Several studies of the electronic and vibrational structure of CF+ have been performed since this molecule was first discovered to occur in the interstellar medium, and even before that. However, researchers have paid little attention to calculating its Franck–Condon factors (FCFs), which can aid the identification of this molecule through comparison with the observed intensity spectrum. In this work, an analysis of all of the potential energy curves of CF+ that were candidates for this kind of calculation was undertaken. The Franck–Condon factors of CF+ were calculated using a supervised neural network with two layers and a variable learning rate.

In this work the available information from scientific and technical studies is compiled and analyzed, to determine the taxonomic composition and trophic structure of river communities belonging to five hydrological basins of Chile, located within an arid-Mediterranean environmental gradient. The basins were: Loa, Huasco, Limari, Cachapoal y Mataquito. The four most important taxonomic groups were considered: fish, benthic macroinvertebrates, macrofites and benthic diatoms. The taxonomic and trophic structures of 10 communities from the studied basins were determined. The analyses indicated that: (a) each basin shows a characteristic taxonomic structure; (b) no patterns were found of increase or decrease in diversity along the arid-Mediterranean gradient, only finding a pattern along the upstream-downstream gradient within a system; (c) benthic macroinvertebrates shows a taxonomic particular and differentiable composition for the zones arid, semiarid and Mediterranean; (d) the taxonomic composition of each group was found to be significantly nested between rivers, and (e) five types of food webs were identified for the total of studied community systems, represented by functional groups and their feeding relationships. Future research should be oriented towards increasing the taxonomic resolution of the food webs and incorporate other relevant functional features.

En este trabajo se recopila y analiza la informacion disponible contenida en estudios cientificos y tecnicos a fin de determinar la composicion taxonomica y la estructura trofica de comunidades de rios pertenecientes a cinco cuencas hidrograficas de Chile, ubicadas en un gradiente ambiental arido-mediterraneo. Las cuencas fueron: Loa, Huasco, Limari, Cachapoal y Mataquito. Se consideraron los cuatro grupos taxonomicos mas importantes: peces, macroinvertebrados bentonicos, macrofitas y diatomeas bentonicas. Se logro determinar la estructura taxonomica y trofica para 10 comunidades pertenecientes a las cuencas estudiadas. Los analisis indicaron que: (a) cada cuenca muestra una estructura taxonomica caracteristica; (b) no se aprecian patrones de aumento o disminucion de diversidad en el sentido del gradiente arido-mediterraneo, existiendo solo un patron en el gradiente aguas abajo-aguas arriba dentro de un sistema; (c) el grupo de los macroinvertebrados bentonicos muestra una composicion taxonomica particular y diferenciable para las zonas arida, semiarida y mediterranea; (d) la composicion taxonomica de cada grupo resulto significativamente anidada entre rios y (e) se identificaron cinco tipos de mallas troficas para el total de sistemas comunitarios estudiados, representadas por grupos funcionales y sus relaciones alimentarias. Investigaciones futuras deben orientarse a aumentar la resolucion taxonomica de la representacion de las mallas troficas e incorporar otros aspectos funcionales relevantes.

The unitary operator V(t) that diagonalizes the time-dependent quadratic Hamiltonian (TDQH) into a time-dependent harmonic oscillator (TDHO) is obtained using a Lie algebra. The method involves a factorization of the TDQH into a TDHO through a unitary Bogoliubov transformation in terms of creation and annihilation operators with time-dependent coefficients. It is shown that this operator can be easily achieved by means of the factorization, together with the commonly known Wei–Norman theorem. We discuss the conditions under which this unitary operator converges to the evolution operator U(t) of the Schrödinger equation for the TDQH, giving then a straightforward calculation of the evolution operator with respect to the procedures published in the literature.

El desarrollo de métodos para evaluar de manera rápida y efectiva un sistema hidrográfico, pero sin perder la capacidad de integrar información de la salud del sistema, ha despertado un alto interés en el último tiempo. El presente estudio evaluó la condición ecológica de la parte alta del estero Ñonguen (primero cinco kilómetros) durante dos periodos estacionales, evaluando 5 transectos de 100 metros, separadas aproximadamente por un kilómetro. Para ello se aplicaron dos índices desarrollados para climas mediterráneos en la península ibérica: el índice de calidad de ribera (QBR) y el índice de habitat fluvial (IHF). Los resultados indican que estos índices entregan una aproximación confiable de la calidad de la ribera del río y del cauce mismo. Se discute sobre su adaptabilidad para sistemas fluviales en general.The development of methods that allow us to evaluate quickly and efficiently a freshwater system has been of high interest in the last time. This work evaluated the ecological condition of the headwater of the Ñonguen stream (first five kilometers) during two seasonal periods, evaluating 5 transect of 100 m. separate by one kilometers each other. Two indexes development to mediterranean climate in the Iberian Peninsula was appliqued: the QBR (to evaluate riparian quality) and IHF (to evaluate physical habitat) index. The results shows the efficiency of these indexes like rapid assessments of environmental quality to shows a first trustworthy approximation of the hydrological system. The application of these indexes to freshwater system in general are discuss.

