How predation by Podisus nigrispinus is influenced by developmental stage and density of its prey Alabama argillacea

The functional response of a predator to the density of its prey is affected by several factors, including the prey's developmental stage. This study evaluated the functional response of Podisus nigrispinus (Dallas) (Hemiptera: Heteroptera: Pentatomidae) females to fourth instars and pupae of Alabama argillacea (Hübner) (Lepidoptera: Noctuidae), an important pest of cotton (Gossypium hirsutum L., Malvaceae) in Brazil. The prey were exposed to the predator for 12 and 24 h, and in densities of 1, 6, 12, 18, 24, and 30 items per predator female. The predation data were subjected to polynomial regression logistic analysis to determine the type of functional response. Holling and Rogers' equations were used to estimate parameters such as attack rate and handling time. Podisus nigrispinus females showed functional response types II and III by preying on larvae and pupae, respectively. The attack rate and handling time did not differ between the 12 and 24 h exposure times. Predation rate was higher at higher larval and pupal densities; predation was highest at a density of 30 prey items per female, and it was similar at 18 and 24 prey per predator. Understanding the interaction of predators and their food resources helps to optimize biological control strategies. It also helps the decision‐making and the improvement of release techniques of P. nigrispinus in the field.     

Visitation rate of pollinators and nectar robbers to the flowers and inflorescences of Tabebuia aurea (Bignoniaceae): effects of floral display size and habitat fragmentation

Large floral displays favour pollinator attraction and the import and export of pollen. However, large floral displays also have negative effects, such as increased geitonogamy, pollen discounting and nectar/pollen robber attraction. The size of the floral display can be measured at different scales (e.g. the flower, inflorescence or entire plant) and variations in one of these scales may affect the behaviour of flower visitors in different ways. Moreover, the fragmentation of natural forests may affect flower visitation rates and flower visitor behaviour. In the present study, video recordings of the inflorescences of a tree species (Tabebuia aurea) from the tropical savannah of central Brazil were used to examine the effect of floral display size at the inflorescence and tree scales on the visitation rate of pollinators and nectar robbers to the inflorescence, the number of flowers approached per visit, the number of visits per flower of potential pollinators and nectar robbers, and the interaction of these variables with the degree of landscape disturbance. Nectar production was quantified with respect to flower age. Although large bees are responsible for most of the pollination, a great diversity of flower insects visit the inflorescences of T. aurea. Other bee and hummingbird species are highly active nectar robbers. Increases in inflorescence size increase the visitation rate of pollinators to inflorescences, whereas increases in the number of inflorescences on the tree decrease visitation rates to inflorescences and flowers. This effect has been strongly correlated with urban environments in which trees with the largest floral displays are observed. Pollinating bees (and nectar robbers) visit few flowers per inflorescence and concentrate visits to a fraction of available flowers, generating an overdispersed distribution of the number of visits per inflorescence and per flower. This behaviour reflects preferential visits to young flowers (including flower buds) with a greater nectar supply.     

Computational identification and comparative analysis of miRNA precursors in three palm species

Planta - In the present study, miRNA precursors in the genomes of three palm species were identified. Analyzes of sequence conservation and biological function of their putative targets contribute...     

Experimental test of the ecosystem impacts of the keystone predator Triops cancriformis (Branchiopoda: Notostraca) in temporary ponds

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Microboring organisms in living stylasterid corals (Cnidaria,Hydrozoa)

Microboring or euendolithic microorganisms, which colonize and penetrate various carbonate substrates, are abundant in coral reef ecosystems and play a major role in reef carbonate dissolution. A few studies reported the presence of euendoliths in stylasterid coral skeletons but the biological identity, distribution and abundance of these microorganisms remain largely unknown. Observations of over 100 stylasterid colonies, collected in the Indo-Pacific area, revealed for the first time that the association between these corals and euendolith organisms appears to be quite common in shallow tropical waters. The most abundant euendolith was identified as a cryptic stage in the development of the rhodophyte Porphyra (Conchocelis stage). The euendoliths were observed in the skeletons of seven species of three genera (four Stylaster, two Distichopora and one Lepidotheca). The presence of euendoliths inside skeletons conferred a particular colour to the studied stylasterid corals. Distribution and abundance of microborings varied significantly among stylasterid species and among branches of a single colony and so did the colour of their skeletons. Colonization of skeletons and the associated colour distribution were almost uniform in some stylasterids, forming an upward gradually diminishing or sharply limited gradient. This study shows that patterns of euendolith colonization and growth in stylasterid skeletons may depend on the stage of the euendolith development as well as on their environmental requirements such as light exposure.     

