Pollen flow between flowers of the same morph in invasive populations of <i>Oxalis pes-caprae</i> L. in the western Mediterranean region

<p><i>Oxalis pes-caprae</i> is a tristylous South African geophyte that is invasive in regions with Mediterranean climate. Given the introduction of the short-styled morph only, vegetative reproduction was, until recently, the reproductive mode known for this invaded area. The detection of new floral morphs, fruit and seed production in natural populations of the invaded range, together with the reported weakening in the heteromorphic incompatibility system, raised the question on whether the short-styled flowers are able to exchange pollen among themselves, and if so, which mechanisms account for it. Thus, flower morphometric analysis and field experiments were conducted to assess pollinator visitation rates and pollen flow in three invasive populations. Flower morphological changes suggesting the evolution from tristyly towards semi-homostyly were observed. Moreover, <i>O. pes-caprae</i> flowers were visited by different functional groups of pollinators, mostly hymenopteran. Dye flow experiments revealed that the short-styled flowers were able to successfully exchange pollen among themselves in natural conditions. All of this, together with the weakening of the incompatibility system, constitutes further data that might help to explain the recently reported occurrence of sexual reproduction in this invaded range, which by itself bears important implications for the invasion process of <i>O. pes-caprae</i>.</p

Pulsed-Laser Switching in the Bistability Domain of a Cooperative Spin Crossover Compound: A Critical Study through Calorimetry

The photoswitching from the low spin (LS) to high spin (HS) state and the reverse process in the bistability domain of spin crossover (SCO) compounds is a promising function to be used in molecular electronic devices, and evidenced mainly through spectroscopy. The phenomenon, and in particular its mechanism, is however still under debate since some controversial experimental results have been reported. Here we present a calorimetric experimental study of the photoswitching of the [Fe­(pyrazine)­Pt­(CN)₄] SCO material by a nanosecond-pulsed green laser. Our results confirm that the single laser pulse of varying energies results in significant LS to HS transformations and show that calorimetry provides an accurate quantification of the overall conversion. Successive pulses allow increasing the conversion, achieving a maximum of 60% under our experimental conditions. The HS to LS transformation is on the other hand not induced at any laser fluences contrary to previous reports. The results are compared with those reported with Raman spectroscopy and critically discussed in terms of efficiency of the transformation and potential thermal effects

Management of severe malarial infection.

Severe malaria is a major cause of infant and childhood death in the tropics. Effective management relies on rapid diagnosis, prompt administration of parenteral schizonticidal antimalarial drugs, careful fluid balance, prevention of convulsions and early recognition of complications such as hypoglycemia, metabolic acidosis, anemia, pulmonary edema, renal failure, bleeding and supervening bacterial sepsis. The mortality of treated cerebral malaria remains 20%. New, more rapidly acting antimalarials and earlier referral of children with complicated infections should reduce this unacceptable death rate