The prevalence of CD36 deficiency in East Asian and African populations suggests that the causal variants are under selection by severe malaria. Previous analysis of data from the International HapMap Project indicated that a CD36 haplotype bearing a nonsense mutation (T1264G; rs3211938) had undergone recent positive selection in the Yoruba of Nigeria. To investigate the global distribution of this putative selection event, we genotyped T1264G in 3420 individuals from 66 populations. We confirmed the high frequency of 1264G in the Yoruba (26%). However, the 1264G allele is less common in other African populations and absent from all non-African populations without recent African admixture. Using long-range linkage disequilibrium, we studied two West African groups in depth. Evidence for recent positive selection at the locus was demonstrable in the Yoruba, although not in Gambians. We screened 70 variants from across CD36 for an association with severe malaria phenotypes, employing a case-control study of 1350 subjects and a family study of 1288 parent-offspring trios. No marker was significantly associated with severe malaria. We focused on T1264G, genotyping 10,922 samples from four African populations. The nonsense allele was not associated with severe malaria (pooled allelic odds ratio 1.0; 95% confidence interval 0.89-1.12; P = 0.98). These results suggest a range of possible explanations including the existence of alternative selection pressures on CD36, co-evolution between host and parasite or confounding caused by allelic heterogeneity of CD36 deficiency.

El desarrollo de métodos para evaluar de manera rápida y efectiva un sistema hidrográfico, pero sin perder la capacidad de integrar información de la salud del sistema, ha despertado un alto interés en el último tiempo.El presente estudio evaluó la condición ecológica de la parte alta del estero Nonguén (primero cinco kilómetros) durante dos periodos estacionales, evaluando 5 transectos de 100 metros, separadas aproximadamente por un kilómetro.Para ello se aplicaron dos índices desarrollados para climas mediterráneos en la península ibérica: el índice de calidad de ribera (QBR) y el índice de hábitat fluvial (IHF).Los resultados indican que estos índices entregan una aproximación confiable de

The development of methods that allow us to evaluate quickly and ef ficiently a freshwater system has been of high interest in the last time. This work evaluated the ecological condition of the headwater of the Nonguen stream (first five kilometers) during two seasonal periods, evaluating 5 transect of 100 m. separate by one kilometers each other . Two indexes development to mediterranean climate in the Iberian Peninsula was appliqued: the QBR (to evaluate riparian quality) and IHF (to evaluate physical habitat) index. The results shows the efficiency of these indexes like rapid assessments of environmental quality to shows a first trustworthy approximation of the hydrological system. The application of these indexes to freshwater system in general are discuss.

Several factors influence the latitudinal distributions of organisms, including habitat heterogeneity, ecological requirements, historical events, and the influence of temperature and latitude, amongst others. We evaluate the distributions and diversity of Plecoptera on local (latitudinal gradient in Chile) and global scales. In Chile, 66 species from 35 genera and 6 families are recognized, with an endemism of 60 %. Species richness is greatest between the Maipo and Aysén river basins (34-45°S), and especially in the Valdivia region (39-40°S). The most widely distributed species are Limnoperla jaffueli and Antarctoperla michaelseni. The results of this work extend the distribution of several species and suggest that the latitudinal distribution of the order responds mainly to sampling effort, although lower differences in latitudinal diversity are expected due to the characteristics of Chilean rivers (except in the dry zone, 17-30°S). The two ecological factors that seem to be the most important in Plecoptera distributions, in Chile and around the world, are cold temperatures and good water quality. Thus, at global scale, diversity increases from the Equator toward the poles, with differences in the number of families and species between the Southern and Northern hemispheres, possibly due to differences in the number of studies done at the species level.

