262 research outputs found
Insider research, the process and practice : issues arising from professionals conducting research within their own working environments
This thesis explores the chaotic, dynamic, ambiguous, complex and confusing world of the insider researcher. The proliferating species of insider researcher is common in public sector organisations and is particularly prevalent among post-graduate students who have combined study with work. Insider researchers range from the in-house researcher employed to conduct research to those who are conducting research in addition to their normal duties. This thesis, through five illustrative case-studies, discusses, reflects upon, explains, and clarifies the possibilities, limitations and the issues arising from a consideration of the practice of professionals conducting research in the large government education system in Victoria. The central focus of this thesis, that of exploring issues arising from professionals conducting research in their own working environments, has an importance that hitherto has had little direct recognition in the qualitative education research literature. And yet the practice of insider research is common and has a potentially large impact on the nature of the decision making process in public sector organisations. This relative invisibility in the social research literature of a discussion of issues relating to insider research demands to be made more visible. It is both useful and necessary to explore the particular possibilities, conditions and challenges of insiders conducting research in public organisations as the practice of insider research contines to grow. This thesis adds to the literature by locating insider research in a discussion of the wider soial context of ideology, culture, relationships, politics, language and meaning, and the decision-making process
The ELIXR Galaxy Survey. II: Baryons and Dark Matter in an Isolated Elliptical Galaxy
The Elliptical Isolated X-ray (ElIXr) Galaxy Survey is a volume-limited
(<110Mpc) study of optically selected, isolated, Lstar elliptical galaxies, to
provide an X-ray census of galaxy-scale (virial mass, Mvir < 1e13 Msun)
objects, and identify candidates for detailed hydrostatic mass modelling. In
this paper, we present a Chandra and XMM study of one such candidate, NGC1521,
and constrain its distribution of dark and baryonic matter. We find a
morphologically relaxed hot gas halo, extending almost to R500, that is well
described by hydrostatic models similar to the benchmark, baryonically closed,
Milky Way-mass elliptical galaxy NGC720. We obtain good constraints on the
enclosed gravitating mass (M500=3.8e12+/-1e12 Msun, slightly higher than
NGC\thin 720), and baryon fraction (fb500=0.13+/-0.03). We confirm at 8.2-sigma
the presence of a dark matter (DM) halo consistent with LCDM. Assuming a
Navarro-Frenk-White DM profile, our self-consistent, physical model enables
meaningful constraints beyond R500, revealing that most of the baryons are in
the hot gas. Within the virial radius, fb is consistent with the Cosmic mean,
suggesting that the predicted massive, quasi-hydrostatic gas halos may be more
common than previously thought. We confirm that the DM and stars conspire to
produce an approximately powerlaw total mass profile (rho \propto r^-alpha)
that follows the recently discovered scaling relation between alpha and optical
effective radius. Our conclusions are insensitive to modest, observationally
motivated, deviations from hydrostatic equilibrium. Finally, after correcting
for the enclosed gas fraction, the entropy profile is close to the self-similar
prediction of gravitational structure formation simulations, as observed in
massive galaxy clusters.Comment: Accepted for publication in the Astrophysical Journal. Minor
modifications to match accepted version. Conclusions unchanged. 18 pages, 11
figures and 3 table
Toward a Multi-Scale Computational Model of Arterial Adaptation in Hypertension: Verification of a Multi-Cell Agent Based Model
Agent-based models (ABMs) represent a novel approach to study and simulate complex mechano chemo-biological responses at the cellular level. Such models have been used to simulate a variety of emergent responses in the vasculature, including angiogenesis and vasculogenesis. Although not used previously to study large vessel adaptations, we submit that ABMs will prove equally useful in such studies when combined with well-established continuum models to form multi-scale models of tissue-level phenomena. In order to couple agent-based and continuum models, however, there is a need to ensure that each model faithfully represents the best data available at the relevant scale and that there is consistency between models under baseline conditions. Toward this end, we describe the development and verification of an ABM of endothelial and smooth muscle cell responses to mechanical stimuli in a large artery. A refined rule-set is proposed based on a broad literature search, a new scoring system for assigning confidence in the rules, and a parameter sensitivity study. To illustrate the utility of these new methods for rule selection, as well as the consistency achieved with continuum-level models, we simulate the behavior of a mouse aorta during homeostasis and in response to both transient and sustained increases in pressure. The simulated responses depend on the altered cellular production of seven key mitogenic, synthetic, and proteolytic biomolecules, which in turn control the turnover of intramural cells and extracellular matrix. These events are responsible for gross changes in vessel wall morphology. This new ABM is shown to be appropriately stable under homeostatic conditions, insensitive to transient elevations in blood pressure, and responsive to increased intramural wall stress in hypertension
A Census of Baryons and Dark Matter in an Isolated, Milky Way-sized Elliptical Galaxy
We present a study of the dark and luminous matter in the isolated elliptical
galaxy NGC720, based on deep X-ray observations made with Chandra and Suzaku.
