Texas Senate Bill 8 significantly reduced travel to abortion clinics in Texas.

The Dobbs v. Jackson decision by the United States Supreme Court has rescinded the constitutional guarantee of abortion across the United States. As a result, at least 13 states have banned abortion access with unknown effects. Using "Texas" SB8 law that similarly restricted abortions in Texas, we provide insight into how individuals respond to these restrictions using aggregated and anonymized human mobility data. We find that "Texas" SB 8 law reduced mobility near abortion clinics in Texas by people who live in Texas and those who live outside the state. We also find that mobility from Texas to abortion clinics in other states increased, with notable increases in Missouri and Arkansas, two states that subsequently enacted post-Dobbs bans. These results highlight the importance of out-of-state abortion services for women living in highly restrictive states.

College openings in the United States increase mobility and COVID-19 incidence.

School and college reopening-closure policies are considered one of the most promising non-pharmaceutical interventions for mitigating infectious diseases. Nonetheless, the effectiveness of these policies is still debated, largely due to the lack of empirical evidence on behavior during implementation. We examined U.S. college reopenings' association with changes in human mobility within campuses and in COVID-19 incidence in the counties of the campuses over a twenty-week period around college reopenings in the Fall of 2020. We used an integrative framework, with a difference-in-differences design comparing areas with a college campus, before and after reopening, to areas without a campus and a Bayesian approach to estimate the daily reproductive number (Rt). We found that college reopenings were associated with increased campus mobility, and increased COVID-19 incidence by 4.9 cases per 100,000 (95% confidence interval [CI]: 2.9-6.9), or a 37% increase relative to the pre-period mean. This reflected our estimate of increased transmission locally after reopening. A greater increase in county COVID-19 incidence resulted from campuses that drew students from counties with high COVID-19 incidence in the weeks before reopening (χ2(2) = 8.9, p = 0.012) and those with a greater share of college students, relative to population (χ2(2) = 98.83, p < 0.001). Even by Fall of 2022, large shares of populations remained unvaccinated, increasing the relevance of understanding non-pharmaceutical decisions over an extended period of a pandemic. Our study sheds light on movement and social mixing patterns during the closure-reopening of colleges during a public health threat, and offers strategic instruments for benefit-cost analyses of school reopening/closure policies.

A new conceptual framework for the transformation of groundwater dissolved organic matter.

Groundwater comprises 95% of the liquid fresh water on Earth and contains a diverse mix of dissolved organic matter (DOM) molecules which play a significant role in the global carbon cycle. Currently, the storage times and degradation pathways of groundwater DOM are unclear, preventing an accurate estimate of groundwater carbon sources and sinks for global carbon budgets. Here we reveal the transformations of DOM in aging groundwater using ultra-high resolution mass spectrometry combined with radiocarbon dating. Long-term anoxia and a lack of photodegradation leads to the removal of oxidised DOM and a build-up of both reduced photodegradable formulae and aerobically biolabile formulae with a strong microbial signal. This contrasts with the degradation pathway of DOM in oxic marine, river, and lake systems. Our findings suggest that processes such as groundwater extraction and subterranean groundwater discharge to oceans could result in up to 13 Tg of highly photolabile and aerobically biolabile groundwater dissolved organic carbon released to surface environments per year, where it can be rapidly degraded. These findings highlight the importance of considering groundwater DOM in global carbon budgets.

Association of opioid utilization management with prescribing and overdose.

