351 research outputs found
Chemical genetics uncovers novel inhibitors of lignification, including p-iodobenzoic acid targeting CINNAMATE-4-HYDROXYLASE
Plant secondary-thickened cell walls are characterized by the presence of lignin, a recalcitrant and hydrophobic polymer that provides mechanical strength and ensures long-distance water transport. Exactly the recalcitrance and hydrophobicity of lignin put a burden on the industrial processing efficiency of lignocellulosic biomass. Both forward and reverse genetic strategies have been used intensively to unravel the molecular mechanism of lignin deposition. As an alternative strategy, we introduce here a forward chemical genetic approach to find candidate inhibitors of lignification. A high-throughput assay to assess lignification in Arabidopsis (Arabidopsis thaliana) seedlings was developed and used to screen a 10-k library of structurally diverse, synthetic molecules. Of the 73 compounds that reduced lignin deposition, 39 that had a major impact were retained and classified into five clusters based on the shift they induced in the phenolic profile of Arabidopsis seedlings. One representative compound of each cluster was selected for further lignin-specific assays, leading to the identification of an aromatic compound that is processed in the plant into two fragments, both having inhibitory activity against lignification. One fragment, p-iodobenzoic acid, was further characterized as a new inhibitor of CINNAMATE 4-HYDROXYLASE, a key enzyme of the phenylpropanoid pathway synthesizing the building blocks of the lignin polymer. As such, we provide proof of concept of this chemical biology approach to screen for inhibitors of lignification and present a broad array of putative inhibitors of lignin deposition for further characterization
Using Kites for Meteorological Measurement of the Tropical Marine Boundary Layer.
M.S. Thesis. University of Hawaiʻi at Mānoa 2018
User responses to information systems change: The place of negative capability
This study explores the place of the notion of negative capability in user responses to information systems change. Much has been written about information systems change, significantly less about negative capability, and there has been no research, at all, that links the two.User responses to the implementation of new IT have been researched since the advent of computers in organizations. Most of the existing research, however, examines situations where use is optional. This study argues that IT use is now often mandatory in most forms of organization – whether public, private or charitable. This has significant implications not only for people working in organizations that implement new IT but also for the research of such events.Negative capability has, over the past several years, started to appear in the management literature as a capacity that is uncovered when people hold an open mind during experiences of uncertainty and anxiety and resist the urge to grasp impatiently for any solution. This is sometimes contrasted with positive capabilities, which are based on a particular skill or knowledge base. Without the practice of negative capability, we observe people engaging in ‘dispersal’. This is the tendency under conditions of uncertainty to lose focus on the task and to disperse into intellectual, emotional and/or behavioural responses that do not serve the intended purpose. This paper adds to the body of knowledge by expanding our understanding of the notion of negative capability in responses to mandatory use of new IT with field studies.The research consists of two cases. The first case involves the experiences of paramedics when they convert from paper- to electronic-based reporting. The second case explores the implementation of an ERP system in a manufacturing organization. This research contributes to the body of knowledge in three ways. It is the first time that negative capability has been considered in the context of information systems/information technology change. It is novel in that it considers the emergence of negative capability after the demonstration of dispersal behaviours and it identifies instances in which such dispersal behaviours may be beneficial. A significant outcome is the development of a new analytical framework for researching and understanding negative capability during organizational change, exploring the capacity to practice negative capability at three organizational levels: organizational, relational and personal
UREKA: Umbilical Ring Easy Kannula Access
The umbilical ring easy kannula access appears to provide a safe portal of laparoscopic entry in pediatric patients with few complications
Outcomes of truncal vascular injuries in children.
BACKGROUND: Pediatric truncal vascular injuries occur infrequently and have a reported mortality rate of 30% to 50%. This report examines the demographics, mechanisms of injury, associated trauma, and outcome of patients presenting for the past 10 years at a single institution with truncal vascular injuries.
METHODS: A retrospective review (1997-2006) of a pediatric trauma registry at a single institution was undertaken.
RESULTS: Seventy-five truncal vascular injuries occurred in 57 patients (age, 12 +/- 3 years); the injury mechanisms were penetrating in 37%. Concomitant injuries occurred with 76%, 62%, and 43% of abdominal, thoracic, and neck vascular injuries, respectively. Nonvascular complications occurred more frequently in patients with abdominal vascular injuries who were hemodynamically unstable on presentation. All patients with thoracic vascular injuries presenting with hemodynamic instability died. In patients with neck vascular injuries, 1 of 2 patients who were hemodynamically unstable died, compared to 1 of 12 patients who died in those who presented hemodynamically stable. Overall survival was 75%.
CONCLUSIONS: Survival and complications of pediatric truncal vascular injury are related to hemodynamic status at the time of presentation. Associated injuries are higher with trauma involving the abdomen
Nemesia Root Hair Response to Paper Pulp Substrate for Micropropagation
Agar substrates for in vitro culture are well adapted to plant micropropagation, but not to plant rooting and acclimatization. Conversely, paper-pulp-based substrates appear as potentially well adapted for in vitro culture and functional root production. To reinforce this hypothesis, this study compares in vitro development of nemesia on several substrates. Strong differences between nemesia roots growing in agar or in paper-pulp substrates were evidenced through scanning electron microscopy. Roots developed in agar have shorter hairs, larger rhizodermal cells, and less organized root caps than those growing on paper pulp. In conclusion, it should be noted that in this study, in vitro microporous substrates such as paper pulp lead to the production of similar root hairs to those found in greenhouse peat substrates. Consequently, if agar could be used for micropropagation, rooting, and plant acclimatization, enhancement could be achieved if rooting stage was performed on micro-porous substrates such as paper pulp
What do young adolescents think about taking part in longitudinal self-harm research?: findings from a school-based study
Background: Research about self-harm in adolescence is important given the high incidence in youth, and strong links to suicide and other poor outcomes. Clarifying the impact of involvement in school based self-harm studies on young adolescents is an ethical priority given heightened risk at this developmental stage. Methods: Here, 594 school-based students aged mainly 13-14 years completed a survey on self-harm at baseline and again 12-weeks later. Change in mood following completion of each survey, ratings and thoughts about participation, and responses to a mood-mitigation activity were analysed using a multi-method approach. Results: Baseline participation had no overall impact on mood. However, boys and girls reacted differently to the survey depending on self-harm status. Having a history of self-harm had a negative impact on mood for girls, but a positive impact on mood for boys. In addition, participants rated the survey in mainly positive/neutral terms, and cited benefits including personal insight and altruism. At follow-up, there was a negative impact on mood following participation, but no significant effect of gender or self-harm status. Ratings at follow-up were mainly positive/neutral. Those who had self-harmed reported more positive and fewer negative ratings than at baseline: the opposite pattern of response was found for those who had not self-harmed. Mood mitigation activities were endorsed. Conclusions: Self-harm research with youth is feasible in school settings. Most young people are happy to take part and cite important benefits. However, the impact of participation in research appears to vary according to gender, self-harm risk and method/time of assessment. The impact of repeated assessment requires clarification. Simple mood-elevation techniques may usefully help to mitigate distress
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