Alien Registration- Roy, Donat F. (Greenville, Piscataquis County)

https://digitalmaine.com/alien_docs/8552/thumbnail.jp

Simulations of the last interglacial and the subsequent glacial inception with the Planet Simulator

International audienceThe Planet Simulator was used to perform equilibrium simulations of the Eemian interglacial at 125 kyBP and the glacial inception at 115 kyBP. Additionally, an accelerated transient simulation of that interval was performed. During this period the changes of Earth's orbital parameters led to a reduction of summer insolation in the northern latitudes. The model has been run in different configurations in order to evaluate the influence of the individual sub-models. The strongest reaction on the insolation change was observed when the atmosphere was coupled with all available sub-systems: a mixed-layer ocean and a sea-ice model as well as a vegetation model. In the simulations representing the interglacial, the near-surface temperature in northern latitudes is higher compared to the preindustrial reference run and almost no perennial snow cover occurs. In the run for the glacial inception, wide areas in mid and high northern latitudes show negative temperature anomalies and wide areas are covered by snow or ice. The transient simulation shows that snow volume starts to increase after summer insolation has fallen below a critical value. The main reason for the beginning glaciation is the locally reduced (summer) temperature as a consequence of reduced summer insolation. Therefore, a larger fraction of precipitation falls as snow and less snow can melt. That mechanism is amplified by the snow-albedo-feedback

Semi-parametric bivariate polychotomous ordinal regression

A pair of polychotomous random variables (Y1,Y2)⊤=:YY(Y1,Y2)⊤=:YY, where each YjYj has a totally ordered support, is studied within a penalized generalized linear model framework. We deal with a triangular generating process for YYYY, a structure that has been employed in the literature to control for the presence of residual confounding. Differently from previous works, however, the proposed model allows for a semi-parametric estimation of the covariate-response relationships. In this way, the risk of model mis-specification stemming from the imposition of fixed-order polynomial functional forms is also reduced. The proposed estimation methods and related inferential results are finally applied to study the effect of education on alcohol consumption among young adults in the UK

Kinetics of oxygen uncoupling of a copper based oxygen carrier

Here, an oxygen carrier consisting of 60 wt% CuO supported on a mixture of Al_2O_ 3 and CaO (23 wt% and 17 wt% respectively) was synthesised by wet-mixing powdered CuO, Al(OH)_3 and Ca(OH)_2, followed by calcination at 1000⁰C. Its suitability for chemical looping with oxygen uncoupling (CLOU) was investigated. After 25 repeated redox cycles in either a thermogravimetric analyser (TGA) or a laboratory-scale fluidised bed, (with 5 vol% H_2 in N_2 as the fuel, and air as the oxidant) no significant change in either the oxygen uncoupling capacity or the overall oxygen availability of the carrier was found. In the TGA, it was found that the rate of oxygen release from the material was controlled by intrinsic chemical kinetics and external transfer of mass from the surface of the particles to the bulk gas. By modelling the various resistances, values of the rate constant for the decomposition were obtained. The activation energy of the reaction was found to be 59.7 kJ/mol (with a standard error of 5.6 kJ/mol) and the corresponding pre-exponential factor was 632 m^3/mol/s. The local rate of conversion within a particle was assumed to occur either (i) by homogeneous chemical reaction, or (ii) in uniform, non-porous grains, each reacting as a kinetically-controlled shrinking core. Upon cross validation against a batch fluidised bed experiment, the homogeneous reaction mode l was found to be more plausible. By accurately accounting for the various artefacts (e.g. mass transfer resistances) present in both TGA and Fluidised bed experiments, it was possible to extract a consistent set of kinetic parameters which reproduced the rates of oxygen release in both experiments.This work is supported by the Engineering and Physical Sciences Research Council (EPSRC grant EP/I010912/1) and The Cambridge Commonwealth, European & International Trust as well as Selwyn College, University of Cambridge. The authors would also like to thank Mohammad Ismail for the XRD analysis and Zlatko Saracevic for the nitrogen adsorption analysis.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.apenergy.2015.10.00

