764 resultados para non-local filtering
Resumo:
This article examines efforts to create binding international rules regulating public procurement and considers, in particular, the failure to reach a WTO agreement oil transparency in government procurement. The particular focus of the discussion is the approach taken by Malaysia to these international procurement rules and to the negotiation of an agreement on transparency. Rules governing public procurement directly implicate fundamental arrangements of authority amongst and between different parts of government, its citizens and non-citizens. At the same time, the rules touch upon areas that are particularly sensitive for some developing countries. Many governments use preferences in public procurement to accomplish important redistributive and developmental goals. Malaysia has long used significant preferences in public procurement to further sensitive developmental policies targeted at improving the economic strength of native Malays. Malaysia also has political and legal arrangements substantially at odds with fundamental elements of proposed global public procurement rules. Malaysia has, therefore, been forceful in resisting being bound by international public procurement rules, and has played all important role in defeating the proposed agreement oil transparency. We suggest that our case study has implications beyond procurement. The development of international public procurement rules appears to be guided by many of the same values that guide the broader effort to create a global administrative law. This case study, therefore, has implications for the broader exploration of these efforts to develop a global administrative law, in particular the relationship between such efforts and the interests of developing countries.
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Measles virus (MV) is highly infectious, and has long been thought to enter the host by infecting epithelial cells of the respiratory tract. However, epithelial cells do not express signaling lymphocyte activation molecule (CD150), which is the high-affinity cellular receptor for wild-type MV strains. We have generated a new recombinant MV strain expressing enhanced green fluorescent protein (EGFP), based on a wild-type genotype B3 virus isolate from Khartoum, Sudan (KS). Cynomolgus macaques were infected with a high dose of rMV(KS)EGFP by aerosol inhalation to ensure that the virus could reach the full range of potential target cells throughout the entire respiratory tract. Animals were euthanized 2, 3, 4 or 5 days post-infection (d.p.i., n?=?3 per time point) and infected (EGFP(+)) cells were identified at all four time points, albeit at low levels 2 and 3 d.p.i. At these earliest time points, MV-infected cells were exclusively detected in the lungs by fluorescence microscopy, histopathology and/or virus isolation from broncho-alveolar lavage cells. On 2 d.p.i., EGFP(+) cells were phenotypically typed as large mononuclear cells present in the alveolar lumen or lining the alveolar epithelium. One to two days later, larger clusters of MV-infected cells were detected in bronchus-associated lymphoid tissue (BALT) and in the tracheo-bronchial lymph nodes. From 4 d.p.i. onward, MV-infected cells were detected in peripheral blood and various lymphoid tissues. In spite of the possibility for the aerosolized virus to infect cells and lymphoid tissues of the upper respiratory tract, MV-infected cells were not detected in either the tonsils or the adenoids until after onset of viremia. These data strongly suggest that in our model MV entered the host at the alveolar level by infecting macrophages or dendritic cells, which traffic the virus to BALT or regional lymph nodes, resulting in local amplification and subsequent systemic dissemination by viremia.
