Temporal overlap and co-occurrence in a guild of sub-tropical tephritid fruit flies

Studies of community assembly have emphasized snapshot comparisons of spatially replicated samples from natural assemblages. Agro-ecosystems are characterized by relatively little habitat heterogeneity and no dispersal barriers for actively flying insects. Therefore, dynamic patterns of species segregation and aggregation are more likely to reflect the direct or indirect effects of species interactions. We studied the temporal organization of a guild of 21 congeneric species of Anastrepha that colonized fruit orchards in Monte Alegre do Sul, São Paulo, Brazil. This assemblage also included the introduced Mediterranean fruit fly Ceratitis capitata. One hundred six consecutive weekly censuses (11 Jan 2002-16 Jan 2004) of flies in guava, loquat, and peach orchards revealed a pattern of minimum abundance during the coldest months of each year (June and July) and a maximum abundance during periods of flowering and fruit ripening. Overall, phenological overlap was greater than expected by chance. However, conditioned on the pattern of seasonal abundances, temporal occurrence and abundance matrices exhibited patterns of significant species segregation and anti-nestedness. In each year, the 3 orchards contained a small number of species pairs that exhibited statistically significant temporal segregation or aggregation. Most aggregated and segregated pairs reflected seasonal shifts in species presences that were not related to variation in air temperature. Most of the significant pairwise associations involved C. capitata: 8 of the 11 segregated pairs and 2 of the 7 aggregated pairs. These results suggest that species interactions between introduced and native species can be an important determinant of species associations in agro-ecosystems

Bibliometric analysis of themes competitive intelligence, knowledge management and organizational knowledge in Institutional Repository University of Brasília

Trata da análise dos temas Inteligência Competitiva (IC), Gestão do Conhecimento (GC) e Conhecimento Organizacional (CO), no Repositório Institucional da Universidade da Brasília (RIUnB), que está disponível em acesso aberto desde setembro de 2008. O objetivo é verificar a produção científica sobre as áreas de pesquisa, a partir dos documentos que constam no RIUnB. O método de trabalho consistiu nos estudos bibliométricos, a fim de se inteirar sobre a produção de trabalhos referentes ao conhecimento resultante do desenvolvimento de pesquisas no âmbito institucional, para conhecer a comunidade. Os resultados apontam para um crescimento notório desses temas na ciência da informação, com perspectiva de crescimento em outras áreas: administração, engenharia elétrica, educação e gestão social e trabalho, demonstrando sua potencial interdisciplinaridade; houve maior concentração de publicação nos temas gestão do conhecimento, conhecimento organizacional e inteligência competitiva, respectivamente, e existe uma concentração dessas publicações em três pesquisadores na comunidade da Faculdade de Ciência da Informação (FCI). Conclui-se que os temas são mais frequentes na área de ciência da informação, entretanto, nota-se o seu aparecimento em outras áreas do conhecimento, na UnB: administração, engenharia elétrica, educação e gestão social e do trabalho. Esses dados podem revelar uma tendência de consolidação dos temas de pesquisa em outras áreas. ________________________________________________________________________________________ ABSTRACTThis analysis of topics Competitive Intelligence (CI), Knowledge Management (KM) and Organizational Knowledge (CO) in the Institutional Repository of the University of Brasília (RIUnB) which is available in open access since September 2008. The aim is to check the scientific literature on the research areas from the documents listed in RIUnB. The working method consisted in bibliometric studies, in order to learn about the production of works relating to knowledge resulting from research development at the institutional level to know the community. The results indicate a remarkable growth of these themes in information science, with growth prospects in other areas: administration, electrical engineering, management and education and social work, demonstrating its potential interdisciplinarity, there was a higher concentration of publishing on issues of knowledge management, organizational knowledge and competitive intelligence, respectively, and there is a concentration of such publications in three community researchers in the Faculty of Information Science (FCI). We conclude that the issues are more frequent in the area of information science, however, note its appearance in other areas of knowledge in UNB: administration, electrical engineering, education and social management and labor. These data may reveal a trend of consolidation of research topics in other areas

