Multiscale time series modelling with an application to the relativistic electron intensity at the geosynchronous orbit

In this paper, a Bayesian system identification approach to multiscale time series modelling is proposed, where multiscale means that the output of the system is observed at one(coarse) resolution while the input of the system is observed at another (One) resolution. The proposed method identifies linear models at different levels of resolution where the link between the two resolutions is realised via non-overlapping averaging process. This averaged time series at the coarse level of resolution is assumed to be a set of observations from an implied process so that the implied process and the output of the system result in an errors-in-variables ARMAX model at the coarse level of resolution. By using a Bayesian inference and Markov Chain Monte Carlo (MCMC) method, such a modelling framework results in different dynamical models at different levels of resolution at the same time. The new method is also shown to have the ability to combine information across different levels of resolution. An application to the analysis of the relativistic electron intensity at the geosynchronous orbit is used to illustrate the new method

Biophysical modelling of a drosophila photoreceptor

It remains unclear how visual information is co-processed by different layers of neurons in the retina. In particular, relatively little is known how retina translates vast environmental light changes into neural responses of limited range. We began examining this question in a bottom-up way in a relatively simple °y eye. To gain understanding of how complex bio-molecular interactions govern the conversion of light input into voltage output (phototransduction), we are building a biophysical model of the Drosophila R1-R6 photoreceptor. Our model, which relates molecular dynamics of the underlying biochemical reactions to external light input, attempts to capture the molecular dynamics of phototransduction gain control in a quantitative way

New York City Goes to College: A First Look at Patterns of College Enrollment, Persistence, and Degree Attainment for NYC High School Students

Over the past 15 years, in New York City and across the country, expectations for high schools -- and high school students -- have changed dramatically. Increasingly, high schools are being asked not only to reduce dropout rates and boost graduation rates, but also to impart knowledge, skills, and experiences that will prepare students to succeed in college. Similarly, many post-secondary institutions are also under increased pressure, as policymakers and the public ask hard questions about low college completion rates. Public K-12 and post-secondary systems in many cities, including NYC, have started working together in largely unprecedented ways, attempting to create a more seamless and effective education "pipeline."To inform these efforts, it is essential to know more about students' pathways into and through college. The Research Alliance has developed a unique dataset that tracks multiple cohorts of NYC students from 9thgrade through college. To do so, we combined high-school level data about NYC public school students with information from the National Student Clearinghouse. This briefsummarizes findings from the initial analyses conducted with this important new dataset. It describes recent patterns of college enrollment, persistence, and completion for NYC students, and begins to explore factors that may affect their college outcomes

Relaciones filogenéticas y distribución de los Rhizotrogini (Coleoptera, Scarabaeidae, Melolonthinae) en el Mediterráneo occidental

In this paper, the West Mediterranean genera of Rhizotrogini are reviewed. Two kinds of character sets are discussed: those relative to the external morphology of the adult and those of the male and female genitalia. Genera Amadotrogus Reitter, 1902; Amphimallina Reitter, 1905; Amphimallon Berthold, 1827; Geotrogus Guérin-Méneville, 1842; Monotropus Erichson, 1847; Pseudoapeterogyna Escalera, 1914 and Rhizotrogus Berthold, 1827 are analysed: to demonstrate the monophyly of this group of genera; to asses the realtionships of these taxa; to test species transferred from Rhizotrogus to Geotrogus and Monotropus, and to describe external morphological and male and female genitalic characters which distinguish each genus. Phylogenetic analysis leads to the conclusion that this group of genera is monophyletic. However, nothing can be said about internal relationships of the genera, which remain in a basal polytomy. Some of the species tranferred from Rhizotrogus are considered to be a new genus Firminus. The genera Amphimallina and Pseudoapterogyna are synonymized with Amphimallon and Geotrogus respectively.En este trabajo se revisan los géneros de Rhizotrogini del Mediterraneo Occidental. Dos clases de caracteres son estudiados; los correspondientes a la morfología externa de los adultos y a las genitalias femenina y masculina. Se estudian los géneros Amadotrogus Reitter, 1902; Amphimallina Reitter, 1905; Amphimallon Berthold, 1827; Geotrogus Guérin-Méneville, 1842; Monotropus Erichson, 1847; Pseudoapeterogyna Escalera, 1914 y Rhizotrogus Berthold, 1827, para comprobar la monofilia del grupo; evaluar sus relaciones filogenéticas; comprobar que la transferencia de especies de Rhizotrogus a Geotrogus y Monotropus estuvo bien establecida y describir la morfología externa y genitalia femenina y masculina de los géneros implicados. El análisis filogenético permite concluir que estos géneros constituyen un grupo monofilético. Sin embargo, poco se puede decir sobre las relaciones filogenéticas internas de este clado, las cuales permanecen en una politomia basal. Algunas de las especies transferidas de Rhizotrogus son consideradas un nuevo género Firminus. Los generos Amphimallina y Pseudoapterogyna son sinonimizados con Amphimallon y Geotrogus, respectivamente

