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Galls as a Disputed Resource for Female Parasitoid Wasps Contests
This is the final version of the article. It first appeared from Scientific Research Publishing via http://dx.doi.org/ 10.4236/ae.2015.33010We investigated how the parasitoid Torymus sp. (Hymenoptera: Torymidae) attacking galls of Schismatodiplosis lantanae (Diptera: Cecidomyiidae) on Lantana camara (Verbenaceae) behaves in the presence of a conspecific female competitor in the patch. Presence of a competitor greatly changed resident exploitation behavior. Wasps alone spent more time in gall exploitation behaviors (walk-antennate and probe) and in post-oviposition behaviors (stationary and groom), and when intruders were present they spent more time walking. The attack strategy was trough threatening: raising wings and pointing the antennae towards the opponent. Different from theoretical expectations, residents were not always the attacker. Number of galls in the patch and female wasp size did not affect contest outcomes, although gall exploitation time and time on leaf were significant factors for the probability of having attacks. Overall, the study highlights the fact that intruder interest in the host was the main cause of contests and also this is a unique report both in terms of the target species and the nature of the disputed resource, a gall-inducer inside a singular spatial unit, the gall.We thank all anonymous referees, Marlène Goubault, Paula Beatriz de Araujo, Geraldo Luiz Gonçalves Soares and Luiz Ernesto Costa Schmidt for suggestions and comments. Simone Mundstock Jahnke and Valmir Antonio Costa for helping in wasp identification. This study was supported by CAPES
Effects of cholestyramine and lovastatin upon plasma lipids and egg yolk cholesterol levels of laying hens
The purpose of this study was to evaluate the effect of cholestyramine and lovastatin, lipid-lowering agents, upon egg quality, reproductive performance, plasma lipids and egg yolk cholesterol levels of Shaver laying hens. Twenty-six-weeks-old hens were fed basal diet without animal products containing 0.2% cholestyramine (COL1), 0.3% cholestyramine (COL2) or 0.005% lovastatin (LOV) for 6 weeks. It was observed that the supplementation of the drugs did not impair albumen and shell quality. Hen performance was not adversely affected, with the exception of the significant reduction (p < 0.05) in egg weights. No significant changes were observed on plasma lipids, and egg yolk cholesterol remained unchanged with the addition of the drugs.O presente trabalho teve por objetivo avaliar os efeitos da colestiramina e da lovastatina, drogas hipolipemizantes, sobre a qualidade do ovo, desempenho das aves, teores de lípides plasmáticos e de colesterol na gema do ovo de galinhas poedeiras Shaver. Aves com 26 semanas de idade receberam como alimentação dieta formulada sem ingredientes de origem animal (COM) acrescida de colestiramina a 0,2% (COL1) e 0,3% (COL2) e lovastatina a 0,005% (LOV) durante 6 semanas. A adição das drogas não prejudicou a qualidade da casca e do albúmen dos ovos. De um modo geral, o desempenho produtivo das aves não foi afetado, com exceção da redução observada no peso médio dos ovos. Não foram observadas mudanças nos teores de lípides plasmáticos das aves e a concentração de colesterol na gema permaneceu inalterada mediante a adição das drogas
First Record of the Dolichoderine Ant Genus Gracilidris Wild & Cuezzo (Hymenoptera: Formicidae) from Southern Brazil
ABSTRACT - The dolichoderine ant species Gracilidris pombero, sole representative of the genus, is recorded for the first time in southern Brazil. Until now, the species was known only for the open fields of the South American dry diagonal and for a single locality in the Colombian Amazon. The specimens reported here were collected with pitfall traps in grasslands of the Pampa biome, Rio Grande do Sul state, Brazil. This record represents the southernmost occurrence for the genus, extending its distribution in approximately 450 km to the south in the Neotropics and in almost 1,150 km to the south in Brazil
On the development of a technological solution for long-term preservation of the commercial qualities in live oysters
The Pacific Oyster has adapted well to the southern Brazilian environmental conditions,
where the combination of factors allows harvest in less than eight months. Although
convenient for most of the year, it is during summer that water temperature can exceed 30
ºC, a summer condition that leads to high mortality rates. According to the literature, if spawning
is not triggered, a substantial reduction in mortality can be achieved. Studies previously
presented at CYTEF 2020 showed that confining oysters at temperatures close to those of
basal metabolism can inhibit the effects of gametogenesis. Further research was conducted
in order to verify the possible outcomes of long term confinement of late autumn harvested
oysters, presenting high glycogen reserves. This article reports the experimental results of
those tests, regarding the preservation of quality attributes and the reduction of mortality rates,
when confining oysters under temperatures similar to those of basal metabolism regime
Public park policies and Carsharing Systems / Políticas de estacionamento público para sistemas de compartilhamento de veículos
This article addresses the topic of car sharing and public policies related to the regulation of parking areas for the system. The article aims to identify the practices that contribute to a better performance of sharing systems and the legal frameworks of the metropolitan region of Rio de Janeiro that can regulate their implementation..
