Neutron Instruments for Research in Coordination Chemistry.

Neutron diffraction and spectroscopy offer unique insight into structures and properties of solids and molecular materials. All neutron instruments located at the various neutron sources are distinct, even if their designs are based on similar principles, and thus, they are usually less familiar to the community than commercial X-ray diffractometers and optical spectrometers. Major neutron instruments in the USA, which are open to scientists around the world, and examples of their use in coordination chemistry research are presented here, along with a list of similar instruments at main neutron facilities in other countries. The reader may easily and quickly find from this minireview an appropriate neutron instrument for research. The instruments include single-crystal and powder diffractometers to determine structures, inelastic neutron scattering (INS) spectrometers to probe magnetic and vibrational excitations, and quasielastic neutron scattering (QENS) spectrometers to study molecular dynamics such as methyl rotation on ligands. Key and unique features of the diffraction and neutron spectroscopy that are relevant to inorganic chemistry are reviewed.

Collaterals and stroke reperfusion: Too few leads to too much.

Adequate reperfusion after ischemic stroke is a major determinant of functional outcome yet remains unpredictable and insufficient for most survivors. In this issue of Neuron, Binder et al.1 identify leptomeningeal collaterals (LMCs) in mice and human patients as a key factor in regulating reperfusion and hemorrhagic transformation following stroke.

Effects of RBT-1 on preconditioning response biomarkers in patients undergoing coronary artery bypass graft or heart valve surgery: a multicentre, double-blind, randomised, placebo-controlled phase 2 trial.

Background: RBT-1 is a combination drug of stannic protoporfin (SnPP) and iron sucrose (FeS) that elicits a preconditioning response through activation of antioxidant, anti-inflammatory, and iron-scavenging pathways, as measured by heme oxygenase-1 (HO-1), interleukin-10 (IL-10), and ferritin, respectively. Our primary aim was to determine whether RBT-1 administered before surgery would safely and effectively elicit a preconditioning response in patients undergoing cardiac surgery. Methods: This phase 2, double-blind, randomised, placebo-controlled, parallel-group, adaptive trial, conducted in 19 centres across the USA, Canada, and Australia, enrolled patients scheduled to undergo non-emergent coronary artery bypass graft (CABG) and/or heart valve surgery with cardiopulmonary bypass. Patients were randomised (1:1:1) to receive either a single intravenous infusion of high-dose RBT-1 (90 mg SnPP/240 mg FeS), low-dose RBT-1 (45 mg SnPP/240 mg FeS), or placebo within 24-48 h before surgery. The primary outcome was a preoperative preconditioning response, measured by a composite of plasma HO-1, IL-10, and ferritin. Safety was assessed by adverse events and laboratory parameters. Prespecified adaptive criteria permitted early stopping and enrichment. This trial is registered with ClinicalTrials.gov, NCT04564833. Findings: Between Aug 4, 2021, and Nov 9, 2022, of 135 patients who were enrolled and randomly allocated to a study group (46 high-dose, 45 low-dose, 44 placebo), 132 (98%) were included in the primary analysis (46 high-dose, 42 low-dose, 44 placebo). At interim, the trial proceeded to full enrollment without enrichment. RBT-1 led to a greater preconditioning response than did placebo at high-dose (geometric least squares mean [GLSM] ratio, 3.58; 95% CI, 2.91-4.41; p < 0.0001) and low-dose (GLSM ratio, 2.62; 95% CI, 2.11-3.24; p < 0.0001). RBT-1 was generally well tolerated by patients. The primary drug-related adverse event was dose-dependent photosensitivity, observed in 12 (26%) of 46 patients treated with high-dose RBT-1 and in six (13%) of 45 patients treated with low-dose RBT-1 (safety population). Interpretation: RBT-1 demonstrated a statistically significant cytoprotective preconditioning response and a manageable safety profile. Further research is needed. A phase 3 trial is planned. Funding: Renibus Therapeutics, Inc.

