Dinámica espacio temporal en la ecología trófica de la anchoveta (Engraulis ringens Jenyns, 1842; pisces: engraulide) en el mar peruano

El objetivo de este trabajo es estudiar las variaciones ontogénicas, espaciales y nictemerales en la dieta de la anchoveta peruana (Engraulis ringens). El trabajo se basa en el análisis de contenido estomacal de 13 430 anchovetas (peces de 4 a 19,5 cm) muestreados durante 22 cruceros de investigación realizados a bordo de las embarcaciones científicas del Instituto del Mar del Perú durante el período 1996-2003. Previo a los análisis estadísticos la contribución de cada grupo de presa fue convertido a carbonó. Los datos fueron procesados por medio de estadística uni y multivariada en función de la talla de la anchoveta, la latitud, la distancia de la costa, la distancia del borde de la plataforma continental y el período nictemeral. Los resultados enseñan que la anchoveta se alimenta mayormente de zooplancton cualquier sea su tamaño o su distribución espaciotemporal. La anchoveta cambio gradualmente su dieta a lo largo de su ciclo de vida. Así, los individuos mas pequeños han ingerido mayormente copépodos calanoideos (68.0%) y eufausidos (23.3%), mientras que los individuos mas grandes ingirieron mayormente eufausidos (84.9%) y copépodos calanoideos (11.5%). Latitudinalmente, la mayor contribución de los copépodos calanoideos se observó en las zonas de afloramiento de Chicama y San Juan, con el 52.3% y 47.5%, respectivamente. Hasta los 160 km de distancia de la costa, no se ha observado un patrón regular en la contribución de las principales presas, mientras que por fuera, se insinúa un patrón caracterizado por el predominio de los eufausidos (>84%) y la menor contribución de copépodos calanoideos (<14,1%). En la plataforma continental los eufausidos contribuyeron con el 55.6% y los copépodos calanoideos con el 36.9%; mientras que por fuera de esa zona, los eufausidos se incrementaron al 75.3% y los copépodos calanoideos disminuyeron al 20.1%. Al considerar el período nictemeral, el ítem presa predominante durante el día fueron los eufausidos (52.7%) seguido de los copépodos calanoideos (40.9%); mientras que durante la noche, los eufausidos se incrementaron al 80.2% y los copépodos calanoideos disminuyeron al 15.7%. Estos resultados contradicen lo que se conocía acerca de la variabilidad de la dieta de la anchoveta, desestimándose: (i) que en el norte es fitoplanctívora y en el sur es zooplanctívora; (ii) que la fracción zooplanctónica es mayor en la zona oceánica. Asimismo, se ha demostrado que: (i) la anchoveta es principalmente zooplanctófaga durante su ciclo de vida, con modificaciones que corresponden a la mayor ingesta de presas pequeñas cuando son juveniles y de presas grandes cuando son adultas, (ii) en la zona de influencia de la plataforma continental consume aproximadamente el doble de copépodos calanoideos que en la zona oceánica, y aproximadamente una tercera parte menos de eufausidos en la zona interna que en la zona oceánica, y (iii) durante la noche y el día ingiere principalmente eufausidos pero la contribución de los copépodos calanoideos sube al 40%.

Disponibilidade de fósforo em seis solos do Uruguai afetada pela variação temporal das condições de oxirredução

Os processos de oxirredução influem na reatividade dos óxidos de ferro no solo, o que pode afetar a disponibilidade do fósforo. Com o objetivo de avaliar como estes processos interferem na disponibilidade do fósforo, realizou-se um estudo com seis solos do Uruguai sujeitos a variações temporais nas condições de oxirredução. Amostras do horizonte A desses solos, com diferente material de origem e que ocupam posição topográfica plana e encostas baixas da paisagem, foram colocadas sob condições de alagamento por 5, 15 e 45 dias. Decorridos estes períodos de tempo, os materiais de solo foram secos durante um período de 21 dias e amostrados para análises químicas. As formas de ferro de baixa cristalinidade, extraídas pelo oxalato de amônio a pH 6 (Fe6), aumentaram com o alagamento dos solos e, após a secagem, decresceram, mas ficaram, entretanto, acima dos teores iniciais. Encontrou-se uma relação significativa entre o conteúdo de carbono orgânico dos solos e a proporção de formas de ferro de baixa cristalinidade, antes e depois dos diferentes períodos de alagamento. Os teores de fósforo disponível extraídos por Bray-1 aumentaram com o alagamento e, com exceção do solo Algorta, após a secagem dos solos, diminuíram para valores similares aos iniciais. O alagamento do solo e a posterior secagem determinaram o aumento das frações de ferro de maior reatividade, acarretando a adsorção de fósforo, evidenciado pelos menores teores de fósforo remanescentes na solução. Houve tendência muito definida de diminuição do fósforo na solução dos solos com o aumento dos teores de ferro em formas de alta reatividade química (Fe6). Estes resultados indicam que, após ciclos de alagamento-secagem do solo, a adsorção do fósforo aumenta pela reação com compostos de ferro recentemente precipitados, o que resulta em menor disponibilidade do fósforo para as plantas.