Effect of polymorphisms in the CD36 and STAT3 genes on different dietary interventions among patients with coronary artery disease: study protocol for a randomized controlled trial

BackgroundCardiovascular disease has become a major health problem, and it has been associated with both environmental and genetic factors. Studies have shown that the Mediterranean Diet (MeDiet), or its components such as nuts and olive oil, may be strongly associated with the improvement of cardiovascular risk factors in specific populations. The purpose of the GENUTRI study is to investigate the interaction of genetics with cardiovascular risk factors in a non-Mediterranean population with coronary artery disease (CAD) according to three different diets: rich in pecan nuts, in extra-virgin olive oil or a control diet.Methods/designThe GENUTRI study is a single-center, randomized, open-label, parallel-group, 12-week pragmatic clinical trial conducted in patients aged 40 to 80 years and diagnosed with CAD. A standardized questionnaire will be applied to data collection and a blood sample will be obtained for lipid, glycemic and inflammatory profile evaluation. Polymorphisms in the CD36 and STAT3 genes will be detected using the TaqMan® SNP Genotyping Assay. Patients will be allocated in three groups: group 1: 30 g/day of pecan nuts; group 2: 30 ml/day of olive oil; and group 3: control diet. The primary outcome will consist of changes in LDL-cholesterol (in mg/dl) after 12 weeks of intervention.DiscussionStudies have shown the beneficial effects of diets rich in nuts and olive oil mainly in the Mediterranean population. GENUTRI is a clinical trial focusing on the effects of nuts or olive oil supplementation in Brazilian individuals. Additionally, we will try to demonstrate that genetic polymorphisms linked to cardiovascular disease may modulate the effects of different diets on biochemical and inflammatory markers among these subjects.

Trial registration

ClinicalTrials.gov Identifier: {"type":"clinical-trial","attrs":{"text":"NCT02202265","term_id":"NCT02202265"}}NCT02202265 (registered on 18 July 2014: first version).     

Culture medium influence on growth,fatty acid,and pigment composition of <Emphasis Type="Italic">Choricystis minor</Emphasis> var. <Emphasis Type="Italic">minor</Emphasis>: a suitable microalga for biodiesel production

The purposes of this study were to assess the influence of culture medium on biomass production, fatty acid, and pigment composition of Choricystis minor var. minor and to evaluate the use of this microalga as a source of fatty raw material for biodiesel production. Cultures of C. minor var. minor were grown using WC (Wright’s cryptophyte) and BBM (Bold’s Basal medium) media. BBM medium produced more biomass (984.3 mg L^?1) compared to the WC medium (525.7 mg L^?1). Despite this result, WC medium produced a higher methyl ester yield for biodiesel production than the BBM medium (170.0 and 90.2 mg g^?1 of biomass, respectively). The average percentage of fatty acids obtained using the WC medium (17.0 %) was similar to soybean (18.0 %) and with similar biomass fatty acid profile. However, for pigment production, carotenoids and chlorophyll concentrations were twice as high when using the BBM medium.     

Oxygen consumption and ammonia excretion of juvenile pink shrimp (Farfantepenaeus paulensis) in culture: temperature effects

We evaluated oxygen consumption and ammonia excretion by juveniles of the pink shrimp Farfantepenaeus paulensis at three different temperatures (15, 20 and 25 °C). The shrimp were collected in the coastal region of Cananéia, São Paulo State, Brazil. The selected temperatures are the limits recorded in aquaculture tanks in the coastal region of Cananéia. We measured oxygen consumption and ammonia excretion as proxies for metabolic activity. Oxygen consumption and ammonia excretion increased with increasing temperature, but no change was observed at 15 and 20 °C. It is possible that within this temperature range, there is thermal independence in juvenile F. paulensis do not need to allocate additional energy to compensate for temperature changes because they are physiologically adapted for this range.     

Effects of IGF‐1 isoforms on muscle growth and sarcopenia

The decline in skeletal muscle mass and strength occurring in aging, referred as sarcopenia, is the result of many factors including an imbalance between protein synthesis and degradation, changes in metabolic/hormonal status, and in circulating levels of inflammatory mediators. Thus, factors that increase muscle mass and promote anabolic pathways might be of therapeutic benefit to counteract sarcopenia. Among these, the insulin‐like growth factor‐1 (IGF‐1) has been implicated in many anabolic pathways in skeletal muscle. IGF‐1 exists in different isoforms that might exert different role in skeletal muscle. Here we study the effects of two full propeptides IGF‐1Ea and IGF‐1Eb in skeletal muscle, with the aim to define whether and through which mechanisms their overexpression impacts muscle aging. We report that only IGF‐1Ea expression promotes a pronounced hypertrophic phenotype in young mice, which is maintained in aged mice. Nevertheless, examination of aged transgenic mice revealed that the local expression of either IGF‐1Ea or IGF‐1Eb transgenes was protective against age‐related loss of muscle mass and force. At molecular level, both isoforms activate the autophagy/lysosome system, normally altered during aging, and increase PGC1‐α expression, modulating mitochondrial function, ROS detoxification, and the basal inflammatory state occurring at old age. Moreover, morphological integrity of neuromuscular junctions was maintained and preserved in both MLC/IGF‐1Ea and MLC/IGF‐1Eb mice during aging. These data suggest that IGF‐1 is a promising therapeutic agent in staving off advancing muscle weakness.