Non-canonical auxin signalling : fast and curious

Many plant biologists might think that the auxin signalling pathway has been resolved. Activation of gene expression as a result of indole-3-acetic acid (IAA)-mediated assembly of Transport Inhibitor1 (TIR1)/Auxin F-Box (AFB) proteins with AUX/IAA transcriptional regulators has become accepted as the canonical auxin signalling pathway. However, the evidence strongly suggests that non-canonical pathways will still prove to be important, and this theme ran through the 2018 Auxins and Cytokinins in Plant Development conference held in Prague (ACPD 2018)

Stress management and organisation development : effects of transcendental meditation on psychological, physiological, and organisational variables at the worksite

Bibliography: p. 348-363.This study evaluated the effectiveness of a stress reduction intervention (SRI) offered to employees at one worksite where 80 were employed. 41 Volunteers (aged 21-65) participated in Transcendental Meditation (TM), and 18 (aged 19-46) in Progressive Muscle Relaxation (PMR). Two groups did not attend the SRI. These were 11 non-volunteers for the SRI (aged 25-58) who served as on-site controls, while 16 outside attendees (aged 27-44) of a personal productivity workshop served as offsite controls. All subjects completed a standardised stress symptoms questionnaire (SCL-90-R) before and after the SRI. On-site subjects also had blood pressure, heart and breath rates measured by a trained nurse and completed a company climate questionnaire-before and after the SRI. Structured interviews were conducted at three year followup. An hypothesis that test groups would show significant reductions in psychological stress symptoms was supported at 6-week (TM p<0,0001, PMR p<0,001) and 5,5 month followup (p<0,0002, paired-t). TM groups showed significant reductions in blood pressure at 5,5 month followup (p<0,05). Overall company climate showed improvement at 6 weeks which tended to reverse at 5,5 months, following retrenchment of 10 staff. Psychological and physiological variables were found to be positively correlated. Non-volunteer on-site controls appeared to benefit almost as much as those who received training, whereas off-site controls did not. Company effectiveness improved over three years following the intervention though causality was not addressed

Factors Associated with Blockages to Outdoor Recreation Participation: A State Survey

Data from a random sample of Ohio residents were used in an attempt to isolate factors that were hypothesized to be related to outdoor recreation blockages. The study revealed that socio-demographic variables failed to explain the variance in factor scores created to measure blockages to outdoor recreation. Findings from descriptive statistics and the factor analyses are discussed in a planning context

Nucleic acid aptamers as aptasensors for plant biology

Our knowledge of cell- and tissue-specific quantification of phytohormones is heavily reliant on laborious mass spectrometry techniques. Genetically encoded biosensors have allowed spatial and some temporal quantification of phytohormones intracellularly, but there is still limited information on their intercellular distributions. Here, we review nucleic acid aptamers as an emerging biosensing platform for the detection and quantification of analytes with high affinity and specificity. Options for DNA aptamer technology are explained through selection, sequencing analysis and techniques for evaluating affinity and specificity, and we focus on previously developed DNA aptamers against various plant analytes. We suggest how these tools might be applied in planta for quantification of molecules of interest both intracellularly and intercellularly

Fractional boundary value problems: Analysis and numerical methods

This is the author's PDF of an article published in Fractional calculus and applied analysis 2011. The original publication is available at www.springerlink.comThis journal article discusses nonlinear boundary value problems.Fundacao para a Ciencia e Tecnologi

Tomographic docking suggests the mechanism of auxin receptor TIR1 selectivity

We study the binding of plant hormone IAA on its receptor TIR1 introducing a novel computational method that we call tomographic docking and that accounts for interactions occurring along the depth of the binding pocket. Our results suggest that selectivity is related to constraints that potential ligands encounter on their way from the surface of the protein to their final position at the pocket bottom. Tomographic docking helps develop specific hypotheses about ligand binding, distinguishing binders from non-binders, and suggests that binding is a three-step mechanism, consisting of engagement with a niche in the back wall of the pocket, interaction with a molecular filter which allows or precludes further descent of ligands, and binding on the pocket base. Only molecules that are able to descend the pocket and bind at its base allow the co-receptor IAA7 to bind on the complex, thus behaving as active auxins. Analyzing the interactions at different depths, our new method helps in identifying critical residues that constitute preferred future study targets and in the quest for safe and effective herbicides. Also, it has the potential to extend the utility of docking from ligand searches to the study of processes contributing to selectivity.Comment: 11 pages, 7 figure