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Born with bristles: New insights on the Kölliker’s organs of Octopus skin
No full textThe entire skin surface of octopus embryos, hatchlings and juveniles bears scattered
tufts of tiny chitinous setae within small pockets, from which they can be everted and
retracted. Known as Kölliker’s organs (KO), they disappear before the subadult stage.
The function of these structures during the early life of the octopus is unknown, despite
having been first described nearly two centuries ago. To investigate these organs further,
general trends in size of KO distribution and density were analyzed in hatchlings and
juveniles of 17 octopod species from all oceans, representing holobenthic, holopelagic
and meropelagic modes of life. The size of the KO is fairly constant across species,
unrelated to mode of life or hatchling size. The density of KO is similar on ventral and
dorsal body surfaces, but hatchlings of smaller size tend to have a higher density of KO
on the aboral surface of the arms. Analysis of a series of post-hatching Octopus vulgaris
shows KO size to be constant throughout ontogeny; it is therefore a consistent structure
during the octopus early life from planktonic hatchling to benthic juvenile. New KO are
generated on the skin of the arm tips during the planktonic period and initial benthic
lives of juveniles. Their density, on both the mantle and arms, gradually decreases as
the octopus grows. In older benthic juveniles, the KO degrades, losing its setae and the
base of its follicle becomes exposed as a nearly circular stump of muscle. It is estimated
that fully everted KO increase the body surface area by around two-thirds compared
to when the KO are retracted. This modular mechanism of body surface extension and
roughness probably influences flow-related forces such as drag and propulsion of the
moving surface of the young octopus while it is of small size with a relatively large surface
area. In addition, the distribution of these organs on the aboral surface of the arms of the
octopus and their birefringent properties suggest a role in camouflage. Further research
is needed to test these hypotheses of KO function in live animals.FF-Á was supported by an Irish Research Council-Government of
Ireland Postdoctoral Fellowship Award (Ref. GOIPD/2019/460).
Material contributed by IGG was collected partly through the
support of funding from the Japan Science and Technology
Agency (grant nos. J130000263, J170000574, AS2715164U and
AS0138002); and partly through travel support from the Okinawa
Institute of Science and Technology (OIST). SC acknowledges the funding of a FONDECYT research grant (#11170617).
Part of material contributed by NO was obtained under the
project PICT 201 0670 from the National Agency for Scientific
and Technological Research of Argentina. Project funding and
support to RV was provided by the Spanish Ministry of Science,
Innovation and Universities (OCTOSET project, RTI2018-
097908-B-I00, MCIU/AEI/FEDER, EU), the Spanish Ministry of
Education (grant PRX19/00153) and the Spanish government
through the “Severo Ochoa Center of Excellence” accreditation
(CEX2019-000928-S)
A call for the standardised reporting of factors affecting the exogenous loading of extracellular vesicles with therapeutic cargos
No full textExtracellular vesicles (EVs) are complex nanoparticles required for the intercellular transfer of diverse biological cargoes. Unlike synthetic nanoparticles, EVs may provide a natural platform for the enhanced targeting and functional transfer of therapeutics across complex and often impenetrable biological boundaries (e.g. the blood–brain barrier or the matrix of densely organised tumours). Consequently, there is considerable interest in utilising EVs as advanced drug delivery systems for the treatment of a range of challenging pathologies. Within the past decade, efforts have focused on providing standard minimal requirements for conducting basic EV research. However, no standard reporting framework has been established governing the therapeutic loading of EVs for drug delivery applications. The purpose of this review is to critically evaluate progress in the field, providing an initial set of guidelines that can be applied as a benchmark to enhance reproducibility and increase the likelihood of translational outcomes
Mental health problems, family functioning and social support among children survivors of Colombia’s armed conflict
No full textPurpose - Colombia has one of the largest armed conflict in the world. Children exposed directly or indirectly to armed conflicts lives the emotional footprints left by war. This study identified mental health problems among children survivors of Colombia’s armed conflict and associated factors. Design/methodology/approach – A cross-sectional study with (n=80) children aged 7 to 11 years (M=9.8 years; SD= 1.4) was conducted using the Child Behavior Checklist, Family APGAR and MOS social support survey adaptation to children. Linear regression analyses were also performed with emotional and behavioral problems as the outcomes and related factors as the predictors. Findings - Clinical levels of emotional and behavioral problems were found in 56.3% of children. Internalizing problems (63.7%) were more common than externalizing problems (51.2%). Older children had greater emotion problems, at the trend level, and those with higher functioning families had lower emotion problems. Children with higher perceived social support had lower behavior problems, at the trend level. Research limitations/implications - This study includes a sample facing multiple risks and uses a holistic approach to consider family and social resources that may support children who are survivors of the armed conflict in Colombia. These results provide a foundation for future promotion and prevention programs related to children’s mental health problems in order to support peacebuilding within the framework of the Colombian post conflict process. Originality/value – To the best of authors’ knowledge, this is the first study to collect empirical data on the mental health of children survivors of Colombia’s armed conflict focused in the Atlantic Department.Ministerio de Ciencia, Tecnología e Innovación – Minciencias, Gobernación del AtlánticoFormación de Capital Humano de Alto Nivel para las Regiones – Atlántico 2018COLFUTUROUniversidad Simón Bolívar in Barranquilla, Colombi
Energy harvesting wireless sensor network edge device simulation tool
No full textWireless Sensor Networks (WSN) are Internet of Things (IoT) edge devices. They are becoming widely adopted in many industries including health care, building energy management and conditional monitoring. As the scale of WSN deployments increases, the cost and complexity of battery replacement and disposal become more significant and in time may become a barrier to adoption. Harvesting ambient energies provides a pathway to reducing dependence on batteries and in the future may lead to autonomously powered sensors. This work describes a simulation tool that enables the user to predict the battery life of a wireless sensor that utilizes energy harvesting to supplement the battery power. To create this simulator, all aspects of a typical WSN edge device were modelled including, sensors, transceiver and microcontroller as well as the energy source components (batteries, photovoltaic cells, thermoelectric generators (TEG), supercapacitors and DC/DC converters). The tool allows the user to plug and play different pre characterized devices as well as add user defined devices. The goal of this simulation tool is to predict the battery lifetime of a device and determine the scope for extension using ambient energy sources.