Topical Versus Intravenous Tranexamic Acid in Patients Undergoing Cardiac Surgery: The DEPOSITION Randomized Controlled Trial.

BACKGROUND: Although intravenous tranexamic acid is used in cardiac surgery to reduce bleeding and transfusion, topical tranexamic acid results in lower plasma concentrations compared to intravenous tranexamic acid, which may lower the risk of seizures. We aimed to determine whether topical tranexamic acid reduces the risk of in-hospital seizure without increasing the risk of transfusion among cardiac surgery patients. METHODS: We conducted a multicenter, double dummy, blinded, randomized controlled trial of patients recruited by convenience sampling in academic hospitals undergoing cardiac surgery with cardiopulmonary bypass. Between September 17, 2019, and November 28, 2023, a total of 3242 patients from 16 hospitals in 6 countries were randomly assigned (1:1 ratio) to receive either intravenous tranexamic acid (control) through surgery or topical tranexamic acid (treatment) at the end of surgery. The primary outcome was seizure, and the secondary outcome was red blood cell transfusion. After the last planned interim analysis-when 75% of anticipated participants had completed follow up-the Data and Safety Monitoring Board recommended to terminate the trial, and upon unblinding, the Operations Committee stopped the trial for safety. RESULTS: Among 3242 randomized patients (mean age, 66.0 years; 77.7% male), in-hospital seizure occurred in 4 of 1624 patients (0.2%) in the topical group and in 11 of 1628 patients (0.7%) in the intravenous group (absolute risk difference, -0.5%; 95% CI, -0.9 to 0.03; P = .07). Red blood cell transfusion occurred in 570 patients (35.1%) in the topical group and in 433 (26.8%) in the intravenous group (absolute risk difference, 8.3%; 95% CI, 5.2 to 11.5; P = .007). The absolute risk difference in transfusion of ≥4 units of red blood cells in the topical group compared to the intravenous group was 8.2% (95% CI, 3.4 to 12.9). CONCLUSIONS: Among patients having cardiac surgery, topical administration of tranexamic acid resulted in an 8.3% absolute increase in transfusion without reducing the incidence of seizure, compared to intravenous tranexamic acid.

Case series of retinal vein occlusions showing early recovery using oral l-methylfolate.

This case series describes the aggregate rate of recovery in five consecutive subjects (six eyes) with retinal vein occlusion (RVO) who received l-methylfolate and other vitamins via Ocufolin®, a medical food. Subjects were followed for 10-33 months by a single ophthalmologist. Ocufolin® was prescribed at the time of diagnosis and subjects remained on the regimen throughout the time of observation. Examinations were performed in an un-masked fashion at 3-month intervals with recording of best corrected visual acuity (BCVA), average retinal nerve fiber layer (ARNFL) and central macular thickness (CMT), and fundus (examination of the retina, macula, optic nerve, and vessels) photography. Testing was done for vitamin deficiencies, vascular and coagulable risk factors, and methylenetetrahydrofolate reductase (MTHFR) polymorphisms. Vitamin deficiencies and vascular risk factors were found in all subjects, and all four tested subjects carried at least one MTHFR polymorphism. By the end of the study period BCVA in all subjects was 20/25 or better. Cystoid macular edema was identified and measured by optical coherence tomography (OCT). The percent change was calculated and plotted at 3-month intervals using the percent change in thickness from the time of diagnosis and percent change toward normative values for ARNFL and CMT. The total reduction in thickness of ARNFL and CMT from time of diagnosis was 44.19% and 30.27%, respectively. The comparison to normative data shows a reduction of ARNFL from 164.2% to 94% and CMT from 154.4% to 112.7% of normal thickness (100%). Plots showed the aggregate recovery was most rapid over the first 3 months and slowed over the next 3 months with most of the recovery taking place within 6 months of treatment. The rate of improvement in BCVA and resolution of retinal thickening was found to be better than predicted on historical grounds. No subjects progressed from nonischemic to ischemic RVO. Vitamin deficiencies, vascular risk factors, and genetic predisposition to oxidative stress were common in this RVO series. It appears that addressing these factors with Ocufolin® had a salutary effect on recovery.

