Votes and a half-binomial

AbstractIn two party elections with popular vote ratio pq, 12≤p=1 −q, a theoretical model suggests replacing the so-called MacMahon cube law approximation (pq)3, for the ratio PQ of candidates elected, by the ratio ƒk(p)ƒk(q) of the two half sums in the binomial expansion of (p+q)2k+1 for some k. This ratio is nearly (pq)3 when k = 6. The success probability gk(p)=(pa(pa+qa) for the power law (pq)a≐PQ is shown to so closely approximate ƒk(p)=Σ0k(r2k+1)p2k+1−rqr, if we choose a = ak=(2k+1)!4kk!k!, that 1≤ƒk(p)gk(p)≤1.01884086 for k≥1 if 12≤p≤1. Computationally, we avoid large binomial coefficients in computing ƒk(p) for k>22 by expressing 2ƒk(p)−1 as the sum (p−q) Σ0k(4pq)sas(2s+1), whose terms decrease by the factors (4pq)(1−12s). Setting K = 4k+3, we compute ak for the large k using a continued fraction πak2=K+12(2K+32(2K+52(2K+…))) derived from the ratio of π to the finite Wallis product approximation

The role of the Boudouard and water-gas shift reactions in the methanation of CO or CO2 over Ni/γ-Al2O3 catalyst

The Boudouard and the water-gas shift reactions were studied at different temperatures between 453 and 490 K over a Ni/γ-Al2O3 catalyst in a Carberry batch reactor using various mixtures of CO, H2 and CO2. The activity of the Boudouard reaction was found to be low, compared to the water-gas shift reaction, and diminished over time, suggesting that the temperature was too low for significant activity after an initiation period of CO adsorption. Furthermore, the rate of the Boudouard reaction has been reported to decrease in the presence of H2O and H2. The water-gas shift reaction was found to be the main reaction responsible for the production of CO2 in a mixture of CO, H2 and H2O in the batch reactor. The ratio of the total amount of CO consumed to the total amount of CO2 produced showed that the catalyst was also active towards hydrogenation, where the rate of the hydrogenation reaction was very much faster than the water-gas shift reaction. The resulting ratio of pH2 to pCO was found to be extremely low, probably leading to the production of long-chain hydrocarbons. The stoichiometry of the overall reaction was such that for every mole of mole of CO2 produced, 1.5 mol of CO was consumed in the batch reactor. Kinetic studies were performed in the batch reactor. An Eley-Rideal mechanism was found to provide a good agreement with the experimental results over a wide range of partial pressures of steam and CO

Ordered logit analysis for selectively sampled data

When customers are classified into ordered categories, which are defined from the outset, it may happen that the majority belongs to a single category. If a market researcher is interested in the correlation between the classification and individual characteristics, the natural question is whether one needs to collect data for all customers in that particular category. We address this question for the ordered logit model. We show that there is no need to consider all those customers. All that is required is a simple modification of the log-likelihood, which is based on Bayes' rule. We illustrate our proposed method on simulated data and on data concerning risk profiles of customers of an investment bank

Heat Transport through Rough Channels

We investigate the two-dimensional transport of heat through viscous flow between two parallel rough interfaces with a given fractal geometry. The flow and heat transport equations are solved through direct numerical simulations, and for different conduction-convection conditions. Compared with the behavior of a channel with smooth interfaces, the results for the rough channel at low and moderate values of the Peclet number indicate that the effect of roughness is almost negligible on the efficiency of the heat transport system. This is explained here in terms of the Makarov's theorem, using the notion of active zone in Laplacian transport. At sufficiently high Peclet numbers, where convection becomes the dominant mechanism of heat transport, the role of the interface roughness is to generally increase both the heat flux across the wall as well as the active length of heat exchange, when compared with the smooth channel. Finally, we show that this last behavior is closely related with the presence of recirculation zones in the reentrant regions of the fractal geometry.Comment: 12 pages, 8 figure

The Wisconsin-IIASA Set of Energy/Environment (WISE) Models for Regional Planning and Management: An Overview

This report presents an overview of the analytical framework and quantitative methods used in the IIASA case studies on Regional Energy/Environment Management and Planning. Its purpose is to summarize the structure of the models, to provide a complete listing of the sources of more detailed model and data descriptions, and to indicate how the models are integrated to provide a foundation for regional energy/environment policy maker analysis. The audience for the report includes managers, planners, technical advisors, and modelers. The set of models used in the research project encompasses socioeconomic links to the energy system; energy demand in the residential, industrial, commercial/service, agricultural and transportation sectors; the energy supply sector, environmental impacts associated with the energy system; and policy makers' preferences. The report gives a brief description of the purpose and general structure of each model, data requirements, examples of input and output, and model limitations. As a whole, the models integrate information about energy flows in a region to simulate the energy system and its relationship to other regional variables, e.g., demographic and economic trends and the environment

Experimental support of the scaling rule for demographic stochasticity

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73613/1/j.1461-0248.2006.00903.x.pd

