The O(α2^{2}) initial state QED corrections to e+^{+} e−^{-} →\rightarrow γ\gamma∗^{*} / Z0∗_{0}^{*}

We calculate the complete O($\alpha$$^{2}$) initial state radiation corrections to e$^{+}$ e$^{-}$ annihilation into a neutral vector boson in a direct analytic computation without any approximation. The corrections are represented in terms of iterated incomplete (elliptic) integrals over alphabets of square-root valued letters. Performing the limit s >> m$_{e}^{2}$, we find discrepancies with the earlier results of Ref. [1] and confirm results obtained in Ref. [2] where the effective method of massive operator matrix elements has been used, which works for all but the power corrections in m$_{e}^{2}$/s. In this way, we also confirm the validity of the factorization of massive partons in the Drell-Yan process to O($\alpha$$^{2}$). We add non logarithmic terms at O($\alpha$$^{2}$) which have not been considered in previous calculations. The final results in the limit s >> m$_{e}^{2}$ can be given in terms of Nielsen integrals

Validade e reprodutibilidade de receptores para o GPS em relação à distância percorrida Validez y reproducibilidad de receptores GPS en relación de la distancia recorrida

ResumenObjetivoEl presente estudio evaluó la validez y reproducibilidad de dos modelos de receptores para el Global Positioning System (GPS). La validez fue evaluada comparando la distancia registrada por los receptores con la distancia conocida de estos trayectos.MétodoSeis jóvenes tenistas (177,6±6,2cm; 76,6±3,2kg) recorrieron tres trayectos: 1) 100m en la pista de atletismo (número de “disparos” = 120); 2) 400m en la pista de atletismo (número de “disparos” = 60) y 3) 100m con cambios de dirección (número de “disparos” = 120), utilizando los equipos Garmin© Forerunner 405 y Polar© RS800.ResultadosEn los trayectos sin cambios de dirección (100 y 400m), a través de la ANOVA two way (distancia y velocidad) no se detectaron diferencias entre la distancia conocida y las distancias registradas por los receptores analizados (p>0,05). En el trayecto de 100m con cambios de dirección, se observaron diferencias entre la distancia conocida y las registradas tanto por el Polar© RS800 como por el Garmin© Forerunner 405 (p<0,05). También se verificó la diferencia en las distancias registradas por el Polar® RS800 y por el Garmin© Forerunner 405 para el trayecto realizado con cambios de dirección (p<0,05).ConclusiónA través de los datos, se puede afirmar que los receptores para GPS evaluados presentaron un nivel aceptable de precisión para distancias recorridas sin cambios de dirección, sin embargo, la precisión de estos equipos en trayectos con cambios de dirección fue limitada.AbstractObjectiveThe present study evaluated the reproducibility and validity of two models of receivers for the Global Positioning System (GPS). Validity was assessed by comparing the distance recorded by the GPS receivers with the known distance.MethodSix young players (177.6±6.2cm; 76.6±3.2kg) performed three routes with different characteristics: 1) 100m in the athletics track (number of “sprints” = 120); 2) 400m in the athletics track (number of “sprints” = 60) and 3) 100m with changes of direction (number of “sprints” = 120), using equipment Garmin© Forerunner 405 and Polar© RS800.ResultsRegarding linear routes (100 and 400m), no differences were detected using ANOVA two-way (distance and speed) between the known distance and distance recorded by GPS receivers analyzed (p>0.05). Regarding non-linear route of, significant differences were observed between the known distance and recorded distance by the GPS receivers (p<0.05). There was also a significant difference between the distance recorded by Polar© RS800 and Garmin© Forerunner 405 for the non-linear route (p<0.05). Analysis of the limits of agreement reinforces the limitation of equipment in relation to accuracy for the non-linear route.ConclusionThese data suggest that the GPS receivers evaluated showed acceptable level of accuracy for linear routes, however, the accuracy of such devices on non-linear routes was limited

Neoctangium travassosi (Digenea: Microscaphidiidae) in sea turtles from South America

ABSTRACT Sea turtles are endangered animals that present cosmopolitan distribution. Anthropic actions have been considered important causes for the reduction of sea turtle population, but natural aspects such as parasitism may also contribute to their decline. This study aimed to report the occurrence of parasites in stranded dead sea turtles found in an area known as Potiguar Basin, northeastern Brazil, from 2010 to 2019. They were identified and classified according to the carapace length. At post-mortem analyses all organs were examined, parasites collected and morphologically identified. Ecological parasitic indexes as prevalence (P), mean intensity (MI) and mean abundance (MA) were calculated. A total of 80 Chelonia mydas and 5 Eretmochelys imbricata were assessed. Neoctangium travassosi was detected in both species presenting P = 20%, MI = 4.19 and MA = 0.84 for C. mydas and P = 60%, MI = 1.67 and MA = 1.0 for E. imbricata. This is the first report of N. travassosi parasitizing E. imbricata in South America. Finally, the retrieval of these parasites is a warning regarding the need for further studies to assess the impact of this parasitism on the health and conservation of sea turtles