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The role of dispersion or van de Waals (VDW) interactions in imidazolium-based room-temperature ionic liquids is studied within the framework of density functional theory, using a recently developed non-empirical functional [M. Dion, H. Rydberg, E. Schroder, D. C. Langreth, and B. I. Lundqvist, Phys. Rev. Lett. 92, 246401 (2004)], as efficiently implemented in the SIESTA code [G. Roman-Perez and J. M. Soler, Phys. Rev. Lett. 103, 096102 (2009)]. We present results for the equilibrium structure and lattice parameters of several crystalline phases, finding a general improvement with respect to both the local density (LDA) and the generalized gradient approximations (GGA). Similar to other systems characterized by VDW bonding, such as rare gas and benzene dimers as well as solid argon, equilibrium distances and volumes are consistently overestimated by approximate to 7%, compared to -11% within LDA and 11% within GGA. The intramolecular geometries are retained, while the intermolecular distances and orientations are significantly improved relative to LDA and GGA. The quality is superior to that achieved with tailor-made empirical VDW corrections ad hoc [M. G. Del Popolo, C. Pinilla, and P. Ballone, J. Chem. Phys. 126, 144705 (2007)]. We also analyse the performance of an optimized version of this non-empirical functional, where the screening properties of the exchange have been tuned to reproduce high-level quantum chemical calculations [J. Klimes, D. Bowler, and A. Michaelides, J. Phys.: Condens. Matter 22, 074203 (2010)]. The results for solids are even better with volumes and geometries reproduced within 2% of experimental data. We provide some insight into the issue of polymorphism of [bmim][Cl] crystals, and we present results for the geometry and energetics of [bmim][Tf] and [mmim][Cl] neutral and charged clusters, which validate the use of empirical force fields. (C) 2011 American Institute of Physics. [doi:10.1063/1.3652897]
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omega Ori (HD37490, HR1934) is a Be star known to have presented variations. In order to investigate the nature and origin of its short-term and mid-term variability, a study is performed of several spectral lines (Halpha, Hdelta, HeI 4471, 4713, 4921, 5876, 6678, CII 4267, 6578, 6583, Mg II 4481, Si III 4553 and Si II 6347), based on 249 high signal-to-noise high-resolution spectra taken with 8 telescopes over 22 consecutive nights during the MuSiCoS (Multi SIte COntinuous Spectroscopy) campaign in November-December 1998. The stellar parameters are revisited and the projected rotational velocity (v sin i = 179 km s(-1)) is redetermined using several methods. With the MuSiCoS 98 dataset, a time series analysis of line-profile variations (LPVs) is performed using the Restricted Local Cleanest (RLC) algorithm and a least squares method. The behaviour of the velocity of the centroid of the lines, the equivalent widths and the apparent vsini for several lines, as well as Violet and Red components of photospheric lines affected by emission (red He i lines, Si II 6347, CII 6578, 6583) are analyzed. The non-radial pulsation (NRP) model is examined using phase diagrams and the Fourier-Doppler Imaging (FDI) method. The LPVs are consistent with a NRP mode with l = 2 or 3, \m\ = 2 with frequency 1.03 cd(-1). It is shown that an emission line outburst occurred in the middle of the campaign. Two scenarios are proposed to explain the behaviour of a dense cloud, temporarily orbiting around the star with a frequency 0.46 c d(-1), in relation to the outburst.
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Half hour exposures using the ESO VLT/FORS1 combination at Paranal in Chile have allowed us to obtain spectra for three B supergiants in the dwarf irregular galaxy NGC 6822. The spectra have been analysed using non-LTE techniques and temperatures, gravities, helium content and abundances have been obtained. Overall the metallicity of NGC 6822 is found to lie between that of the LMC and of the SMC, in agreement with previous observations of H II regions and in contrast to the earlier findings of Massey et al. (1995). The analysis of H-alpha yields estimates of the mass-loss rates and wind momenta. These results demonstrate that significantly longer exposures with the same instruments will allow us to perform quantitative spectroscopy of blue supergiants in galaxies far beyond the Local Group.
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Punching failure is the common failure mode in concrete bridge deck slabs when these structural components are subjected to local patch loads, such as tyre loads. Past research has shown that reinforced concrete slabs in girder–slab type bridges have a load-carrying capacity far greater than the ultimate static loads predicted by traditional design methods, because of the presence of compressive membrane action. However, due to the instability problems from punching failure, it is difficult to predict ultimate capacities accurately in numerical analyses. In order to overcome the instability problems, this paper establishes an efficient non-linear finite-element analysis using the commercial finite-element package Abaqus. In the non-linear finite-element analysis, stabilisation methods were adopted and failure criteria were established to predict the ultimate punching behaviour of deck slabs in composite steel–concrete bridges. The proposed non-linear finite-element analysis predictions showed a good correlation on punching capacities with experimental tests.
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Local computation in join trees or acyclic hypertrees has been shown to be linked to a particular algebraic structure, called valuation algebra.There are many models of this algebraic structure ranging from probability theory to numerical analysis, relational databases and various classical and non-classical logics. It turns out that many interesting models of valuation algebras may be derived from semiring valued mappings. In this paper we study how valuation algebras are induced by semirings and how the structure of the valuation algebra is related to the algebraic structure of the semiring. In particular, c-semirings with idempotent multiplication induce idempotent valuation algebras and therefore permit particularly efficient architectures for local computation. Also important are semirings whose multiplicative semigroup is embedded in a union of groups. They induce valuation algebras with a partially defined division. For these valuation algebras, the well-known architectures for Bayesian networks apply. We also extend the general computational framework to allow derivation of bounds and approximations, for when exact computation is not feasible.
