Contrary effects of jasmonate treatment of two closely related plant species on attraction of and oviposition by a specialist herbivore

Elevated jasmonic acid (JA) concentrations in response to herbivory can induce wounded plants to produce defences against herbivores. In laboratory and field experiments we compared the effects of exogenous JA treatment to two closely related cabbage species on the host-searching and oviposition preference of the diamondback moth (DBM), Plutella xylostella. JA-treated Chinese cabbage (Brassica campestris) was less attractive than untreated Chinese cabbage to ovipositing DBM, while JA-treatment of common cabbage (B. oleracea) made plants more attractive than untreated controls for oviposition by this insect. Similar effects were observed when plants of the two species were damaged by DBM larvae. In the absence of insect-feeding, or JA application, Chinese cabbage is much more attractive to DBM than common cabbage. Inducible resistance therefore appears to occur in a more susceptible plant and induced susceptibility appears to occur in a more resistant plant, suggesting a possible balance mechanism between constitutive and inducible defences to a specialist herbivore.

Diel 'tuning' of coral metabolism: physiological responses to light cues

Hermatypic-zooxanthellate corals track the diel patterns of the main environmental parameters temperature, UV and visible light - by acclimation processes that include biochemical responses. The diel course of solar radiation is followed by photosynthesis rates and thereby elicits simultaneous changes in tissue oxygen tension due to the shift in photosynthesis/respiration balance. The recurrent patterns of sunlight are reflected in fluorescence yields, photosynthetic pigment content and activity of the two protective enzymes superoxide dismutase (SOD) and catalase (CAT), enzymes that are among the universal defenses against free radical damage in living tissue. All of these were investigated in three scleractinian corals: Favia favus, Plerogyra sinuosa and Goniopora lobata. The activity of SOD and CAT in the animal host followed the course of solar radiation, increased with the rates of photosynthetic oxygen production and was correlated with a decrease in the maximum quantum yield of photochemistry in Photosystem H (PSII) (Delta F'/F-m'). SOD and CAT activity in the symbiotic algae also exhibited a light intensity correlated pattern, albeit a less pronounced one. The observed rise of the free-radical-scavenger enzymes, with a time scale of minutes to several hours, is an important protective mechanism for the existence and remarkable success of the unique cnidarian-dinoflagellate associations, in which photosynthetic oxygen production takes place within animal cells. This represents a facet of the precarious act of balancing the photosynthetic production of oxygen by the algal symbionts with their destructive action on all living cells, especially those of the animal host.

Feeding preference and deterrence in rabbitfish Siganus fuscescens for the cyanobacterium Lyngbya majuscula in Moreton Bay, south-east Queensland, Australia

Rabbitfish Siganus fuscescens preferences for Lyngbya majuscula collected from three bloom locations in Moreton Bay, Queensland, Australia, were tested along with a range of local plant species in the laboratory. Consumption of L. majuscula by fish did not differ between wild and captive-bred fish (P = 0.152) but did differ between bloom location (P = 0.039). No relationship was found between consumption rates and lyngbyatoxin-a concentration (r(2) = 0.035, P = 0.814). No correlation existed between C : N and proportion of food consumed when all food types were analysed statistically, whereas a clear correlation was observed when L. majuscula was removed from the calculations. In simulated bloom conditions, fish avoided ingestion of L. majuscula by feeding through gaps in the L. majuscula coverage. Both wild and captive-bred S. fuscescens showed a distinct feeding pattern in 10 day no-choice feeding assays, with less L. majuscula being consumed than the preferred red alga Acanthophora spicifera. Lyngbya majuscula however, was consumed in equal quantities to A. spicifera by wild S. fuscescens when lyngbyatoxin-a was not detectable. Wild fish probably do not preferentially feed on L. majuscula when secondary metabolites are present and are not severely impacted by large L. majuscula blooms in Moreton Bay. Furthermore, poor feeding performance in both captive-bred and wild S. fuscescens suggests that they would exert little pressure as a top-down control agent of toxic L. majuscula blooms within Moreton Bay. (c) 2006 The Fisheries Society of the British Isles.

Substantial changes in the genetic basis of tadpole morphology of Rana lessonae in the presence of predators

Predator-induced morphological plasticity is a model system for investigating phenotypic plasticity in an ecological context. We investigated the genetic basis of the predator-induced plasticity in Rana lessonae by determining the pattern of genetic covariation of three morphological traits that were found to be induced in a predatory environment. Body size decreased and tail dimensions increased when reared in the presence of preying dragonfly larvae. Genetic variance in body size increased by almost an order of magnitude in the predator environment, and the first genetic principal component was found to be highly significantly different between the two environments. The across environment genetic correlation for body size was significantly below 1 indicating that different genes contributed to this trait in the two environments. Body size may therefore be able to respond to selection independently in the two environments to some extent.