Heterotic-Type II duality in the hypermultiplet sector

We revisit the duality between heterotic string theory compactified on K3 x T^2 and type IIA compactified on a Calabi-Yau threefold X in the hypermultiplet sector. We derive an explicit map between the field variables of the respective moduli spaces at the level of the classical effective actions. We determine the parametrization of the K3 moduli space consistent with the Ferrara-Sabharwal form. From the expression of the holomorphic prepotential we are led to conjecture that both X and its mirror must be K3 fibrations in order for the type IIA theory to have an heterotic dual. We then focus on the region of the moduli space where the metric is expressed in terms of a prepotential on both sides of the duality. Applying the duality we derive the heterotic hypermultiplet metric for a gauge bundle which is reduced to 24 point-like instantons. This result is confirmed by using the duality between the heterotic theory on T^3 and M-theory on K3. We finally study the hyper-Kaehler metric on the moduli space of an SU(2) bundle on K3.Comment: 27 pages; references added, typos correcte

Inference of gene regulatory networks from time series by Tsallis entropy

Background: The inference of gene regulatory networks (GRNs) from large-scale expression profiles is one of the most challenging problems of Systems Biology nowadays. Many techniques and models have been proposed for this task. However, it is not generally possible to recover the original topology with great accuracy, mainly due to the short time series data in face of the high complexity of the networks and the intrinsic noise of the expression measurements. In order to improve the accuracy of GRNs inference methods based on entropy (mutual information), a new criterion function is here proposed. Results: In this paper we introduce the use of generalized entropy proposed by Tsallis, for the inference of GRNs from time series expression profiles. The inference process is based on a feature selection approach and the conditional entropy is applied as criterion function. In order to assess the proposed methodology, the algorithm is applied to recover the network topology from temporal expressions generated by an artificial gene network (AGN) model as well as from the DREAM challenge. The adopted AGN is based on theoretical models of complex networks and its gene transference function is obtained from random drawing on the set of possible Boolean functions, thus creating its dynamics. On the other hand, DREAM time series data presents variation of network size and its topologies are based on real networks. The dynamics are generated by continuous differential equations with noise and perturbation. By adopting both data sources, it is possible to estimate the average quality of the inference with respect to different network topologies, transfer functions and network sizes. Conclusions: A remarkable improvement of accuracy was observed in the experimental results by reducing the number of false connections in the inferred topology by the non-Shannon entropy. The obtained best free parameter of the Tsallis entropy was on average in the range 2.5 <= q <= 3.5 (hence, subextensive entropy), which opens new perspectives for GRNs inference methods based on information theory and for investigation of the nonextensivity of such networks. The inference algorithm and criterion function proposed here were implemented and included in the DimReduction software, which is freely available at http://sourceforge.net/projects/dimreduction and http://code.google.com/p/dimreduction/.Fundacao de Amparo e Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Coordenacao de Aperfeicofamento de Pessoal de Nivel Superior (CAPES)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq

Radiomic analysis of MRI to Predict Sustained Complete Response after Radiofrequency Ablation in Patients with Hepatocellular Carcinoma - A Pilot Study