Integration of genome-wide association studies with biological knowledge identifies six novel genes related to kidney function.

In conducting genome-wide association studies (GWAS), analytical approaches leveraging biological information may further understanding of the pathophysiology of clinical traits. To discover novel associations with estimated glomerular filtration rate (eGFR), a measure of kidney function, we developed a strategy for integrating prior biological knowledge into the existing GWAS data for eGFR from the CKDGen Consortium. Our strategy focuses on single nucleotide polymorphism (SNPs) in genes that are connected by functional evidence, determined by literature mining and gene ontology (GO) hierarchies, to genes near previously validated eGFR associations. It then requires association thresholds consistent with multiple testing, and finally evaluates novel candidates by independent replication. Among the samples of European ancestry, we identified a genome-wide significant SNP in FBXL20 (P = 5.6 × 10(-9)) in meta-analysis of all available data, and additional SNPs at the INHBC, LRP2, PLEKHA1, SLC3A2 and SLC7A6 genes meeting multiple-testing corrected significance for replication and overall P-values of 4.5 × 10(-4)-2.2 × 10(-7). Neither the novel PLEKHA1 nor FBXL20 associations, both further supported by association with eGFR among African Americans and with transcript abundance, would have been implicated by eGFR candidate gene approaches. LRP2, encoding the megalin receptor, was identified through connection with the previously known eGFR gene DAB2 and extends understanding of the megalin system in kidney function. These findings highlight integration of existing genome-wide association data with independent biological knowledge to uncover novel candidate eGFR associations, including candidates lacking known connections to kidney-specific pathways. The strategy may also be applicable to other clinical phenotypes, although more testing will be needed to assess its potential for discovery in general.

Neuropsychological outcome after extra-temporal epilepsy surgery.

BACKGROUND: The neuropsychological results of temporal lobe epilepsy surgery are well reported in the literature. The aim of this study was to analyse the neuropsychological outcome in a consecutive series of patients with extra-temporal epilepsy. METHODS: We retrospectively analysed the data of patients operated between 1996 and 2008 for extra-temporal epilepsy. Standard neuropsychological tests were applied. We assessed the neuropsychological outcome after surgery and the correlation of the neuropsychological outcome with (1) side and localisation of surgery, (2) Engel scale for seizure outcome and (3) timing of surgery. FINDINGS: Patients had a better neuropsychological outcome when undergoing non-frontal resection [χ2 (2) =6.66, p = 0.036]. Subjects who had undergone left or right resection showed no difference in outcome [χ2 (2) =0.533, p = 0.766]. The correlation between the Engel scale for seizure re-occurence and the neuropsychological scores showed only a tendency for better outcome (Spearman ρ = -0.437; p = 0.069). The global measure of change did not correlate significantly with delay of surgery (Spearman ρ = -0.163; p = 0.518). CONCLUSIONS: Resective epilepsy surgery improves neuropsychological status outcome in patients with extra-temporal epilepsy even if the patient did not become seizure free. The outcome is better for non-frontal localisation.

Ecological temporal stability of Staphylococcus aureus nasal carriage.

We described the colonization dynamics of Staphylococcus aureus in a group of 266 healthy carriers over a period of approximately 1 year. We used precise genotyping methods, i.e., amplified fragment length polymorphism (AFLP), spa typing, and double-locus sequence typing (DLST), to detect changes in strain identity. Strain change took place rather rarely: out of 89 carriers who had initially been colonized, only 7 acquired a strain different from the original one. Approximately one-third of the carriers eliminated the colonization, and a similar number became newly colonized. Some of these events probably represent detection failure rather than genuine colonization loss or acquisition. Lower bacterial counts were associated with increased probability of eliminating the colonization. We have confirmed a high mutation rate in the spa locus: 6 out of 53 strains underwent mutation in the spa locus. There was no overall change in S. aureus genotype composition.

