Quasi-Exact Solvability and the direct approach to invariant subspaces

We propose a more direct approach to constructing differential operators that preserve polynomial subspaces than the one based on considering elements of the enveloping algebra of sl(2). This approach is used here to construct new exactly solvable and quasi-exactly solvable quantum Hamiltonians on the line which are not Lie-algebraic. It is also applied to generate potentials with multiple algebraic sectors. We discuss two illustrative examples of these two applications: an interesting generalization of the Lam\'e potential which posses four algebraic sectors, and a quasi-exactly solvable deformation of the Morse potential which is not Lie-algebraic.Comment: 17 pages, 3 figure

The Broad Concept of "Spasticity-Plus Syndrome" in Multiple Sclerosis: A Possible New Concept in the Management of Multiple Sclerosis Symptoms

Multiple sclerosis (MS) pathology progressively affects multiple central nervous system (CNS) areas. Due to this fact, MS produces a wide array of symptoms. Symptomatic therapy of one MS symptom can cause or worsen other unwanted symptoms (anticholinergics used for bladder dysfunction produce impairment of cognition, many MS drugs produce erectile dysfunction, etc.). Appropriate symptomatic therapy is an unmet need. Several important functions/symptoms (muscle tone, sleep, bladder, pain) are mediated, in great part, in the brainstem. Cannabinoid receptors are distributed throughout the CNS irregularly: There is an accumulation of CB1 and CB2 receptors in the brainstem. Nabiximols (a combination of THC and CBD oromucosal spray) interact with both CB1 and CB2 receptors. In several clinical trials with Nabiximols for MS spasticity, the investigators report improvement not only in spasticity itself, but also in several functions/symptoms mentioned before (spasms, cramps, pain, gait, sleep, bladder function, fatigue, and possibly tremor). We can conceptualize and, therefore, hypothesize, through this indirect information, that it could be considered the existence of a broad "Spasticity-Plus Syndrome" that involves, a cluster of symptoms apart from spasticity itself, the rest of the mentioned functions/symptoms, probably because they are interlinked after the increase of muscle tone and mediated, at least in part, in the same or close areas of the brainstem. If this holds true, there exists the possibility to treat several spasticity-related symptoms induced by MS pathology with a single therapy, which would permit to avoid the unnecessary adverse effects produced by polytherapy. This would result in an important advance in the symptomatic management of MS

Systemic Effects Induced by Hyperoxia in a Preclinical Model of Intra-abdominal Sepsis

Supplemental oxygen is a supportive treatment in patients with sepsis to balance tissue oxygen delivery and demand in the tissues. However, hyperoxia may induce some pathological effects. We sought to assess organ damage associated with hyperoxia and its correlation with the production of reactive oxygen species (ROS) in a preclinical model of intra-abdominal sepsis. For this purpose, sepsis was induced in male, Sprague-Dawley rats by cecal ligation and puncture (CLP). We randomly assigned experimental animals to three groups: control (healthy animals), septic (CLP), and sham-septic (surgical intervention without CLP). At 18 h after CLP, septic (n = 39), sham-septic (n = 16), and healthy (n = 24) animals were placed within a sealed Plexiglas cage and randomly distributed into four groups for continuous treatment with 21%, 40%, 60%, or 100% oxygen for 24 h. At the end of the experimental period, we evaluated serum levels of cytokines, organ damage biomarkers, histological examination of brain and lung tissue, and ROS production in each surviving animal. We found that high oxygen concentrations increased IL-6 and biomarkers of organ damage levels in septic animals, although no relevant histopathological lung or brain damage was observed. Healthy rats had an increase in IL-6 and aspartate aminotransferase at high oxygen concentration. IL-6 levels, but not ROS levels, are correlated with markers of organ damage. In our study, the use of high oxygen concentrations in a clinically relevant model of intra-abdominal sepsis was associated with enhanced inflammation and organ damage. These findings were unrelated to ROS release into circulation. Hyperoxia could exacerbate sepsis-induced inflammation, and it could be by itself detrimental. Our study highlights the need of developing safer thresholds for oxygen therapy

Cosmological constraints on the magnification bias on sub-millimetre galaxies after large-scale bias corrections

Context. The study of the magnification bias produced on high-redshift sub-millimetre galaxies by foreground galaxies through the analysis of the cross-correlation function was recently demonstrated as an interesting independent alternative to the weak-lensing shear as a cosmological probe. Aims. In the case of the proposed observable, most of the cosmological constraints mainly depend on the largest angular separation measurements. Therefore, we aim to study and correct the main large-scale biases that aect foreground and background galaxy samples to produce a robust estimation of the cross-correlation function. Then we analyse the corrected signal to derive updated cosmological constraints. Methods. We measured the large-scale, bias-corrected cross-correlation functions using a background sample of H-ATLAS galaxies with photometric redshifts >1.2 and two dierent foreground samples (GAMA galaxies with spectroscopic redshifts or SDSS galaxies with photometric ones, both in the range 0.2 < z < 0.8). These measurements are modelled using the traditional halo model description that depends on both halo occupation distribution and cosmological parameters. We then estimated these parameters by performing a Markov chain Monte Carlo under multiple scenarios to study the performance of this observable and how to improve its results. Results. After the large-scale bias corrections, we obtain only minor improvements with respect to the previous magnification bias results, mainly confirming their conclusions: a lower bound on m > 0:22 at 95% CL and an upper bound 8 < 0:97 at 95% CL (results from the zspec sample). Neither the much higher surface density of the foreground photometric sample nor the assumption of Gaussian priors for the remaining unconstrained parameters significantly improve the derived constraints. However, by combining both foreground samples into a simplified tomographic analysis, we were able to obtain interesting constraints on the m8 plane as follows: m = 0:50+0:14 0:20 and 8 = 0:75+0:07 0:10 at 68% C