Clinical outcomes and end-of-life treatment in 596 patients with isolated traumatic brain injury:a retrospective comparison of two Dutch level-I trauma centers

Purpose: With an increasingly older population and rise in incidence of traumatic brain injury (TBI), end-of-life decisions have become frequent. This study investigated the rate of withdrawal of life sustaining treatment (WLST) and compared treatment outcomes in patients with isolated TBI in two Dutch level-I trauma centers. Methods: From 2011 to 2016, a retrospective cohort study of patients aged ≥ 18 years with isolated moderate-to-severe TBI (Abbreviated Injury Scale (AIS) head ≥ 3) was conducted at the University Medical Center Rotterdam (UMC-R) and the University Medical Center Utrecht (UMC-U). Demographics, radiologic injury characteristics, clinical outcomes, and functional outcomes at 3–6 months post-discharge were collected. Results: The study population included 596 patients (UMC-R: n = 326; UMC-U: n = 270). There were no statistical differences in age, gender, mechanism of injury, and radiologic parameters between both institutes. UMC-R patients had a higher AIShead (UMC-R: 5 [4–5] vs. UMC-U: 4 [4–5], p &lt; 0.001). There was no difference in the prehospital Glasgow Coma Scale (GCS). However, UMC-R patients had lower GCSs in the Emergency Department and used more prehospital sedation. Total in-hospital mortality was 29% (n = 170), of which 71% (n = 123) occurred after WLST. Two percent (n = 10) remained in unresponsive wakefulness syndrome (UWS) state during follow-up. Discussion: This study demonstrated a high WLST rate among deceased patients with isolated TBI. Demographics and outcomes were similar for both centers even though AIShead was significantly higher in UMC-R patients. Possibly, prehospital sedation might have influenced AIS coding. Few patients persisted in UWS. Further research is needed on WLST patients in a broader spectrum of ethics, culture, and complex medical profiles, as it is a growing practice in modern critical care. Level of evidence: Level III, retrospective cohort study.</p

Kinetic studies of CO2 methanation over a Ni/γ-Al2O3 catalyst using a batch reactor

The methanation of CO2 was investigated over a wide range of partial pressures of products and reactants using a gradientless, spinning-basket reactor operated in batch mode. The rate and selectivity of CO2 methanation, using a 12 wt% Ni/γ–Al2O3 catalyst, were explored at temperatures 453–483 K and pressures up to 20 bar. The rate was found to increase with increasing partial pressures of H2 and CO2 when the partial pressures of these reactants were low; however, the rate of reaction was found to be insensitive to changes in the partial pressures of H2 and CO2 when their partial pressures were high. A convenient method of determining the effect of H2O on the rate of reaction was also developed using the batch reactor and the inhibitory effect of H2O on CO2 methanation was quantified. The kinetic measurements were compared with a mathematical model of the reactor, in which different kinetic expressions were explored. The kinetics of the reaction were found to be consistent with a mechanism in which adsorbed CO2 dissociated to adsorbed CO and O on the surface of the catalyst with the rate-limiting step being the subsequent dissociation of adsorbed CO

Human clade 2.3.4.4 A/H5N6 influenza virus lacks mammalian adaptation markers and does not transmit via the airborne route between ferrets

Since their emergence in 1997, A/H5N1 influenza viruses of the A/goose/ Guangdong/1/96 lineage have diversified in multiple genetic and antigenic clades upon continued circulation in poultry in several countries in Eurasia and Africa. Since 2009, reassortant viruses carrying clade 2.3.4.4 hemagglutinin (HA) and internal and neuraminidase (NA) genes of influenza A viruses of different avian origin have been detected, yielding various HA-NA combinations, such as A/H5N1, A/H5N2, A/H5N3, A/H5N5, A/H5N6, and A/H5N8. Previous studies reported on the low pathogenicity and lack of airborne transmission of A/H5N2 and A/H5N8 viruses in the ferret model. However, although A/H5N6 viruses are the only clade 2.3.4.4 viruses that crossed the species barrier and infected humans, the risk they pose for human health remains poorly characterized. Here, the characterization of A/H5N6 A/Guangzhou/39715/2014 virus in vitro and in ferrets is described. This A/H5N6 virus possessed high polymerase activity, mediated by the E627K substitution in the PB2 protein, which corresponds to only one biological trait out of the three that were previously shown to confer airborne transmissibility to A/H5N1 viruses between ferrets. This might explain its lack of airborne transmission between ferrets. After intranasal inoculation, A/H5N6 virus replicated to high titers in the respiratory tracts of ferrets and was excreted for at least 6 days. Moreover, A/H5N6 virus caused severe pneumonia in ferrets upon intratracheal inoculation. Thus, A/H5N6 virus causes a more severe disease in ferrets than previously investigated clade 2.3.4.4 viruses, but our results demonstrate that the risk from airborne spread is currently low

Species abundance distributions: moving beyond single prediction theories to integration within an ecological framework

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75247/1/j.1461-0248.2007.01094.x.pd