Estudo comparativo de duas linhagens de aves especializadas para produção de "broilers". I - Fertilidade e eclodibilidade relacionadas ao peso dos ovos
During the course of this study, 1,456 eggs laid by two strains — “A ” and “B” — of chicken for meat production were classified in three egg weight groups — I (51 — 55 g), II (56 — 60 g), III (61 — 65 g) — , in order to determine fertility and hatchability. The fertility was estimated by candling on the eighteenth day of incubation. a — Fertility The analysis of variance of fertility showed that the difference between the two strains (A = 88.1% and B = 88.8%) was not significant. With respect the egg weight groups, higher level of fertility occurred in class II (89.3%) while in group I and III, were obtained 87.8% and 88.1%, respectively. On the other hand, the correlation demonstrated statistical significance (r = + 0,56) between fertility and individual egg weight. b — Hatchability Percent hatch of good chicks from fertile eggs were 93.8% and 89.3% for strains “A ” and “B” , respectively. This difference, statistically significant, indicated therefore that the strain “B” produced more “cull chicks” — 6.1% — than strain “A ” (2.7%). In relation to egg weight groups, the higher hatchability ocurred in the class III (93.7%). Aside from, it seems that group II (56 — 60 g) shows a strong tendency to produce higher hatch of “ cull chicks” (6.9%) in relation to others egg weight groups (I = 3.9% and III = 2.7%). It appears also that incubator eggs localization did not affect the hatchability.No estudo em tela, 1456 ovos oriundos de duas linhagens de aves, aqui denominadas “A ” e “B” , especializadas para produção de “broilers” , foram distribuídos em três classes de acôrdo com o pêso — I (51 a 55g), II (56 a 60g) e III (61 a 65g) — e incubados com a finalidade de estimarem-se os índices de fertilidade e eclodibilidade. a — Fertilidade Quanto aos índices percentuais de fertilidade, registraram-se resultados pràticamente superponíveis ou seja, de 88,1 % e 88,8% para as linhagens “A ” e “B” , respectivamente. Tal diferença, como era de se esperar, foi julgada não significante estatisticamente. Ao estabelecerem-se comparações entre graus de fertilidade e classes de ovos, abstração feita às linhagens, anotou-se o índice percentual de 89,3% para a classe II, ligeiramente superior aos obtidos nas classes I (87,8%) e III (88,19%). Por outro lado, a correlação verificada entre índices de fertilidade e pêso individual dos ovos, revelou-se estatisticamente significante (r = + 0,56). b — Eclodibilidade Os índices de eclosão, estimados em relação aos ovos férteis, foram de 93,8% e 89,3% de nascimentos de pintos viáveis, respectivamente, para as linhagens “ A” e “B” . Tal diferença, de significado estatístico, destacou que a linhagem “B” produziu maior percentual de refugos — 6,1% — quando comparada à linhagem “A” cujo índice de nascimento de pintos não viáveis, atingiu a cifra de 2,7%. No confronto entre eclodibilidade e classes de ovos, sem levar em conta as linhagens, a porcentagem mais elevada foi consignada na classe III (93,7%). O simples exame dos resultados sugere que os ovos da classe II estariam associados ao mais acentuado índice de nascimento de pintos não viáveis — 6,9% — se comparados aos verificados nas classes I (3 ,9 %) e III (2,7%). A localização das bandejas na incubadora não exerceu influência sôbre os índices de eclosão
Disorder drives cooperative folding in a multidomain protein
Many human proteins contain intrinsically disordered regions, and disorder in these proteins can be fundamental to their function - for example, facilitating transient but specific binding, promoting allostery, or allowing efficient posttranslational modification. SasG, a multidomain protein implicated in host colonization and biofilm formation in Staphylococcus aureus, provides another example of how disorder can play an important role. Approximately one-half of the domains in the extracellular repetitive region of SasG are intrinsically unfolded in isolation, but these E domains fold in the context of their neighboring folded G5 domains. We have previously shown that the intrinsic disorder of the E domains mediates long-range cooperativity between nonneighboring G5 domains, allowing SasG to form a long, rod-like, mechanically strong structure. Here, we show that the disorder of the E domains coupled with the remarkable stability of the interdomain interface result in cooperative folding kinetics across long distances. Formation of a small structural nucleus at one end of the molecule results in rapid structure formation over a distance of 10 nm, which is likely to be important for the maintenance of the structural integrity of SasG. Moreover, if this normal folding nucleus is disrupted by mutation, the interdomain interface is sufficiently stable to drive the folding of adjacent E and G5 domains along a parallel folding pathway, thus maintaining cooperative folding