Discrete responses in penalized Generalized Linear Models

Generalized Linear Models (GLMs) are an important class of models that provide a unifying framework for the analysis and estimation of several types response variables, including discrete outcomes. This thesis discusses the representation, estimation and some inferential results of various models for categorical responses within a penalized GLM structure. In particular, a ridge-type penalty form is included to enforce certain properties of the functional form of the covariate-response relationship. Specifically, fully, non-parametric effects as well as smoothed spatial dependencies are shown to be all be represented through an appropriate combination of linear predictors and penalisation terms. The emphasis of the thesis is on bivariate models for discrete responses that are commonly employed in cross-sectional studies to correct for the presence of direct unmeasured confounding and/or non-random sample selection issues. The former refers to a situation where both the response of interest and one of its relevant covariate are affected by a third variable, the confounder, which is either unobserved or not readily quantifiable by the researcher. The latter, instead, accounts for those instances where item non-response does not occur at random, but is driven by some underlying factors. In either case, not controlling for pertinent confounders may lead to detrimental effects in the estimates obtained, and standard estimators are usually inconsistent. Under certain conditions, bivariate models are proven to mend these issues. The thesis shows how both types of models can be represented within a unified penalized GLM framework for discrete responses. Methodological advances are then provided towards two main research avenues: (i) the estimation of non-parametric covariate effects and smoothed spatial dependencies, and (ii) an improved flexibility achieved through the specification of copula functions for the idiosyncratic model components. In this way, several alternative dependence structures among the responses are also introduced. The extensive use of real datasets illustrates each situation in details and completes the analysis

Use of a Chemical-Looping Reaction to Determine the Residence Time Distribution of Solids in a Circulating Fluidized Bed

The residence time distribution (RTD) of solids in various sections of a circulating fluidized bed (CFB) is of great importance for design and operation but is often difficult to determine experimentally. A noninvasive method is described, for which the RTD was derived from temporal measurements of the temperature following the initiation of a chemical-looping reaction. To demonstrate the method, a CuO-based oxygen carrier was used in a small-scale CFB, and measurements were made in the fuel reactor, operated as a bubbling fluidized bed. The measurements were fitted to the tanks-in-series model, modified to account for heat losses from the reactor. There was excellent agreement between the model and the experiment. Limitations and further improvements of the method are discussed, also with respect to larger reactors.This work is supported by the Engineering and Physical Sciences Research Council (EPSRC Grant EP/I010912/1).This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1002/ente.20160014

Digital accessible knowledge: Mobilizing legacy data and the future of taxonomic publishing

No abstract available

The effect of different particle residence time distributions on the chemical looping combustion process

A model for chemical looping combustion has been developed to allow the effect of different residence time distributions of oxygen carrier particles in the air and fuel reactors to be investigated. The model envisages two, coupled fluidised bed reactors with steady circulation of particles between them. The results show that the process is sensitive to the residence time distributions, particularly when the mean residence time of particles in the reactors is similar to the time required for them to react completely. Under certain operating conditions, decreasing the variance of the residence time distribution, leads to a greater mean conversion of the particles by the time they leave the reactors and higher mean rates of reaction in the beds. In this way the required inventory and circulation rate of solids could be reduced, which would lower the capital and operating costs of a CLC process. Since the residence time distribution of solids is important, it should be taken into account when modelling or designing a chemical looping combustion process, e.g. by using a tanks-in-series model. This work indicates that if the number of tanks, N ≤ 5, knowing N to the nearest integer is generally sufficient, unless a high degree of accuracy is needed. As N increases, the sensitivity of the coupled system decreases, so for N > 5, knowing the value to the nearest 5 or 10 tanks is sufficient. This is valid whether N is the same or different in the two reactors. Chemical looping combustion is one example of a reactor-regenerator system, so the results are also relevant for other processes of this type, such as fluidised catalytic cracking

Resultados en la cirugía de revisión de la artroplastia de rodilla con aporte de aloinjerto óseo

