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China produces over 200 tonnes of rice straw (RS) a year. This is an underutilized energy source that is often burned in the fields causing pollution and health problems for populations near and far. Anaerobic digestion (AD) can produce methane (CH 4 ) rich biogas (45-55%) from waste RS as an alternative to burning whilst being affordable. Five 2L reactors were used to test the effect of feeding frequency (FF) and organic loading rates (OLR) on the anaerobic digestion of rice straw with input rates of between 5 feeds per week and one feed every 3 weeks. Two OLRs were used: 1gVS/L/d (OLR1) for 56 days and 2gVS/L/d (OLR2) for 83 days. At the lower OLR1, the best average biogas yield was 300 ml/L of reactor/d at 50% CH 4 and at OLR2 the best reactor achieved a mean biogas yield of 447 ml/L/d at 52%CH 4 . The best performing FF at OLR1 was 1/21 day whilst at OLR2 the 5/7 day FF produced the highest volume and quality of biogas. Results confirm that biogas from rice straw anaerobic digestion could be used with combined heat and power (CHP) technology to potentially produce 0.5-0.8MWh of electricity per day per tonne of rice straw. [ABSTRACT FROM AUTHOR]

Introduction: Medical imaging is integrated across all years in the medical programs at the Medical School, in our country. Little is known about this pedagogical approach from the perspective of those who participate in it. This study investigated how students and educators experience an integrated medical imaging curriculum., Methods: One-on-one interviews were conducted with nine educators and three undergraduate medical students and analyzed using a reflexive thematic approach. Educators included radiologists, non-radiologists clinicians, and scientists and health professionals from the medical program., Results: The integrated medical imaging curriculum appears to be incoherently experienced by educators and students as learning opportunities that were 'everywhere and nowhere'. Teaching events were 'repetitive and patchy' and featured a transmission-oriented pedagogy emphasizing 'exposure and absorption'. Educators expressed paradoxical views of their responsibility for teaching medical imaging reflected in this sentiment: 'I don't teach medical imaging… (but I do)'., Discussion: When medical imaging is integrated into learning resources and course work across the undergraduate program, it may lose its visibility and importance as a distinct learning area despite its crucial role in medical practice. An integrated curriculum may inadvertently separate knowing about medical imaging from learning to apply medical imaging knowledge in clinical practice., Conclusions: Further work is required to construct an integrated medical imaging curriculum that explicitly emphasizes medical imaging learning outcomes, so they are experienced coherently and consistently by medical students and those who prepare them for practice as doctors., (Copyright © 2022 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

Background and Purpose- Over 80% of ischemic stroke patients show an abrupt increase in arterial blood pressure in the hours and days following ischemic stroke. Whether this poststroke hypertension is beneficial or harmful remains controversial and the underlying physiological basis is unclear. Methods- To investigate the dynamic cardiovascular response to stroke, adult Wistar rats (n=5-8 per group, 393±34 g) were instrumented with telemeters to blood pressure, intracranial pressure, renal sympathetic nerve activity, and brain tissue oxygen in the predicted penumbra (Po 2 ). After 2 weeks of recovery, cardiovascular signals were recorded for a 3-day baseline period, then ischemic stroke was induced via transient middle cerebral artery occlusion, or sham surgery. Cardiovascular signals were then recorded for a further 10 days, and the functional sensorimotor recovery assessed using the cylinder and sticky dot tests. Results- Baseline values of all variables were similar between groups. Compared to sham, in the 2 days following stroke middle cerebral artery occlusion produced an immediate, transient rise above baseline in mean blood pressure (21±3 versus 2±4 mm Hg; P<0.001), renal sympathetic nerve activity (54±11% versus 7±4%; P=0.006), and cerebral perfusion pressure (12±5 versus 1±4; P≤0.001). Intracranial pressure increased more slowly, peaking 3 days after middle cerebral artery occlusion (14±6 versus -1±1 mm Hg; P<0.001). Treating with the antihypertensive agent nifedipine after stroke (1.5-0.75 mg/kg per hour SC) ameliorated poststroke hypertension (12±3 mm Hg on day 1; P=0.041), abolished the intracranial pressure increase (3±1; P<0.001) and reduced cerebral perfusion pressure (10±3 mm Hg; P=0.017). Preventing poststroke hypertension affected neither the recovery of sensorimotor function nor infarct size. Conclusions- These findings suggest that poststroke hypertension is immediate, temporally matched to an increase in sympathetic outflow, and elevates cerebral perfusion pressure for several days after stroke, which may enhance cerebral perfusion. Preventing poststroke hypertension does not appear to worsen prognosis after stroke in young, normotensive, and otherwise healthy rats. Visual Overview- An online visual overview is available for this article.