As part of an environmental risk assessment study of exotic natural enemies used in inundative biological control, life-history characteristics of Harmonia axyridis (Pallas), Hippodamia variegata (Goeze) and Adalia bipunctata (L.) (Col., Coccinellidae) were quantified under laboratory conditions at 25°C on Myzus persicae (Sulzer) as prey. Comparative studies showed significant differences among pre-adult development times: H. axyridis developed slower ( X ¼ 19.8 days) than H. variegata ( X ¼ 18.1 days) and A. bipunctata ( X ¼ 18.4 days). Differences were also evident in the duration of egg, larval and pupal stages. No measurable differences among the three species were found for fecundity, oviposition rate and adult longevity. Harmonia axyridis exhibited the longest pre-oviposition ( X ¼ 7.4 days) and interoviposition ( X ¼ 3.6 days) periods and the shortest oviposition period ( X ¼ 13.7 days). The Bieri model was used to describe age-specific fecundity for the three species of coccinellids. The intrinsic rate of increase (r m ), net reproductive rate (R 0 ) and mean generation time (T) were higher for H. variegata (r m ¼ 0.114, R 0 ¼ 52.75, T ¼ 41.88 days) than for H. axyridis (r m ¼ 0.089, R 0 ¼ 26.27, T ¼ 38.81 days) or A. bipunctata (r m ¼ 0.081, R 0 ¼ 18.49, T ¼ 40.06 days). Our findings show that the biological traits of H. axyridis do not seem to be factors that may contribute to the invasiveness of this coccinellid.

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Background: The role of nasal continuous positive airways pressure (nCPAP) in the management of respiratory distress syndrome in preterm infants is not completely defined. Objective: To evaluate the benefits and risks of prophylactic nCPAP in infants of 28-31 weeks gestation. Design: Multicentre randomised controlled clinical trial. Setting: Seventeen Italian neonatal intensive care units. Patients: A total of 230 newborns of 28-31 weeks gestation, not intubated in the delivery room and without major malformations, were randomly assigned to prophylactic or rescue nCPAP. Interventions: Prophylactic nCPAP was started within 30 minutes of birth, irrespective of oxygen requirement and clinical status. Rescue nCPAP was started when FIO 2 requirement was . 0.4, for more than 30 minutes, to maintain transcutaneous oxygen saturation between 93% and 96%. Exogenous surfactant was given when FIO 2 requirement was . 0.4 in nCPAP in the presence of radiological signs of respiratory distress syndrome. Main outcome measures: Primary end point: need for exogenous surfactant. Secondary end points: need for mechanical ventilation and incidence of air leaks. Results: Surfactant was needed by 22.6% in the prophylaxis group and 21.7% in the rescue group. Mechanical ventilation was required by 12.2% in both the prophylaxis and rescue group. The incidence of air leaks was 2.6% in both groups. More than 80% of both groups had received prenatal steroids. Conclusions: In newborns of 28-31 weeks gestation, there is no greater benefit in giving prophylactic nCPAP than in starting nCPAP when the oxygen requirement increases to a FIO 2 . 0.4.

As consequence of the concern about the biosafety of genetically modified plants, biological and ecological studies are considered crucial for environmental risk assessment. Laboratory experiments were carried out in order to evaluate the transfer of the Cry1Ac Bt-toxin from a transgenic Bt-oilseed rape to a non-target pest, Myzus persicae Sulzer. Cry1Ac protein levels in plants and aphids were determined using a double sandwich enzyme-linked immunosorbent assay. Phloem sap from (Bt+) and (Bt-) oilseed rape plants was collected from leaves using a standard method of extraction in an EDTA buffer. Bt-toxin was present in phloem sap, with a mean concentration of 2.7 +/- 1.46 ppb, corresponding to a 24-fold lower level than in oilseed rape leaves. Toxin was also detected in aphid samples, with a mean concentration in the positive samples of 2.0 +/- 0.8 ppb. The evidence that Bt-toxin remains in herbivores, in this case an aphid, could be useful to clarify functional aspects linked to possible consequences of Bt-crops on food chains involving herbivore-natural enemy trophic systems. Further studies are needed in order to improve the knowledge on the functional aspects linked to the transfer of the Cry1Ac Bt-toxin from GM-oilseed rape to aphids and their possible consequence.

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