Hyperglycaemia does not increase perfusion deficits after focal cerebral ischaemia in male Wistar rats

Background: Hyperglycaemia is associated with a worse outcome in acute ischaemic stroke patients; yet the pathophysiological mechanisms of hyperglycaemia-induced damage are poorly understood. We hypothesised that hyperglycaemia at the time of stroke onset exacerbates ischaemic brain damage by increasing the severity of the blood flow deficit. Methods: Adult, male Wistar rats were randomly assigned to receive vehicle or glucose solutions prior to permanent middle cerebral artery occlusion. Cerebral blood flow was assessed semi-quantitatively either 1 h after middle cerebral artery occlusion using 99mTc-D, L-hexamethylpropyleneamine oxime (99mTc-HMPAO) autoradiography or, in a separate study, using quantitative pseudo-continuous arterial spin labelling for 4 h after middle cerebral artery occlusion. Diffusion weighted imaging was performed alongside pseudo-continuous arterial spin labelling and acute lesion volumes calculated from apparent diffusion coefficient maps. Infarct volume was measured at 24 h using rapid acquisition with refocused echoes T2-weighted magnetic resonance imaging. Results: Glucose administration had no effect on the severity of ischaemia when assessed by either 99mTc-HMPAO autoradiography or pseudo-continuous arterial spin labelling perfusion imaging. In comparison to the vehicle group, apparent diffusion coefficient–derived lesion volume 2–4 h post-middle cerebral artery occlusion and infarct volume 24 h post-middle cerebral artery occlusion were significantly greater in the glucose group. Conclusions: Hyperglycaemia increased acute lesion and infarct volumes but there was no evidence that the acute blood flow deficit was exacerbated. The data reinforce the conclusion that the detrimental effects of hyperglycaemia are rapid, and that treatment of post-stroke hyperglycaemia in the acute period is essential but the mechanisms of hyperglycaemia-induced harm remain unclear

How policy actors assert authority in the governance of food marketing policies

The regulation of unhealthy food marketing is a highly contested space that involves a diverse range of actors and institutions. There is a paucity of research on the strategies used by the different actors to influence these policies. This study examined the use of authority by different regulatory actors to influence food marketing policies. We conducted semi-structured interviews with (N = 24) government, industry, civil society and technical experts involved in the regulation of food and beverage marketing in Australia. We identified five types of authority: institutional, delegated, expert, principled and capacity-based authority. Actors from the advertising, food and media industries claim more authority than technical experts, civil society, and government actors, suggesting that industry actors have multiple pathways to influence policy. The industry's claims of delegated and institutional authority are highly contested by civil society, technical experts, and state/territory government actors and recognised by federal government actors. Claims of circumscribed institutional authority are common among federal government actors such as the National Department of Health, Australian Media and Communications Authority and Food Standards Australia New Zealand. The assertions of authority observed in this study highlight the fragmented manner of the Australian food marketing regulatory system and have implications for which actors should be held accountable for the current challenges in the governance of food marketing policies.</p

Reassessing the health impacts of trade and investment agreements: a systematic review of quantitative studies, 2016–20

To ensure a high level of health protection, governments must ensure that health and trade policy objectives are aligned. We conducted a systematic review of the health impacts of trade policies, including trade and investment agreements (TIAs), to provide a timely overview of this field. We systematically reviewed studies evaluating the health impacts of trade policies published between Jan 19, 2016, and July 10, 2020. Included studies were quantitative studies evaluating the impact of TIAs and trade policies on health determinants or outcomes. We evaluated methodological quality and performed a narrative synthesis. 21 of 28 067 articles identified via searches met our criteria. Methodologically strong studies found reduced child mortality, deteriorating worker health, rising supplies of sugar, ultra-processed food, tobacco, and alcohol supplies, and increased drug overdoses following trade reforms, compared with the time periods before trade reform. However, associations varied substantially across contexts and socioeconomic characteristics. Our findings show that trade policies, including TIAs, have diverse effects on health and health determinants. These effects vary substantially across contexts and socioeconomic groups. Governments seeking to adopt healthy trade policies should consider these updated findings to ensure that opportunities for health improvement are leveraged and widely shared, while harms are avoided, especially among vulnerable groups