Small-pore hydridic frameworks store densely packed hydrogen.

Nanoporous materials have attracted great attention for gas storage, but achieving high volumetric storage capacity remains a challenge. Here, by using neutron powder diffraction, volumetric gas adsorption, inelastic neutron scattering and first-principles calculations, we investigate a magnesium borohydride framework that has small pores and a partially negatively charged non-flat interior for hydrogen and nitrogen uptake. Hydrogen and nitrogen occupy distinctly different adsorption sites in the pores, with very different limiting capacities of 2.33 H2 and 0.66 N2 per Mg(BH4)2. Molecular hydrogen is packed extremely densely, with about twice the density of liquid hydrogen (144 g H2 per litre of pore volume). We found a penta-dihydrogen cluster where H2 molecules in one position have rotational freedom, whereas H2 molecules in another position have a well-defined orientation and a directional interaction with the framework. This study reveals that densely packed hydrogen can be stabilized in small-pore materials at ambient pressures.

Prioritizing water availability study settings to address geogenic contaminants and related societal factors.

Water availability for human and ecological uses depends on both water quantity and water quality. The U.S. Geological Survey (USGS) is developing strategies for prioritizing regional-scale and watershed basin-scale studies of water availability across the nation. Previous USGS ranking processes for basin-scale studies incorporated primarily water quantity factors but are now considering additional water quality factors. This study presents a ranking based on the potential impacts of geogenic constituents on water quality and consideration of societal factors related to water quality. High-concentration geogenic constituents, including trace elements and radionuclides, are among the most prevalent contaminants limiting water availability in the USA and globally. Geogenic constituents commonly occur in groundwater because of subsurface water-rock interactions, and their distributions are controlled by complex geochemical processes. Geogenic constituent mobility can also be affected by human activities (e.g., mining, energy production, irrigation, and pumping). Societal factors and relations to drinking water sources and water quality information are often overlooked when evaluating research priorities. Sociodemographic characteristics, data gaps resulting from historical data-collection disparities, and infrastructure condition/age are examples of factors to consider regarding environmental justice. This paper presents approaches for ranking and prioritizing potential basin-scale study areas across the contiguous USA by considering a suite of conventional physical and geochemical variables related to geogenic constituents, with and without considering variables related to societal factors. Simultaneous consideration of societal and conventional factors could provide decision makers with more diverse, interdisciplinary tools to increase equity and reduce bias in prioritizing focused research areas and future water availability studies.

Evaluating the effects of simulation training on stroke thrombolysis: a systematic review and meta-analysis.

BACKGROUND: Ischaemic strokes are medical emergencies, and reperfusion treatment, most commonly intravenous thrombolysis, is time-critical. Thrombolysis administration relies on well-organised pathways of care with highly skilled and efficient clinicians. Simulation training is a widespread teaching modality, but results from studies on the impact of this intervention have yet to be synthesised. This systematic review and meta-analysis aimed to synthesise the evidence and provide a recommendation regarding the effects of simulation training for healthcare professionals on door-to-needle time in the emergency thrombolysis of patients with ischaemic stroke. METHODS: Seven electronic databases were systematically searched (last updated 12th July 2023) for eligible full-text articles and conference abstracts. Results were screened for relevance by two independent reviewers. The primary outcome was door-to-needle time for recombinant tissue plasminogen activator administration in emergency patients with ischaemic stroke. The secondary outcomes were learner-centred, improvements in knowledge and communication, self-perceived usefulness of training, and feeling 'safe' in thrombolysis-related decision-making. Data were extracted, risk of study bias assessed, and analysis was performed using RevMan™ software (Web version 5.6.0, The Cochrane Collaboration). The quality of the evidence was assessed using the Medical Education Research Study Quality Instrument. RESULTS: Eleven studies were included in the meta-analysis and nineteen in the qualitative synthesis (n = 20,189 total patients). There were statistically significant effects of simulation training in reducing door-to-needle time; mean difference of 15 min [95% confidence intervals (CI) 8 to 21 min]; in improving healthcare professionals' acute stroke care knowledge; risk ratio (RR) 0.42 (95% CI 0.30 to 0.60); and in feeling 'safe' in thrombolysis-related decision-making; RR 0.46 (95% CI 0.36 to 0.59). Furthermore, simulation training improved healthcare professionals' communication and was self-perceived as useful training. CONCLUSION: This meta-analysis showed that simulation training improves door-to-needle times for the delivery of thrombolysis in ischaemic stroke. However, results should be interpreted with caution due to the heterogeneity of the included studies.

