Adrift: Attribution & Responsibility in a Changing Climate

What if we could witness our own contribution to the warming climate? And how do we know if we’re seeing the "fingerprints" of anthropogenic global warming on an event? Climate change event attribution is a relatively new field of enquiry. Borrowing a formula from climate scientists Notz & Stroeve, visual artist and PhD student Adam Sébire describes how he was able to calculate and saw off exactly the amount of Greenlandic sea-ice that would be destroyed by his carbon emissions flying economy return from Sydney to document it. The multiscreen video artwork created, AnthropoScene IV: Adrift (∆Asea-ice) (2019) touches upon the disconnects that underly our psychological response to climate change

La gestion des espèces végétales exotiques envahissantes prioritaires dans les municipalités de l’Estrie

L’objectif de cet essai est de déterminer quelles méthodes de lutte devraient être privilégiées par les municipalités de l’Estrie pour contrer les espèces végétales exotiques envahissantes prioritaires. L’accroissement du commerce international a permis l’introduction de ces plantes au Canada, tandis que leur propagation locale est assurée par le réseau routier et les activités récréotouristiques. Les espèces végétales exotiques envahissantes sont désormais très présentes en Estrie et engendrent d’importants dommages tels que les pertes de biodiversité, de rendements agricoles, de valeurs des propriétés et d’attraits récréotouristiques. Le manque de ressources et de prise de conscience de la gravité de cette problématique par les municipalités de l’Estrie est à l’origine de l’élaboration de ce document. L’analyse de l’abondance et des impacts des espèces végétales exotiques envahissantes de l’Estrie démontre que le roseau commun (Phragmites australis), la renouée du Japon (Fallopia japonica), le nerprun bourdaine (Frangula alnus) et le myriophylle à épis (Myriopyllum spicatum) constituent les quatre espèces prioritaires. Par ailleurs, les résultats indiquent que les méthodes préventives de lutte à privilégier sont l’ensemencement des sols mis à nu, l’inspection visuelle des embarcations, la sensibilisation et une gestion appropriée de l’entretien des emprises routières. Concernant les méthodes de contrôle et d’éradication, la couverture végétale et l’ombrage obtiennent la meilleure note, suivies par l’application d’herbicide par contact et enfin, à égalité, le fauchage, l’arrachage et la toile de jute immergée. La mise en place de toutes les méthodes préventives mentionnées ci-dessus est fortement recommandée aux municipalités, contrairement aux postes de lavage. Le contrôle des jeunes colonies d’espèces végétales exotiques envahissantes doit privilégier la couverture végétale et l’ombrage, ainsi que l’arrachage en milieu terrestre et la toile de jute en milieu aquatique. Le fauchage permet de contrôler de vastes colonies terrestres bien établies, alors que l’herbicide doit être utilisé en dernier recours pour une éradication rapide en milieu terrestre. Enfin, un suivi des méthodes mises en place est nécessaire

Developmental regulation of the neuroinflammatory responses to LPS and/or hypoxia-ischemia between preterm and term neonates: An experimental study

<p>Abstract</p> <p>Background</p> <p>Preterm and term newborns are at high risk of brain damage as well as subsequent cerebral palsy and learning disabilities. Indeed, hypoxia-ischemia (HI), pathogen exposures, and associated intracerebral increase of pro-inflammatory cytokines have all been linked to perinatal brain damage. However, the developmental effects of potential variations of pro- and anti-inflammatory cytokine ratios remain unknown.</p> <p>Methods</p> <p>Using rat models of perinatal brain damage induced by exposures to lipopolysaccharide (LPS) and/or HI at distinct levels of maturity, we compared cytokine expression at stages of cerebral development equivalent to either preterm (postnatal day 1, P1) or term (P12) newborns.</p> <p>Results</p> <p>At P1, expression of anti-inflammatory cytokine within the brain was either not modulated (IL-6, IL-10) or down-regulated (IL-1ra, TGF-β1) by HI, LPS or LPS+HI. In contrast, there was at P12 an up-regulation of all anti-inflammatory cytokines studied in HI or LPS+HI condition, but not after LPS exposure. Interestingly, IL-1β was the main pro-inflammatory cytokine up-regulated moderately at P1, and strongly at P12, with a weak co-expression of TNF-α observed mainly at P12. These age-dependant inflammatory reactions were also accompanied, under HI and LPS+HI conditions, at P12 only, by combined: (i) expression of chemokines CINC-1 and MCP-1, (ii) blood-brain barrier (BBB) leakage, and (iii) intracerebral recruitment of systemic immune cells such as neutrophils. In contrast, sole LPS induced IL-1β responses mainly within white matter at P1 and mainly within gray matter at P12, that were only associated with early MCP-1 (but no CINC-1) induction at both ages, without any recruitment of neutrophils and CD68+ cells.</p> <p>Conclusion</p> <p>HI and LPS+HI induce pro-inflammatory oriented immune responses in both preterm and term like brains, with a maximal inflammatory response triggered by the combination of LPS+HI. The profile of these neuroinflammatory responses presented striking variations according to age: no or down-regulated anti-inflammatory responses associated with mainly IL-1β release in preterm-like brains (P1), in sharp contrast to term-like brains (P12) presenting stronger anti-and pro-inflammatory responses, including both IL-1β and TNF-α releases, and BBB leakage. These developmental-dependant variations of neuroinflammatory response could contribute to the differential pattern of brain lesions observed across gestational ages in humans. This also highlights the necessity to take into consideration the maturation stage, of both brain and immune systems, in order to develop new anti-inflammatory neuroprotective strategies.</p

