How robust is a thermal photon interpretation of the ALICE low-p_T data?

We present a rigorous theoretical analysis of the ALICE measurement of low-p_T direct-photon production in central lead-lead collisions at the LHC with a centre-of-mass energy of \sqrt{s_{NN}}=2.76 TeV. Using NLO QCD, we compute the relative contributions to prompt-photon production from different initial and final states and the theoretical uncertainties coming from independent variations of the renormalisation and factorisation scales, the nuclear parton densities and the fragmentation functions. Based on different fits to the unsubtracted and prompt-photon subtracted ALICE data, we consistently find T = 304 \pm 58 MeV and 309 \pm 64 MeV for the effective temperature of the quark-gluon plasma (or hot medium) at p_T \in [0.8;2.2] GeV and p_T \in [1.5;3.5] GeV as well as a power-law (p_T^{-4}) behavior for p_T > 4 GeV as predicted by QCD hard scattering.Comment: 18 pages, 7 figures, 1 tabl

An Extented Sensitivity Analysis in Linear Programming Problems

When a real world problem is formulated as a linear programming model, we are often faced with difficulties in the parameter specification. We might know the plausible values or the possible ranges of parameters, but there still remains uncertainty. The parameter values could be obtained more exactly by experiments, investigations and/or inspections. However, to make such an experiment, investigation or inspection, expenses would be necessary. Because of capital limitations, we cannot invest in all possible experiments, investigations and inspections. Thus, we have a selection problem, which uncertainty reduction is the most profitable. In this paper, we discuss an analytic approach to the problem. Because of the difficulty of the global analysis, we make a local analysis around appropriate values of parameters. We focus on giving the decision maker useful information for the selection. First, sensitivity analyses with respect to the uncertain parameters are developed. The sensitivities are available only for the marginal domain without changing the optimal basis. The domain is obtained as an interval. The difficulty of the sensitivity analysis is in the cases of degeneracy and multiplicity of the optimal solutions. A treatment of such difficult cases is proposed. Finally, a numerical example is given for illustrating the proposed approach

Group classification of the Sachs equations for a radiating axisymmetric, non-rotating, vacuum space-time

We carry out a Lie group analysis of the Sachs equations for a time-dependent axisymmetric non-rotating space-time in which the Ricci tensor vanishes. These equations, which are the first two members of the set of Newman-Penrose equations, define the characteristic initial-value problem for the space-time. We find a particular form for the initial data such that these equations admit a Lie symmetry, and so defines a geometrically special class of such spacetimes. These should additionally be of particular physical interest because of this special geometric feature.Comment: 18 Pages. Submitted to Classical and Quantum Gravit

The RESET Mindset Model applied on decreasing antibiotic usage in dairy cattle in the Netherlands

This article analyses sanctuary initiatives intended to change the situation of ‘irregularised residents’. Through fieldwork, three main activities are identified: assistance for welfare services, alternatives to inaccessible services, and inventing new ways of organising togetherness in the city. The role of activists in the initiatives links to discussions within Critical Human Rights literature, which emphasise the anti-institutionalist origins of rights. Yet, a complex interplay also plays out through co-current resistance against the state’s migration policing and collaboration with city-level state agencies. Understanding this complex process is important to improving knowledge of both the politics of sanctuary and human rights

Mid-IR continuous-wave fiber-laser-pumped optical parametric oscillators

We review recent developments in continuous-wave mid-infrared optical parametric oscillators pumped by fiber lasers. Such devices are potentially valuable spectroscopic sources providing high output powers and rapid, wide-range tuning in the mid-infrared molecular fingerprint region

Colophospermum mopane Wood Utilisation in the Northeast of the Limpopo Province, South Africa

The use of Colophospermum mopane wood was quantified from six villages in the northeast of the Limpopo Province, South Africa. One hundred and eighty individuals were interviewed from the selected villages. Three villages were located in the depleted woodlands and the remaining three at abundant woodlands. Traditional governance structures within the selected villages and relevant conservation department officials were also interviewed. Colophospermum mopane is an essential source of fuelwood and provide poles used for construction of traditional structures. Each family uses 6.8 ± 0.1 kg of Colophospermum mopane fuelwood for cooking day-1 in the woodland depleted villages, while 8.2 ± 0.2 kg is used at the woodland abundant villages. Colophospermum mopane is preferred for construction of traditional structures because its wood is durable and is able to resists the effects of termites and wood borers

Fostering Research Integrity through Institutional Policies: The Case of a Selected Institution of Higher Education1

Truth, trust and integrity are essential to research at higher education institutions. These institutions have accordingly adopted several policies tofoster research integrity. This article explores the likelihood that relevant policies at a selected institution of higher education foster research integrity. The qualitative, single exploratory case study commences with a review of scholarly literature and results in a conceptual model used for a directed content analysis of relevant institutional policies. The findings indicate that these policies do complement each other in fostering research integrity. Further research will be necessary to establish whether policies indeed contribute to responsible researcher conduct