Temporal and spatial origin of Gesneriaceae in the New World inferred from plastid DNA sequences

Gesneriaceae are represented in the New World (NW) by a major clade (c. 1000 species) currently recognized as subfamily Gesnerioideae. Radiation of this group occurred in all biomes of tropical America and was accompanied by extensive phenotypic and ecological diversification. Here we performed phylogenetic analyses using DNA sequences from three plastid loci to reconstruct the evolutionary history of Gesnerioideae and to investigate its relationship with other lineages of Gesneriaceae and Lamiales. Our molecular data confirm the inclusion of the South Pacific Coronanthereae and the Old World (OW) monotypic genus Titanotrichum in Gesnerioideae and the sister-group relationship of this subfamily to the rest of the OW Gesneriaceae. Calceolariaceae and the NW genera Peltanthera and Sanango appeared successively sister to Gesneriaceae, whereas Cubitanthus, which has been previously assigned to Gesneriaceae, is shown to be related to Linderniaceae. Based on molecular dating and biogeographical reconstruction analyses, we suggest that ancestors of Gesneriaceae originated in South America during the Late Cretaceous. Distribution of Gesneriaceae in the Palaeotropics and Australasia was inferred as resulting from two independent long-distance dispersals during the Eocene and Oligocene, respectively. In a short time span starting at 34 Mya, ancestors of Gesnerioideae colonized several Neotropical regions including the tropical Andes, Brazilian Atlantic forest, cerrado, Central America and the West Indies. Subsequent diversification within these areas occurred largely in situ and was particularly extensive in the mountainous systems of the Andes, Central America and the Brazilian Atlantic forest. Only two radiations account for 90% of the diversity of Gesneriaceae in the Brazilian Atlantic forest, whereas half of the species richness in the northern Andes and Central America originated during the last 10 Myr from a single radiation.

B2B Integration in Global Supply Chains: An Identification of Technical Integration Scenarios

The competitiveness of businesses is increasingly dependent on their electronic networks with customers, suppliers, and partners. While the strategic and operational impact of external integration and IOS adoption has been extensively studied, much less attention has been paid to the organizational and technical design of electronic relationships. The objective of our longitudinal research project is the development of a framework for understanding and explaining B2B integration. Drawing on existing literature and empirical cases we present a reference model (a classification scheme for B2B Integration). The reference model comprises technical, organizational, and institutional levels to reflect the multiple facets of B2B integration. In this paper we onvestigate the current state of electronic collaboration in global supply chains focussing on the technical view. Using an indepth case analysis we identify five integration scenarios. In the subsequent confirmatory phase of the research we analyse 112 real-world company cases to validate these five integration scenarios. Our research advances and deepens existing studies by developing a B2B reference model, which reflects the current state of practice and is independent of specific implementation technologies. In the next stage of the research the emerging reference model will be extended to create an assessment model for analysing the maturity level of a given company in a specific supply chain.

Traducción técnica del capítulo III del libro Advanced Data Warehouse design: from conventional to spatial and temporal applications

The proposal to work on this final project came after several discussions held with Dr. Elzbieta Malinowski Gadja, who in 2008 published the book entitled Advanced Data Warehouse Design: From Conventional to Spatial and Temporal Applications (Data-Centric Systems and Applications). The project was carried out under the technical supervision of Dr. Malinowski and the direct beneficiary was the University of Costa Rica (UCR) where Dr. Malinowski is a professor at the Department of Computer Science and Informatics. The purpose of this project was twofold: First, to translate chapter III of said book with the intention of generating educational material for the use of the UCR and, second, to venture in the field of technical translation related to data warehouse. For the first component, the goal was to generate a final product that would eventually serve as an educational tool for the post-graduate courses of the UCR. For the second component, this project allowed me to acquire new skills and put into practice techniques that have helped me not only to perfom better in my current job as an Assistant Translator of the Inter-American BAnk (IDB), but also to use them in similar projects. The process was lenggthy and required torough research and constant communication with the author. The investigation focused on the search of terms and definitions to prepare the glossary, which was the basis to start the translation project. The translation process itself was carried out by phases, so that comments and corrections by the author could be taken into account in subsequent stages. Later, based on the glossary and the translated text, illustrations had been created in the Visio software were translated. In addition to the technical revision by the author, professor Carme Mangiron was in charge of revising the non-technical text. The result was a high-quality document that is currently used as reference and study material by the Department of Computer Science and Informatics of Costa Rica.

Activation of a HIF1alpha-PPARgamma axis underlies the integration of glycolytic and lipid anabolic pathways in pathologic cardiac hypertrophy.

