5,018 research outputs found
Collaborative public procurement: Institutional explanations of legitimised resistance
This paper reports on the barriers to regional collaborative procurement developed from an action research study of five UK public authorities in the emergency services sector. Despite political pressure to procure collaboratively, strategic avoidance responses of institutional logics and symbolic tick boxing legitimise stakeholder resistance to isomorphic forces and entrench operational barriers. The prevailing institutional logics are that regional collaborative procurement is unsuitable and risky, derived from procurement's lack of status and the emotive nature of the emergency services. Symbolic tick boxing is seen through collaboration that is limited to high profile spend categories, enabling organisations to demonstrate compliance while simultaneously retaining local decision-making for less visible, but larger areas of spend. The findings expose choice mechanisms in public procurement by exploring tensions arising from collaborative procurement strategies within, and between, organisations. Multiple stakeholders' perspectives add to current thinking on how organisations create institutional logics to avoid institutional pressure to procure collaboratively and how stakeholders legitimise their actions
MRI: ID-Development of a Hybrid Scanning Fluorescence and Sum Frequency Spectroscopy Imaging Microscope
With this award from the Major Research Instrumentation program (MRI), Michael Mason and colleagues from the Department of Chemistry at the University of Maine will develop a hybrid scanning fluorescence (FL) and sum frequency (SF) spectroscopy imaging microscope. The instrument will be constructed by the addition of sample scanning and FL capability to an existing broadband SF spectrometer. The SF NIR pump source will be used to excite SF at the sample interface, while a modulated Argon ion CW laser will excite FL. These collinear sources will give rise to spatially and temporally correlated SF and FL signals which will be separated and individually detected. The instrument will simultaneously measure the fluorescence and sum frequency to yield information about the localized dynamics of a single particle, i.e. protein, and spatially correlated structural information about the bulk material containing the particle. This yields information about the interaction between the particle and the bulk not accessible by any other method. The proposal will initially investigate test projects including the study of membrane domain structure and membrane-membrane interactions, e,g., correlation of the structure and dynamics of lipid and protein molecules within planar supported lipid bilayers. Successful development of this instrument could lead to major breakthroughs in several fields ranging from surface chemistry and biophysics to nanotechnology and cellular biology
PRELIMINARY EVALUATION OF A GRANULAR TRIMETHACARB FORMULATION FOR DETERRING GRAZING BY AMERICAN COOTS
In a 0.2 ha flight pen, groups of 4 American coots were tested to determine if their grazing activity could be affected by application of a registered granular-trimethacarb insecticide. In the 3 days following treatment (3 kg/ha, a.i.), grazing activity in the treated portions of the 200 m2 experimental plots was reduced an average of 47X. Overall use of the treated areas followed a similar pattern but was less consistent among groups. The addition of methylpyrazine, a strong odorant, produced a strong initial suppression of grazing activity in the treated halves of the plots. However, subsequent rain and a change in the coots\u27 grazing behavior prevented a definitive evaluation of the methylpyrazine treatment. Two birds that died during the trimethacarb-only portion of the study did not have abnormally low levels of brain cholinesterase. However, this finding does not preclude the possibility that they were unable to distinguish treated from untreated grass and consumed lethal amounts of trimethacarb. Additional investigation of methylpyrazine appears warranted; such materials may act to decrease the likelihood that birds will ingest lethal quantities of repellent
Computer graphics interactive workshop for two-dimensional fractals
We present in this study an interactive computer graphics workshop for two-dimensional fractals. The workshop enables the user to learn about fractals through experimentation with the generation of Koch-like fractal curves. A variety of Koch-like fractal curves, Julia sets and the Mandelbrot set are presented as examples. Algorithms are presented for creating the Mandelbrot set and for creating Kock-like fractal curves. Keywords and Phrases: fractals, Kock-like Fractal curves, Julia sets, interactive computer graphicsU.S. Army Combat Development Experimentation
Center (USACDEC) under MIPR ATEC 46-86 and in part by funds provided through the
Commodore Grace Murray Hopper Research Chair in Computer Science at the Naval
Postgraduate School.http://archive.org/details/computergraphicsin00masoN0003986WRDQ200N
The discovery of 2.78 hour periodic modulation of the X-ray flux from globular cluster source Bo 158 in M31
We report the discovery of periodic intensity dips in the X-ray source XMMU
J004314.1+410724, in the globular cluster Bo158 in M31. The X-ray flux was
modulated by ~83% at a period of 2.78 hr (10017 s) in an XMM-Newton observation
taken 2002 Jan 6-7. The X-ray intensity dips show no energy dependence. We
detected weaker dips with the same period in observations taken 2000 June 25
(XMM-Newton) and 1991 June 26 (ROSAT/PSPC). The amplitude of the modulation has
been found to be anticorrelated with source X-ray flux: it becomes lower when
the source intensity rises. The energy spectrum of Bo158 was stable from
observation to observation, with a characteristic cutoff at ~4-6 keV. The
photo-electric absorption was consistent with the Galactic foreground value. No
significant spectral changes were seen in the course of the dips. If the 2.78
hr cycle is the binary period of Bo158 the system is highly compact, with a
binary separation of ~10e11 cm. The association of the source with a globular
cluster, together with spectral parameters consistent with Galactic neutron
star sources, suggests that X-rays are emitted by an accreting neutron star.
