422 research outputs found

    Balance demogrĂĄfico

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    Production and Persistence of a Native Pasture-\u3cem\u3eArachis pintoi\u3c/em\u3e Association in the Humid Tropics of Mexico

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    Arachis pintoi (Ap) is a highly persistent legume. This study aimed at: (i) determining if introducing Ap CIAT 17434 into a NG pasture affected its standing dry matter (SDM) and botanical composition (BC, %) and (ii) verifying if Ap would be as persistent as it is with introduced grasses (IG)

    Diversity and Abundance of Hymenopterous Parasitoids Associated with Anastrepha fraterculus (Diptera: Tephritidae) in Native and Exotic Host Plants in Misiones, Northeastern Argentina

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    Some Major host species used by the tephritid fruit flies Anastrepha fraterculus (Wiede-mann) and Ceratitis capitata (Wiedemann), including Acca sellowiana (O. Berg) Burret, Campomanesia xanthocarpa O. Berg, Psidium guajava L., Prunus persica (L.) Batsch, Eriobotrya japonica (Thunb.) Lindl., Citrus reticulata Blanco var. Murcott, C. aurantium L., C. paradisi Macfadyen var. Dalan Dan, and C. paradisi var. Sudashi, were sampled for fruit fly larvae between Feb and Dec 2000 in the northernmost section of the Paranaense forest, in the Province of Misiones, NE Argentina. Both A. fraterculus and C. capitata were obtained from these host plant species, with A. fraterculus accounting for 93% of all tephritid puparia identified. Ten species of larval-pupal parasitoids were recovered from A. fraterculus; Doryctobracon areolatus (Szépligeti), D. brasiliensis (Szépligeti), Utetes anastrephae (Viereck), Opius bellus (Gahan), Diachasmimorpha longicaudata (Ashmead) (Opiinae, raconidae), Odontosema anastrephae Borgmeier, Lopheucoila anastrephae (Rohwer), Aganaspis pelleranoi (BrÚthes) (Eucoilinae, Figitidae), Asobara anastrephae (Muessebeck) (Alyssinae, Braconidae), and Aceratoneuromyia indica (Silvestri) (Tetrastichinae, Eulophidae). All these parasitoids, with the exception of D. longicaudata and A. indica, are native to the Neotropical region. No parasitoids were recovered from C. capitata puparia. Asobara anastrephae and O. anastrephae are newly recorded in Argentina, whereas D. brasiliensis, U. anastrephae, and L. anastrephae are newly reported in Misiones. The eucoiline A. pelleranoi wasthe most abundant parasitoid species. Acca sellowiana and P. guajava harbored the highest parasitoid abundance and diversity.Fil: Schliserman, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Catamarca. Universidad Nacional de Catamarca. Centro de Investigaciones y Transferencia de Catamarca; ArgentinaFil: Ovruski Alderete, Sergio Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumån. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Decoll, Olga. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Misiones; ArgentinaFil: Wharton, Robert. Texas A&M University; Estados Unido

    Gause's exclusion principle revisited: artificial modified species and competition

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    Gause's principle of competition between two species is studied when one of them is sterile. We study the condition for total extinction in the niche, namely, when the sterile population exterminates the native one by an optimal use of resources. A mathematical Lotka-Volterra non linear model of interaction between a native and sterile species is proposed. The condition for total extinction is related to the initial number MoM_{o} of sterile individuals released in the niche. In fact, the existence of a critical sterile-population value McM_{c} is conjectured from numerical analysis and an analytical estimation is found. When spatial diffusion (migration) is considered a critical size territory is found and, for small territory, total extinction exist in any case. This work is motived by the extermination agriculture problem of fruit flies in our region.Comment: 11 pages. Published in Jour.Phys.A Math.Gen. 33, 4877 (2000

    Psychometric properties of the Catalan version of the Trait Emotional Intelligence (TEIQue): Comparison between Catalan and English data

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    The present study compared the psychometric properties of the Trait Emotional Intelligence Questionnaire (TEIQue) in Catalan and UK samples. The results showed similar means and standard deviations in the facets scoring higher in both languages, except for Adaptability (d: − 0.50) and emotion management (d: − 0.37). The alpha reliabilities of the TEIQue facets were similar and acceptable in both samples. The TEIQue alpha was 0.95 and 0.90 in Catalonia and the UK, respectively. All TEIQue facets were highly correlated in both samples, suggesting a coherent construct. The factor structure was investigated through exploratory (EFA) and confirmatory factor analysis (CFA) for 13 and 15 facets respectively. The four-factor theoretical structure was satisfactorily replicated using orthogonal rotation for 13 and 15 facets. Factor congruency coefficients were at, or above, 0.98 for both languages and both solutions (13 and 15 facets). As expected, CFA analyses of the simple structures of the three models yielded unsatisfactory fit indices, although these improved considerably after incorporating secondary loadings and correlated error terms. The cross-cultural stability of the instrument was supported by multigroup analyses. The relationships between TEIQue factors and facets were the same in both countries. The TEIQue psychometric properties were similar and robust in both samples