Hemos realizado un estudio retrospectivo de 12 pacientes (13 rodillas) intervenidos entre 1975 y 2001 de revisión de prótesis de rodilla utilizando aloinjerto óseo, valorando el resultado funcional y clínico. La edad media fue de 62 años. La indicación primaria fue de gonartrosis primaria en 8 casos (9 rodillas), artrosis postraumática en 1 caso y 2 casos de artritis reumatoide. Los defectos óseos fueron clasificados utilizando la clasificación del Anderson Orthopedic Institute Research. Se utilizó aloinjerto de forma fragmentada en 11 casos y de forma estructural en 2. El seguimiento medio fue de 69 meses. En la valoración clínica se utilizó la escala de la Knee Society; la evaluación radiográfica evaluó la existencia de integración del injerto en el huésped. Los 2 casos de artritis reumatoide presentaron infección profunda protésica y que necesitaron de una artrodesis como solución definitiva. El resto de pacientes mostró unos resultados satisfactorios con buena integración del injerto al huésped. La utilización de aloinjerto fragmentado y estructural en la cirugía de revisión protésica de rodilla resuelve de manera satisfactoria la presencia del defecto óseo, aunque en enfermos con algú tipo de inmunopresión, el elevado riesgo de infección profunda en cirugía de revisión nos obliga a extremar las precauciones.We have carried out a retrospective study of 12 patients (13 knees) treated between 1975 and 2001 after failed total knee arthroplasty (TKA), by means of revision surgery using bone allograft. The mean age was of 62 years. The primary indication was degenerative osteoarthritis in 8 cases (9 knees), postraumatic osteoarthritis in 1 case and rheumatoid artritis in 2 cases. The bony defects were classified according to the Anderson's Orthopedic Institute classification. Fragmented allograft was used in 11 cases and structural allograft in 2. The mean follow-up time was of 69 months. Outcome was evaluated through functional and clinical result. For the clinical evaluation the scale of the Knee Society was used; the radiographic evaluation assessed the degree of integration of the graft. The 2 cases of rheumatoid artritis presented deep infection of the TKA that required an arthrodesis for definitive solution. The rest of patients showed satisfactory results with good integration of the bone graft. The use of fragmented and structural allograft in revision surgery of failed TKA solves in a satisfactory way the presence of bony defects, although in patients with some degree of inmunosupression the high risk of deep infection forces to extreme the cautions

Genetic analyses of celiac disease in a Spanish population confirm association with CELIAC3 but not with CELIAC4

[EN] Genetic predisposition to celiac disease (CD) is determined primarily by the human leukocyte antigen (HLA) genes (CELIAC1 region; 6p21), although many loci are involved in disease susceptibility. First, we have analysed a large series of CD patients from the Spanish Mediterranean region who had previously been characterised for the HLA complex. We have investigated how relevant regions contribute to CD susceptibility: CELIAC3 (CD28/CTLA4/ICOS region on 2q33) and CELIAC4 (19p13) as well as the tumour necrosis factor alpha (TNF-alpha) and the linfotoxin loci by case-control and association analyses. We highlight the association with the +49*A allele of cytotoxic T-lymphocyte-associated antigen 4 locus (P = 0.01), and the -308*A of TNF-alpha locus (P = 0.0008) in DQ2 individuals, although an independent role for TNF-alpha as risk factor has not been proven. Moreover, we do not confirm the association with the CELIAC4 region polymorphisms described in other populations.We are grateful for the kind collaboration of patients and families and Asociación de Celíacos de la Comunidad Valenciana (ACECOVA). This work was supported by the Fondo de Investigacio¿n Sanitaria (grant PI02573) and by the CSIC Intramural Frontiers Project (PROFICEL). ED holds a fellowship from the Fundacio¿n La Fe. English text revised by F. BarracloughCapilla, A.; Donat, E.; Planelles, D.; Espinós-Armero, CÁ.; Ribes-Koninckx, C.; Palau, F. (2007). Genetic analyses of celiac disease in a Spanish population confirm association with CELIAC3 but not with CELIAC4. Tissue Antigens. 70(4):324-329. https://doi.org/10.1111/j.1399-0039.2007.00899.x32432970