3,391 research outputs found
Communities of Practice in the Public-Private-Partnership Sector for Neglected Diseases Drug Development: the Importance of Mindset Mapping
This research article explores the mindsets of Public-Private Partnerships and Clinical Trials Organizations (CTOs) and the potential conflicts when working on drug discovery and development in the Third World global infectious diseases sector. A Communities-of-Practice (CoP) approach has been adopted to more fully explore the underlying values, attitudes and practices of these two future partners. This exploratory study suggests that future collaboration will be dependent on the two communities understanding and interpretation of each others‟ sustainability drug development drivers. The authors present secondary research findings that suggest the positive contribution that cognitive mapping of a community‟s sense-making can have in understanding the community‟s likely engagement in any future joint enterprise. Proposed future research will explore the underlying sustainability drivers that may both push and pull CTOs to engage in future global infectious diseases discovery and development projects. The article concludes by discussing the implications for future sustainable drug development projects involving PPPs and potential new strategic partners
Parity Violation in Astrophysics
Core collapse supernovae are gigantic explosions of massive stars that
radiate 99% of their energy in neutrinos. This provides a unique opportunity
for large scale parity or charge conjugation violation. Parity violation in a
strong magnetic field could lead to an asymmetry in the neutrino radiation and
recoil of the newly formed neutron star. Charge conjugation violation in the
neutrino-nucleon interaction reduces the ratio of neutrons to protons in the
neutrino driven wind above the neutron star. This is a problem for r-process
nucleosynthesis in this wind. On earth, parity violation is an excellent probe
of neutrons because the weak charge of a neutron is much larger than that of a
proton. The Parity Radius Experiment (PREX) at Jefferson Laboratory aims to
precisely measure the neutron radius of Pb with parity violating
elastic electron scattering. This has many implications for astrophysics,
including the structure of neutron stars, and for atomic parity nonconservation
experiments.}Comment: 4 pages, 2 figures, proceedings of PAVI04 conference in Grenoble,
Franc
Food choice and diet of the bearded vulture Gypaetus barbatus in southern Africa
When offered a selection of food items, bearded vultures Gypaetus barbatus in southern Africa chose bones in preference to meat or to feeding from a fleshed carcass. Once a carcass had been stripped of soft tissue by Gyps vultures, bearded vultures disarticulated sections or individual bones (depending on the size of the dead animal) in the order: limbs, ribs, vertebrae, skull. Their overall diet was estimated as 70% bone with marrow, 25% meat and 5% skin. This diet is about 15% higher in energy than an equivalent mass of meat. Of 683 identified prey items from five sources of data, over 80% consisted of domestic livestock; about 60% of this was sheep and goats. Even birds nesting within conservation areas derived more than half of their food from domestic stock which they found by foraging over adjacent commercial and subsistence farming areas. Bearded vultures obtain all their food by scavenging, and reports of attacks on live animals and even humans are rejected
Biodiversity of nematode assemblages from the region of the Clarion-Clipperton Fracture Zone, an area of commercial mining interest
BACKGROUND: The possibility for commercial mining of deep-sea manganese nodules is currently under exploration in the abyssal Clarion-Clipperton Fracture Zone. Nematodes have potential for biomonitoring of the impact of commercial activity but the natural biodiversity is unknown. We investigate the feasibility of nematodes as biomonitoring organisms and give information about their natural biodiversity. RESULTS: The taxonomic composition (at family to genus level) of the nematode fauna in the abyssal Pacific is similar, but not identical to, the North Atlantic. Given the immature state of marine nematode taxonomy, it is not possible to comment on the commonality or otherwise of species between oceans. The between basin differences do not appear to be directly linked to current ecological factors. The abyssal Pacific region (including the Fracture Zone) could be divided into two biodiversity subregions that conform to variations in the linked factors of flux to the benthos and of sedimentary characteristics. Richer biodiversity is associated with areas of known phytodetritus input and higher organic-carbon flux. Despite high reported sample diversity, estimated regional diversity is less than 400 species. CONCLUSION: The estimated regional diversity of the CCFZ is a tractable figure for biomonitoring of commercial activities in this region using marine nematodes, despite the immature taxonomy (i.e. most marine species have not been described) of the group. However, nematode ecology is in dire need of further study
Diffeomorphisms as Symplectomorphisms in History Phase Space: Bosonic String Model