Ground-Dwelling and Vegetation Ant Fauna in Southern Brazilian Grasslands
Non-forest ecosystems, as natural grasslands from Southern Brazil, are still neglected in conservation policies. Measuring their biodiversity is one of the main steps to generate management strategies for these habitats. This study aims to (i) describe grassland ant richness and composition in Rio Grande do Sul state, and (ii) compare ant communities sampled on the ground and in grassland vegetation, adding to our knowledge of habitat use patterns and vegetation associated species. Six sites were sampled, three belonging to the Pampa biome and three in highland region from the Atlantic Forest biome. Ant fauna was collected once per year in summer during four years in each site with pitfalls traps and sweeping nets. Overall, 29,812 ant individuals were sampled belonging to eight subfamilies, 30 genera e 106 species. The grasslands of Pampa accumulated 91 species and 45 exclusive species, while highland grasslands summed up 61 species and only 15 exclusive species. Species composition differs between biomes as well as between sampling methods. Ant communities sampled from vegetation represented a clear subset of the fauna sampled with pitfall traps, and indication analysis showed only two species associated with this stratum: Myrmelachista gallicola and Pseudomyrmex nr. flavidulus. This study highlights the importance of Southern Brazilian grasslands and the need for specific conservation strategies for the natural grasslands from each biome
Introducción: La institucionalización de los estudios académicos sobre la historia del esoterismo occidental en América del Sur: el Centro de Estudios sobre el Esoterismo Occidental de la UNASUR. Problemas y desafíos.
QUANTIFICAÇÃO DE GASES DE EFEITO ESTUFA EM ATERRO SANITÁRIO NO MUNICÍPIO DE CUIABÁ
A disposição do lixo no Brasil, onde o uso de “lixões” ainda é muito comum, é um dos graves problemas ambientais. A emissão de gases produzidos pela decomposição anaeróbia da matéria orgânica pode ser uma ameaça ao ambiente local causando danos à vegetação, gerando odores desagradáveis, oferecendo ainda riscos de explosão. Este estudo objetivou avaliar as emissões de dióxido de carbono (CO2) e metano (CH4) no Aterro Sanitário no Município de Cuiabá, utilizando câmaras estáticas. Avaliou três pontos de amostragem com diferentes tempos de deposição de resíduos. Os valores anuais de CO2 foram: no ponto A (deposição recente), 19,02 μg CO2 m-2 h-1; no ponto B (deposição intermediária), 4,36 μg CO2 m-2 h-1 e, no ponto C (deposição com maior tempo), 2,59 μg CO2 m-2 h-1. A concentração de CH4 no ponto A foi 3,89 μg CH4 m-2 h-1 e 0,12 e 0,25 μg CH4 m-2 h-1 nos pontos B e C, respectivamente. Os resultados de CO2 e CH4 tiveram comportamentos semelhantes, houve aumento das concentrações. O estudo concluiu que fluxo de gases é dependente do tempo de deposição de resíduos e que, de acordo com esse tempo de deposição, a compactação do solo atua como limitador na emissão de GEE. QUANTIFICATION OF GREENHOUSE GASES IN LANDFILL IN CUIABÁ CITYThe disposal of garbage in Brazil is one of the serious environmental problems where the use of "dumps" is still very common. The emission of gases produced by the anaerobic decomposition of organic matter can be a threat to the local environment, causing damage to vegetation, generating unpleasant odors, also offering risks of explosion. This study objective evaluated emissions of Carbon Dioxide (CO2) and Methane (CH4) in landfill in the Cuiabá city, using static chambers. Three sampling points under different waste deposition times were evaluated. The annual flow of CO2 at point A (recent deposition) was 19.02 μg CO2 m-2 h-1, at point B (intermediate), it was 4.36 μg CO2 m-2 h-1, and at point C (deposition with longer time) was 2.59 μg CO2 m-2 h-1. The concentration of CH4 at point A was 3.89 μg CH4 m-2 h- and 0.12 and 0.25 μg CH4 m-2 h-1 respectively at points B and C. The results of CO2 and CH4, have similar behavior, occurring increase of concentrations. It concluded that gas flow is dependent on the time of waste deposition, and according to the time of deposition, the soil compaction performances as a limiting factor in GHG emissions
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