OBJECTIVES: Deaths from prescription opioids have reached epidemic levels in the United States, yet little is known about how insurers' coverage policies may affect rates of fatal and nonfatal overdose among individuals filling an opioid prescription. STUDY DESIGN: Retrospective cohort study using 2010-2016 Medicare claims data for beneficiaries with 1 or more filled prescriptions for a Schedule II opioid. METHODS: Outcomes were opioid volume dispensed in morphine milligram equivalents (MME), number of days supplied, and number of pills dispensed on each prescription and emergency department or inpatient stay associated with an opioid overdose during a prescription or within 7 days of the end of the prescription. RESULTS: A total of 7.03 million prescriptions for Schedule II opioids were dispensed over 1.87 million Part D beneficiary-years. The 7.03 million opioid prescriptions were associated with 8.5 opioid overdoses per 10,000 prescriptions. Prior authorization was associated with larger opioid volumes per prescription (103.6 MME; 95% CI, 36.2-171.0). Step therapy was associated with a greater number of days supplied (0.62 days; 95% CI, 0.10-1.13) and more pills dispensed (6.12 pills; 95% CI, 2.17-10.1). Quantity limits were associated with smaller opioid volumes (24.3 MME; 95% CI, 12.3-36.3) and fewer pills dispensed (2.35 pills; 95% CI, 1.77-2.93). In adjusted models, beneficiaries filling an opioid requiring prior authorization experienced 3.3 fewer overdoses per 10,000 prescriptions (95% CI, 0.41-6.2). CONCLUSIONS: Opioid utilization management among these beneficiaries was associated with mixed effects on opioid prescribing, and prior authorization was associated with a decreased likelihood of subsequent overdose. Further work exploring the impact of utilization management and insurer policies is needed.

A prospective examination of health care costs associated with posttraumatic stress disorder diagnostic status and symptom severity among veterans.

Posttraumatic stress disorder (PTSD) is associated with increased health care costs; however, most studies exploring this association use PTSD diagnostic data in administrative records, which can contain inaccurate diagnostic information and be confounded by the quantity of service use. We used a diagnostic interview to determine PTSD diagnostic status and examined associations between PTSD symptom severity and health care costs and utilization, extracted from Veteran Health Administration (VHA) administrative databases. Using a nationwide longitudinal sample of U.S. veterans with and without PTSD (N = 1,377) enrolled in VHA health care, we determined the costs and utilization of mental health and non-mental health outpatient, pharmacy, and inpatient services for 1 year following cohort enrollment. Relative to veterans without PTSD, those with PTSD had higher total health care, B = 0.47; mental health clinic care, B = 0.72; non-mental health clinic care, B = 0.30; and pharmacy costs, B = 0.72, ps < .001. More severe PTSD symptoms were associated with mental health clinic care costs, B = 0.12; non-mental health clinic care costs, B = 0.27; and higher odds of inpatient, B = 0.63, and emergency service use, B = 0.39, p < .001-p = .012. These findings indicate that veterans' PTSD status, determined by a clinician-administered semistructured diagnostic interview, was associated with higher health care costs and increased use of mental health and non-mental health clinic services. The findings also suggest that more severe PTSD is associated with increased costs and utilization, including costly emergency and inpatient utilization.

Impacts of state COVID-19 reopening policy on human mobility and mixing behavior.

This study quantifies the effect of the 2020 state COVID economic activity reopening policies on daily mobility and mixing behavior, adding to the economic literature on individual responses to public health policy that addresses public contagion risks. We harness cellular device signal data and the timing of reopening plans to provide an assessment of the extent to which human mobility and physical proximity in the United States respond to the reversal of state closure policies. We observe substantial increases in mixing activities, 13.56% at 4 days and 48.65% at 4 weeks, following reopening events. Echoing a theme from the literature on the 2020 closures, mobility outside the home increased on average prior to these state actions. Furthermore, the largest increases in mobility occurred in states that were early adopters of closure measures and hard-hit by the pandemic, suggesting that psychological fatigue is an important barrier to implementation of closure policies extending for prolonged periods of time.

Quantifying groundwater carbon dioxide and methane fluxes to an urban freshwater lake using radon measurements.