This work was part of a larger EU multi-partner project titled “Residential Retrofit assessment platform and demonstrations for near zero energy and CO2 emissions with optimum cost, health, comfort and environmental quality” (ReCO2ST). The ReCO2ST project has received funding from the European Union’s “Horizon 2020” research and innovation programme under the grant agreement No. 768576
Development of Novel Acyl Thiol-ene Mediated Peptide Ligation Strategies
No full textThis thesis, entitled Development of Novel Acyl Thiol-ene Mediated Peptide Ligation Strategies is composed of six chapters. Chapter 1 provides an introductory overview of the fields of amide synthesis and peptide ligation. Particular emphasis is given to the emergence of Native Chemical Ligation and the extended methodologies developed to further the reach of this powerful synthetic technique. The limitations of these approaches, with regards to thioester formation via thioesterification, are also described. In addition, Chapter 1 details the application of thiol-ene chemistries to the synthesis and derivatisation of biomolecules, with specific attention given to the extent of the reaction within the field of peptide chemistry. The use of the acyl thiol-ene reaction to synthesise thioesters in organic syntheses is also detailed, along with the established chemical methods to access peptide thioacids. Chapter 1 is concluded with a brief description of the work described in this thesis and the overarching aims of this work.
Chapter 2 details efforts to develop acyl thiol-ene mediated ligation strategies via the synthesis and investigation of auxiliary bearing dipeptide systems. Unsaturated auxiliaries affixed to amino acid side-chains or α-amino groups of native peptides would permit the rapid formation of peptidic thioesters via acyl thiol-ene addition of a peptide thioacid component. S-to-N acyl transfer of the resulting thioester and subsequent auxiliary cleavage would furnish native amide products. Unfortunately, none of the auxiliary systems investigated possessed the necessary balance of synthetic accessibility, acyl transfer reliability and reaction stability to prompt their insertion into larger systems.
Chapter 3 describes the synthesis of derivatives of unsaturated unnatural amino acids vinylglycine and L-3,4-didehydrovaline inspired by literature precedent. Significant synthetic optimisation was required in the case of L-3,4-didehydrovaline. Nonetheless, routes to access gram quantities of N-tert-butyloxycarbonyl protected vinylglycine and L-3,4-didehydrovaline are detailed. The synthesis of unsaturated dipeptides from these precursors and investigation of their reactivity towards acyl thiol-ene addition with a range of amino acid thioacids is outlined. S-to-N acyl transfer and subsequent derivatisation of thioesters to native tripeptide products is also demonstrated.
Chapter 4 details efforts to synthesise two fragments of the therapeutically valuable peptide human parathyroid hormone. The synthesis of unsaturated decapeptides bearing vinylglycine and L-3,4-didehydrovaline functionalities via solid phase peptide synthesis is described. Efforts to synthesise peptide thioacids through literature protocols are also detailed.
Chapter 5 concludes the work in this thesis and briefly outlines possible future work.