OBJECTIVES: To investigate whether quantitative textural features, extracted from pretreatment MRI, can predict sustained complete response to radiofrequency ablation (RFA) in patients with hepatocellular carcinoma (HCC). METHODS: In this IRB-approved study, patients were selected from a maintained six-year database of consecutive patients who underwent both pretreatment MRI imaging with a probable or definitive imaging diagnosis of HCC (LI-RADS 4 or 5) and loco-regional treatment with RFA. An experienced radiologist manually segmented the hepatic nodules in MRI arterial and equilibrium phases to obtain the volume of interest (VOI) for extraction of 107 quantitative textural features, including shape and first- and second-order features. Statistical analysis was performed to evaluate associations between textural features and complete response. RESULTS: The study consisted of 34 patients with 51 treated hepatic nodules. Sustained complete response was achieved by 6 patients (4 with single nodule and 2 with multiple nodules). Of the 107 features from the arterial and equilibrium phases, 20 (18%) and 25 (23%) achieved AUC &gt;0.7, respectively. The three best performing features were found in the equilibrium phase: Dependence Non-Uniformity Normalized and Dependence Variance (both GLDM class, with AUC of 0.78 and 0.76, respectively) and Maximum Probability (GLCM class, AUC of 0.76). CONCLUSIONS: This pilot study demonstrates that a radiomic analysis of pre-treatment MRI might be useful in identifying patients with HCC who are most likely to have a sustained complete response to RFA. Second-order features (GLDM and GLCM) extracted from equilibrium phase obtained highest discriminatory performance

LALINET: The First Latin American–Born Regional Atmospheric Observational Network

Sustained and coordinated efforts of lidar teams in Latin America at the beginning of the 21st century have built LALINET (Latin American Lidar NETwork), the only observational network in Latin America created by the agreement and commitment of Latin American scientists. They worked with limited funding but an abundance of enthusiasm and commitment toward their joint goal. Before LALINET, there were a few pioneering lidar stations operating in Latin America, described briefly here. Bi-annual Latin American Lidar Workshops, held from 2001 to the present, supported both the development of the regional lidar community and LALINET. At those meetings, lidar researchers from Latin America meet to conduct regular scientific and technical exchanges among themselves and with experts from the rest of the world. Regional and international scientific cooperation has played an important role for the development of both the individual teams and the network. The current LALINET status and activities are described, emphasizing the processes of standardization of the measurements, methodologies, calibration protocols, and retrieval algorithms. Failures and successes achieved in the buildup of LALINET are presented. In addition, the first LALINET joint measurement campaign and a set of aerosol extinction profile measurements obtained from the aerosol plume produced by the Calbuco volcano eruption on April 22, 2015, are described and discussed.Fil: Antuña Marrero, Juan Carlos. Centro Meteorológico de Camagüey; CubaFil: Landulfo, Eduardo. Instituto de Pesquisas Energéticas e Nucleares; BrasilFil: Estevan, René. Centro Meteorológico de Camagüey; CubaFil: Barja, Boris. Centro Meteorológico de Camagüey; Cuba. Universidade de Sao Paulo; BrasilFil: Robock, Alan. State University of New Jersey; Estados UnidosFil: Wolfram, Elian Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; ArgentinaFil: Ristori, Pablo Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; ArgentinaFil: Clemesha, Barclay. Upper Atmosphere Research Group; BrasilFil: Zaratti, Francesco. Universidad Mayor de San Andrés; BoliviaFil: Forno, Ricardo. Universidad Mayor de San Andrés; BoliviaFil: Armandillo, Errico. ESTEC; Países BajosFil: Bastidas, Álvaro E.. Universidad Nacional de Colombia. Sede Medellin; ColombiaFil: de Frutos Baraja, Ángel Máximo. Universidad de Valladolid; EspañaFil: Whiteman, David N.. National Aeronautics and Space Administration; Estados UnidosFil: Quel, Eduardo Jaime. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; ArgentinaFil: Barbosa, Henrique M. J.. Universidade de Sao Paulo; BrasilFil: Lopes, Fabio. Comissao Nacional de Energia Nuclear. Centro de Lasers e Aplicacoes. Instituto de Pesquisas Energeticas e Nucleares.; BrasilFil: Montilla-Rosero, Elena. Universidad de Concepción; Chile. Universidad Escuela de Administración, Finanzas e Instituto Tecnológico; ColombiaFil: Guerrero Rascado, Juan L.. Comissao Nacional de Energia Nuclear. Centro de Lasers e Aplicacoes. Instituto de Pesquisas Energeticas e Nucleares.; Brasil. Universidad de Granada; Españ