The structure of the history phase space of a covariant field system
and its history group (in the sense of Isham and Linden) is analyzed on an
example of a bosonic string. The history space includes the time map
from the spacetime manifold (the two-sheet) to a
one-dimensional time manifold as one of its configuration variables. A
canonical history action is posited on such that its restriction to
the configuration history space yields the familiar Polyakov action. The
standard Dirac-ADM action is shown to be identical with the canonical history
action, the only difference being that the underlying action is expressed in
two different coordinate charts on . The canonical history action
encompasses all individual Dirac-ADM actions corresponding to different choices
of foliating . The history Poisson brackets of spacetime fields
on induce the ordinary Poisson brackets of spatial fields in the
instantaneous phase space of the Dirac-ADM formalism. The
canonical history action is manifestly invariant both under spacetime
diffeomorphisms Diff and temporal diffeomorphisms Diff. Both of
these diffeomorphisms are explicitly represented by symplectomorphisms on the
history phase space . The resulting classical history phase space
formalism is offered as a starting point for projection operator quantization
and consistent histories interpretation of the bosonic string model.Comment: 45 pages, no figure
Sand moisture as a factor determining depth of burrowing in the oniscid isopod Tylos granulatus Krauss
Tylos granulatus, a sandy-beach isopod, prefers an environmental moisture range exceeding 3,4% but less than 13%. The depths to which the animals burrow are, at least partly, determined by the moisture gradient in the sand. They are, however, incapable of burrowing into lotally dry sand. Animals alter their position in the sand in response to changes in moisture content so as to ensure exposure to suitable conditions
Correlated GNSS and temperature measurements at 10-minute intervals on the Severn Suspension Bridge
Global Navigation Satellite System (GNSS) data were gathered on the 998-m-long Severn Suspension Bridge main span. The antennas were located on the tops of the four support towers, as well as five locations on the suspension cables; data were gathered at rates of 10 and 20 Hz. In addition, air and steel temperatures were gathered every 10 min. The GNSS data were processed in an On The Fly manner relative to a reference receiver located on a fixed position adjacent to the Bridge, and the resulting dataset was compared to the air and steel temperature data measurements, and correlations reported. Moving average filters that eliminate short-term movements due to wind loading and traffic loading were applied to the GNSS data, resulting in the longer-term deflections due to temperature changes every 10 min. The temperature over the 3 days varied by up to 10 °C, and movements of the order of decimetres were seen. Clear numerical correlations between the changes in temperature and the changes in height are presented when analysed at these 10-min intervals, suggesting that temperature compensation in structural health monitoring systems could be readily applied, resulting in a sustainable structure
Renormalon Singularities of the QCD Vacuum Polarization Function to Leading Order in
We explicitly determine the residues and orders of all the ultra-violet (UV)
and infra-red (IR) renormalon poles in the Borel plane for the QCD vacuum
polarization function (Adler D-function), to leading order in an expansion in
the number of quark flavours, . The singularity structure is precisely
as anticipated on general grounds. In particular, the leading IR renormalon is
absent, in agreement with operator product expansion ideas. There is a curious
and unexplained symmetry between the third and higher UV and IR renormalon
residues. We are able to sum up separately UV and IR contributions to obtain
closed form results involving -functions. We argue that the leading UV
renormalon should have a more complicated structure than conventionally
assumed. The disappearance of IR renormalons in flavour-saturated SU() QCD
is shown to occur for or 9.Comment: 22 pages of LaTeX, revisions to this paper are mainly typographica
Quantum inequalities in two dimensional curved spacetimes
We generalize a result of Vollick constraining the possible behaviors of the
renormalized expected stress-energy tensor of a free massless scalar field in
two dimensional spacetimes that are globally conformal to Minkowski spacetime.
Vollick derived a lower bound for the energy density measured by a static
observer in a static spacetime, averaged with respect to the observers proper
time by integrating against a smearing function. Here we extend the result to
arbitrary curves in non-static spacetimes. The proof, like Vollick's proof, is
based on conformal transformations and the use of our earlier optimal bound in
flat Minkowski spacetime. The existence of such a quantum inequality was
previously established by Fewster.Comment: revtex 4, 5 pages, no figures, submitted to Phys. Rev. D. Minor
correction
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