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1. Lough Neagh and Lough Beg Special Protection Area (SPA, hereafter Lough Neagh) is an important non-estuarine site in Britain and Ireland for overwintering wildfowl. Multivariate analysis of the winter counts showed a state-shift in the waterbird community following winter 2000/2001, mostly due to rapid declines in abundance (46–57% declines in the mean mid-winter January counts between 1993–2000 and 2002–2009) of members of the diving duck guild (pochard Aythya ferina, tufted duck Aythya fuligula and goldeneye Bucephala clangula) and coot (Fulica atra), a submerged macrophyte feeder.
2. Only pochard showed correlations between declines at Lough Neagh and those of overall species flyway population indices to suggest that global changes could contribute to declines at the site. However, indices from the Republic of Ireland showed no overall decline in the rest of Ireland. Tufted duck indices at the site were inversely related to indices in Great Britain. Lough Neagh goldeneye indices were positively correlated with indices in the Republic of Ireland and Great Britain, suggesting that short-stopping could contribute to declines at the site. Coot declines at Lough Neagh did not correlate with trends elsewhere, suggesting local factors involved in the decline.
3. These analyses indicate that although there are potentially different explanations for the dramatic declines in these four waterbird species at this site, the simultaneous nature of the declines across two feeding guilds strongly
suggest that local factors (such as loss of submerged macrophytes and benthic invertebrates) were involved. An assessment of the food supply, local disturbance and other factors at Lough Neagh is required to find an explanation for the observed adverse trends in wintering numbers of the affected species.
4. This study highlights the potential of waterbird community structure to reflect the status of aquatic systems, but confirms the need to establish site-specific factors responsible for the observed changes in abundance of key waterbird species at a site.
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Medical geology research has recognised a number of potentially toxic elements (PTEs), such as arsenic, cobalt, chromium, copper, nickel, lead, vanadium, uranium and zinc, known to influence human disease by their respective deficiency or toxicity. As the impact of infectious diseases has decreased and the population ages, so cancer has become the most common cause of death in developed countries including Northern Ireland. This research explores the relationship between environmental exposure to potentially toxic elements in soil and cancer disease data across Northern Ireland. The incidence of twelve different cancer types (lung, stomach, leukaemia, oesophagus, colorectal, bladder, kidney, breast, mesothelioma, melanoma and non melanoma(NM) both basal and squamous, were examined in the form of twenty-five coded datasets comprising aggregates over the 12 year period from 1993 to 2006. A local modelling technique,geographically weighted regression (GWR) is usedto explore the relationship between environmental exposure and cancer disease data. The results show comparisons of the geographical incidence of certain cancers (stomach and NM squamous skin cancer) in relation to concentrations of certain PTEs (arsenic levels in soils and radon were identified). Findings from the research have implications for regional human health risk assessments.
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The traditional training of surgeons focused exclusively on developing knowledge, clinical expertise, and technical (surgical) skills. However, analyses of the reasons for adverse events in surgery have revealed that many underlying causes originate from behavioural or non-technical aspects of performance (eg, poor communication among members of the surgical team) rather than from a lack of surgical (ie, technical) skills. Therefore, technical skills appear to be necessary but not sufficient to ensure patient safety. Paying attention to non-technical skills, such as team working, leadership, situation awareness, decision making, and communication, will increase the likelihood of maintaining high levels of error-free performance. Identification and training of non-technical skills has been developed for high-risk careers, such as civil aviation and nuclear power. Only recently, training in non-technical skills has been adopted by the surgical world and anaesthetists. Non-technical skills need to be tailored to the environment where they are used, and eye surgery has some substantial differences compared with other surgical areas, for example, high volume of surgery, use of local anaesthetics, and very sophisticated equipment. This review highlights the need for identification of the non-technical skills relevant to eye surgeons and promotion of their use in the training of eye surgeons.