Structural assessment, toxicity, and increased antimicrobial activity

Scorpion venom is a rich source of biologically active components and various peptides with high-potential therapeutic use that have been characterized for their antimicrobial and antiproliferative activities. Stigmurin is a peptide identified from the Tityus stigmurus venom gland with high antibacterial and antiproliferative activities and low toxicity. Amino acid substitutions in peptides without a disulfide bridge sequence have been made with the aim of reducing their toxicity and increasing their biological activities. The purpose of this study was to evaluate the structural conformation and structural stability, as well as antimicrobial, antiproliferative, and hemolytic activities of two peptide analogs to Stigmurin, denominated StigA6 and StigA16. In silico analysis revealed the &alpha;-helix structure for both analog peptides, which was confirmed by circular dichroism. Data showed that the net charge and hydrophobic moment of the analog peptides were higher than those for Stigmurin, which can explain the increase in antimicrobial activity presented by them. Both analog peptides exhibited activity on cancerous cells similar to the native peptide; however, they were less toxic when tested on the normal cell line. These results reveal a potential biotechnological application of the analog peptides StigA6 and StigA16 as prototypes to new therapeutic agents.publishersversionpublishe

Climate seasonality limits leaf carbon assimilation and wood productivity in tropical forests

The seasonal climate drivers of the carbon cycle in tropical forests remain poorly known, although these forests account for more carbon assimilation and storage than any other terrestrial ecosystem. Based on a unique combination of seasonal pan-tropical data sets from 89 experimental sites (68 include aboveground wood productivity measurements and 35 litter productivity measurements), their associated canopy photosynthetic capacity (enhanced vegetation index, EVI) and climate, we ask how carbon assimilation and aboveground allocation are related to climate seasonality in tropical forests and how they interact in the seasonal carbon cycle. We found that canopy photosynthetic capacity seasonality responds positively to precipitation when rainfall is < 2000ĝ€-mmĝ€-yrĝ'1 (water-limited forests) and to radiation otherwise (light-limited forests). On the other hand, independent of climate limitations, wood productivity and litterfall are driven by seasonal variation in precipitation and evapotranspiration, respectively. Consequently, light-limited forests present an asynchronism between canopy photosynthetic capacity and wood productivity. First-order control by precipitation likely indicates a decrease in tropical forest productivity in a drier climate in water-limited forest, and in current light-limited forest with future rainfall < 2000ĝ€-mmĝ€-yrĝ'1. Author(s) 2016.Fil: Wagner, Fabien H.. Instituto Nacional de Pesquisas Espaciais; BrasilFil: Hérault, Bruno. Ecologie Des Forets de Guyane; BrasilFil: Bonal, Damien. Institut National de la Recherche Agronomique; FranciaFil: Stahl, Clment. Universiteit Antwerp; BélgicaFil: Anderson, Liana O.. National Center For Monitoring And Early Warning Of Natural Disasters; BrasilFil: Baker, Timothy R.. University Of Leeds; Reino UnidoFil: Sebastian Becker, Gabriel. Universidad de Hohenheim; AlemaniaFil: Beeckman, Hans. Royal Museum For Central Africa; BélgicaFil: Boanerges Souza, Danilo. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Cesar Botosso, Paulo. Ministerio da Agricultura Pecuaria e Abastecimento de Brasil. Empresa Brasileira de Pesquisa Agropecuaria; BrasilFil: Bowman, David M. J. S.. University of Tasmania; AustraliaFil: Bräuning, Achim. Universitat Erlangen-Nuremberg; AlemaniaFil: Brede, Benjamin. Wageningen University And Research Centre; Países BajosFil: Irving Brown, Foster. Universidade Federal Do Acre; BrasilFil: Julio Camarero, Jesus. Instituto Boliviano de Investigacion Forestal Bolivia; BoliviaFil: Camargo, Plnio Barbosa. Universidade de Sao Paulo; BrasilFil: Cardoso, Fernanda C.G.. Universidade Federal do Paraná; BrasilFil: Carvalho, Fabrcio Alvim. Universidade Federal de Juiz de Fora; BrasilFil: Castro, Wendeson. Universidade Federal Do Acre; BrasilFil: Koloski Chagas, Rubens. Universidade de Sao Paulo; BrasilFil: Chave, Jrome. Centre National de la Recherche Scientifique; FranciaFil: Chidumayo, Emmanuel N.. University Of Zambia; ZambiaFil: Clark, Deborah A.. University Of Missouri-st. Louis; Estados UnidosFil: Regina Capellotto Costa, Flavia. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Couralet, Camille. Royal Museum For Central Africa; BélgicaFil: Henrique Da Silva Mauricio, Paulo. Universidade Federal Do Acre; BrasilFil: Dalitz, Helmut. Universidad de Hohenheim; AlemaniaFil: Resende De Castro, Vinicius. Universidade Federal de Vicosa; BrasilFil: Milani, Jaanan Eloisa De Freitas. Universidade Federal do Paraná; BrasilFil: Roig Junent, Fidel Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla; Argentin