Estimating Lithium Concentrations in Groundwater Used as Drinking Water for the Conterminous United States.

Lithium (Li) concentrations in drinking-water supplies are not regulated in the United States; however, Li is included in the 2022 U.S. Environmental Protection Agency list of unregulated contaminants for monitoring by public water systems. Li is used pharmaceutically to treat bipolar disorder, and studies have linked its occurrence in drinking water to human-health outcomes. An extreme gradient boosting model was developed to estimate geogenic Li in drinking-water supply wells throughout the conterminous United States. The model was trained using Li measurements from ∼13,500 wells and predictor variables related to its natural occurrence in groundwater. The model predicts the probability of Li in four concentration classifications, ≤4 µg/L, >4 to ≤10 µg/L, >10 to ≤30 µg/L, and >30 µg/L. Model predictions were evaluated using wells held out from model training and with new data and have an accuracy of 47-65%. Important predictor variables include average annual precipitation, well depth, and soil geochemistry. Model predictions were mapped at a spatial resolution of 1 km2 and represent well depths associated with public- and private-supply wells. This model was developed by hydrologists and public-health researchers to estimate Li exposure from drinking water and compare to national-scale human-health data for a better understanding of dose-response to low (<30 µg/L) concentrations of Li.

Disembodied, dehumanised but safe and feasible: The social-spatial flow of a pandemic OSCE.

INTRODUCTION: The Objective Structured Clinical Examination (OSCE) is a key feature of healthcare education assessment. Many aspects of the OSCE are well-investigated, but not so its sociomaterial assemblage. The Covid-19 pandemic provided a unique opportunity to (re)consider taken-for-granted OSCE practices. Drawing on Law's modes of ordering, our aim was to demonstrate the 'mangle of practice' between space and people; the spatialised and spatialising processes of an OSCE. METHODS: We used a case study approach to critically examine a redesigned final year MBChB OSCE held during the pandemic. We used multiple sources of data to attune to human and non-human actors: OSCE documentation, photographs, field notes and semi-structured interviews with OSCE staff/organisers. Law's modes of ordering was used as an analytical lens to critically consider how people and things flowed through the adapted OSCE. FINDINGS: The overarching ordering was the delivery of a 'pandemic safe' OSCE. This necessitated reordering of 'usual' process to deliver a socially distanced, safe flow of human and non-human actors through the assessment space. Each change had material and social 'knock on' effects. We identified three main interrelated orderings: Substituting technologies for bodies: Disembodied and dehumanised but feasible; Flow through space: Architectural affordances and one-way traffic; Barriers to flow: Time and technology. DISCUSSION: Looking at the OSCE through a sociomaterial lens allows us to critically examine the OSCE's essential and complex processes and the restrictions and affordances of the spaces and props within the OSCE. In doing so, we open the possibility of considering alternative ways of doing OSCEs in the future. Moreover, conceptualising the OSCE as a living set of socially (human) and materially (nonhuman) enacted processes changes the social perception of the OSCE and highlights that an OSCE has agency on people, places and things.

The reliability of posterior malleolar ankle fracture assessment: a unique perspective.