Freshwater lakes can play a significant role in greenhouse gas budgets as they can be sources or sinks of carbon to the atmosphere. However, there is limited information on groundwater discharge being a source of carbon to freshwater lakes. Here, we measure CO2 and CH4 in the largest urban freshwater lake in the metropolitan area of Sydney (Australia) and quantify groundwater discharge rates into the lake using radon (222Rn, a natural groundwater tracer). We also assess the spatial variability of radon, CO2 and CH4 in the lake, in addition to surface water and groundwater nutrient and carbon concentrations. Results revealed that the lake system was a source of CO2 and CH4 to the atmosphere with fluxes of 113 ± 81 and 0.3 ± 0.1 mmol/m2/d, respectively. These calculated CO2 fluxes were larger than commonly observed lake fluxes and the global average flux from lakes. However, CH4 fluxes were lower than the average global value. Based on the radon mass balance model, groundwater discharge to the lake was 16 ± 10 cm/d, which resulted in groundwater-derived CO2 and CH4 fluxes contributing 25 and 13% to the overall greenhouse gas emissions from the lake, respectively. Radon, CO2 and CH4 maps showed similar spatial distribution trends in the lake and a strong relationship between radon, NO3 and NH4 suggested groundwater flow was also a driver of nitrogen into the lake from the western side of the lake, following the general regional groundwater flow. This work provides insights into groundwater and greenhouse gas dynamics in Sydney's largest urban freshwater lake with two implications for carbon budgets: to incorporate urban lakes in global carbon budgets and to account for, the often ignored, groundwater discharge as a source of carbon to lakes.

Regularization by denoising sub-sampled Newton method for spectral CT multi-material decomposition.

Spectral Computed Tomography (CT) is an emerging technology that enables us to estimate the concentration of basis materials within a scanned object by exploiting different photon energy spectra. In this work, we aim at efficiently solving a model-based maximum-a-posterior problem to reconstruct multi-materials images with application to spectral CT. In particular, we propose to solve a regularized optimization problem based on a plug-in image-denoising function using a randomized second order method. By approximating the Newton step using a sketching of the Hessian of the likelihood function, it is possible to reduce the complexity while retaining the complex prior structure given by the data-driven regularizer. We exploit a non-uniform block sub-sampling of the Hessian with inexact but efficient conjugate gradient updates that require only Jacobian-vector products for denoising term. Finally, we show numerical and experimental results for spectral CT materials decomposition. This article is part of the theme issue 'Synergistic tomographic image reconstruction: part 1'.

The Validation and Further Development of the Multidimensional Cognitive Load Scale for Physical and Online Lectures (MCLS-POL).

Cognitive load theory (CLT) has been widely used to help understand the process of learning and to design teaching interventions. The Cognitive Load Scale (CLS) developed by Leppink and colleagues has emerged as one of the most validated and widely used self-report measures of intrinsic load (IL), extraneous load (EL), and germane load (GL). In this paper we investigated an expansion of the CLS by using a multidimensional conceptualization of the EL construct that is relevant for physical and online teaching environments. The Multidimensional Cognitive Load Scale for Physical and Online Lectures (MCLS-POL) goes beyond the CLS's operationalization of EL by expanding the EL component which originally included factors related to instructions/explanations with sub-dimensions including EL stemming from noises, and EL stemming from both media and devices within the environment. Through three studies, we investigated the reliability, and internal and external validity of the MCLS-POL using the Partial Credit Model, Confirmatory Factor Analysis, and differences between students either attending a lecture physically or online (Study 2 and 3). The results of Study 1 (N = 250) provide initial evidence for the validity and reliability of the MCLS-POL within a higher education sample, but also highlighted several potential improvements which could be made to the measure. These changes were made before re-evaluating the validity and reliability of the measure in a new sample of higher education psychology students (N = 140, Study 2), and psychological testing students (N = 119, Study 3). Together the studies provide evidence for a multidimensional conceptualization cognitive load and provide evidence of the validity, reliability, and sensitivity of the MCLS-POL and provide suggestions for future research directions.

Utilization Management in the Medicare Part D Program and Prescription Drug Utilization.

Medicare Part D has significantly enhanced access to prescription drugs among Medicare beneficiaries. However, the recent rapid rise of utilization management policies in the Medicare Part D program may have adversely affected access to prescription drugs. I study the effects of expected and observed exposure to utilization management in prescription drug utilization using Medicare Part D claims data from 2009 to 2016 and an instrumental variables strategy based on the interaction of lagged health status and the set of plans available to each beneficiary. I find that the expected share of spending subject to utilization management increases the observed share, with the smallest effect for prior authorization. Increases in the expected share of drug spending subject to prior authorization increases Part D spending by $122.27 per percentage point, with almost three-quarters of this increase being paid by the Medicare program, rather than beneficiaries or plans. Comparable increases in step therapy and quantity limit exposure increase spending by $46 and decrease spending by $31, respectively. Interestingly, increased exposure to prior authorization and quantity limits increases the average price per 30-day prescription.