Effects of anitoxidant supplementation and exercise training on erythrocyte antioxidant enzymes

Erythrocytes transport oxygen to tissues and exercise-induced oxidative stress increases erythrocyte damage and turnover. Increased use of antioxidant supplements may alter protective erythrocyte antioxidant mechanisms during training. Aim of study: To examine the effects of antioxidant supplementation, (alpha-lipoic acid and a-tocopherol) and/or endurance training on the antioxidant defenses of erythrocytes. Methods: Young male Wistar rats were. assigned to (1) sedentary; (2) sedentary and antioxidant-supplemented; (3) endurance-trained; or (4) endurance-trained and antioxidant-supplemented groups for 14 weeks. Erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) activities, and plasma malondialdehyde (MDA) were then measured. Results: Antioxidant supplementation had no significant effect (p > 0.05) on activities of antioxidant enzymes in sedentary animals. Similarly, endurance training alone also bad no effect (p > 0.05). GPX (125.9 2.8 vs. 121.5 3.0 U.gHb(-1), p < 0.05) and CAT (6.1 0.2 vs. 5.6 0.2 U.mgHb-1, p < 0.05) activities were increased in supplemented trained animals compared to non-supplemented sedentary animals whereas SOD (61.8 4.3 vs. 52.0 5.2 U.mgHb(-1), p < 0.05) activity was decreased. Plasma MDA was not different among groups (p > 0.05). Conclusions: In a rat model, the combination of exercise training and antioxidant supplementation increased antioxidant enzyme activities (GPX, CAT) compared with each individual intervention.

Dietary selectivity for the toxic cyanobacterium Lyngbya majuscula and resultant growth rates in two species of opisthobranch mollusc

Trophodynamics of blooms of the toxic marine cyanobacterium Lyngkya majuscula were investigated to determine dietary specificity in two putative grazers: the opisthobranch molluscs, Stylocheilus striatus and Bursatella leachii. S. striatus is associated with L. majuscula blooms and is known to sequester L. majuscula metabolites. The dietary specificity and toxicodynamics of B. leachii in relation to L. majuscula is less well documented. In this study we found diet history had no significant effect upon dietary selectivity of S. striatus when offered a range of plant species. However, L. majuscula chemotype may alter S. striatus' selectivity for this cyanobacterium. Daily biomass increases between small and large size groups of both species were recorded in no-choice consumption trials using L. majuscula. Both S. striatus and B. leachii preferentially consumed L. majuscula containing lyngbyatoxin-a. Increase in mass over a 10-day period in B. leachii (915%) was significantly greater than S. striatus (150%), yet S. striatus consumed greater quantities of L. majuscula (g day(-1)) and thus had a lower conversion efficiency (0.038) than B. leachii (0.081) based on sea hare weight per gram of L. majuscula consumed day(-1). Our findings suggest that growth rates and conversion efficiencies may be influenced by sea hare maximum growth potential, acquisition of secondary metabolites or diet type. (C) 2005 Elsevier B.V. All rights reserved.

O DESAFIO DA GESTÃO POR COMPETÊNCIAS NO TERCEIRO SETOR: O CASO DO PROJETO MENINOS E MENINAS DE RUA

A ação reduzida do Estado brasileiro com relação ao atendimento das necessidades das crianças e adolescentes em situação de rua dá espaço para a atuação de novos atores sociais. Alguns destes têm como objetivo promover a cidadania do país, como os participantes do terceiro setor: ONGs que enfrentam diversos obstáculos para realizar suas missões. Dentre estes desafios encontra-se a gestão de pessoas. O presente trabalho propõe a análise da gestão de pessoas e a construção participativa de um modelo de competências em uma Organização Não Governamental Projeto Meninos e Meninas de Rua, a partir da combinação das metodologias qualitativas de estudo de caso único e pesquisa-ação, tendo como embasamento a Gestão Social. A pesquisa de campo foi desenvolvida por meio de diferentes fontes de evidências: entrevistas, questionários, observação, análise de documentos e registros e artefatos físicos, que permitiu a construção participativa de um modelo com cinco (5) competências essenciais/institucionais: Diagnóstico e Planejamento, Alinhamento Institucional, Comunicação, Resiliência e Defesa, Garantia e Promoção de Direitos, tendo como foco deste trabalho o olhar para os Educadores Sociais que atuam na instituição.