AIM: This study aims to elucidate the pathology of PMFs in the South African population, establish correlations between fracture patterns and international classification guidelines and evaluate the interobserver reliability of current classifications. METHODS: A retrospective review was conducted in a multicentre analysis over a one-year period from January 2019 to December 2019 at our institution. Computer tomography scans for foot and ankle injuries were reviewed, and posterior malleolus fractures were included. Pathoanatomical data was collected and analysed according to known classification systems and subsequent treatment modalities evaluated. A panel of observers individually reviewed radiographic data to determine interobserver reliability. RESULTS: A total of 71 patients were included with a mean age of 41 ± 13.4 years (range 18-78) and a female predominant population (69%). A greater proportion of injuries were high energy (23.9%), with significant fragment comminution (53.5%), and half (52.1%) of all injuries were subluxated/dislocated at presentation. A total of 93% of injuries were managed operatively, despite theatre access limitations resulting in significant delays to fixation (19.1 days). Despite good pathoanatomical agreement with most international classifications, interobserver reliability was poor (Krippendorff α-coefficient < 0.667). Inconsistent treatment patterns in operative and non-operative strategies are reported. CONCLUSION: A unique patient population of younger, female individuals incurred posterior malleolar fractures due to higher energy mechanisms of injury. Whilst injury patterns were mostly comparable, significant interobserver variability was noted. Resource limitations, diagnostic challenges, poorly defined and inconsistent treatment strategies, inevitably impact outcomes within the South African population. LEVEL OF EVIDENCE: Level III.

Mortality and Severe Complications Among Newly Graduated Surgeons in the United States.

OBJECTIVE: To evaluate severe complications and mortality over years of independent practice among general surgeons. BACKGROUND: Despite concerns that newly graduated general surgeons may be unprepared for independent practice, it is unclear whether patient outcomes differ between early and later career surgeons. METHODS: We used Medicare claims for patients discharged between July 1, 2007 and December 31, 2019 to evaluate 30-day severe complications and mortality for 26 operations defined as core procedures by the American Board of Surgery. Generalized additive mixed models were used to assess the association between surgeon years in practice and 30-day outcomes while adjusting for differences in patient, hospital, and surgeon characteristics. RESULTS: The cohort included 1,329,358 operations performed by 14,399 surgeons. In generalized mixed models, the relative risk (RR) of mortality was higher among surgeons in their first year of practice compared with surgeons in their 15th year of practice [5.5% (95% CI: 4.1%-7.3%) vs 4.7% (95% CI: 3.5%-6.3%), RR: 1.17 (95% CI: 1.11-1.22)]. Similarly, the RR of severe complications was higher among surgeons in their first year of practice compared with surgeons in their 15th year of practice [7.5% (95% CI: 6.6%-8.5%) versus 6.9% (95% CI: 6.1%-7.9%), RR: 1.08 (95% CI: 1.03-1.14)]. When stratified by individual operation, 21 operations had a significantly higher RR of mortality and all 26 operations had a significantly higher RR of severe complications in the first compared with the 15th year of practice. CONCLUSIONS: Among general surgeons performing common operations, rates of mortality and severe complications were higher among newly graduated surgeons compared with later career surgeons.

Linking vertical movements of large pelagic predators with distribution patterns of biomass in the open ocean.

Many predator species make regular excursions from near-surface waters to the twilight (200 to 1,000 m) and midnight (1,000 to 3,000 m) zones of the deep pelagic ocean. While the occurrence of significant vertical movements into the deep ocean has evolved independently across taxonomic groups, the functional role(s) and ecological significance of these movements remain poorly understood. Here, we integrate results from satellite tagging efforts with model predictions of deep prey layers in the North Atlantic Ocean to determine whether prey distributions are correlated with vertical habitat use across 12 species of predators. Using 3D movement data for 344 individuals who traversed nearly 1.5 million km of pelagic ocean in [Formula: see text]42,000 d, we found that nearly every tagged predator frequented the twilight zone and many made regular trips to the midnight zone. Using a predictive model, we found clear alignment of predator depth use with the expected location of deep pelagic prey for at least half of the predator species. We compared high-resolution predator data with shipboard acoustics and selected representative matches that highlight the opportunities and challenges in the analysis and synthesis of these data. While not all observed behavior was consistent with estimated prey availability at depth, our results suggest that deep pelagic biomass likely has high ecological value for a suite of commercially important predators in the open ocean. Careful consideration of the disruption to ecosystem services provided by pelagic food webs is needed before the potential costs and benefits of proceeding with extractive activities in the deep ocean can be evaluated.