Follow-up observations at 16 and 33 GHz of extragalactic sources from WMAP 3-year data: I - Spectral properties

We present follow-up observations of 97 point sources from the Wilkinson Microwave Anisotropy Probe (WMAP) 3-year data, contained within the New Extragalactic WMAP Point Source (NEWPS) catalogue between declinations of -4 and +60 degrees; the sources form a flux-density-limited sample complete to 1.1 Jy (approximately 5 sigma) at 33 GHz. Our observations were made at 16 GHz using the Arcminute Microkelvin Imager (AMI) and at 33 GHz with the Very Small Array (VSA). 94 of the sources have reliable, simultaneous -- typically a few minutes apart -- observations with both telescopes. The spectra between 13.9 and 33.75 GHz are very different from those of bright sources at low frequency: 44 per cent have rising spectra (alpha < 0.0), where flux density is proportional to frequency^-alpha, and 93 per cent have spectra with alpha < 0.5; the median spectral index is 0.04. For the brighter sources, the agreement between VSA and WMAP 33-GHz flux densities averaged over sources is very good. However, for the fainter sources, the VSA tends to measure lower values for the flux densities than WMAP. We suggest that the main cause of this effect is Eddington bias arising from variability.Comment: 12 pages, 13 figures, submitted to MNRA

Fortaleciendo los h?bitos lectores implementando la literatura infantil como estrategia l?dico pedag?gica para enriquecer las habilidades comunicativas de los ni?os y ni?as del grado preescolar

116 p. Recurso Electr?nicoEl presente proyecto de investigaci?n centra su acci?n en estimular desde edades tempranas, la lectura y el acercamiento a los libros, como v?a para desarrollar h?bitos lectores y enriquecer las habilidades comunicativas. Tiene como objetivo fijar en el ni?o el h?bito de la lectura donde el principal factor es determinar aquellas posibles causas que propician o desmotivan a los ni?os el deseo de leer dentro de su mundo, aprender a tener un h?bito lector a temprana edad se ve como una necesidad en el desarrollo personal y social de cada uno de los ni?os, por eso vemos necesidad o alternativa de desarrollar estrategias l?dico pedag?gicas como la literatura infantil, por medio de un proyecto pedag?gico de aula para fortalecer h?bitos lectores, que le permitan transformar su inteligencia creadora, mejorar sus competencias comunicativas entre las que aparecen, leer, escribir, hablar y escuchar adem?s permite acercarlos de manera agradable a los textos. Conforme con esto, se tiene como referencia la investigaci?n formativa, de igual manera un modelo de investigaci?n cualitativo con enfoque etnogr?fico, con ?nfasis participativo y cooperativo, utilizando instrumentos como entrevistas, cuestionarios entre otros dentro del desarrollo del proyecto. El cual se llev? mediante dos fases, la primera se hizo mediante la observaci?n de la cual se detect? una problem?tica y la segunda en la cual se hizo una intervenci?n mediante el proyecto pedag?gico de aula, que dio paso a la participaci?n activa de toda una comunidad educativa. Palabras clave: literatura ? lectura ? h?bitos ? cuentos ? habilidades comunicativasThe present research project focuses on stimulating reading and the approaching to books from early ages, as a way to develop reading habits and enriching communicative skills. Its aim is to establish the habit of reading in children, where the main factor is to determine those possible causes that encourage or discourage children the desire to read within their world; learning to acquire a reading habit at an early age is seen as a necessity in the personal and social development of each child, thus, it is seen the necessity or alternative to implement dynamic-pedagogical strategies such as children's literature, through a pedagogical classroom project to strengthen reading habits, that allows him to transform his creative intelligence and to improve his communicative competences such as, reading, writing, speaking and listening; it also allows to connect them in a pleasant way to texts. Accordingly, the research is based on formative research, as well as a qualitative research model with an ethnographic approach, with a participative and cooperative emphasis, using instruments such as interviews, questionnaires and others within the project development. This was carried out in two phases: the first one was done through the observation in which a problematic was detected and the second one, where an intervention was made through the classroom pedagogical project, which gave way to the active participation of an entire educational community. Keywords: Literature - reading - habits - stories - communicative skill

Temperature but not leptin prevents semi-starvation induced hyperactivity in rats: implications for anorexia nervosa treatment

The hypothesis linking hyperactivity with weight loss associated hypoleptinemia in anorexia nervosa gained momentum after a study showing that leptin suppressed semi-starvation induced hyperactivity in rats. Alternatively, ambient temperature is a key modulating factor of activity in semi-starved rats. The aim of the study is to compare the efficacy of leptin with increased ambient temperature in the prevention of hyperactivity in semi-starved rats. 74 Sprague-Dawley male rats were employed in two experiments with the difference residing in the length of baseline. After an extended (28 days), or shorter (14 days) baseline with free access to food and the running wheel, housed at 21 degrees C, animals were either ad-lib feed or food restricted (60% of food ingested during previous week) and infused with same amount of leptin at 21 degrees C, 25 degrees C, or vehicle at 21 degrees C, 25 degrees C and 32 degrees C for a week. Animals housed at 32 degrees C significantly reduced wheel running and weight loss during food restriction while animals given leptin did not yield no differences in activity or weight loss. Moreover, unlike animals housed at 32 degrees C, body temperature of leptin infused animals housed at 21 degrees C was significantly reduced during food restriction. Furthermore, leptin treated rats without a preceding stable pattern of activity displayed a severe dysregulation of circadian rhythm in activity and a collapse of body temperature. Housing temperature plays a more critical role than leptin in the regulation of semi-starvation induced hyperactivity in rats, which may be of relevance for the management of hyperactivity in anorexia nervosa