Characterisation of groundwater dissolved organic matter using LCOCD: Implications for water treatment.

The polarity and molecular weight of dissolved organic matter (DOM) is an important factor determining the treatability of water for domestic supply. DOM in surface water and groundwater is comprised of a mixture of carbon with varying molecular weight ranges, with its composition driven by DOM sources and processing. Here, we present the largest dataset of chromatographic DOM in surface and groundwater samples (n = 246) using liquid chromatography organic carbon detection (LCOCD). Our data represents four categories (surface water, hyporheic zone water, local groundwater, and regional groundwater) from five different sites across Australia. In all environments, high molecular weight hydrophilic DOM such as biopolymers (BP) and humic substances (HS) are present in surface waters and are processed out of groundwater as it moves from surface water and hyporheic zones into shallow local groundwater and deeper regional groundwaters. This results in a higher percentage of low molecular weight neutrals (LMWN) and hydrophobic organic carbon (HOC) in deeper regional groundwaters. Our findings indicate that the presence of sedimentary organic matter strongly influence the character of surface and groundwater DOM, resulting in groundwater with higher HS aromaticity and molecular weight, and reduced percentage of LMWNs. We also observe highly variable hydrophilic / HOC ratios in groundwater at all sites, with 9.60% and 25.64% of samples at sites containing sedimentary peat layers and non-sedimentary peat sites respectively containing only hydrophilic dissolved organic carbon (DOC). We identify average hydrophilic / HOC ratios of 4.35 ± 3.76 and 7.53 ± 5.32 at sites containing sedimentary peat layers and non-sedimentary peat sites respectively where both hydrophilic DOC and HOC are present. Overall our results suggest that fractured rock and alluvial aquifers in sedimentary organic carbon poor environments may contain DOC which is better suited to ozonation, biologically activated carbon filtration powdered activated carbon, suspended ion exchange treatment or magnetic ion exchange resin since DOC is more hydrophilic and of lower molecular weight and lower aromaticity. Aquifers located near sedimentary organic matter layers may benefit from pre-treatment by coagulation/flocculation, sedimentation and sand filtration which have high removal efficiency for high molecular weight and polar compounds.

Contractile Fronts In The Interventricular Septum: A Case For High Frame Rate Echocardiographic Imaging.

The real time high frame rate (HFR) 2-dimensional ultrasound system, T5, at Duke University is capable of imaging at up to 1000 images per second for adult cardiac imaging. A method for detecting and visualizing the mechanical contraction fronts using HFR echocardioagraphy-derived Strain Rate Image (SRI) was described in 26 patients. The Tissue Shortening Onset front durations for echocardiographic normal patients were significantly shorter than conduction disorder patients with left bundle branch block (LBBB) with intrinsic conduction and conduction disorder patients without LBBB (non-LBBB) with simulated LBBB (sLBBB). Echocardiographic normal patients had significantly higher correlation coefficients between their SRIs and spatially inverted versions of themselves compared to non-LBBB patients with intrinsic conduction and sLBBB. In conclusion, SRIs could spatially resolve contractile event fronts in patients.

Changes in global groundwater organic carbon driven by climate change and urbanization.

Climate change and urbanization can increase pressures on groundwater resources, but little is known about how groundwater quality will change. Here, we use a global synthesis (n = 9,404) to reveal the drivers of dissolved organic carbon (DOC), which is an important component of water chemistry and substrate for microorganisms that control biogeochemical reactions. Dissolved inorganic chemistry, local climate and land use explained ~ 31% of observed variability in groundwater DOC, whilst aquifer age explained an additional 16%. We identify a 19% increase in DOC associated with urban land cover. We predict major groundwater DOC increases following changes in precipitation and temperature in key areas relying on groundwater. Climate change and conversion of natural or agricultural areas to urban areas will decrease groundwater quality and increase water treatment costs, compounding existing constraints on groundwater resources.