Multispectral multibeam backscatter response of heterogeneous rhodolith beds.

Acoustic backscatter has been used as a tool to map the seafloor in greater detail and plays an increasingly important role in seafloor mapping to meet multiple ocean management needs. An outstanding challenge to the use of backscatter for seafloor mapping is the distinction between acoustically similar substrates, such as mixed sediments from rhodoliths. Rhodolith beds are a biogenic substrate that provides important ecological services, and are typically classified as a single categorical substrate type-though nodules coverage may be spatially variable. Recently, multispectral acoustic backscatter has demonstrated great potential to improve thematic seafloor mapping compared to single-frequency systems. This work employs multispectral multibeam backscatter and underwater imagery to characterize and map rhodolith beds in the Costa das Algas Marine Protected Area (Brazil). A support vector machine classifier was used to classify multifrequency backscatter mosaics according to rhodolith classes identified from underwater imagery. Results suggest that multispectral backscatter is effective both in providing information for mapping different proportions of rhodolith coverage and in predicting the presence or absence of these nodules. The backscatter of the lowest frequency was the most useful for distinguishing variable proportions of rhodolith coverage, and the two higher frequencies were better predictors of presence and absence.

Evaluating Educational Outcomes Using Patient Outcomes of New Surgeons Performing Partial Colectomy Compared to Cholecystectomy.

PURPOSE: Despite ongoing efforts to improve surgical education, surgical residents face gaps in their training. However, it is unknown if differences in the training of surgeons are reflected in the patient outcomes of those surgeons once they enter practice. This study aimed to compare the patient outcomes among new surgeons performing partial colectomy-a common procedure for which training is limited-and cholecystectomy-a common procedure for which training is robust. METHOD: The authors retrospectively analyzed all adult Medicare claims data for patients undergoing inpatient partial colectomy and inpatient cholecystectomy between 2007 and 2018. Generalized additive mixed models were used to investigate the associations between surgeon years in practice and risk-adjusted rates of 30-day serious complications and death for patients undergoing partial colectomy and cholecystectomy. RESULTS: A total of 14,449 surgeons at 4,011 hospitals performed 340,114 partial colectomy and 355,923 cholecystectomy inpatient operations during the study period. Patients undergoing a partial colectomy by a surgeon in their 1st vs 15th year of practice had higher rates of serious complications (5.22% [95% CI, 4.85%-5.60%] vs 4.37% [95% CI, 4.22%-4.52%]; P < .01) and death (3.05% [95% CI, 2.92%-3.17%] vs 2.83% [95% CI, 2.75%-2.91%]; P < .01). Patients undergoing a cholecystectomy by a surgeon in their 1st vs 15th year of practice had similar rates of 30-day serious complications (4.11% vs 3.89%; P = .11) and death (1.71% vs 1.70%; P = .93). CONCLUSIONS: Patients undergoing partial colectomy faced a higher risk of serious complications and death when the operation was performed by a new surgeon compared to an experienced surgeon. Conversely, patient outcomes following cholecystectomy were similar for new and experienced surgeons. More attention to partial colectomy during residency training may benefit patients.

Homocysteine Reduction for Stroke Prevention: Regarding the Recent AHA/ASA 2021 Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack.

