Estimability and efficiency in nearly orthogonal 2[m1] x 3[m2] deletion designs

This article considers single replicate factorial experiments in incomplete blocks. A single replicate 2^m1 x 3^m2 deletion design in 3 incomplete blocks is obtained from a single replicate 3^m, where m = m_1 + m_2, preliminary design by deleting all runs (or treatment combinations) with the first m_1 factors at the level two. A systematic method for determining the unbiasedly estimable (u.e.) and not unbiasedly estimable (n.u.e.) factorial effects is provided. It is shown that for m_2 > 0 all factorial effects of the type F( α_1 · · · α_m_1 , α_(m_1 +1) · · · α_m), where α_i; = 0, l for i = 1, · · ·, m_1, α_i; = 0, 1, 2 for i = m_(1+1), · · ·, m, with (α_1 · · · α_m) != (0 · · · 0), and (α_m,+l · · · _m) != α(l · · · 1) for a= 1, 2, are u.e. and the remaining factorial effects are n.u.e. It is noted that (2^m_1 - 1) factorial effects of 2^m_1 factorial experiments and (3^m_2) factorial effects of 3^m, factorial experiments, which are embedded in 2^m_1 x 3^m, factorial experiments, are u. e. The 2 x 3m-l deletion designs were considered in the work of Voss (1986). Defining factorial effects of a 2^m_1 x 3^m, factorial experiment in a form different than in Voss (1986), we develop a simple representation of u.e. and n. u. e. factorial effects. In this representation, there are (2^(m_1 + 1) + 1) n. u. e. factorial effects of the type F( α_1 · · · α_m_1, α· · · α). This number is smaller than the corresponding number of n. u. e. factorial effects in the representation of Voss (1986). The relative efficiency expressions, and their bounds, in the estimation of factorial effects of 2^m_1 x 3^m_2 deletion designs are also given

Planning for Excellence: Insights from an International Review of Regulators’ Strategic Plans

What constitutes regulatory excellence? Answering this question is an indispensable first step for any public regulatory agency that is measuring, striving towards, and, ultimately, achieving excellence. One useful way to answer this question would be to draw on the broader literature on regulatory design, enforcement, and management. But, perhaps a more authentic way would be to look at how regulators themselves define excellence. However, we actually know remarkably little about how the regulatory officials who are immersed in the task of regulation conceive of their own success. In this Article, we investigate regulators’ definitions of regulatory excellence by drawing on a unique source of data that provides an important window on regulators’ own aspirations: their strategic plans. Strategic plans have been required or voluntarily undertaken for the past decade or longer by regulators around the globe. In these plans, regulators offer mission statements, strategic goals, and measurable and achievable outcomes, all of which indicate what regulators value and are striving to become. Occasionally, they even state explicitly where they have fallen short of “best-in-class” status and how they intend to improve. To date, a voluminous literature exists examining agency practices in strategic planning, but we are aware of no study that tries to glean from the substance of a sizeable number of plans how regulators themselves construe regulatory excellence. The main task of this Article is undertaking this effort. This Article draws on twenty plans from different regulators in nine countries. We found most generally that excellent regulators describe themselves (though not necessarily using exactly these words) as institutions that are more (1) efficient, (2) educative, (3) multiplicative, (4) proportional, (5) vital, (6) just, and (7) honest. In addition to these seven shared attribute categories, our reading of the plans also revealed five other “unusual” attributes that only one or two agencies mentioned. Beyond merely cataloguing the attributes identified by agencies, this Article also discusses commonalities (and differences) between plan structures, emphases, and framings. We found that the plans differed widely in features such as the specificity of their mission statements, the extent to which they emphasized actions over outcomes (or vice versa), and the extent to which commitments were organized along organizational fiefdoms or cut across bureaucratic lines. We urge future scholarship to explore alternative methods of text mining, and to study strategic plans over time within agencies, in order to track how agencies’ notions of regulatory excellence respond to changes in the regulatory context and the larger circumstances within which agencies operate. Looking longitudinally will also shed light on how agencies handle strategic goals that are either met or that prove to be unattainable

Tidal Destruction of The First Dark Microhalos

We point out that the usual self-similarity in cold dark matter models is broken by encounters with individual normal galactic stars on sub-pc scale. Tidal heating and stripping must have redefined the density and velocity structures of the population of the Earth-mass dark matter halos, which are likely to have been the first bound structures to form in the Universe. The disruption rate depends strongly on {\it galaxy types} and the orbital distribution of the microhalos; in the Milky Way, stochastic radial orbits are destroyed first by stars in the triaxial bulge, microhalos on non-planar retrograde orbits with large pericenters and/or apocenters survive the longest. The final microhalo distribution in the {\it solar neighborhood} is better described as a superposition of filamentry microstreams rather than as a set of discrete spherical clumps in an otherwise homogeneous medium. We discuss its important consequences to our detections of microhalos by direct recoil signal and indirect annihilation signal.Comment: 13 pages, 3 figures, Astrophysical Journal, accepte

Numerical comparison of pipe-column-separation models

Results comparing six column-separation numerical models for simulating localized vapor cavities and distributed vaporous cavitation in pipelines are presented. The discrete vapor-cavity model (DVCM) is shown to be quite sensitive to selected input parameters. For short pipeline systems, the maximum pressure rise following column separation can vary markedly for small changes in wave speed, friction factor, diameter, initial velocity, length of pipe, or pipe slope. Of the six numerical models, three perform consistently over a broad number of reaches. One of them, the discrete gas-cavity model, is recommended for general use as it is least sensitive to input parameters or to the selected discretization of the pipeline. Three models provide inconsistent estimates of the maximum pressure rise as the number of reaches is increased; however, these models do give consistent results provided the ratio of maximum cavity size to reach volume is kept below 10%.Angus R. Simpson and Anton Bergan

Vieillissement et coûts des soins de santé : y a-t-il un problème?

