Effects Of Radiation Conditions Research Articles

Micropropagation of Bambusa oldhamii Munro in heterotrophic, mixotrophic and photomixotrophic systems

Photomixotrophic micropropagation systems have been associated with improved development of several plant species. In this work, we established an efficient protocol for the in vitro micropropagation of Bambusa oldhamii Munro by studying the influence of the rainy and dry seasons on plant tissue contamination, the effects of the gaseous atmosphere inside the culture flasks, and the effects of radiation conditions on plant morphogenetic events. Explants were collected from March to December 2016. The conditions consisted of 100% blue (455 nm), 100% red (630 nm), 30% blue + 70% red, and 30% red + 70% blue LED light or fluorescent light only (as a control). For induction of axillary sprouting, the explants were inoculated in MS media + 2.27 µM thidiazuron or 3.40 µM paclobutrazol. The best growth responses were observed for material collected from June to July. There was an increase of 81.79% in the number of leaves under the 30% blue + 70% red LED treatment in comparison to the control. The facilitation of gas exchange resulted in improved shoot production, with an increase of 70.80% under 30% red + 70% blue LED light in comparison to that of treatments without gas exchange. The blue LED light had an important photomorphogenic effect on the development of bamboo explants into shoots, as shoot proliferation increased. The results obtained will aid in the development of protocols for the in vitro culture of other species of bamboo as well as for the establishment of an efficient protocol to address rooting for this and other bamboo species. Minimum temperature and compensated temperature resulted in significant impact on in vitro establishment. Blue + red combined with natural ventilation resulted in efficient shoot proliferation. Paclobutrazol increased the pigment content.

One-step grafting of temperature-and pH-sensitive (N-vinylcaprolactam-co-4-vinylpyridine) onto silicone rubber for drug delivery

A one-step method was implemented to graft N-vinylcaprolactam (NVCL) and 4-vinylpyridine (4VP) onto silicone rubber (SR) films using gamma radiation in order to endow the silicone surface with temperature- and pH-responsiveness, and give it the ability to host and release diclofenac in a controlled manner and thus prevent bacterial adhesion. The effects of radiation conditions (e.g., dose and monomers concentration) on the grafting percentage were evaluated, and the modified films were characterized by means of FTIR-ATR, Raman spectroscopy, calorimetry techniques (DSC and TGA) and contact angle measurements. The films responsiveness to stimuli was evaluated by recording the swelling degree of pristine and modified SR in buffer solutions (critical pH point) and as a function of changes in temperature (Upper Critical Solution Temperature, UCST). The graft copolymers of SR-g-(NVCL-co-4VP) showed good cytocompatibility against fibroblast cells for prolonged times, could host diclofenac and release it in a sustained manner for up to 24 h, and exhibited bacteriostatic activity when challenged against Escherichia coli.

EFFECTS OF INCIDENT RADIATION AND NITROGEN AVAILABILITY ON THE QUALITY PARAMETERS OF TRITICALE GRAINS IN ARGENTINA

The effects of radiation conditions and nitrogen (N) availability on triticale were investigated. The relationship between shading (S) and N supply and their effect on the industrial use of triticale flour were studied. Incident radiation/shade conditions affected all the parameters measured. Nitrogen supply influenced yield, protein content, sodium dodecyl sulphate-sedimentation index (SDS-SI), alkaline water retention capacity (AWRC), cookie factor and diameter of four cookies (D4C). The proportion of proteins of high molecular weight was increased with nitrogen supply and pre-anthesis shade, while post-anthesis shade increased proteins of lower molecular weight. The interaction between variety and N supply was significant for yield, SDS-SI and AWRC. Only yield and specific weight were affected by N × S interaction. Significant effects of the interaction of variety, N supply and shade conditions were observed for specific weight.

Effect of radiation conditions on some properties of a polycarbonate

Samples of polycarbonate subjected to γ-radiation under different conditions have been characterized by means of intrinsic viscosity, solubility and dynamic-mechanical measurements. All the data indicate that the effect of the dose absorbed by the material increases markedly with the water content in the polymer during the irradiation. In absence of water, up to 20 Mrad, the material seems essentially insensitive to the irradiation. In the presence of water crosslinking predominates at small doses while at higher doses main chain scission is more effective.