indirectly creating spatial refuge for prey species, helping prey win the “space race”. We measured the occurrence of eleven large mammal species (including humans and cattle) at 43 camera traps deployed on roads and trails in southwest Alberta, Canada. We tested species co-occurrence at camera sites using hierarchical cluster and nonmetric multidimensional scaling (NMS) analyses; and tested whether human activity, food and/or habitat influenced predator and prey species counts at camera sites using regression tree analysis. Cluster and NMS analysis indicated that at camera sites humans co-occurred with prey species more than predator species and predator species had relatively low co-occurrence with prey species. Regression tree analysis indicated that prey species were three times more abundant on roads and trails with >32 humans/day. However, predators were less abundant on roads and trails that exceeded 18 humans/day. Our results support the hypothesis that high-human activity displaced predators but not prey species, creating spatial refuge from predation. High-human activity on roads and trails (i.e., >18 humans/day) has the potential to interfere with predator-prey interactions via trait-mediated direct and indirect effects. We urge scientist and managers to carefully consider and quantify the trait-mediated indirect effects of humans, in addition to direct effects, when assessing human impacts on wildlife and ecosystems
Photometric Solutions for Detached Eclipsing Binaries: selection of ideal distance indicators in the SMC
Detached eclipsing binary stars provide a robust one-step distance
determination to nearby galaxies. As a by-product of Galactic microlensing
searches, catalogs of thousands of variable stars including eclipsing binaries
have been produced by the OGLE, MACHO and EROS collaborations. We present
photometric solutions for detached eclipsing binaries in the Small Magellanic
Cloud (SMC) discovered by the OGLE collaboration. The solutions were obtained
with an automated version of the Wilson-Devinney program. By fitting mock
catalogs of eclipsing binaries we find that the normalized stellar radii
(particularly their sum) and the surface brightness ratio are accurately
described by the fitted parameters and estimated standard errors, despite
various systematic uncertainties. In many cases these parameters are well
constrained. In addition we find that systems exhibiting complete eclipses can
be reliably identified where the fractional standard errors in the radii are
small. We present two quantitatively selected sub-samples of eclipsing binaries
that will be excellent distance indicators. These can be used both for
computation of the distance to the SMC and to probe its structure. One
particularly interesting binary has a very well determined solution, exhibits
complete eclipses, and is comprised of well detached G-type, class giants.Comment: 29 pages, 12 figures. To be published in Ap
Photometry of VS0329+1250: A New, Short-Period SU Ursae Majoris Star
Time-resolved CCD photometry is presented of the recently-discovered (V~15 at
maximum light) eruptive variable star in Taurus, which we dub VS0329+1250. A
total of ~20 hr of data obtained over six nights reveals superhumps in the
light curves, confirming the star as a member of the SU UMa class of dwarf
novae. The superhumps recur with a mean period of 0.053394(7) days (76.89 min),
which represents the shortest superhump period known in a classical SU UMa
star. A quadratic fit to the timings of superhump maxima reveals that the
superhump period was increasing at a rate given by dP/dt ~ (2.1 +/- 0.8) x
10^{-5} over the course of our observations. An empirical relation between
orbital period and the absolute visual magnitude of dwarf novae at maximum
light, suggests that VS0329+1250 lies at a distance of ~1.2 +/- 0.2 kpc.Comment: V2 - The paper has been modified to incorporate the referee's
comments, and has now been accepted for publication in the PASP. The most
significant change is that we are now able to confirm that the superhump
period was increasing during the course of our observation
Creative Approaches to the Creation of Contemporary Art Objects and Features of their Legal Protection
This study is devoted to the analysis of the current state of legislation of Ukraine and EU countries on copyright protection of works with an unstable form of expression, as well as to determine the features of the legal protection of such objects. The purpose of the article was to explore the existing possibilities in the law of Ukraine and the law of the EU countries for the protection of works with an unstable form of their expression. The article, based on the analysis of international legal acts and national legislation, highlights the elements of protection of works. A significant place in work is devoted to the analysis of theoretical, legislative approaches to the definition of "creativity", "originality", "novelty". It is stated that there is no single waste to the definition of these concepts in the literature and not regulated in the legislation in the field of copyright. A comparative legal analysis of the case-law of the United Kingdom and the United States on the provision of legal protection to works with an unstable form. It is concluded that the normative definition of “creative work”, which is associated exclusively with works of cultural value, is not acceptable for copyright. The article analyses the judicial practice of Ukraine, which has developed in the definition of creative work and illustrates its ambiguity. It is concluded that judges, considering such cases, try to find some stable elements that are inherent in works with an unstable form of expression.