El uso de macroinvertebrados bentonicos como indicadores biologicos es de larga tradicion en los paises desarrollados y son incorporados en todas las evaluaciones de calidad ecologica de sistemas fluviales. En America Latina estos estudios son menos frecuentes y las normativas para la proteccion de los recursos acuaticos recien comienzan a elaborarse, como es el caso de Chile, dejando abierta la posibilidad al uso de criterios biologicos. El presente estudio realiza una adaptacion de indices bioticos (IBE, BMWP, IBF y SIGNAL) los que son aplicados y comparados en una cuenca mediterranea de Chile, el rio Chillan. Los resultados muestran el mismo patron de comportamiento para todos los indices, definiendo areas en buen estado y otras fuertemente impactadas desde el punto de vista biologico. Sin embargo, el IBF y el SIGNAL son mas sensibles a perturbaciones no detectadas por el IBE y BMWP. Se discute la factibilidad de aplicacion y ventajas que ofrece cada uno de los indices, permitiendo hacer una propuesta metodologica para Chile central

Recently, there has been some interest in finding exact solutions to the time-dependent Schrodinger equation, specifically in the case of a time-dependent linear potential, though surprisingly in all those works very cumbersome methods are used. In the present report we want to emphasize that there exists another method, quite general and simple, to solve such kind of problems. The method was proposed several years ago and it is based on the so called Wei-Norman theorem.

Developed countries have traditionally used benthic macroinvertebrates as biological indicators, incorporating them into the environmental quality evaluations of fluvial systems. These studies are less frequent in Latin America, where the environmental protection standards for aquatic resources are just beginning to be elaborated. Thus, in Chile, the use of biocriteria for such studies remains a possibility. This study of the Chilldn River (Chile) adapts these biotic indexes (IBE, BMWP, IBF, and SIGNAL) for their application and comparison in a Mediterranean basin. The results showed the same behavior pattern for all indexes, defining some areas as having good conditions and others, which, from a biological perspective, have been strongly impacted. Specifically, the IBF and SIGNAL indexes are more sensitive to disturbances than the IBE and BMWP. Application feasibility and the advantages of the different indices are discussed, proposing a new methodology for central Chile.

El uso de macroinvertebrados bentónicos como indicadores biológicos es de larga tradición en los países desarrollados y son incorporados en todas las evaluaciones de calidad ecológica de sistemas fluviales. En América Latina estos estudios son menos frecuentes y las normativas para la protección de los recursos acuáticos recién comienzan a elaborarse, como es el caso de Chile, dejando abierta la posibilidad al uso de criterios biológicos. El presente estudio realiza una adaptación de índices bióticos (IBE, BMWP, IBF y SIGNAL) los que son aplicados y comparados en una cuenca mediterránea de Chile, el río Chillan. Los resultados muestran el mismo patrón de comportamiento para todos los índices, definiendo áreas en buen estado y otras fuertemente impactadas desde el punto de vista biológico. Sin embargo, el IBF y el SIGNAL son más sensibles a perturbaciones no detectadas por el IBE y BMWP. Se discute la factibilidad de aplicación y ventajas que ofrece cada uno de los índices, permitiendo hacer una propuesta metodológica para Chile centralDeveloped countries have traditionally used benthic macroinvertebrates as biological indicators, incorporating them into the environmental quality evaluations of fluvial systems. These studies are less frequent in Latin America, where the environmental protection standards for aquatic resources are just beginning to be elaborated. Thus, in Chile, the use of biocriteria for such studies remains a possibility. This study of the Chilian River (Chile) adapts these biotic indexes (IBE, BMWP, IBF, and SIGNAL) for their application and comparison in a Mediterranean basin. The results showed the same behavior pattern for all indexes, defining some areas as having good conditions and others, which, from a biological perspective, have been strongly impacted. Specifically, the IBF and SIGNAL indexes are more sensitive to disturbances than the IBE and BMWP. Application feasibility and the advantages of the different indices are discussed, proposing a new methodology for central Chile

The macrozoobenthos colonization process on artificial substrata in lotic environments was evaluated. Two seasonal periods, autumn–winter and spring–summer, of a relatively undisturbed fluvial system, the Estero Nonguén (VIII Region, Chile), have been studied. Five stations, two in riffles and three on sandy bottoms, extending from a head water stream to 5 km down river, were sampled. For all stations and for each season the results were as follows: (a) 32% of the total number of taxa found in this study colonized the artificial substrata on the first day of exposure, (b) the taxa that colonized sandy bottoms were typical for riffle, (c) the colonization process showed the same abundance, specific and cumulative richness and diversity patterns over time, and (d) equilibrium was reached approximately 2 weeks after initial exposure. This suggests that “Estero Nonguén” stream presents a nearly pristine condition and can be considered as a reference site to carry out biodiversity and ecosystem functionality studies, and giving information on time recovery for sectors previously disturbed.