The gas is reliably measured to ~R2500, allowing us to place good constraints
on the enclosed mass and baryon fraction (fb) within this radius
(M2500=1.6e12+/-0.2e12 Msun, fb(2500)=0.10+/-0.01; systematic errors are
<~20%). The data indicate that the hot gas is close to hydrostatic, which is
supported by good agreement with a kinematical analysis of the dwarf satellite
galaxies. We confirm a dark matter (DM) halo at ~20-sigma. Assuming an NFW DM
profile, our physical model for the gas distribution enables us to obtain
meaningful constraints at scales larger than R2500, revealing that most of the
baryons are in the hot gas. We find that fb within Rvir is consistent with the
Cosmological value, confirming theoretical predictions that a ~Milky Way-mass
(Mvir=3.1e12+/-0.4e12 Msun) galaxy can sustain a massive, quasi-hydrostatic gas
halo. While fb is higher than the cold baryon fraction typically measured in
similar-mass spiral galaxies, both the gas fraction (fg) and fb in NGC720 are
consistent with an extrapolation of the trends with mass seen in massive galaxy
groups and clusters. After correcting for fg, the entropy profile is close to
the self-similar prediction of gravitational structure formation simulations,
as observed in galaxy clusters. Finally, we find a strong heavy metal abundance
gradient in the ISM similar to those observed in massive galaxy groups.Comment: 23 pages, 13 figures, 4 tables. Accepted for publication in the
Astrophysical Journal. Minor modifications to match accepted version.
Conclusions unchange
Globalising assessment: an ethnography of literacy assessment, camels and fast food in the Mongolian Gobi
What happens when standardised literacy assessments travel globally? The paper presents an ethnographic account of adult literacy assessment events in rural Mongolia. It examines the dynamics of literacy assessment in terms of the movement and re-contextualisation of test items as they travel globally and are received locally by Mongolian respondents. The analysis of literacy assessment events is informed by Goodwin’s ‘participation framework’ on language as embodied and situated interactive phenomena and by Actor Network Theory. Actor Network Theory (ANT) is applied to examine literacy assessment events as processes of translation shaped by an ‘assemblage’ of human and non-human actors (including the assessment texts)
Amplification of Black Vulture (\u3ci\u3eCoragyps atratus\u3c/i\u3e) DNA from regurgitated food pellets
Studies that rely on noninvasive collection of DNA for birds often use feces or feathers. Some birds, such as vultures, regurgitate undigested matter in the form of pellets that are commonly found under roost sites. Our research demonstrates that regurgitated pellets are a viable, noninvasive source of DNA for molecular ecology studies of vultures. Our objectives were to amplify 5 microsatellite loci designed for distinguishing Turkey Vultures (Cathartes aura) and Black Vultures (Coragyps atratus) in a single, multiplexed PCR, and to determine how long the target nuclear DNA persists after a vulture pellet is regurgitated and exposed to the environment. We collected pellets from captive Black Vultures and placed them in an outdoor aviary for a maximum estimated total of 12, 24, 36, or 48 h. We swabbed pellet surfaces for extraction and amplified vulture DNA using the panel of markers. All amplified alleles fell within predicted ranges of Black Vultures for all 5 loci, supporting the use of this microsatellite panel for vulture species identification. Overall amplification success for samples collected 0–12 h after regurgitation was 82.3%. Pellets collected 12–24 h, 24–36 h, and 36–48 h after regurgitation had only 18%, 10.2%, and 4.5% amplification success, respectively, which may have been due to a rain event. Our approach will be useful for noninvasive genetic sampling targeting nuclear DNA. These results should encourage noninvasive genetic sampling studies of other species that regurgitate pellets, such as raptors, water birds, or shorebirds
Landscape transformations produce favorable roosting conditions for turkey vultures and black vultures
Recent increases in turkey vulture (Cathartes aura) and black vulture (Coragyps atratus) populations in North America have been attributed in part to their success adapting to human-modified landscapes. However, the capacity for such landscapes to generate favorable roosting conditions for these species has not been thoroughly investigated. We assessed the role of anthropogenic and natural landscape elements on roosting habitat selection of 11 black and 7 turkey vultures in coastal South Carolina, USA using a GPS satellite transmitter dataset derived from previous research. Our dataset spanned 2006–2012 and contained data from 7916 nights of roosting. Landscape fragmentation, as measured by land cover richness, influenced roosting probability for both species in all seasons, showing either a positive relationship or peaking at intermediate values. Roosting probability of turkey vultures was maximized at intermediate road densities in three of four seasons, and black vultures showed a positive relationship with roads in fall, but no relationship throughout the rest of the year. Roosting probability of both species declined with increasing high density urban cover throughout most of the year. We suggest that landscape transformations lead to favorable roosting conditions for turkey vultures and black vultures, which has likely contributed to their recent proliferations across much of the Western Hemisphere