Reduction of secondary ischemic stroke risk following an initial stroke is an important goal. The 2021 Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack assembles opportunities for up to 80% secondary stroke reduction. Homocysteine reduction was not included in the recommendations. The reduction of homocysteine with low doses of folic acid has been shown to reduce ischemic stroke and all stroke. This has been obscured by studies using high doses of folic acid and cyanocobalamin in patients with renal failure and Methylenetetrahydrofolate reductase (MTHFR) polymorphisms. The confounding impacts of high dose folic acid and cyanocobalamin toxicity in renal failure and MTHFR C677T subgroups are discussed. New studies show that their toxicity is due to non-bioequivalence to the natural dietary forms, L-methylfolate and methylcobalamin. Low doses of folic acid and cyanocobalamin are safer than high doses for these subpopulations. Even lower toxicity with greater effectiveness for reducing homocysteine is seen with L-methylfolate and methylcobalamin, which are safe at high doses. Retinal vascular imaging is a noninvasive method for evaluating central nervous system (CNS) microangiopathy. A formulation containing l-methylfolate and methylcobalamin has been shown to reduce homocysteine and increase perfusion in diabetic retinopathy. This supports homocysteine intervention for CNS ischemia. Future ischemic stroke intervention studies could benefit from monitoring retinal perfusion to estimate the impact of risk reduction strategies. The omission of a recommendation for homocysteine and secondary stroke reduction through the use of B vitamins should be reconsidered in light of re-analysis of major B vitamin intervention studies and new technologies for monitoring CNS perfusion. We recommend revision of the 2021 Guideline to include homocysteine reduction with low doses of folic acid and cyanocobalamin, or better yet, L-methylfolate and methylcobalamin, making a good clinical guideline better.

Hydrogen Storage with Aluminum Formate, ALF: Experimental, Computational, and Technoeconomic Studies.

Long-duration storage of hydrogen is necessary for coupling renewable H2 with stationary fuel cell power applications. In this work, aluminum formate (ALF), which adopts the ReO3-type structure, is shown to have remarkable H2 storage performance at non-cryogenic (>120 K) temperatures and low pressures. The most promising performance of ALF is found between 120 K and 160 K and at 10 bar to 20 bar. The study illustrates H2 adsorption performance of ALF over the 77 K to 296 K temperature range using gas isotherms, in situ neutron powder diffraction, and DFT calculations, as well as technoeconomic analysis (TEA), illustrating ALF's competitive performance for long-duration storage versus compressed hydrogen and leading metal-organic frameworks. In the TEA, it is shown that ALF's storage capacity, when combined with a temperature/pressure swing process, has advantages versus compressed H2 at a fraction of the pressure (15 bar versus 350 bar). Given ALF's performance in the 10 bar to 20 bar regime under moderate cooling, it is particularly promising for use in safe storage systems serving fuel cells.

Adaptive Pore Opening to Form Tailored Adsorption Sites in a Cooperatively Flexible Framework Enables Record Inverse Propane/Propylene Separation.

A proposed low-energy alternative to the separation of alkanes from alkenes by energy-intensive cryogenic distillation is separation by porous adsorbents. Unfortunately, most adsorbents preferentially take up the desired, high-value major component alkene, requiring frequent regeneration. Adsorbents with inverse selectivity for the minor component alkane would enable the direct production of purified, reagent-grade alkene, greatly reducing global energy consumption. However, such materials are exceedingly rare, especially for propane/propylene separation. Here, we report that through adaptive and spontaneous pore size and shape adaptation to optimize an ensemble of weak noncovalent interactions, the structurally responsive metal-organic framework CdIF-13 (sod-Cd(benzimidazolate)2) exhibits inverse selectivity for propane over propylene with record-setting separation performance under industrially relevant temperature, pressure, and mixture conditions. Powder synchrotron X-ray diffraction measurements combined with first-principles calculations yield atomic-scale insight and reveal the induced fit mechanism of adsorbate-specific pore adaptation and ensemble interactions between ligands and adsorbates. Dynamic column breakthrough measurements confirm that CdIF-13 displays selectivity under mixed-component conditions of varying ratios, with a record measured selectivity factor of α ≈ 3 at 95:5 propylene:propane at 298 K and 1 bar. When sequenced with a low-cost rigid adsorbent, we demonstrated the direct purification of propylene under ambient conditions. This combined atomic-level structural characterization and performance testing firmly establishes how cooperatively flexible materials can be capable of unprecedented separation factors.