Keywords: Intellectual property law, object of intellectual property law, subjects of intellectual property law
Detection of orbital and superhump periods in Nova V2574 Ophiuchi (2004)
We present the results of 37 nights of CCD unfiltered photometry of nova
V2574 Oph (2004) from 2004 and 2005. We find two periods of 0.14164 d (~3.40 h)
and 0.14773 d (~3.55 h) in the 2005 data. The 2004 data show variability on a
similar timescale, but no coherent periodicity was found. We suggest that the
longer periodicity is the orbital period of the underlying binary system and
that the shorter period represents a negative superhump. The 3.40 h period is
about 4% shorter than the orbital period and obeys the relation between
superhump period deficit and binary period. The detection of superhumps in the
light curve is evidence of the presence of a precessing accretion disk in this
binary system shortly after the nova outburst. From the maximum magnitude -
rate of decline relation, we estimate the decay rate t_2 = 17+/-4 d and a
maximum absolute visual magnitude of M_Vmax = -7.7+/-1.7 mag.Comment: 6 pages, 6 figures, 2 .sty files, AJ accepted, minor change to one of
reference
The Australian bushfires of February 2009: MIPAS observations and GEM-AQ model results
Starting on 7 February 2009, southeast Australia was devastated by large bushfires, which burned an area of about 3000 km<sup>2</sup> on this day alone. This event was extraordinary, because a large number of combustion products were transported into the uppermost troposphere and lower stratosphere within a few days. Various biomass burning products released by the fire were observed by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on the Envisat satellite. We tracked the plume using MIPAS C<sub>2</sub>H<sub>2</sub>, HCN and HCOOH single-scan measurements on a day-to-day basis. The measurements were compared with a high-resolution model run of the Global Environmental Multiscale Air Quality (GEM-AQ) model. Generally there is good agreement between the spatial distribution of measured and modelled pollutants. Both MIPAS and GEM-AQ show a fast southeastward transport of the pollutants to New Zealand within one day. During the following 3–4 days, the plume remained northeastward of New Zealand and was located at altitudes of 15 to 18 km. Thereafter its lower part was transported eastward, followed by westward transport of its upper part. On 17 February the eastern part had reached southern South America and on 20 February the central South Atlantic. On the latter day a second relic of the plume was observed moving eastward above the South Pacific. Between 20 February and the first week of March, the upper part of the plume was transported westward over Australia and the Indian Ocean towards southern Africa. First evidence for entry of the pollutants into the stratosphere was found in MIPAS data of 11 February, followed by larger amounts on 17 February and the days thereafter. From MIPAS data, C<sub>2</sub>H<sub>2</sub>/HCN and HCOOH/HCN enhancement ratios of 0.76 and 2.16 were calculated for the first days after the outbreak of the fires, which are considerably higher than the emission ratios assumed for the model run and at the upper end of values found in literature. From the temporal decrease of the enhancement ratios, mean lifetimes of 16–20 days and of 8–9 days were calculated for measured C<sub>2</sub>H<sub>2</sub> and HCOOH. The respective lifetimes calculated from the model data are 18 and 12 days
In-the-Gap SU UMa-Type Dwarf Nova, Var73 Dra with a Supercycle of about 60 Days
An intensive photometric-observation campaign of the recently discovered SU
UMa-type dwarf nova, Var73 Dra was conducted from 2002 August to 2003 February.