Monitoring the impacts of trade agreements on food environments

The liberalization of international trade and foreign direct investment through multilateral, regional and bilateral agreements has had profound implications for the structure and nature of food systems, and therefore, for the availability, nutritional quality, accessibility, price and promotion of foods in different locations. Public health attention has only relatively recently turned to the links between trade and investment agreements, diets and health, and there is currently no systematic monitoring of this area. This paper reviews the available evidence on the links between trade agreements, food environments and diets from an obesity and non-communicable disease (NCD) perspective. Based on the key issues identified through the review, the paper outlines an approach for monitoring the potential impact of trade agreements on food environments and obesity/NCD risks. The proposed monitoring approach encompasses a set of guiding principles, recommended procedures for data collection and analysis, and quantifiable ‘minimal’, ‘expanded’ and ‘optimal’ measurement indicators to be tailored to national priorities, capacity and resources. Formal risk assessment processes of existing and evolving trade and investment agreements, which focus on their impacts on food environments will help inform the development of healthy trade policy, strengthen domestic nutrition and health policy space and ultimately protect population nutrition.The following organizations provided funding support for the travel of participants to Italy for this meeting and the preparation of background research papers: The Rockefeller Foundation, International Obesity Taskforce (IOTF), University of Auckland, Deakin University, The George Institute, University of Sydney, Queensland University of Technology, University of Oxford, University of Pennsylvania Perelman School of Medicine, World Cancer Research Fund International, University of Toronto, and The Australian National University. The Faculty of Health at Deakin University kindly supported the costs for open access availability of this paper, and the Australian National Health and Medical Research Council Centre for Research Excellence in Obesity Policy and Food Systems (APP1041020) supported the coordination and finalizing of INFORMAS manuscripts

Exchange bias between van der Waals materials: tilted magnetic states and field-free spin-orbit-torque switching

Magnetic van der Waals heterostructures provide a unique platform to study magnetism and spintronics device concepts in the two-dimensional limit. Here, we report studies of exchange bias from the van der Waals antiferromagnet CrSBr acting on the van der Waals ferromagnet Fe3GeTe2 (FGT). The orientation of the exchange bias is along the in-plane easy axis of CrSBr, perpendicular to the out-of-plane anisotropy of the FGT, inducing a strongly tilted magnetic configuration in the FGT. Furthermore, the in-plane exchange bias provides sufficient symmetry breaking to allow deterministic spin-orbit torque switching of the FGT in CrSBr/FGT/Pt samples at zero applied magnetic field. A minimum thickness of the CrSBr greater than 10 nm is needed to provide a non-zero exchange bias at 30 K

The potential for land sparing to offset greenhouse gas emissions from agriculture

Greenhouse gas emissions from global agriculture are increasing at around 1% per annum, yet substantial cuts in emissions are needed across all sectors. The challenge of reducing agricultural emissions is particularly acute, because the reductions achievable by changing farming practices are limited and are hampered by rapidly rising food demand. Here we assess the technical mitigation potential offered by land sparing-increasing agricultural yields, reducing farm land area and actively restoring natural habitats on the land spared. Restored habitats can sequester carbon and can offset emissions from agriculture. Using the United Kingdom as an example, we estimate net emissions in 2050 under a range of future agricultural scenarios. We find that a land-sparing strategy has the technical potential to achieve significant reductions in net emissions from agriculture and land-use change. Coupling land sparing with demand-side strategies to reduce meat consumption and food waste can further increase the technical mitigation potential, however economic and implementation considerations might limit the degree to which this technical potential could be realised in practice.This research was funded by the Cambridge Conservation Initiative Collaborative Fund for Conservation and we thank its major sponsor Arcadia. We thank J. Bruinsma for the provision of demand data, the CEH for the provision of soil data and J. Spencer for invaluable discussions. A.L. was supported by a Gates Cambridge Scholarship.This is the author accepted manuscript. The final version is available from Nature Publishing Group via http://dx.doi.org/10.1038/nclimate291