Is it possible to measure good science?

Metrics play a vital part in the valuation and funding of research for scientists worldwide. We review the challenges that metrics pose in providing a fair and equitable system for research funding. We highlight the attempts with declarations, including the San Francisco Declaration on Research Assessment (SF-DORA), to improve the research environment and specific impacts that metric choice can have on the evaluation and progression of Early Career Lecturers (ECLs). While there is much evidence that metrics will never be entirely satisfactory, we conclude there are opportunities that would benefit ECLs and reason for optimism for researchers.

Encapsulation of in vitro Plectranthus amboinicus (Lour.) Spreng. shoot apices for propagation and conservation.

This investigation demonstrates an efficient method of propagation, short-term conservation, and germplasm exchange for Plectranthus amboinicus (Lour.) Spreng. encapsulated propagules. In vitro-derived shoot apices (shoot tips and nodal segments) which showed 100% survival on MS medium supplemented with 0.4 mg/L 6-benzylaminopurine were selected for encapsulation studies. Shoot apices measuring about 3-5 mm in size showed the ability to break the beads and exhibited 100% survival and regrowth. The combination of 3% (w/v) sodium alginate and 100 mM CaCl2 was found to be ideal for forming uniformally spherical beads, and successive preservation of encapsulated shoot apices into plantlets. The encapsulated shoot tips were relatively more effective than the nodal segments in terms of shoot growth and multiplication. Encapsulated shoot tips retained the ability to regrow (63.3%) for up to 40 days when maintained at 4 °C. Encapsulated shoot tips effectively converted into plantlets on agar medium (78%) and peat moss (58%) under in vitro conditions. Encapsulated shoot tips on agar medium showed a higher shoot regeneration (9.91 ± 0.15 shoots per explant) ability than the peat moss (5.71 ± 0.34 shoots per explant), while the highest rooting (12.16 ± 0.23 roots per explant) was observed on peat moss. Thus, calcium alginate encapsulation holds latent qualities that could be explored to develop a future alternative method of propagation, short-term storage and germplasm distribution for elite genotypes of Plectranthus sp.

HPLC analysis of plant DNA methylation: a study of critical methodological factors.

HPLC analysis of nucleosides is important for determining total DNA methylation in plants and can be used to help characterise epigenetic changes during stress, growth and development. This is of particular interest for in vitro plant cultures as they are highly susceptible to genetic change. HPLC methodologies have been optimised for mammalian and microbial DNA, but not for plants. This study examines critical methodological factors in the HPLC analysis of plant DNA methylation using in vitro cultures of Ribes ciliatum. HPLC revealed that complete removal of RNA from plant DNA extractions is difficult using RNase (A and T1) digestions and LiCl precipitation. This suggests that base analysis should be avoided when using these RNA removal techniques, as bases from residual RNA fragments will inflate peak areas for DNA-derived bases. Nucleoside or nucleotide analysis is therefore recommended as a more suitable option as RNA and DNA constituents can be readily separated. DNA digestion was also a critical factor as methylation was under-estimated following incomplete nuclease digestion and over-estimated following incomplete phosphatase digestion. The units of enzyme required for complete DNA digestion was optimised and found to be 20-200 times less for nuclease P1 and 15 times less for alkaline phosphatase as compared with previous protocols. Digestion performance was conveniently monitored using marker peaks that indicate incomplete digestion products. This study identifies critical components of HPLC analysis and offers a comprehensive guide for the stringent analysis of DNA methylation in plants.

Effects of osmotic pretreatments on oxidative stress, antioxidant profiles and cryopreservation of olive somatic embryos.

A three-day pretreatment of olive somatic embryos (SE) with 0.75 M sucrose, combined with cryoprotection (0.5M DMSO, 1M sucrose, 0.5M glycerol and 0.009 M proline) and controlled rate cooling, supported regrowth (as 34.6% fresh weight gain) and resumption of embryo development after cryopreservation. Pretreatment with mannitol or sorbitol did not support regrowth. Profiles of sugars, proline, antioxidant enzymes, Reactive oxygen species (ROS), secondary oxidation products and ethylene were constructed for the most successful (0.75 M) pretreatment series. Sucrose was the optimal pretreatment for supporting recovery, it also elevated glutathione reductase (GR) activity compared to controls, whereas superoxide dismutase (SOD), catalase and guaiacol peroxidase activities remained relatively unchanged. Superoxide dismutase activity was higher in SE pretreated with sucrose, compared with those pretreated with polyols; H(2)O(2) was enhanced in SE pretreated with sorbitol and sucrose compared to mannitol. The overall trend for ethylene and OH production revealed their levels were highest in SE pretreated with polyols albeit, for individual treatments this was not always the case. Generally, pretreatments did not significantly change embryo secondary oxidation profiles of ThioBarbituric Acid Reactive Substances (TBARS) and Schiff's bases. In combination these studies suggest oxidative processes may influence regrowth of cryopreserved olive SE and that optimal pretreatments could, in part, increase tolerance by an overall enhancement of endogenous antioxidants (particularly GR), proline and sugars.