SUMMARY Macroinvertebrates have been used for decades to evaluate water quality, using measures of diversity, biotic indexes and comparative analysis. The taxonomic level of family allows a general interpretation of the ecological quality of a fluvial system, and is possible to infer the quality of these systems compared to selected references sites. This paper analyzed three localities of CentralSouth Chile by means of grouping analysis, evaluating if there is any loss of information when using two hierarchic levels. It is shown that the family level of benthic macroinvertebrates is sufficient for environmental monitoring. The practical advantages, the integrating capacity that can be reached and its relation with environmental variables are discussed.

Pathogens have played a substantial role in human evolution, with past infections shaping genetic variation at loci influencing immune function. We selected 168 genes known to be involved in the immune response, genotyped common single nucleotide polymorphisms across each gene in three population samples (CEPH Europeans from Utah, Han Chinese from Guangxi, and Yoruba Nigerians from Southwest Nigeria) and searched for evidence of selection based on four tests for non-neutral evolution: minor allele frequency (MAF), derived allele frequency (DAF), Fst versus heterozygosity and extended haplotype homozygosity (EHH). Six of the 168 genes show some evidence for non-neutral evolution in this initial screen, with two showing similar signals in independent data from the International HapMap Project. These analyses identify two loci involved in immune function that are candidates for having been subject to evolutionary selection, and highlight a number of analytical challenges in searching for selection in genome-wide polymorphism data.

In this work we discuss some mathematical aspects and important applications of the operator algebra to several problems. Part of the results here presented have been published elsewhere and represent contributions set down along several years of research. We begin by discussing the mathematical structure of the Franck-Condon integral and the associated Lie algebraic formulation, as well as some connections with the concept of squeezed states. We also consider the operator algebra solution of the Schrodinger equation with a time-dependent periodic Hamiltonian by means of standard operator algebra techniques and by using the concept of the Bargmann-Segal space. In the final section of this report we include some unpublished material on the Lie algebraic approach to the Floquet quasi-energies.

Se estudió la dieta alimentaria de Oncorhynchus mykiss (Walbaum 1792) en un ecosistema fluvial con baja intervención antrópica determinando si hay correspon-dencia entre los ítemes consumidos por el pez y la oferta alimentaria. El área de estudio corresponde al estero Nonguén, una subcuenca costera tributaria del curso inferior del río Andalién (36° 49' a 36° 54'S; 72° 57' a 73° 01'W), que con una orientación general de sur a norte, recorre una distancia de más de 15 km dando forma a una cuenca de 44 km² de superficie. El estudio fue abordado mediante pesca eléctrica en dos períodos estacionales: invierno y primavera. Para ello se definió una secuencia lineal de 5 estaciones de muestreos localizadas en los sectores de ritrón y potamón en los primeros 5 kilómetros del estero. El espectro trófico identificado fue de 30 taxa, constituido básicamente por larvas de Ephemeroptera, Plecoptera, Trichoptera y Diptera. La dieta entre estaciones es similar (ISP 50%), donde Oncorhynchus mykiss se comportaría como un depredador generalista (Spearman rs = 0,45 p<0,05)The diet of O. mykiss (Walbaum 1792) in a fluvial ecosystem with low anthropic intervention was studied, determining if there is correspondence between items consumed by the fish and the nourishing supply. The study area corresponds to Nonguen stream, a tributary coastal subriver basin of the inferior course of Andalien river (36° 49' - 57' 36° 54'S; 72°- 73° 01'W), with a general direction of the South to North, crossing a distance more than 15 km with a watershed of 44 km². The study was carried out by means of electrical fishing in two seasonal periods: winter and spring. Along a linear sequence of 5 sampling stations located in ritron and potamon sectors in the first 5 kilometers of the stream. The identified throfic spectrum consists of 30 taxa, composed basically by larvae of Ephemeroptera, Plecoptera, Trichoptera and Diptera. The diet between stations is similar (ISP 50%) indicating that Oncorhynchus mykiss behaves as a generalist predator (Spearman rs = 0,45 p<0,05).