How water isotopes (18O, 2H, 3H) within an island freshwater lens respond to changes in rainfall.

Coastal aquifers provide an important source of water globally. Understanding how groundwater responds to changes in rainfall recharge is important for sustainable development. To this end, we investigate how water isotopes (18O, 2H, 3H) and chloride (Cl) concentrations within an island freshwater lens respond under varying rainfall conditions in a region experiencing climate change. Uniquely, this study presents a three year dataset of groundwater collected seasonally between May 2013 and August 2016 from ten wells. Variation in all tracers was observed. The Cl and tritium (3H) show opposing seasonal variation in some sections of the lens, with higher Cl observed in the austral summer when less rainfall occurs and evapotranspiration is highest. The opposite occurs in the austral winter months when 3H increases from atmospheric input via rainfall recharge, and Cl is diluted. An overall decline in 3H values and enrichment in stable water isotopes over the study period was also observed. This study shows that understanding groundwater of freshwater lenses should not rely on a single sampling campaign because seasonal variability is large. The identification of a dual recharge regime, with contributions from both winter rainfall and episodic events, has important implications for understanding the future fate of the freshwater lens on Rottnest Island. The finding that episodic rainfall is a major contributor to groundwater recharge is important and can only be assessed with a multi-year isotope dataset for groundwater and rainfall.

Changes in groundwater dissolved organic matter character in a coastal sand aquifer due to rainfall recharge.

Dissolved organic matter (DOM) in groundwater is fundamentally important with respect to biogeochemical reactions, global carbon cycling, heavy metal transport, water treatability and potability. One source of DOM to groundwater is from the transport of organic matter from the vadose zone by rainfall recharge. Changes in precipitation patterns associated with natural climate variability and climate change are expected to alter the load and character of organic matter released from these areas, which ultimately impacts on groundwater quality and DOM treatability. In order to investigate potential changes in groundwater DOM character after rainfall recharge, we sampled shallow groundwater from a coastal peat-rich sand aquifer in New South Wales, Australia, during an extended period of low precipitation (average daily precipitation rate < 1.6 mm day-1 over the 8 months prior to sampling), and after two heavy precipitation events (84 mm day-1 and 98 mm day-1 respectively). We assess changes in DOM composition after correcting for dilution by a novel combination of two advanced analytical techniques: liquid chromatography organic carbon detection (LC-OCD) and negative-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). We also assess changes in water chemistry pre- and post-rainfall. Post-rainfall, we show that the dilution-corrected amount of highly aromatic DOM molecular formulae (i.e. those categorised into the groups polyphenolics and condensed aromatics) were 1.7 and 2.0 times higher respectively than in pre-rainfall samples. We attribute this to the flushing of peat-derived DOM from buried organic material into the groundwater. We also identify that periods of low precipitation can lead to low hydrophilic/HOC ratios in groundwater (median = 4.9, n = 14). Redundancy analysis (RDA) was used to compare the HOC fraction with FT-ICR MS compound groups. We show that HOC has a more aromatic character in pre-rainfall samples, and is less similar to the aromatic groups in post-rainfall samples. This suggests that the decline in water-borne hydrophobics observed post-rainfall could be associated with preferential adsorption of the hydrophobic aromatic DOM, making post-rainfall samples less treatable for potable water supply. Post-rainfall we also observe significant increases in arsenic (leading to concentrations greater than 3 times the World Health Organisation drinking water limit of 10 µg / L). Increases in coastal rainfall due to climate change may therefore alter the composition of groundwater DOM in coastal peatland areas in ways that may impact DOM bioavailability, and increase arsenic concentrations, reducing the ease of water treatment for human consumption. To the best of our knowledge, this is the first study to identify the chemical and molecular changes of shallow groundwater DOM pre-rainfall and post-rainfall in a sedimentary organic carbon rich environment through multiple analytical techniques.

