Temperatures during flower bud development affect pollen germination, self-incompatibility reaction and early fruit development of clementine (Citrus clementina Hort. ex Tan.).

One of the key environmental factors affecting plant reproductive systems is temperature. Characterising such effects is especially relevant for some commercially important genera such as Citrus. In this genus, failure of fertilisation results in parthenocarpic fruit development and seedlessness, which is a much-prized character. Here, we characterise the effects of temperature on flower and ovary development, and on pollen-pistil interactions in 'Comune' clementine (Citrus clementina Hort. ex Tan.). We examine flower bud development, in vitro pollen germination and pollen-pistil interaction at different temperatures (15, 20, 25 or 30 °C). These temperatures span the range from 'cold' to 'hot' weather during the flowering season in many citrus-growing regions. Temperature had a strong effect on flower and ovary development, pollen germination, and pollen tube growth kinetics. In particular, parthenocarpic fruit development (indicated by juice vesicle growth) was initiated early if flowers were exposed to warmer temperatures during anthesis. Exposure to different temperatures during flower bud development also alters expression of the self-incompatibility reaction. This affects the point in the pistil at which pollen tube growth is arrested and confirms the role of sub- and supra-optimal temperatures in determining the numbers of pollen tubes reaching the ovary.

[Double phototherapy with Wallaby optic fibers versus conventional phototherapy. Case reports]. / Fototerapia doppia con fibre ottiche Wallaby versus fototerapia convenzionale. Contributo casistico.

The authors have valued the efficacy of the double phototherapy with fiberoptic Wallaby vs conventional phototherapy in 2 groups of term infants, without any complication at birth, utilized respectively as study group and control group. While conventional phototherapy produced a bilirubin reduction of 0.60 +/- 0.26% per hour (with a total reduction of 28.1 +/- 11.1%), the double phototherapy was statistically more effective (p < 0.05) then conventional phototherapy causing a bilirubin reduction of 0.73 +/- 0.28% (with a total reduction of 33.3 +/- 9.5%). At 24 hour after the interruption of the treatment 9 newborns of the study group (36%) and 7 of the control group (28%) presented a rebound effect (increase of the bilirubinemia more than 17 mumol/l), but without a statistical difference (p > 0.05). Our study shows that double phototherapy with Wallaby fiberoptic and conventional phototherapy represent a valid strategy in the treatment of the non haemolytic neonatal hyperbilirubinemia, because, compared to conventional phototherapy, double phototherapy is more effective and reduces the period of the treatment, showing a simple management of the jaundiced newborn.

Interictal EEG pattern in rabbit penicillin epilepsy.

The effects of Na-penicillin G (1,000,000 I.U./kg i.v.) were studied in 28 rabbits implanted with surface and deep electrodes in the medial (mT) and lateral (lT) nuclei of the thalamus and in the cornu Ammonis dorsalis (CAd). Attention was focused on interictal spike activity, cortical spindle activity and spikes-spindles relationship. A multifocal interictal EEG pattern, represented by cortical and thalamic spikes, was observed in 20 animals. A clear association between cortical spikes and spindles occurred almost constantly. Moreover a statistically significant increase in the average duration of spindles without changes in the average frequency was noticed. Seizure discharges had always a focal start and secondary generalization. The EEG features of parenteral penicillin epilepsy in the rabbit appeared to be more similar to those of the rat than to those of the cat. The spindle activity changes and the paroxysmal spike activity can be interpreted as two independent penicillin induced features appearing during raised cortical excitability periods.