Using imprecise continuous time Markov chains for assessing the reliability of power networks with common cause failure and non-immediate repair.

We explore how imprecise continuous time Markov chains can improve traditional reliability models based on precise continuous time Markov chains. Specifically, we analyse the reliability of power networks under very weak statistical assumptions, explicitly accounting for non-stationary failure and repair rates and the limited accuracy by which common cause failure rates can be estimated. Bounds on typical quantities of interest are derived, namely the expected time spent in system failure state, as well as the expected number of transitions to that state. A worked numerical example demonstrates the theoretical techniques described. Interestingly, the number of iterations required for convergence is observed to be much lower than current theoretical bounds

Restriction on the energy and luminosity of e+e- storage rings due to beamstrahlung

The role of beamstrahlung in high-energy e+e- storage-ring colliders (SRCs) is examined. Particle loss due to the emission of single energetic beamstrahlung photons is shown to impose a fundamental limit on SRC luminosities at energies 2E_0 >~ 140 GeV for head-on collisions and 2E_0 >~ 40 GeV for crab-waist collisions. With beamstrahlung taken into account, we explore the viability of SRCs in the E_0=240-500 GeV range, which is of interest in the precision study of the Higgs boson. At 2E_0=240 GeV, SRCs are found to be competitive with linear colliders; however, at 2E_0=400-500 GeV, the attainable SRC luminosity would be a factor 15-25 smaller than desired.Comment: Latex, 5 pages. v2 differs only by minor changes is abstract and introduction, one reference is added. v3 corresponds to the paper published in PR

A robust Bayesian analysis of the impact of policy decisions on crop rotations.

We analyse the impact of a policy decision on crop rotations, using the imprecise land use model that was developed by the authors in earlier work. A specific challenge in crop rotation models is that farmer’s crop choices are driven by both policy changes and external non-stationary factors, such as rainfall, temperature and agricultural input and output prices. Such dynamics can be modelled by a non-stationary stochastic process, where crop transition probabilities are multinomial logistic functions of such external factors. We use a robust Bayesian approach to estimate the parameters of our model, and validate it by comparing the model response with a non-parametric estimate, as well as by cross validation. Finally, we use the resulting predictions to solve a hypothetical yet realistic policy problem

Three Years in a Mad-House: The Story of my Life at the Asylum, my Escape, and the Strange Adventures which Followed

https://digitalcommons.library.tmc.edu/ebooks/1007/thumbnail.jp

Collection Conditions and Self-Rated Health: An Analysis of European Data,

Self-rated health is only a biased reflection of real health. However, it is difficult to isolate and assess this bias. In particular, to what extent does the information collected depended on the collection conditions, given that these vary considerably between countries and surveys? The resources in the Share database enable us to analyse two collection method effects: the position of the subjective health question in the questionnaire and the wording of the suggested response modalities. Both effects have an impact: the average level of health, the distribution of states of health and links between health and other variables are altered when the collection conditions change. The positioning effect is homogenous within all countries. The wording of the suggested response modalities also changes the measure of self-rated health. For example, Sweden appears to be the healthiest country using the initial wording, but moves down to fifth place using a second wording.Self-Reported Health, Framing Effects, International Health Rankings

Conditions de collecte et santé subjective : analyse sur données européennes

It is fairly banal to say that subjective health, the most widely-used health variable, is measured with error. In particular, it would seem important to know how subjective health information depends on the way in which it is collected, as this latter varies widely between countries and surveys. In this article we use a quasi-experimental feature in the SHARE questionnaire to evaluate two framing effects: the place of the health question in the questionnaire, and the verbal labels associated with the different possible answers (on a one to five scale). The place effect is particularly homogeneous: in all of the countries, individuals declare better health after having replied to a detailed health questionnaire. We also find that functional health variables mobility and social and sensory limits to daily life play a more important role in determining health when the health question appeared after the detailed health questionnaire. The effect of different verbal labels is strong and less homogeneous than the place effect: it varies widely, in particular, between countries.subjective health ; framing effects ; response bias ; cross-country ranking

Strong gametocytocidal effect of methylene blue-based combination therapy against falciparum malaria

With the availability of new preventive and curative interventions, global malaria control has been strengthened significantly in recent years. Drugs effective in reducing malaria gametocytaemia might contribute to local elimination and possible long-term eradication. We here report on the effects of methylene blue (MB)-based malaria combination therapy on gametocytaemia during a randomised-controlled trial in Burkina Faso. An open-label randomised controlled phase II study in 180 children aged 6-10 years with uncomplicated falciparum malaria was conducted in Nouna, north-western Burkina Faso. Children were randomised to MB-artesunate (AS), MB-amodiaquine (AQ), and AS-AQ (local standard of care). Overall follow-up was for 28 days, follow-up for gametocytaemia was for 14 days. The treatment groups were similar in baseline characteristics and there was only one loss to follow-up. Compared to AS-AQ, both MB-containing regimens were associated with significantly reduced gametocyte carrier rates during follow-up days 3, 7, and 14. This effect was seen both in patients with and without P. falciparum gametocytaemia at baseline. MB reveals pronounced gametocytocidal activity which appears to act against both existing and developing P. falciparum gametocytes. MB-based combination therapy thus has the potential to reduce transmission of P. falciparum malaria in endemic regions, which has important implications for future elimination and eradication strategies