    Modeling general, specific, and method variance in personality measures: Results for ZKA-PQ and NEO-PI-R

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    Reprinted by permission of SAGE PublicationsContemporary models of personality assume a hierarchical structure in which broader traits contain narrower traits. Individual differences in response styles also constitute a source of score variance. In this study, the bifactor model is applied to separate these sources of variance for personality subscores. The procedure is illustrated using data for two personality inventories—NEO Personality Inventory–Revised and Zuckerman–Kuhlman–Aluja Personality Questionnaire. The inclusion of the acquiescence method factor generally improved the fit to acceptable levels for the Zuckerman–Kuhlman–Aluja Personality Questionnaire, but not for the NEO Personality Inventory–Revised. This effect was higher in subscales where the number of direct and reverse items is not balanced. Loadings on the specific factors were usually smaller than the loadings on the general factor. In some cases, part of the variance was due to domains being different from the main one. This information is of particular interest to researchers as they can identify which subscale scores have more potential to increase predictive validit

    Cross-Cultural Measurement Invariance in the Personality Inventory for DSM-5

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    The validity of cross-cultural comparisons of test scores requires that scores have the same meaning across cultures, which is usually tested by checking the invariance of the measurement model across groups. In the last decade, a large number of studies were conducted to verify the equivalence across cultures of the dimensional Alternative Model of Personality Disorders (DSM-5 Section III). These studies have provided information on configural invariance (i.e., the facets that compose the domains are the same) and metric invariance (i.e., facet-domain relationships are equal across groups), but not on the stricter scalar invariance (i.e., the baseline levels of the facets are the same), which is a prerequisite for meaningfully comparing group means. The present study aims to address this gap. The Personality Inventory for DSM-5 (PID-5) was administered to five samples differing on country and language (Belgium, Catalonia, France, Spain, and Switzerland), with a total of 4,380 participants. Configural and metric invariance were supported, denoting that the model structure was stable across samples. Partial scalar invariance was supported, being minimal the influence of non-invariant facets. This allowed cross-cultural mean comparisons. Results are discussed in light of the sample composition and a possible impact of culture on development of psychopathologyPreparation of this manuscript was supported by Grant PSI2017–85022-P (Ministerio de Ciencia, Innovacion ® y Universidades, Spain) and the UAM-IIC Chair "Psychometric Models and Applications

    Performance of Dual-Purpose Cows on a Native Pasture-\u3ci\u3eArachis pintoi\u3c/i\u3e Association in the Humid Tropics of Mexico

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    Native grasslands (NG) are the main feed supply of dual-purpose (DP) cows of the Mexican humid tropics. NG comprise about 85% of Paspalum, Axonopus and Cynodon species, about 5% of native legumes, mainly of Desmodium, and the remaining 10% are narrow and broad leafed weeds. Arachis pintoi (AP) is a persistent grazing tolerant tropical legume. In association with sown grasses, it has improved dry matter (DM) yield, nutritive quality of forage, and milk yield up to 9 kg/cow/day (GonzĂĄlez et al., 1996). The objective was to determine if productive performance of DP cows could be improved by the introduction of AP into NG grassland

    The Temporal Pattern of Mating Behavior of the Fruit Fly, Anastrepha zenildae in the Laboratory

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    The state of Rio Grande do Norte is an important fruit-producing and exporting area in northeastern Brazil. The success of this industry depends on fruit fly population control, especially in fly-free exporting zones. However, many fruits are not exported because of quarantine restrictions imposed by importing countries. A survey in the state has detected a considerable increase of the fruit fly, Anastrepha zenildae Zucchi (Diptera: Tephritidae), probably a result of the introduction of irrigated guava orchards that make fruit available all year. Knowledge of the sexual behavior of Tephritidae has great importance to pest control programs, particularly those that employ the Sterile Insect Technique. In order to characterize the reproductive behavior of A. zenildae, 32 individuals (16 males; 16 females) in each of six generations were submitted to an artificial 12:12 L:D cycle (750: < 1 lux, lights on 07:00–19:00) and observed over their lifetimes. The courtship and copulation occurred in leks and the episodes varied with the time of day, courtship being most frequent between Zeitgeber time (ZT) 3 and ZT 7, peaking at ZT 5–6. Copulations occurred between ZT 2 and ZT 8, with a higher frequency between ZT 5–7 and a peak at ZT 6. Mean duration was 0.28 ± 0.03 min/male (range: 5–163 min). Males in the leks attempted to copulate mainly between ZT 3 and ZT 7 with a peak at ZT 6, and males outside leks peaked at ZT 7. The different timing of sexual behaviors among related sympatric species, including A. zenildae, may contribute to species isolation
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