Using Noninvasive Genetics for Estimating Density and Assessing Diet of Urban and Rural Coyotes in Florida, USA
Coyotes (Canis latrans) are expanding their range and due to conflicts with the public and concerns of Coyotes affecting natural resources such as game or sensitive species, there is interest and often a demand to monitor Coyote populations. A challenge to monitoring is that traditional invasive methods involving live-capture of individual animals are costly and can be controversial. Natural resource management agencies can benefit from contemporary noninvasive genetic sampling approaches aimed at determining key aspects of Coyote ecology (e.g., population density and food habits). However, the efficacy of such approaches under different environmental conditions is poorly understood. Our objectives were to 1) examine accumulation and nuclear DNA degradation rates of Coyote scats in metropolitan and rural sites in Florida to help optimize methods to estimate population density; and 2) explore new genetic methods for determining diet of Coyotes based on vertebrate, plant, and invertebrate species DNA identified in scat. Recently developed DNA metabarcoding approaches make it possible to simultaneously identify DNA from multiple prey species in predator scat samples, but an exploration of this tool for assessing Coyote diet has not been pursued. We observed that scat accumulation rates (0.02 scats/km/day) did not vary between sites and fecal DNA amplification success decreased and genotyping errors increased over time with exposure to sun and precipitation. DNA sampling allowed us to generate a Coyote density estimate for the urban environment of eight Coyotes per 100 km2, but lack of recaptures in the rural area precluded density estimation. DNA metabarcoding showed promise for assessing diet contributions of vertebrate species to Coyote diet. Feral Swine (Sus scrofa) were detected as prey at higher frequencies than previously reported. We identify several considerations that can be used to optimize future noninvasive sampling efforts for Coyotes in the southeastern United States. We also discuss strengths and drawbacks of utilizing DNA metabarcoding for assessing diet of generalist carnivores such as Coyotes
Conspecific chemical cues facilitate mate trailing by invasive Argentine black and white tegus
Squamate reptiles (snakes and lizards) rely on chemical cues from conspecifics to search the environment for potential mates. How such cues are used by invasive species to facilitate reproduction, especially seasonally, is a key question that can inform management practices. The Argentine black and white tegu (Salvator merianae) is an invasive reptile species in south Florida threatening native fauna in biodiverse regions such as Everglades National Park. While some information exists on the reproductive ecology of this species in its native range in South America, the chemical ecology of S. merianae is unclear especially in its invasive range. By testing both male (n = 7) and female (n = 7) tegus in a Y-maze apparatus, we assessed if either sex follows chemical trails left by conspecifics and if behaviors were sex- or season-specific. We conducted three types of trials where conspecifics created odor trails: Male-only (male scent only in base and one arm of Y), Female-only, and Male vs. female. Males did not preferentially follow scent trails from either sex, but they did differentially investigate conspecific scent from both sexes. Seasonally, males showed increased rates of chemosensory sampling (rates of tongue-flicking) during the spring (breeding season; March-May) compared to fall (non-breeding season; September-November). Males also had reduced turning and pausing behavior while trailing in the spring. Female tegus exhibited stronger conspecific trailing abilities than males, following both male and female scent trails, and they explored the maze less before making an arm choice. Females also investigated the scent trails intensely compared to males (more passes in scented arms, more time with scent trails). Our results demonstrate for the first time that females of an invasive reptile species can follow conspecific scent trails. Given the strong female responses to odor, sex-specific targeting of tegus via application of a conspecific chemical cue in traps could enhance removal rates of females during the breeding season
Comparison of routine health management information system versus enhanced inpatient malaria surveillance for estimating the burden of malaria among children admitted to four hospitals in Uganda.
The primary source of malaria surveillance data in Uganda is the Health Management Information System (HMIS), which does not require laboratory confirmation of reported malaria cases. To improve data quality, an enhanced inpatient malaria surveillance system (EIMSS) was implemented with emphasis on malaria testing of all children admitted in select hospitals. Data were compared between the HMIS and the EIMSS at four hospitals over a period of 12 months. After the implementation of the EIMSS, over 96% of admitted children under 5 years of age underwent laboratory testing for malaria. The HMIS significantly overreported the proportion of children under 5 years of age admitted with malaria (average absolute difference = 19%, range = 8-27% across the four hospitals) compared with the EIMSS. To improve the quality of the HMIS data for malaria surveillance, the National Malaria Control Program should, in addition to increasing malaria testing rates, focus on linking laboratory test results to reported malaria cases
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