Cet article traite des perspectives futures des dépenses au titre des soins de santé, en essayant d’en dégager les pressions prévisibles sur le régime de prestation des soins de santé, particulièrement celles attribuables au vieillissement de la population du Canada. Il en ressort que le phénomène du vieillissement, exprimé en coûts globaux des soins de santé, ne sera pas nécessairement un problème majeur. Les hausses de coûts prévues pour les services de santé doivent être mises en relation avec l’évolution de la capacité de production de l’économie canadienne. L’article examine également les implications que cela suppose pour la planification des soins de santé.This paper discusses various projections of health-care expenditures in terms of foreseeable pressures on the health-care system due to the aging of the Canadian population. The conclusion is that the impact of aging on health-care costs will not necessarily be a major problem. Projected cost increases have to be related to the evolution of the nation's productive capacity. The article also examines some implications in terms of health-care planning.El presente artículo trata de las perspectivas futuras de los gastos relativos a los cuidados de la salud, intentando prever las presiones posibles sobre el régimen de prestación con respecto a los cuidados de la salud y sobre todo aquellas atribuidas al envejecimiento de la población de Canadá. Se puede decir que los costos globales de los cuidados de la salud ligados al fenómeno del envejecimiento no será necesariamente un problema major. Los aumentos de costos previstos para los servicios de atención a la salud deberan estar en relación con la evolución de la capacidad productiva de la economía canadiense. Este artículo examina igualmente las implicaciones que ello supone para la planificacíon de los cuidados de la salud

Plasticity in transmission strategies of the malaria parasite, Plasmodium chabaudi : environmental and genetic effects

Parasites may alter their behaviour to cope with changes in the within-host environment. In particular, investment in transmission may alter in response to the availability of parasite resources or host immune responses. However, experimental and theoretical studies have drawn conflicting conclusions regarding parasites' optimal (adaptive) responses to deterioration in habitat quality. We analyse data from acute infections with six genotypes of the rodent malaria species to quantify how investment in transmission (gametocytes) is influenced by the within-host environment. Using a minimum of modelling assumptions, we find that proportional investment in gametocytogenesis increases sharply with host anaemia and also increases at low parasite densities. Further, stronger dependence of investment on parasite density is associated with greater virulence of the parasite genotype. Our study provides a robust quantitative framework for studying parasites' responses to the host environment and whether these responses are adaptive, which is crucial for predicting the short-term and evolutionary impact of transmission-blocking treatments for parasitic diseases

Motivations for image publishing and tagging on Flickr

Changes in photographic and internet technology have revolutionised the way people create, process and share digital images. This paper investigates people's motivations for image publishing and tagging on the web 2.0 site Flickr. Using an online pilot survey, 33 participants answered questions about their uploading and tagging practices, and whether or not they hope to make a commercial gain from their images. The results show that most people have two main motivational reasons both for using Flickr, and for the tagging of their images. However, whilst a person may be motivated to use Flickr for both personal and social reasons, tagging motivation tends to focus more exclusively on either one or the other of these two factors. Overall it was found that social organisation and social communication are the most popular motivational factors for both using Flickr and for tagging images, suggesting that Flickr is enjoyed for the community environment it provides rather than as a place to store images. However despite people's desire to share their images, most users are not hoping to make a commercial gain from the items they upload.Published versio

On the Proof of Dark Matter, the Law of Gravity and the Mass of Neutrinos

We develop a new method to predict the density associated with weak lensing maps of (un)relaxed clusters in a range of theories interpolating between GR and MOND (General Relativity and Modified Newtonian Dynamics). We apply it to fit the lensing map of the bullet merging cluster 1E0657-56, in order to constrain more robustly the nature and amount of collisionless matter in clusters {\it beyond} the usual assumption of spherical equilibrium (Pointecouteau & Silk 2005) and the validity of GR on cluster scales (Clowe et al. 2006). Strengthening the proposal of previous authors we show that the bullet cluster is dominated by a collisionless -- most probably non-baryonic -- component in GR as well as in MOND, a result consistent with the dynamics of many X-ray clusters. Our findings add to the number of known pathologies for a purely baryonic MOND, including its inability to fit the latest data from the Wilkinson Microwave Anisotropy Probe. A plausible resolution of all these issues and standard issues of Cold Dark Matter with galaxy rotation curves is the "marriage" of MOND with ordinary hot neutrinos of 2eV. This prediction is just within the GR-independent maximum of neutrino mass from current $\beta$-decay experiments, and is falsifiable by the Karlsruhe Tritium Neutrino (KATRIN) experiment by 2009. Issues of consistency with strong lensing arcs and the large relative velocity of the two clusters comprising the bullet cluster are also addressed.Comment: 4 pages, 1 figure, accepted for publication in ApJL. Added a simple model of the bullet cluster's high velocity in TeVeS, and discussions of sterile neutrinos and of non-uniqueness of the lensing deprojectio

Early weight loss in parkinsonism predicts poor outcomes : evidence from an incident cohort study

This study was funded by Parkinson’s UK, the Scottish Chief Scientist Office, NHS Grampian endowments, the BMA Doris Hillier award, RS Macdonald Trust, the BUPA Foundation, and the Special Parkinson’s Research Interest Group (SPRING). The Article Processing Charge was funded by Parkinson's UK.Peer reviewedPublisher PD