Chapter 6 describes the general experimental procedures employed in the course of this work and characterisation data of the compounds synthesised during the preparation of this thesis
Evolutionary Entrepreneurial Ecosystems: a Research Pathway
No full textThe recent widespread interest of policy in entrepreneurial ecosystems has been complemented by a burgeoning academic research output. This research to date may be broadly categorized as focusing on place, actors, governance, and evolution. Of these groupings, evolutionary processes have been paid least attention despite their centrality to a dynamic ecosystem phenomenon that evolves from an origin through processes of growth, adaptation, and resilience. To redress this imbalance, we frame a future research agenda on evolutionary processes of entrepreneurial ecosystems. Foremost amongst these are the competing lens for the evolutionary processes, the appropriate and evolving geographic scope and boundaries of the ecosystem, and the evolving visible or invisible modes of governance. Methodologically, we call for greater use of longitudinal studies of such evolutionary processes
Approaches to analysis of qualitative research data: a reflection on the manual and technological approaches
No full textThis paper addresses a gap in the literature by providing reflective and critical insights
into the experiences during two PhD qualitative studies, which adopted different
approaches to data analysis. We first consider how the two PhD studies unfolded before
discussing the motivations, challenges and benefits of choosing either a technological
(NVivo) or manual approach to qualitative data analysis. The paper contributes to the
limited literature which has explored the comparative experiences of those undertaking
qualitative data analysis using different approaches. It provides insights into how
researchers conduct qualitative data analysis, using different approaches and the lessons
learnt
Developing a competency framework for managers to address suicide risk in the workplace
No full textEmployee mental health, and in particular, suicide risks, are things that managers often do not feel comfortable in addressing, leading to lack of knowledge, awareness, and support within an organization. The purpose of this research was to investigate the competencies required by managers to enable them to effectively address suicide risks arising with employees. Suicide-related ideations are thought to be characterized by experiences of
burdensomeness and thwarted connectedness. Drawing on clinical, managerial, and adaptive performance competencies, we examined competencies related to creating meaningfulness (as a counter to burdensomeness) and addressing employee\u27s need for relatedness (as a counter to thwarted connectedness) in terms of how managers assist employees presenting with suicide-related ideations in the workplace. To investigate this and develop a competency framework, we conducted qualitative interviews with 18 managers, drawing on existing interview protocols of critical incidents and behavioral event interviews for the elicitation of competencies. Competencies in adaptive performance (and particularly crisis management) emerged as important for facilitating managers’ interactions with employees who may present with suicidality. This research provides a first step in developing resources to equip managers with the necessary competencies that are needed to deal with employ experiencing suicide-related ideations
(i.e. perceived burdensomeness and thwarted connectedness). The framework is
also useful as an initial step to support human resource development (HRD) professionals develop interventions such as training and/or mentoring programs
for managers to address this very important issu
Understanding intracellular nanoparticle trafficking fates through spatiotemporally resolved magnetic nanoparticle recovery
No full textThe field of nanomedicine has the potential to be a game-changer in global health, with possible applications in prevention, diagnostics, and therapeutics. However, despite extensive research focus and funding, the forecasted explosion of novel nanomedicines is yet to materialize. We believe that clinical translation is ultimately hampered by a lack of understanding of how nanoparticles really interact with biological systems. When placed in a biological environment, nanoparticles adsorb a biomolecular layer that defines their biological identity. The challenge for bionanoscience is therefore to understand the evolution of the interactions of the nanoparticle–biomolecules complex as the nanoparticle is trafficked through the intracellular environment. However, to progress on this route, scientists face major challenges associated with isolation of specific intracellular compartments for analysis, complicated by the diversity of trafficking events happening simultaneously and the lack of synchronization between individual events. In this perspective article, we reflect on how magnetic nanoparticles can help to tackle some of these challenges as part of an overall workflow and act as a useful platform to investigate the bionano interactions within the cell that contribute to this nanoscale decision making. We discuss both established and emerging techniques for the magnetic extraction of nanoparticles and how they can potentially be used as tools to study the intracellular journey of nanomaterials inside the cell, and their potential to probe nanoscale decision-making events. We outline the inherent limitations of these techniques when investigating particular bio-nano interactions along with proposed strategies to improve both specificity and resolution. We conclude by describing how the integration of magnetic nanoparticle recovery with sophisticated analysis at the single-particle level could be applied to resolve key questions for this field in the future.Irish Research CouncilScience Foundation Ireland -- replace defaultCeltic Advanced Life Science Innovation Network (CALIN)Ireland-Wales ProgrammeUCD School of Biomolecular and Biomedical Scienc
A Three-Dimensional Cell Culture Platform for Long Time-Scale Observations of Bio-Nano Interactions
No full textWe know surprisingly little about the long-term outcomes for nanomaterials interacting with organisms. To date, most of what we know is derived from in vivo studies that limit the range of materials studied and the scope of advanced molecular biology tools applied. Long-term in vitro nanoparticle studies are hampered by a lack of suitable models, as standard cell culture techniques present several drawbacks, while technical limitations render current three-dimensional (3D) cellular spheroid models less suited. Now, by controlling the kinetic processes of cell assembly and division in a non-Newtonian culture medium, we engineer reproducible cell clusters of controlled size and phenotype, leading to a convenient and flexible long-term 3D culture that allows nanoparticle studies over many weeks in an in vitro setting. We present applications of this model for the assessment of intracellular polymeric and silica nanoparticle persistence and found that hydrocarbon-based polymeric nanoparticles undergo no apparent degradation over long time periods with no obvious biological impact, while amorphous silica nanoparticles degrade at different rates over several weeks, depending on their synthesis method.Irish Research CouncilPrincess Nourah Bint Abdulrahman University Projec