Hydrological and geochemical responses of fire in a shallow cave system.

The influence of wildfire on surface soil and hydrology has been widely investigated, while its impact on the karst vadose zone is still poorly understood. A moderate to severe experimental fire was conducted on a plot (10 m × 10 m) above the shallow Wildman's Cave at Wombeyan Caves, New South Wales, Australia in May 2016. Continuous sampling of water stable isotopes, inorganic geochemistry and drip rates were conducted from Dec 2014 to May 2017. After the fire, drip discharge patterns were significantly altered, which is interpreted as the result of increased preferential flows and decreased diffuse flows in the soil. Post-fire drip water δ18O decreased by 6.3‰ in the first month relative to the average pre-fire isotopic composition. Post-fire monitoring showed an increase in drip water δ18O in the following six months. Bedrock related solutes (calcium, magnesium, strontium) decreased rapidly after the fire due to reduced limestone dissolution time and potentially reduced soil CO2. Soil- and ash-derived solutes (boron, lead, potassium, sodium, silicon, iodine and iron) all decreased after the fire due to volatilisation at high temperatures, except for SO42-. This is the first study to understand the hydrological impact from severe fires conducted on a karst system. It provides new insights on the cave recharge process, with a potential explanation for the decreased d18O in speleothem-based fire study, and also utilise the decreased bedrock solutes to assess the wildfire impacts both in short and long time scales.

Effect of Transient Wave Forcing on the Behavior of Arsenic in a Nearshore Aquifer.

Groundwater-coastal water interactions influence the fate of inorganic chemicals in nearshore aquifers and their flux to receiving coastal waters. This study evaluates the impact of variable wave conditions on the geochemical changes and distribution of mobile arsenic (As) in a nearshore aquifer. Field measurements in a sandy nearshore aquifer on Lake Erie, Canada, are presented with geochemical changes analyzed over a period of high waves. A numerical model of wave-induced groundwater flow dynamics, validated against field data, is used to provide insight into the physical flow processes underlying the observed geochemical changes. Rapid changes in dissolved As, Fe, Mn, and S demonstrate the importance of reactions as well as dynamic transport in controlling the behavior of reactive species, especially those that are redox sensitive. Field data suggest the presence of sediment traps, which under certain hydrological and geochemical conditions may result in a "hot moment" with episodic release of As. The study provides new insight into factors controlling the fate of reactive species in dynamic coastal environments as required to better predict chemical fluxes to coastal waters. Additionally, it highlights the need to pay particular attention to "hot moments" for reaction and transport caused by storms and waves.

A Convex Reconstruction Model for X-ray Tomographic Imaging with Uncertain Flat-fields.

Classical methods for X-ray computed tomography are based on the assumption that the X-ray source intensity is known, but in practice, the intensity is measured and hence uncertain. Under normal operating conditions, when the exposure time is sufficiently high, this kind of uncertainty typically has a negligible effect on the reconstruction quality. However, in time- or dose-limited applications such as dynamic CT, this uncertainty may cause severe and systematic artifacts known as ring artifacts. By carefully modeling the measurement process and by taking uncertainties into account, we derive a new convex model that leads to improved reconstructions despite poor quality measurements. We demonstrate the effectiveness of the methodology based on simulated and real data sets.

Effects of Medicare coverage for the chronically ill on health insurance, utilization, and mortality: Evidence from coverage expansions affecting people with end-stage renal disease.

I study the effect of the 1973 expansions of Medicare coverage among individuals with end-stage renal disease (ESRD) on insurance coverage, health care utilization, and mortality. I find that the expansions increased insurance coverage by between 22 and 30 percentage points, in models that include trends in age, with the increase explained by Medicare coverage, and increased physician visits by 25-35 percent. These expansions also decreased mortality due to kidney disease in the under 65 population by between 0.5 and 1.0 deaths per 100,000. Lastly, I provide evidence for two mechanisms that affected mortality: an increase in access to and use of treatment, which may be due to changes in insurance coverage; and an increase in entry of dialysis clinics and transplant programs.