Development of cardiac hypertrophy and progression to heart failure entails profound changes in myocardial metabolism, characterized by a switch from fatty acid utilization to glycolysis and lipid accumulation. We report that hypoxia-inducible factor (HIF)1alpha and PPARgamma, key mediators of glycolysis and lipid anabolism, respectively, are jointly upregulated in hypertrophic cardiomyopathy and cooperate to mediate key changes in cardiac metabolism. In response to pathologic stress, HIF1alpha activates glycolytic genes and PPARgamma, whose product, in turn, activates fatty acid uptake and glycerolipid biosynthesis genes. These changes result in increased glycolytic flux and glucose-to-lipid conversion via the glycerol-3-phosphate pathway, apoptosis, and contractile dysfunction. Ventricular deletion of Hif1alpha in mice prevents hypertrophy-induced PPARgamma activation, the consequent metabolic reprogramming, and contractile dysfunction. We propose a model in which activation of the HIF1alpha-PPARgamma axis by pathologic stress underlies key changes in cell metabolism that are characteristic of and contribute to common forms of heart disease.

Complete Ontology- Three level Integration

This file contains the complete ontology (OntoProcEDUOC_OKI_Final.owl). At loading time to edit, the OKI ontology corresponding to the implementation level (OntoOKI_DEFINITIVA.owl)must be imported.

Variabilidade espacial e temporal da resistência mecânica do solo à penetração em áreas com e sem manejo químico localizado

O objetivo deste trabalho foi avaliar o comportamento das variabilidades (espacial e temporal) por meio da técnica de escalonamento de semivariogramas, da variável resistência mecânica do solo à penetração (RMSP) nas camadas de 0-0,1, 0,1-0,2, 0,2-0,3 m, para os anos de 1999 a 2001, sob duas formas de manejo: com manejo químico localizado (CML) e sem manejo químico localizado (SML). Os resultados demonstraram que a variável RMSP apresentou variabilidade espacial com comportamento distinto, conforme a camada e o ano de estudo. A variável RMSP apresentou variabilidade temporal tanto nas parcelas CML quanto nas parcelas SML. As duas formas de manejo (com manejo químico localizado (CML) e sem manejo químico localizado (SML)) não influenciaram o comportamento espacial da variável resistência mecânica do solo à penetração (RMSP). O escalonamento dos semivariogramas reduziu o tempo computacional de ajuste dos modelos, não apresentando diferenças no comportamento e amplitude da variabilidade espacial em relação aos semivariogramas não escalonados.

Análise espaço-temporal do uso da terra em parte do semi-árido cearense

A cobertura vegetal exerce papel imprescindível à proteção e conservação dos recursos naturais, principalmente no que diz respeito aos solos. Este estudo teve como objetivo avaliar e analisar a dimensão espacial e temporal da ação antrópica na cobertura vegetal de parte do semi-árido cearense, utilizando imagens LANDSAT TM-5, de 1985 e 1994, e técnicas de geoprocessamento, para verificar a hipótese de que a degradação ambiental vem sendo intensificada. Foram confeccionadas cartas de vegetação, uso da terra, solos e hidrografia, obtendo-se cartas de sobreposição, por meio das quais se constatou o aumento de áreas degradadas nas diferentes unidades fitoecológicas. No período de uma década, comprovou-se o processo progressivo da degradação nas áreas dos municípios de Independência, Pedra Branca, Mombaça e Tauá, tendo as áreas do município de Pedra Branca apresentado menor degradação. A unidade fitoecológica mais degradada, dentre as estudadas, foi a Caatinga Arbórea Aberta, desencadeando processos de degradação e transformação das unidades circunvizinhas. Grande parte da área foi atingida por processos de degradação ambiental, com forte pauperização da biodiversidade, acompanhados por um rebaixamento geral das formações vegetais.

Variabilidade temporal da resistência à penetração de um latossolo argiloso sob semeadura direta com rotação de culturas

O desenvolvimento radicular é afetado pela resistência mecânica do solo e altera o potencial de produção das culturas. Este trabalho teve como objetivo avaliar a resistência à penetração de um solo argiloso com distintos sistemas de cultura em semeadura direta. O experimento foi realizado no campo tecnológico da Cotrijuí, no município de Ijuí (RS), em um Latossolo Vermelho distroférrico típico com 0,68 kg kg-1 de argila, manejado sob semeadura direta, com quatro seqüências de culturas: sucessão soja/trigo, milho/aveia/milho + guandu/trigo/soja/trigo, guandu/trigo/soja/trigo/soja/aveia e crotalária/trigo/soja/aveia/milho/trigo. A resistência à penetração (RP), a umidade e a densidade do solo foram avaliadas em distintas épocas e profundidades. Em todos os sistemas de culturas no Latossolo argiloso com semeadura direta, o maior estado de compactação foi verificado na camada em torno de 0,1 m de profundidade e o menor na camada até 0,07 m. A RP teve grande variação temporal e foi associada à variação do teor de água para cada condição de densidade do solo ou estado de compactação. Durante o ciclo das culturas, valores de RP restritivos ao crescimento das plantas foram atingidos na camada de cerca de 0,03 a 0,23 m de profundidade, quando o teor de água do solo variou de 0,14 a 0,28 kg kg-1. O efeito de plantas de cobertura de estação quente, com sistema radicular abundante e formador de poros biológicos, na redução da resistência mecânica do solo à penetração não foi observado no tempo estudado.