Kinetic description of avalanching systems

Avalanching systems are treated analytically using the renormalization group (in the self-organized-criticality regime) or mean-field approximation, respectively. The latter describes the state in terms of the mean number of active and passive sites, without addressing the inhomogeneity in their distribution. This paper goes one step further by proposing a kinetic description of avalanching systems making use of the distribution function for clusters of active sites. We illustrate application of the kinetic formalism to a model proposed for the description of the avalanching processes in the reconnecting current sheet of the Earth magnetosphere.Comment: 9 page

El complejo karstico-yesifero subterráneo "Pedro Fernández" (Estremera, provincia de Madrid)

[Resumen] Se han analizado los factores originales de este morfosistema kárstico subterraneo, detallan do los procesos responsables de su génesis, así como la morfolmgía interior. Diferenciando los tipos de galerias y su evolución. Al mismo tiempo, se aportan determinadas consideraciones acerca de la sedimentación interior de la cavidad, su tipología e interpretación de su significado[Resumé] On a analysé les facteurs qui ont originé ce morphosysthéme karstique souterrain, en detallant le procesus responsable de leur genére, ainsi que leur morphilogie intérieure. En distinguant les types de galeries et leur évolution. Eu méme temps, on apporte certaines considerations données á propos de la sédimentation, sa typologie et interprétation de sa signification

A nonlinear land use regression approach for modelling NO2 concentrations in urban areas—Using data from low-cost sensors and diffusion tubes

Land Use Regression (LUR) based on multiple linear regression model is one of the techniques used most frequently for modelling the spatial variability of air pollution and assessing exposure in urban areas. In this paper, a nonlinear generalised additive model is proposed for LUR and its performance is compared to a linear model in Sheffield, UK for the year 2019. Pollution models were estimated using NO2 measurements obtained from 188 diffusion tubes and 40 low-cost sensors. Performance of the models was assessed by calculating several statistical metrics including correlation coefficient (R) and root mean square error (RMSE). High resolution (100 m × 100 m) maps demonstrated higher levels of NO2 in the city centre, eastern side of the city and on major roads. The results showed that the nonlinear model outperformed the linear counterpart and that the model estimated using NO2 data from diffusion tubes outperformed the models using data from low-cost sensors or both low-cost sensors and diffusion tubes. The proposed method provides a basis for further application of advanced nonlinear modelling approaches to constructing LUR models in urban areas which enable quantifying small scale variability in pollution levels

Ace inhibition and cardiovascular mortality and morbidity in essential hypertension: The end of the search or a need for further investigations?

Scientific evidence currently available supports the concept that renin-angiotensin blockade with angiotensin converting enzyme inhibitors as a first-line treatment exhibits in arterial hypertension beneficial effects in the prevention of mortality and morbidity comparable to those achieved with diuretics and β-blockers. In addition, the renin-angiotensin blockade has also proved to be beneficial in the secondary prevention of several complications of hypertensive disease such as after myocardial infarction and congestive heart failure, as well as in the prevention of the incidence of type 2 diabetes, and the progression of diabetic and nondiabetic nephropathy. In this later regard, recent evidence with angiotensin II receptor antagonists in reducing the progression of nephropathy in type 2 diabetes strongly confirms that antagonism of the renin-angiotensin system is an effective approach to cardiovascular and renal disease. Finally, the renin-angiotensin blockade in high-risk patients may reduce cardiovascular mortality independently of the effect on blood pressure (BP). The effect of other antihypertensive drugs on cardiovascular risk in patients with high-normal BP should be investigated to establish whether they exhibit a comparable effect or whether there is a class-related benefit of drugs blocking the renin-angiotensin system. Such a strategy could also be encouraged to design future interventional studies with the newer classes of compounds (angiotensin II AT1-receptor antagonists, vasopeptidase inhibitors, endothelin antagonists), which would have the additional potential advantage of providing information more easily transferable to large-scale clinical practice. Am J Hypertens 2002;15:367-371 © 2002 American Journal of Hypertension, Lt

Polypill in cardiovascular disease prevention: recent advances.

Triple therapy with lipid‑lowering, antihypertensive, and antiplatelet agents reduces the risk of recurrent cardiovascular fatal and nonfatal events, cardiovascular mortality, and total mortality in secondary prevention. In real life, however, effective implementation of these optimal treatments both in primary and secondary prevention is low, and thus their contribution to cardiovascular prevention is much lower than it could be, based on research data. One of the main barriers to the adequate implementation of these strategies is low adherence to the elevated number of pills, as adherence is adversely affected by the complexity of the prescribed treatment regimen, and can be considerably improved by treatment simplification. This review updates the findings provided by recent epidemiological and clinical studies favoring a polypill‑based approach to cardiovascular prevention. The increased prevalence of patients with multiple cardiovascular risk factors and comorbidities provides the rationale for a therapeutic strategy based on a combination of drugs against different risk factors in a single pill. Pharmacologic studies have demonstrated that different cardiovascular drugs can be combined in a single pill with no loss of their individual efficacy, and this favors adherence to and persistence of treatment, as well as multiple risk factor control. Recently, a randomized clinical trial SECURE (Secondary Prevention of Cardiovascular Disease in the Elderly) has shown a significant, 30% reduction in cardiovascular events, and a 33% reduction in cardiovascular death in patients after myocardial infarction treated with a polypill, as compared with usual care, thus supporting the polypill use as an integral part of any cardiovascular prevention strategy.S