Spectacular Imaginations of the Sinking Island

As entire island nations slip beneath rising seas, how can we reimagine a political future where the effects of climate change are already in full force? In recent years, it has become increasingly apparent that there is a fundamental lack of legal protections for those fleeing environmental degradation and the effects of global sea level rise. This lack of protection is felt particularly strongly in the Pacific region, where many communities are faced with existential threats to their way of life and self-determination. However, despite this historic lack of support from the international community, the Pacific Islands states have continuously pushed their climate-forward agenda in debates leading up to the landmark 2015 Paris Accords, even going so far as earning themselves multiple mentions in the text of the Accords. In January of 2020, Pacific actors even pressured a landmark UN decision granting international protection to a new class of “climate refugees”--a distinction that had no legal value until this monumental agreement. How did such tiny, geo-politically distant actors create such dramatic movement in a global forum dominated by industrial superpowers? The answer to this puzzle lies within the creative, multifaceted, and sometimes bizarre strategies of Pacific Island leaders in gaining international attention and sympathy towards their cause. Through a collaboration between state and non-state actors, these Pacific Island delegates effectively pushed their climate agenda with a variety of different tactics; namely the dramatic and spectacular performances of Pacific diplomats and the direct incorporation of NGOs into international debate. The case of Pacific Island climate diplomacy challenges our assumptions about the roles of small nation states, grassroots advocacy groups, and media outlets, all while effectively redefining what it means to be a “victim” of global climate change

Influence of polar co-solutes and salt on the hydration of lipid membranes

The influence of the co-solutes TMAO, urea, and NaCl on the hydration repulsion between lipid membranes is investigated in a combined experimental/simulation approach. Pressure–hydration curves obtained via sorption experiments reveal that the repulsion significantly increases when the membranes are loaded with co-solutes, most strongly for TMAO. As a result, the co-solutes retain additional water molecules and therefore provide membranes with a fluid and more physiological environment. The experimental data are quantitatively reproduced in complementary solvent-explicit atomistic molecular dynamics simulations, which yield the chemical potential of water. Simulation analysis reveals that the additional repulsion arises from the osmotic pressure generated by the co-solutes, an effect which is maximal for TMAO, due to its unfavorable interactions with the lipid headgroup layer and its extraordinarily high osmotic coefficient

Effects of Urea and TMAO on Lipid Self-Assembly under Osmotic Stress Conditions

Most land-living organisms regularly experience dehydration. In nature, one commonly applied strategy to protect against this osmotic stress is to introduce small polar molecules with low vapor pressure, commonly called osmolytes. Two examples of naturally occurring small polar compounds are urea and trimethylamine N-oxide (TMAO), which are known to have counteracting effects on protein stability. In this work, we investigate the effects of urea and TMAO on lipid self-assembly at varying water contents, focusing on dehydrated conditions. By using complementary experimental techniques, including sorption microcalorimetry, NMR, and X-ray scattering, together with molecular dynamics simulations in model systems composed of phosphatidylcholine lipids, water, and solute, we characterize interactions and self-assembly over a large range of hydration conditions. It is shown that urea and TMAO show qualitatively similar effects on lipid self-assembly at high water contents, whereas they have clearly different effects in dehydrated conditions. The latter can be explained by differences in the molecular interactions between the solutes and the lipid headgroups. TMAO is repelled from the bilayer interface, and it is thereby expelled from lipid lamellar systems with low water contents and narrow inter-bilayer regions. In these conditions, TMAO shows no effect on the lipid phase behavior. Urea, on the other hand, shows a slight affinity for the lipid headgroup layer, and it is present in the lipid lamellar system at all water contents. As a result, urea may exchange with water in dry conditions and thereby prevent dehydration-induced phase transitions. In nature, urea and TMAO are sometimes found together in the same organisms and it is possible that their combined effect is to both protect lipid membranes against dehydration and still avoid denaturation of proteins

Multivariate lesion symptom mapping for predicting trajectories of recovery from aphasia.

Individuals with post-stroke aphasia tend to recover their language to some extent; however, it remains challenging to reliably predict the nature and extent of recovery that will occur in the long term. The aim of this study was to quantitatively predict language outcomes in the first year of recovery from aphasia across multiple domains of language and at multiple timepoints post-stroke. We recruited 217 patients with aphasia following acute left hemisphere ischaemic or haemorrhagic stroke and evaluated their speech and language function using the Quick Aphasia Battery acutely and then acquired longitudinal follow-up data at up to three timepoints post-stroke: 1 month (n = 102), 3 months (n = 98) and 1 year (n = 74). We used support vector regression to predict language outcomes at each timepoint using acute clinical imaging data, demographic variables and initial aphasia severity as input. We found that ∼60% of the variance in long-term (1 year) aphasia severity could be predicted using these models, with detailed information about lesion location importantly contributing to these predictions. Predictions at the 1- and 3-month timepoints were somewhat less accurate based on lesion location alone, but reached comparable accuracy to predictions at the 1-year timepoint when initial aphasia severity was included in the models. Specific subdomains of language besides overall severity were predicted with varying but often similar degrees of accuracy. Our findings demonstrate the feasibility of using support vector regression models with leave-one-out cross-validation to make personalized predictions about long-term recovery from aphasia and provide a valuable neuroanatomical baseline upon which to build future models incorporating information beyond neuroanatomical and demographic predictors

Effects of Urea and TMAO on Lipid Self-Assembly under Osmotic Stress Conditions

Most land-living organisms regularly experience dehydration. In nature, one commonly applied strategy to protect against this osmotic stress is to introduce small polar molecules with low vapor pressure, commonly called osmolytes. Two examples of naturally occurring small polar compounds are urea and trimethylamine <i>N</i>-oxide (TMAO), which are known to have counteracting effects on protein stability. In this work, we investigate the effects of urea and TMAO on lipid self-assembly at varying water contents, focusing on dehydrated conditions. By using complementary experimental techniques, including sorption microcalorimetry, NMR, and X-ray scattering, together with molecular dynamics simulations in model systems composed of phosphatidylcholine lipids, water, and solute, we characterize interactions and self-assembly over a large range of hydration conditions. It is shown that urea and TMAO show qualitatively similar effects on lipid self-assembly at high water contents, whereas they have clearly different effects in dehydrated conditions. The latter can be explained by differences in the molecular interactions between the solutes and the lipid headgroups. TMAO is repelled from the bilayer interface, and it is thereby expelled from lipid lamellar systems with low water contents and narrow inter-bilayer regions. In these conditions, TMAO shows no effect on the lipid phase behavior. Urea, on the other hand, shows a slight affinity for the lipid headgroup layer, and it is present in the lipid lamellar system at all water contents. As a result, urea may exchange with water in dry conditions and thereby prevent dehydration-induced phase transitions. In nature, urea and TMAO are sometimes found together in the same organisms and it is possible that their combined effect is to both protect lipid membranes against dehydration and still avoid denaturation of proteins

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population.The aim of this study was to inform vaccination prioritization by modelling the impact of vaccination on elective inpatient surgery. The study found that patients aged at least 70 years needing elective surgery should be prioritized alongside other high-risk groups during early vaccination programmes. Once vaccines are rolled out to younger populations, prioritizing surgical patients is advantageous