Impact of ACK/NACK Signalling Errors on High Speed Uplink Packet Access (HSUPA)

Abstract -In this paper, the impact of signalling errors on the performance of High Speed Uplink Packet Access (HSUPA) in soft handover (SHO) is investigated. The signalling discussed here is the one related to HARQ operation: acknowledgements (ACK) and negative acknowledgements (NACK) in the downlink. Through simulations, it is shown how ACK/NACK signalling errors affect the throughput in both soft handover and non-soft handover cases

HANDLING MULTILINGUAL CONTENT IN DIGITAL MEDIA: A CRITICAL ANALYSIS

This document expresses and analyzes the need to define a generic method for representing multilingual information in multimedia data. It describes the basic requirements that would bear upon such representations and establishes the potential link with ISO committee TC 37/SC 4 (Language Resource Management) and with XMT (eXtended MPEG-4 Textual format)

Trazodone regulates neurotrophic/growth factors, mitogen-activated protein kinases and lactate release in human primary astrocytes

Background: In the central nervous system, glial cells provide metabolic and trophic support to neurons and respond to protracted stress and insults by up-regulating inflammatory processes. Reactive astrocytes and microglia are associated with the pathophysiology of neuronal injury, neurodegenerative diseases and major depression, in both animal models and human brains. Several studies have reported clear anti-inflammatory effects of anti-depressant treatment on astrocytes, especially in models of neurological disorders. Trazodone (TDZ) is a triazolopyridine derivative that is structurally unrelated to other major classes of antidepressants. Although the molecular mechanisms of TDZ in neurons have been investigated, it is unclear whether astrocytes are also a TDZ target. Methods: The effects of TDZ on human astrocytes were investigated in physiological conditions and following inflammatory insult with lipopolysaccharide (LPS) and tumour necrosis factor-aα (TNF-aα). Astrocytes were assessed for their responses to pro-inflammatory mediators and cytokines, and the receptors and signalling pathways involved in TDZ-mediated effects were evaluated. Results: TDZ had no effect on cell proliferation, but it decreased pro-inflammatory mediator release and modulated trophic and transcription factor mRNA expression. Following TDZ treatment, the AKT pathway was activated, whereas extracellular signal-regulated kinase and c-Jun NH2-terminal kinase were inhibited. Most importantly, a 72-h TDZ pre-treatment before inflammatory insult completely reversed the anti-proliferative effects induced by LPS-TNF-aα. The expression or the activity of inflammatory mediators, including interleukin-6, c-Jun NH2-terminal kinase and nuclear factor ΚB, were also reduced. Furthermore, TDZ affected astrocyte metabolic support to neurons by counteracting the inflammation-mediated lactate decrease. Finally, TDZ protected neuronal-like cells against neurotoxicity mediated by activated astrocytes. These effects mainly involved an activation of 5-HT1A and an antagonism at 5-HT2A/C serotonin receptors. Fluoxetine, used in parallel, showed similar final effects nevertheless it activates different receptors/intracellular pathways. Conclusions: Altogether, our results demonstrated that TDZ directly acts on astrocytes by regulating intracellular signalling pathways and increasing specific astrocyte-derived neurotrophic factor expression and lactate release. TDZ may contribute to neuronal support by normalizing trophic and metabolic support during neuroinflammation, which is associated with neurological diseases, including major depression