Optical opening of the blood-brain barrier for targeted and ultra-sparse viral infection of cells in mouse cortex.

Adeno-associated viruses (AAVs) are used in a wide array of experimental situations for driving expression of biosensors, recombinases, and opto-/chemo-genetic actuators in the brain. However, conventional approaches for minimally invasive, spatially precise, and ultra-sparse AAV-mediated transduction of cells during imaging experiments have remained a significant challenge. Here, we show that intravenous injection of commercially available AAVs at different doses, combined with laser-based perforation of cortical capillaries through a cranial widow, allows for ultra-sparse, titratable, and micron-level precision for delivery of viral vectors with relatively little inflammation or tissue damage. Further, we show the utility of this approach for eliciting sparse expression of GCaMP6, channelrhodopsin, or fluorescent reporters in neurons and astrocytes within specific functional domains in normal and stroke-damaged cortex. This technique represents a facile approach for targeted delivery of viral vectors that should assist in the study of cell types and circuits in the cortex.

Prescribed Opioid Dosages, Payer Type, and Self-Reported Outcomes After Surgical Procedures in Michigan, 2018-2020.

Importance: Collaborative quality improvement (CQI) models, often supported by private payers, create hospital networks to improve health care delivery. Recently, these systems have focused on opioid stewardship; however, it is unclear whether reduction in postoperative opioid prescribing occurs uniformly across health insurance payer types. Objective: To evaluate the association between insurance payer type, postoperative opioid prescription size, and patient-reported outcomes in a large statewide CQI model. Design, Setting, and Participants: This retrospective cohort study used data from 70 hospitals within the Michigan Surgical Quality Collaborative clinical registry for adult patients (age ≥18 years) undergoing general, colorectal, vascular, or gynecologic surgical procedures between January 1, 2018, and December 31, 2020. Exposure: Insurance type, classified as private, Medicare, or Medicaid. Main Outcomes and Measures: The primary outcome was postoperative opioid prescription size in milligrams of oral morphine equivalents (OME). Secondary outcomes were patient-reported opioid consumption, refill rate, satisfaction, pain, quality of life, and regret about undergoing surgery. Results: A total of 40 149 patients (22 921 [57.1%] female; mean [SD] age, 53 [17] years) underwent surgery during the study period. Within this cohort, 23 097 patients (57.5%) had private insurance, 10 667 (26.6%) had Medicare, and 6385 (15.9%) had Medicaid. Unadjusted opioid prescription size decreased for all 3 groups during the study period from 115 to 61 OME for private insurance patients, from 96 to 53 OME for Medicare patients, and from 132 to 65 OME for Medicaid patients. A total of 22 665 patients received a postoperative opioid prescription and had follow-up data for opioid consumption and refill. The rate of opioid consumption was highest among Medicaid patients throughout the study period (16.82 OME [95% CI, 12.57-21.07 OME] greater than among patients with private insurance) but increased the least over time. The odds of refill significantly decreased over time for patients with Medicaid compared with patients with private insurance (odds ratio, 0.93; 95% CI, 0.89-0.98). Adjusted refill rates for private insurance remained between 3.0% and 3.1% over the study period; adjusted refill rates among Medicare and Medicaid patients decreased from 4.7% to 3.1% and 6.5% to 3.4%, respectively, by the end of the study period. Conclusions and Relevance: In this retrospective cohort study of surgical patients in Michigan from 2018 to 2020, postoperative opioid prescription size decreased across all payer types, and differences between groups narrowed over time. Although funded by private payers, the CQI model appeared to have benefitted patients with Medicare and Medicaid as well.