Upcycling plastic waste into fully recyclable composites through cold sintering.

Plastics have substantial societal benefits, but their widespread use has led to a critical waste management challenge. While mechanical recycling dominates the reuse of post-consumer plastics, it is limited in efficacy, especially for composites. To address this, we propose a direct reprocessing approach that enables the creation of hybrid, long-lasting, and durable composites from difficult-to-recycle plastics. This approach utilizes cold sintering, a process that consolidates inorganic powders through fractional dissolution and precipitation at temperatures far below conventional sintering; these temperatures are compatible with plastic processing. We show that this process can create inorganic-matrix composites with significant enhancements in tensile strength and toughness over pure gypsum, which is commonly found in construction waste. These composites can be recycled multiple times through direct reprocessing with the addition of only water as a processing promoter. This approach to recycling leads to composites with orders of magnitude lower energy demand, global warming potential, and water demand, when compared against common construction products. Altogether, we demonstrate the potential for cold sintering to integrate waste into high-performance recyclable composites.

Cold Sintering Enables the Reprocessing of LLZO-Based Composites.

All-solid-state batteries have the potential for enhanced safety and capacity over conventional lithium ion batteries, and are anticipated to dominate the energy storage industry. As such, strategies to enable recycling of the individual components are crucial to minimize waste and prevent health and environmental harm. Here, we use cold sintering to reprocess solid-state composite electrolytes, specifically Mg and Sr doped Li7 La3 Zr2 O12 with polypropylene carbonate (PPC) and lithium perchlorate (LLZO-PPC-LiClO4 ). The low sintering temperature allows co-sintering of ceramics, polymers and lithium salts, leading to re-densification of the composite structures with reprocessing. Reprocessed LLZO-PPC-LiClO4 exhibits densified microstructures with ionic conductivities exceeding 10-4  S/cm at room temperature after 5 recycling cycles. All-solid-state lithium batteries fabricated with reprocessed electrolytes exhibit a high discharge capacity of 168 mA h g-1 at 0.1 C, and retention of performance at 0.2 C for over 100 cycles. Life cycle assessment (LCA) suggests that recycled electrolytes outperforms the pristine electrolyte process in all environmental impact categories, highlighting cold sintering as a promising technology for recycling electrolytes.

Risk of acute kidney injury associated with neuroimaging obtained during triage and treatment of patients with acute ischemic stroke symptoms.

BACKGROUND: Combining non-contrast CT (NCCT), CT angiography (CTA), and CT perfusion (CTP) imaging (referred to as a CT stroke study, CTSS) provides a rapid evaluation of the cerebrovascular axis during acute ischemic stroke. Iodinated contrast-enhanced CT imaging is not without risk, which includes renal injury. If a patient's CTSS identifies vascular pathology, digital subtraction angiography (DSA) is often performed within 24-48 h. Such patients may receive multiple administrations of iodinated contrast material over a short time period. OBJECTIVE: We aimed to evaluate the incidence of acute kidney injury (AKI) in patients who underwent a CTSS and DSA for evaluation of acute ischemic symptoms or for stroke intervention within a 48 h period between August 2012 and December 2014. METHODS: We identified 84 patients for inclusion in the analysis. Patients fell into one of two cohorts: AKI, defined as a rise in the serum creatinine level of ≥0.5 mg/dL from baseline, or non-AKI. Clinical parameters included pre- and post-imaging serum creatinine level, time between CTSS and DSA, and type of angiographic procedure (diagnostic vs intervention) performed. RESULTS: Four patients (4.7%) experienced AKI, one of whom had baseline renal dysfunction (defined as baseline serum creatinine level ≥1.5 mg/dL). The mean difference between baseline and peak creatinine values was found to be significantly greater in patients with AKI than in non-AKI patients (1.65 vs -0.09, respectively; p=0.0008). CONCLUSIONS: This study provides preliminary evidence of the safety and feasibility of obtaining CTSS with additional DSA imaging, whether for diagnosis or intervention, to identify possible acute ischemic stroke.

To Treat or Not to Treat M2 Occlusions? The Question (and Answer) From a Single Institution.

BACKGROUND: Occlusions of the M2 segment of the middle cerebral artery may cause significant clinical effects, especially when occurring in the dominant cerebral hemisphere, yet endovascular treatment of these lesions remains controversial. OBJECTIVE: To examine the safety and efficacy of endovascular treatment of M2 occlusions at our institution. METHODS: We retrospectively examined radiographic and clinical data of 53 patients presenting with M2 occlusions to our institution. RESULTS: Successful recanalization (Thrombolysis in Cerebral Infarction grade 2b or 3) was achieved in 40 patients (76.9%). No symptomatic intracranial hemorrhage occurred. The mean National Institutes of Health Stroke Scale score at discharge was 6.4 (median, 5.5). In the 38 patients who had follow-up after discharge, the mean follow-up duration was 11.1 months (range, 0.5-36.5 months) and mean National Institutes of Health Stroke Scale score was 3.5 (median, 1). CONCLUSION: The results of our single-institution experience suggest that endovascular therapy for M2 occlusions is safe and effective. Additional evaluation with randomized, controlled studies is warranted. ABBREVIATIONS: ADAPT, direct aspiration first-pass techniqueECASS, European-Australasian Cooperative Acute Stroke StudyICH, intracranial hemorrhageIMS, Interventional Management of StrokeMERCI, Mechanical Embolus Removal in Cerebral IschemiamRS, modified Rankin ScaleNIHSS, National Institutes of Health Stroke ScalePROACT, Prolyse in Acute Cerebral ThromboembolismTICI, Thrombolysis in Cerebral Infarctiont-PA, tissue-type plasminogen activator.