CONSIDERAÇÕES ACERCA DA AUSÊNCIA PATERNA NA ADOLESCÊNCIA

O presente estudo teve por objetivos: a) Caracterizar uma amostra de adolescentes participantes de projetos sociais de uma Instituição de uma cidade do litoral paulista; b) Investigar aspectos da estrutura e dinâmica de adolescentes oriundos de famílias monoparentais, convencionais e de outras configurações familiares e, c) Compreender as relações estabelecidas com as figuras parentais por esses adolescentes pertencentes à essas diferentes organizações familiares.Para isso foi realizado inicialmente uma caracterização do perfil desses adolescentes e, posteriormente estudado seis casos de adolescentes de 12 a 18 anos participantes de Projetos Sociais do Terceiro Setor(Ong) pertencentes a diferentes formas de organizações familiares. Esses adolescentes freqüentavam a Instituição, local onde foram coletados os dados. Foram utilizados como instrumentos a entrevista semi-estruturada e o Teste de Apercepção Temática. De modo geral, os resultados mostraram que os adolescentes de famílias convencionais, ou seja, que possuem o pai e mãe no seio familiar conseguiram introjetar a imago paterna de forma mais integrada e, transitam pela adolescência de maneira mais estável. O esforço frente à elaboração dos lutos é vivenciado condizendo com a dita Síndrome da Adolescência Normal . Já os jovens pertencentes a famílias em que o pai não se faz presente no seio familiar, as defesas e as angustias apresentam-se condizentes aos estágios mais primitivos do desenvolvimento. Conclui-se que são necessários mais estudos frente a esta demanda para que o trabalho preventivo possa criar condições de um bom desenvolvimento psíquico para que este jovem passe pela adolescência e, chegue à vida adulta de maneira integrada.

CONSIDERAÇÕES ACERCA DA AUSÊNCIA PATERNA NA ADOLESCÊNCIA

O presente estudo teve por objetivos: a) Caracterizar uma amostra de adolescentes participantes de projetos sociais de uma Instituição de uma cidade do litoral paulista; b) Investigar aspectos da estrutura e dinâmica de adolescentes oriundos de famílias monoparentais, convencionais e de outras configurações familiares e, c) Compreender as relações estabelecidas com as figuras parentais por esses adolescentes pertencentes à essas diferentes organizações familiares.Para isso foi realizado inicialmente uma caracterização do perfil desses adolescentes e, posteriormente estudado seis casos de adolescentes de 12 a 18 anos participantes de Projetos Sociais do Terceiro Setor(Ong) pertencentes a diferentes formas de organizações familiares. Esses adolescentes freqüentavam a Instituição, local onde foram coletados os dados. Foram utilizados como instrumentos a entrevista semi-estruturada e o Teste de Apercepção Temática. De modo geral, os resultados mostraram que os adolescentes de famílias convencionais, ou seja, que possuem o pai e mãe no seio familiar conseguiram introjetar a imago paterna de forma mais integrada e, transitam pela adolescência de maneira mais estável. O esforço frente à elaboração dos lutos é vivenciado condizendo com a dita Síndrome da Adolescência Normal . Já os jovens pertencentes a famílias em que o pai não se faz presente no seio familiar, as defesas e as angustias apresentam-se condizentes aos estágios mais primitivos do desenvolvimento. Conclui-se que são necessários mais estudos frente a esta demanda para que o trabalho preventivo possa criar condições de um bom desenvolvimento psíquico para que este jovem passe pela adolescência e, chegue à vida adulta de maneira integrada.

RELAÇÕES OBJETAIS E ESTRUTURA DE PERSONALIDADE: MULHERES ENVOLVIDAS EM CASOS DE VIOLÊNCIA DOMÉSTICA

A violência doméstica é um fenômeno que preocupa a sociedade e deve ser objeto de destaque, é grave pois pode deixar marcas físicas e psicológicas. Ela aterroriza famílias e é assustador, principalmente por ocorrer, na maioria das vezes, no local onde as pessoas deveriam sentir-se seguras e protegidas, dentro de suas próprias casas. Há um esforço para medir a incidência da violência doméstica. Contudo, a família, a relação conjugal e o ambiente doméstico, na atualidade, ainda são considerados privados e particulares, o que dificulta a precisão da magnitude real deste tipo de violência. Assim, esta pesquisa teve como objetivo avaliar as relações objetais e estrutura de personalidade de mulheres envolvidas em casos de violência doméstica. Para tanto, utilizou-se do método qualitativo, foram avaliadas quatro mulheres envolvidas em violência doméstica, com idade superior a 18 anos. Como instrumentos foram empregados um Questionário Sociodemográfico e o Teste das Relações Objetais de Phillipson (TRO). Os resultados mostraram que a estrutura de personalidade destas mulheres apresenta-se com o predomínio de traços esquizoides. No Sistema Tensional Inconsciente Dominante, a dinâmica da personalidade apresenta medos, desejos e defesas das posições Viscocárica e Esquizoparanoide. Tal dinâmica sugere fragilidade estrutural, persecutoriedade e dependência dos objetos. Refletindo sobre a questão da violência e de como essas mulheres se submetem a ela, por meio dos resultados obtidos nesta pesquisa, observou-se que se trata de um tipo de relação de objeto com extrema dependência, permeada pelo ódio e culpa persecutória. Esta última mobiliza a permissividade do superego que precisa satisfazer todos os desejos do objeto de dependência. Ao mesmo tempo que são agredidas, elas também agridem, por não suportarem a ausência do objeto e o desejo de fundir-se a ele parece ser o gatilho que dispara os ataques. Espera-se que os resultados desta pesquisa possam levar à reflexão sobre políticas públicas e intervenções mais eficazes para diminuir a incidência deste tipo de violência e o sofrimento dessas mulheres