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It has long been recognised that dispersal abilities and environmental factors are important in shaping invertebrate communities, but their relative importance for primary soil community assembly has not yet been disentangled. By studying soil communities along chronosequences on four recently emerged nunataks (ice-free land in glacial areas) in Iceland, we replicated environmental conditions spatially at various geographical distances. This allowed us to determine the underlying factors of primary community assembly with the help of metacommunity theories that predict different levels of dispersal constraints and effects of the local environment. Comparing community assembly of the nunataks with that of non-isolated deglaciated areas indicated that isolation of a few kilometres did not affect the colonisation of the soil invertebrates. When accounting for effects of geographical distances, soil age and plant richness explained a significant part of the variance observed in the distribution of the oribatid mites and collembola communities, respectively. Furthermore, null model analyses revealed less co-occurrence than expected by chance and also convergence in the body size ratio of co-occurring oribatids, which is consistent with species sorting. Geographical distances influenced species composition, indicating that the community is also assembled by dispersal, e.g. mass effect. When all the results are linked together, they demonstrate that local environmental factors are important in structuring the soil community assembly, but are accompanied with effects of dispersal that may "override" the visible effect of the local environment.
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We study the interplay between forgetful and memory-keeping evolution enforced on a two-level system by a multi-spin environment whose elements are coupled to local bosonic baths. Contrarily to the expectation that any non-Markovian effect would be buried by the forgetful mechanism induced by the spin-bath coupling, one can actually induce a full Markovian-to-non-Markovian transition of the two-level system's dynamics, controllable by parameters such as the mismatch between the energy of the two-level system and of the spin environment. For a symmetric coupling, the amount of non-Markovianity surprisingly grows with the number of decoherence channels. DOI: 10.1103/PhysRevA.87.022317
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For the delivery of intensity-modulated radiation therapy (IMRT), highly modulated fields are used to achieve dose conformity across a target tumour volume. Recent in vitro evidence has demonstrated significant alterations in cell survival occurring out-of-field which cannot be accounted for on the basis of scattered dose. The radiobiological effect of area, dose and dose-rate on out-of-field cell survival responses following exposure to intensity-modulated radiation fields is presented in this study. Cell survival was determined by clonogenic assay in human prostate cancer (DU-145) and primary fibroblast (AG0-1522) cells following exposure to different modulated field configurations delivered using a X-Rad 225 kVp x-ray source. Uniform survival responses were compared to in- and out-of-field responses in which 25-99% of the cell population was shielded. Dose delivered to the out-of-field region was varied from 1.6-37.2% of that delivered to the in-field region using different levels of brass shielding. Dose rate effects were determined for 0.2-4 Gy min⁻¹ for uniform and modulated exposures with no effect seen in- or out-of-field. Survival responses showed little dependence on dose rate and area in- and out-of-field with a trend towards increased survival with decreased in-field area. Out-of-field survival responses were shown to scale in proportion to dose delivered to the in-field region and also local dose delivered out-of-field. Mathematical modelling of these findings has shown survival response to be highly dependent on dose delivered in- and out-of-field but not on area or dose rate. These data provide further insight into the radiobiological parameters impacting on cell survival following exposure to modulated irradiation fields highlighting the need for refinement of existing radiobiological models to incorporate non-targeted effects and modulated dose distributions.
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Intrafraction tumour motion is an issue that is of increased interest in the era of image-guided radiotherapy. It is particularly relevant for non-small cell lung cancer, for which a number of recent developments are in use to aid with motion management in the delivery of radical radiotherapy. The ability to deliver hypofractionated ablative doses, such as in stereotactic radiotherapy, has been aided by improvements in the ability to analyse tumour motion and amend treatment delivery. In addition, accounting for tumour motion can enable dose escalation to occur by reducing the normal tissue being irradiated by virtue of a reduction in target volumes. Motion management for lung tumours incorporates five key components: imaging, breath-hold techniques, abdominal compression, respiratory tracking and respiratory gating. These will be described, together with the relevant benefits and associated complexities. Many studies have described improved dosimetric coverage and reduced normal tissue complication probability rates when using motion management techniques. Despite the widespread uptake of many of these techniques, there is a paucity of literature reporting improved outcome in overall survival and local control for patients whenever motion management techniques are used. This overview will review the extent of lung tumour motion, ways in which motion is detected and summarise the key methods used in motion management.
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We test the hypothesis that anesthesia, measured as pain scores, induced by a novel topical anesthetic putty is non-inferior (margin=1.3) to that provided by conventional lidocaine infiltration for the repair of lacerations.