We caught three superoutbursts in 2002 October, December and 2003 February. The
recurrence cycle of the superoutburst (supercycle) is indicated to be 60
d, the shortest among the values known so far in SU UMa stars and close to
those of ER UMa stars. The superhump periods measured during the first two
superoutbursts were 0.104885(93) d, and 0.10623(16) d, respectively. A
0.10424(3)-d periodicity was detected in quiescence. The change rate of the
superhump period during the second superoutburst was , which
is an order of magnitude larger than the largest value ever known. Outburst
activity has changed from a phase of frequent normal outbursts and infrequent
superoutbursts in 2001 to a phase of infrequent normal outbursts and frequent
superoutbursts in 2002. Our observations are negative to an idea that this star
is an related object to ER UMa stars in terms of the duty cycle of the
superoutburst and the recurrence cycle of the normal outburst. However, to
trace the superhump evolution throughout a superoutburst, and from quiescence
more effectively, may give a fruitful result on this matter.Comment: 9 pages, 8 figures, submitted to A&
Innovating transcriptomics for practitioners in freshwater fish management and conservation: best practices across diverse resource-sector users
Thriving freshwater fish populations contribute to people’s economic prosperity and wellbeing. Yet, freshwater fish populations are in critical condition around the globe. Most stressors to freshwater fishes, fisheries, and culture stem from habitat impacts, water-quality issues, and aquatic invasive species. Logistical difficulties of monitoring fish health are compounded by the limitations of conventional (capture-based) sampling methods, which provide only a temporal “snapshot” and generate data lacking in sensitivity and prognostic ability. Here, we propose an innovative genomics approach to develop a health toolkit that will allow resource-sector users to determine the health status of freshwater fishes, including their coping capacity, to environmental stressors. The stress-response transcription profile (STP)-chip is a suite of quantitative gene transcription assays that represents key gene pathways broadly associated with fish functional responses to environmental stress; therefore, the differential expression of well-selected genes can provide sensitive fish-health status indicators. Despite the scientific achievement of using genomics tools, actualizing the toolkit in practice is only successful if resource-sector users have full buy-in. We present seven case studies representing different practitioners and resource users – Indigenous rightsholders, environmental consultants (industry), commercial aquaculture, environmental charities (ENGO), and fishery commissions and managers (government) where each explores the benefits and risks associated with the adoption of a genomics fish-health toolkit. Using a co-production approach, wherein practitioners and resource users are engaged from the outset, these case studies reveal translational pathways that would be needed to overcome barriers to technological adoption and, hence, accelerate the responsible uptake of genomics-based applications in fisheries assessment, management, and conservation
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Summertime stratospheric processes at northern mid-latitudes: comparisons between MANTRA balloon measurements and the Canadian Middle Atmosphere Model
In this paper we report on a study conducted using the Middle Atmospheric Nitrogen TRend Assessment (MANTRA) balloon measurements of stratospheric constituents and temperature and the Canadian Middle Atmosphere Model (CMAM). Three different kinds of data are used to assess the inter-consistency of the combined dataset: single profiles of long-lived species from MANTRA 1998, sparse climatologies from the ozonesonde measurements during the four MANTRA campaigns and from HALOE satellite measurements, and the CMAM climatology. In doing so, we evaluate the ability of the model to reproduce the measured fields and to thereby test our ability to describe mid-latitude summertime stratospheric processes. The MANTRA campaigns were conducted at Vanscoy, Saskatchewan, Canada (52◦ N, 107◦ W)in late August and early September of 1998, 2000, 2002 and 2004. During late summer at mid-latitudes, the stratosphere is close to photochemical control, providing an ideal scenario for the study reported here. From this analysis we find that: (1) reducing the value for the vertical diffusion coefficient in CMAM to a more physically reasonable value results in the model better reproducing the measured profiles of long-lived species; (2) the existence of compact correlations among the constituents, as expected from independent measurements in the literature and from models, confirms the self-consistency of the MANTRA measurements; and (3) the 1998 measurements show structures in the chemical species profiles that can be associated with transport, adding to the growing evidence that the summertime stratosphere can be much more disturbed than anticipated. The mechanisms responsible for such disturbances need to be understood in order to assess the representativeness of the measurements and to isolate longterm trends
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