Multisensory Integration and Perceptual Enhancement

We perceive our environment through multiple sensory channels. Nonetheless, research has traditionally focused on the investigation of sensory processing within single modalities. Thus, investigating how our brain integrates multisensory information is of crucial importance for understanding how organisms cope with a constantly changing and dynamic environment. During my thesis I have investigated how multisensory events impact our perception and brain responses, either when auditory-visual stimuli were presented simultaneously or how multisensory events at one point in time impact later unisensory processing. In "Looming signals reveal synergistic principles of multisensory integration" (Cappe, Thelen et al., 2012) we investigated the neuronal substrates involved in motion detection in depth under multisensory vs. unisensory conditions. We have shown that congruent auditory-visual looming (i.e. approaching) signals are preferentially integrated by the brain. Further, we show that early effects under these conditions are relevant for behavior, effectively speeding up responses to these combined stimulus presentations. In "Electrical neuroimaging of memory discrimination based on single-trial multisensory learning" (Thelen et al., 2012), we investigated the behavioral impact of single encounters with meaningless auditory-visual object parings upon subsequent visual object recognition. In addition to showing that these encounters lead to impaired recognition accuracy upon repeated visual presentations, we have shown that the brain discriminates images as soon as ~100ms post-stimulus onset according to the initial encounter context. In "Single-trial multisensory memories affect later visual and auditory object recognition" (Thelen et al., in review) we have addressed whether auditory object recognition is affected by single-trial multisensory memories, and whether recognition accuracy of sounds was similarly affected by the initial encounter context as visual objects. We found that this is in fact the case. We propose that a common underlying brain network is differentially involved during encoding and retrieval of images and sounds based on our behavioral findings. - Nous percevons l'environnement qui nous entoure à l'aide de plusieurs organes sensoriels. Antérieurement, la recherche sur la perception s'est focalisée sur l'étude des systèmes sensoriels indépendamment les uns des autres. Cependant, l'étude des processus cérébraux qui soutiennent l'intégration de l'information multisensorielle est d'une importance cruciale pour comprendre comment notre cerveau travail en réponse à un monde dynamique en perpétuel changement. Pendant ma thèse, j'ai ainsi étudié comment des événements multisensoriels impactent notre perception immédiate et/ou ultérieure et comment ils sont traités par notre cerveau. Dans l'étude " Looming signals reveal synergistic principles of multisensory integration" (Cappe, Thelen et al., 2012), nous nous sommes intéressés aux processus neuronaux impliqués dans la détection de mouvements à l'aide de l'utilisation de stimuli audio-visuels seuls ou combinés. Nos résultats ont montré que notre cerveau intègre de manière préférentielle des stimuli audio-visuels combinés s'approchant de l'observateur. De plus, nous avons montré que des effets précoces, observés au niveau de la réponse cérébrale, influencent notre comportement, en accélérant la détection de ces stimuli. Dans l'étude "Electrical neuroimaging of memory discrimination based on single-trial multisensory learning" (Thelen et al., 2012), nous nous sommes intéressés à l'impact qu'a la présentation d'un stimulus audio-visuel sur l'exactitude de reconnaissance d'une image. Nous avons étudié comment la présentation d'une combinaison audio-visuelle sans signification, impacte, au niveau comportementale et cérébral, sur la reconnaissance ultérieure de l'image. Les résultats ont montré que l'exactitude de la reconnaissance d'images, présentées dans le passé, avec un son sans signification, est inférieure à celle obtenue dans le cas d'images présentées seules. De plus, notre cerveau différencie ces deux types de stimuli très tôt dans le traitement d'images. Dans l'étude "Single-trial multisensory memories affect later visual and auditory object recognition" (Thelen et al., in review), nous nous sommes posés la question si l'exactitude de ia reconnaissance de sons était affectée de manière semblable par la présentation d'événements multisensoriels passés. Ceci a été vérifié par nos résultats. Nous avons proposé que cette similitude puisse être expliquée par le recrutement différentiel d'un réseau neuronal commun.