Characterizing Internet worm spatial-temporal infection structures

Since the Morris worm was released in 1988, Internet worms continue to be one of top security threats. For example, the Conficker worm infected 9 to 15 million machines in early 2009 and shut down the service of some critical government and medical networks. Moreover, it constructed a massive peer-to-peer (P2P) botnet. Botnets are zombie networks controlled by attackers setting out coordinated attacks. In recent years, botnets have become the number one threat to the Internet. The objective of this research is to characterize spatial-temporal infection structures of Internet worms, and apply the observations to study P2P-based botnets formed by worm infection. First, we infer temporal characteristics of the Internet worm infection structure, i.e., the host infection time and the worm infection sequence, and thus pinpoint patient zero or initially infected hosts. Specifically, we apply statistical estimation techniques on Darknet observations. We show analytically and empirically that our proposed estimators can significantly improve the inference accuracy. Second, we reveal two key spatial characteristics of the Internet worm infection structure, i.e., the number of children and the generation of the underlying tree topology formed by worm infection. Specifically, we apply probabilistic modeling methods and a sequential growth model. We show analytically and empirically that the number of children has asymptotically a geometric distribution with parameter 0.5, and the generation follows closely a Poisson distribution. Finally, we evaluate bot detection strategies and effects of user defenses in P2P-based botnets formed by worm infection. Specifically, we apply the observations of the number of children and demonstrate analytically and empirically that targeted detection that focuses on the nodes with the largest number of children is an efficient way to expose bots. However, we also point out that future botnets may self-stop scanning to weaken targeted detection, without greatly slowing down the speed of worm infection. We then extend the worm spatial infection structure and show empirically that user defenses, e.g. , patching or cleaning, can significantly mitigate the robustness and the effectiveness of P2P-based botnets. To counterattack, we evaluate a simple measure by future botnets that enhances topology robustness through worm re-infection.

Efeitos da terapia fotodinâmica com aluminio – cloro ftalocianina sobre a peroxidação lipídica e produtos antioxidantes em tecidos inflamados animais

Photodynamic therapy (PDT) consists of a non-toxic photosensitizing agent (FS) administration followed by a laser source resulting in a sequence of photochemical and photobiological processes that generate reactive oxygen species (ROS) that damaging cells. The present work evaluated the effects of PDT nanoemulsion-aluminum chloride phthalocyanine (AlClFc) mediated on malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels, which represent indicators involved in oxidative stress and antioxidant defenses. For this purpose, this study used 120 female rats of the Rattus norvegicus species, Wistar race, divided into 5 groups: Healthy (H), with periodontal disease (PD), with periodontal disease and treatment with FS (F), with periodontal disease and treatment with the laser (L); and periodontal disease and treatment with PDT (FL). An experimental model for represent periodontal disease (PD) was induced by ligature (split-mouth). Seven days later the induction of PD, the treatments were instituted according to the groups. In the group treated with PDT was applied 40μl FS (5μM) followed by laser irradiation diode InGaAlP (660nm, 100J / cm2). The rats were sacrificed on the 7th and 28th day after treatment and tissue specimens were removed and subjected to histological, immunohistochemical methods and enzymatic colorimetric measurements with detection by UV / VIS spectroscopy. Inflammatory changes, connective tissue disorganization and alveolar bone loss were displaying in groups with PD induced. The enzyme dosages showed that MDA levels were higher in PD induced groups, with no statistically significant differences (p> 0.05). High levels of GSH were found in groups L (p = 0.028) and FL (p = 0.028) compared with PD group, with statistically significant differences. Immunohistochemistry for SOD showed higher immunostaining in L and FL groups, compared to the PD group without statistically significant differences (p> 0.05). GPx showed lower immunoreactivity in the DP group when compared to the other groups and statistically significant differences were observed between the DPxL groups (p <0.05). TFD administered in this experiment did not induce elevation of MDA levels significantly increased the GSH levels and showed intense immunostaining pada SOD and GPx, showing that this therapy does not accentuated lipid peroxidation, however, it was able to induce effects on the antioxidant defenses processes. The LBI therapy appeared to show photomodulatory promoting effects reduction of the MDA levels, increasing GSH levels and with intense immunostaining for SOD and GPx, demonstrating that laser therapy induced antioxidant effects.