The properties of Bo 158 are somewhat reminiscent of the Galactic X-ray sources
exhibiting a dip-like modulations. We discuss two possible mechanisms
explaining the energy-independent modulation observed in Bo 158: i) the
obscuration of the central source by highly ionized material that scatters
X-rays out of the line of sight; ii) partial covering of an extended source by
an opaque absorber which occults varying fractions of the source.Comment: 10 pages, 4 figures, ApJ, submitted, uses emulateapj styl
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Adolescent substance abuse treatment incorporating "Rites of Passage"
This investigation assessed the effectiveness of an adolescent substance abuse treatment program that incorporated "Rites of Passage." Named Gender Based Treatment (GBT), the treatment program sought to address the adolescents' developmental needs through the use of rituals, myth and story telling, and rites of initiation.
Employing quantitative and qualitative analysis, this investigation assessed and described the GBT program over a nine month period. The quantitative data analysis revealed a change in the positive direction after the treatment for most of the subjects. Of the subjects who met the Follow-up Structured Interview criteria, six out of eight reported being alcohol and drug free 30 days following treatment. Two subjects reported relapses and one subject reported a minor incident with the legal system.
The qualitative data collected raised concerns regarding (a) the "common vision" of the staff; (b) the awareness level of the staff regarding the cultural assumptions and the moral/political implications of the GBT; (c) the contradictory messages being sent regarding smoking, gender relations, power, and sexism; and (d) the interest, engagement, and impact of the GBT on the subjects.
This investigation revealed the accuracy in which the GBT matched the recommendations made in the substance abuse literature. It is speculated that an interaction effect between the traditional form of treatment and the new GBT, positively influenced subjects' abstinence and relapse rate, illegal behavior, self-esteem and coping behaviors. Further speculation regarding the theoretical implications for this study point to Social Learning Theory, or modeling as a potent variable. It is hypothesized that the staff members' involvement in the planning and implementing this new form of treatment had a positive influence on the staff as a whole and thereby positively influenced the adolescents in treatment
Novel lines of Pax6-/- embryonic stem cells exhibit reduced neurogenic capacity without loss of viability
<p>Abstract</p> <p>Background</p> <p>Embryonic stem (ES) cells can differentiate into all cell types and have been used extensively to study factors affecting neuronal differentiation. ES cells containing mutations in known genes have the potential to provide useful in vitro models for the study of gene function during neuronal differentiation. Recently, mouse ES cell lines lacking the neurogenic transcription factor Pax6 were reported; neurons derived from these <it>Pax6</it><sup>-/- </sup>ES cells died rapidly after neuronal differentiation in vitro.</p> <p>Results</p> <p>Here we report the derivation of new lines of <it>Pax6</it><sup>-/- </sup>ES cells and the assessment of their ability to survive and differentiate both in vitro and in vivo. Neurons derived from our new <it>Pax6</it><sup>-/- </sup>lines were viable and continued to elaborate processes in culture under conditions that resulted in the death of neurons derived from previously reported <it>Pax6</it><sup>-/- </sup>ES cell lines. The new lines of <it>Pax6</it><sup>-/-</sup>ES cells showed reduced neurogenic potential, mimicking the effects of loss of Pax6 in vivo. We used our new lines to generate <it>Pax6</it><sup>-/- </sup>↔ <it>Pax6</it><sup>+/+ </sup>chimeras in which the mutant cells survived and displayed the same phenotypes as <it>Pax6</it><sup>-/- </sup>cells in <it>Pax6</it><sup>-/- </sup>↔ <it>Pax6</it><sup>+/+ </sup>chimeras made by embryo aggregation.</p> <p>Conclusions</p> <p>We suggest that loss of Pax6 from ES cells reduces their neurogenic capacity but does not necessarily result in the death of derived neurons. We offer these new lines as additional tools for those interested in the generation of chimeras and the analysis of in vitro ES cell models of Pax6 function during neuronal differentiation, embryonic and postnatal development.</p
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