Promoting physical activity and reducing climate change : Opportunities to replace short car trips with active transportation

Peer reviewedPostprin

Ischemia monitoring after aneurysmal subarachnoid haemorrhage; contribution of brain tissue oxygen and cerebral microdialysis monitoring

Introduction: Delayed cerebral ischemia (DCI) is a frequent and serious complication of aneurysmal subarachnoid haemorrhage (SAH). The diagnosis of DCI lies primarily on the deterioration of the clinical state (neurological deficit), but can be difficult to detect in the comatose patient. Transcranial Dopper (TCD) and perfusion Computer Tomography with calculation of cerebral blood flow (CBF) and brain perfusion help with the diagnosis of DCI but their predictive values remain limited. The DCI mechanisms are complex, involving alteration of CBF, impaired cerebral autoregulation, brain energy dysfunction and activation of pro-inflammatory mediators. The use of novel techniques for advanced intracranial monitoring (including brain tissue PO2 and cerebral microdialysis) offer the opportunity to study in detail DCI physiopathology and might help detecting DCI and guiding therapeutic interventions in patients suffering from SAH. General objectives: The main objective of this study was to examine the relationship between global CBF - measured with TCD and perfusion-CT - and regional brain metabolism, measured with the brain tissue oxygen (PbtO2) probe and the cerebral microdialysis (CMD) technique. Specific objectives: To examine the relationship between: - DCI and the brain tissue oxygen pressure reactivity index (ORx), which is calculated as the moving linear correlation coefficient between PbtO2 and CPP (=mean arterial pressure - intracranial pressure). The ORx is considered as a surrogate marker of the cerebral autoregulation state; - ORx and CBF, calculated with the perfusion-CT; - ORx and CMD markers of brain energy metabolism (including the lactate/pyruvate ratio and glucose). Methods: Retrospective analysis of an ongoing cohort database of patients with coma (defined by a Glasgow Coma Scale (GCS) ≤ 8) after aneurysmal SAH, with an abnormal CT-scan (Fisher grade II-IV), who underwent intracranial monitoring with PbtO2 and CMD as part of standard care. Intracranial monitoring was inserted after admission (2 ±1 days). A total of 21 patients were admitted in the Intensive Care Department with poor-grade SAH and underwent imaging and aneurysm securisation (with surgical clipping or endovascular coiling). Cerebral microdialysis allows to measure every hour, through a catheter placed in the cerebral parenchyma (white matter), the extracellular concentration of the main brain metabolites (glucose, lactate, pyruvate, lactate/pyruvate ratio). The DCI is diagnosed with the TCD and the perfusion-CT. The CBF (derived from the cerebral blood volume and the mean transit time) was calculated with the perfusion-CT, with a CBF < 32ml/100g/min that was used as the threshold for brain oligemia. Brain cell hypoxia was defined as a PbtO2 <20mmHg and/or a CMD lactate/pyruvate-ratio >40. The different variables were compared by univariate analysis using a Wilcoxon test for comparisons. The relationship between variables was analysed with the Pearson's R linear correlation coefficient factor. Expected results: From a clinical standpoint, if a relationship between regional brain physiological variables and global cerebral blood flow can be demonstrated, this could serve as a validation of PbtO2 and cerebral microdialysis monitoring as complementary tools for the diagnosis and the management of DCI in comatose SAH patients. From a pathophysiological standpoint, this study will provide new insights concerning the relationship between cerebral blood flow, brain oxygenation and cerebral energy metabolism in the acute phase of SAH

Conductors and Rings with Shared Ideals

Given an additive subgroup $I$ of a field $K$, we define the colon ideal (I:I) = {\alpha \in K: \alpha I \subseteq I}. We then use this to construct collections of rings with shared ideals and explore relationships between these concepts and the complete integral closure

Using social science in National Park Service climate communications: A case study in the National Capital Region

Since 2012, the National Park Service’s (NPS’s) Urban Ecology Research Learning Alliance (UERLA) and George Mason University’s Center for Climate Change Communication have partnered on a collaborative “research-to-practice” internship program that employs undergraduate and graduate-level students to produce interdisciplinary, science-based climate change communication products for parks in the NPS National Capital Region (NCR). Materials created through this program are rooted in social science insights (e.g., trusted sources, social norms, place-based learning), climate science, and the communication needs of participating regional parks. As a result, the end products (e.g. websites, videos, ranger toolkits) produced by this program fulfill many functions: increasing public awareness of climate impacts on park resources, nurturing the connection between people and places, meeting evolving interpretation demands by developing material for a variety of channels, effectively engaging visitors in climate dialogue, and helping parks lead by example by addressing how a changing climate can alter cultural, natural, historical, and recreational resources. The success, adaptability, and longevity of this program have provided NCR parks with a wealth of innovative products that support the park stewardship mission to preserve resources for future generations. Five examples will demonstrate the breadth of work undertaken by interns

Americans’ Global Warming Beliefs and Attitudes

This report presents results from a national study of what Americans understand about how the climate system works, and the causes, impacts, and potential solutions to global warming. Among other findings, the study identifies a number of important gaps in public knowledge and common misconceptions about climate change. Educational levels: Graduate or professional, Undergraduate upper division, Undergraduate lower division, General public

Inactive materials matter: How binder amounts affect the cycle life of graphite electrodes in potassium-ion batteries

Recent results on the intercalation of potassium into graphite suggest that graphite might become yet again a negative electrode material of choice for an alkali-ion battery system. Compared to its mature application state in Li-ion batteries, graphite for K-ion applications is still in an early development stage. Although cycling of graphite-potassium half-cells over 200 cycles has been demonstrated, the electrodes clearly suffer from more severe capacity fading, as compared to the corresponding Li system. This study demonstrates that the capacity fade is strongly linked to the binder content in the composite electrode. High binder contents of 8 wt% (this study) or more (literature) show significant cycle life improvements over electrodes comprising of more practical binder contents of 4 wt% or less. The results highlight the need for revised or entirely new strategies to control the formation and stability of the electrode–electrolyte interphase in K-ion batteries

The Effect of Perfusion Rate on In Vitro Percutaneous Penetration**From the Division of Dermatology, University of California School of Medicine, San Francisco, California 94122.

This study presents data on the effect of varying dermal perfusion rates in an in vitro chamber on percutaneous penetration. Increasing the perfusion flow rates significantly increases the penetration rate with the compounds studied. This suggests that the data obtained in in vitro studies will be more meaningful when ideal flow rates are determined for such chambers and validated with in vivo data

Topological Dark Matter in LIGO Data

In the efforts of searching for dark matter, gravitational wave interferometers have been recently proposed as a promising probe. These highly sensitive instruments are potentially be able to detect the interactions of dark matter with the detectors. In this work, we explored the possibilities of discovering topological dark matter with LIGO detectors. We analyzed domain walls consisting of axion-like dark matter passing through Earth, leaving traces in multiple detectors simultaneously. Considering dark matter interactions with the light in the interferometer and with the beamsplitter, we performed the first analysis of the topological dark matter with the gravitational-wave strain data. We examined whether astrophysically unexpected triggers could be explained by domain wall passages. We found that all of the binary black hole mergers we analyzed favored the binary black hole merger hypothesis rather than the domain wall hypothesis, with the closest being GW190521. Moreover we found that some of topological dark matter signals can be caught by binary black hole searches. Finally, we found that glitches in the data can inevitably limit the dark matter searches for certain parameters. These results are expected to guide the future searches and analyses.Comment: 13 pages with 12 figures. Comments are welcom