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In this paper, I discuss common endogeneity problems found in entrepreneurship research. I show how entrepreneurship researchers, particularly those working with observational data, typically face several specific endogeneity threats in a given study. I then show through a series of simulated of datasets instrument variable approaches that effectively address endogeneity in a variety of research designs. I discuss best-practice recommendations for integrating instrument variables into entrepreneurship research at the study design phase, and outline potential sources for instruments.

ImportanceEvidence on the effectiveness and safety of COVID-19 therapies across a diverse population with varied risk factors is needed to inform clinical practice.ObjectiveTo assess the safety of neutralizing monoclonal antibodies (nMAbs) for the treatment of COVID-19 and their association with adverse outcomes.Design, Setting, and ParticipantsThis retrospective cohort study included 167 183 patients from a consortium of 4 health care systems based in California, Minnesota, Texas, and Utah. The study included nonhospitalized patients 12 years and older with a positive COVID-19 laboratory test collected between November 9, 2020, and January 31, 2022, who met at least 1 emergency use authorization criterion for risk of a poor outcome.ExposureFour nMAb products (bamlanivimab, bamlanivimab-etesevimab, casirivimab-imdevimab, and sotrovimab) administered in the outpatient setting.Main Outcomes and MeasuresClinical and SARS-CoV-2 genomic sequence data and propensity-adjusted marginal structural models were used to assess the association between treatment with nMAbs and 4 outcomes: all-cause emergency department (ED) visits, hospitalization, death, and a composite of hospitalization or death within 14 days and 30 days of the index date (defined as the date of the first positive COVID-19 test or the date of referral). Patient index dates were categorized into 4 variant epochs: pre-Delta (November 9, 2020, to June 30, 2021), Delta (July 1 to November 30, 2021), Delta and Omicron BA.1 (December 1 to 31, 2021), and Omicron BA.1 (January 1 to 31, 2022).ResultsAmong 167 183 patients, the mean (SD) age was 47.0 (18.5) years; 95 669 patients (57.2%) were female at birth, 139 379 (83.4%) were White, and 138 900 (83.1%) were non-Hispanic. A total of 25 241 patients received treatment with nMAbs. Treatment with nMAbs was associated with lower odds of ED visits within 14 days (odds ratio [OR], 0.76; 95% CI, 0.68-0.85), hospitalization within 14 days (OR, 0.52; 95% CI, 0.45-0.59), and death within 30 days (OR, 0.14; 95% CI, 0.10-0.20). The association between nMAbs and reduced risk of hospitalization was stronger in unvaccinated patients (14-day hospitalization: OR, 0.51; 95% CI, 0.44-0.59), and the associations with hospitalization and death were stronger in immunocompromised patients (hospitalization within 14 days: OR, 0.31 [95% CI, 0.24-0.41]; death within 30 days: OR, 0.13 [95% CI, 0.06-0.27]). The strength of associations of nMAbs increased incrementally among patients with a greater probability of poor outcomes; for example, the ORs for hospitalization within 14 days were 0.58 (95% CI, 0.48-0.72) among those in the third (moderate) risk stratum and 0.41 (95% CI, 0.32-0.53) among those in the fifth (highest) risk stratum. The association of nMAb treatment with reduced risk of hospitalizations within 14 days was strongest during the Delta variant epoch (OR, 0.37; 95% CI, 0.31-0.43) but not during the Omicron BA.1 epoch (OR, 1.29; 95% CI, 0.68-2.47). These findings were corroborated in the subset of patients with viral genomic data. Treatment with nMAbs was associated with a significant mortality benefit in all variant epochs (pre-Delta: OR, 0.16 [95% CI, 0.08-0.33]; Delta: OR, 0.14 [95% CI, 0.09-0.22]; Delta and Omicron BA.1: OR, 0.10 [95% CI, 0.03-0.35]; and Omicron BA.1: OR, 0.13 [95% CI, 0.02-0.93]). Potential adverse drug events were identified in 38 treated patients (0.2%).Conclusions and RelevanceIn this study, nMAb treatment for COVID-19 was safe and associated with reductions in ED visits, hospitalization, and death, although it was not associated with reduced risk of hospitalization during the Omicron BA.1 epoch. These findings suggest that targeted risk stratification strategies may help optimize future nMAb treatment decisions.

Cladding-pumped Raman lasers have often been cited for their potential for brightness enhancement, but so far have never achieved high power and beam quality simultaneously. By utilizing a fiber geometry with a larger cladding to core ratio than current high power Raman fiber lasers for brightness enhancement (BE-RFLs), a noise-seeded Raman fiber laser pumped by a 100 ns pulsed laser with record beam quality is achieved with M2=1.3 and 0.4 mJ first Stokes output, with an instantaneous brightness enhancement of 60. The results here support the hypothesis that the limiting factor to high beam quality in BE-RFLs is Raman conversion in the pump cladding, rather than higher order core modes as in most conventional fiber lasers.

Karst geology is characterized by the presence of sinkholes and voids, which may pose significant risk to existing infrastructure. Sinkhole formation is often observed near active quarries, where dewatering operations can alter regional groundwater flow patterns leading to subsidence and increased void formation. In these areas, identifying locations which may be susceptible to sinkhole formation requires an ability to map dissolution features within the rock. Traditional geotechnical explorations alone are not well-suited to this effort as they only provide subsurface information at discrete points and therefore may miss voids within the rock. Geophysical methods offer a means to produce continuous profiles of the rock surface and possible locations for voids but interpreting the results of these tests in karstic geology can be challenging. This study uses 2D electrical resistivity and seismic surveys at a site with previous sinkhole activity along an interstate in central Alabama. The site is adjacent to a limestone quarry. Resistivity data is collected using 2D dipole-dipole and strong-gradient arrays. The seismic data is processed using a full waveform inversion (FWI) technique. Subsurface profiles interpreted from the geophysical surveys are then compared to borehole data from previous site investigations. Results from the geophysical surveys are found to be consistent with borehole data regarding variation of bedrock depth and identification of possible sinkhole features. Potential limitations and sources of error pertaining to each survey type are considered.

BACKGROUND The expansion of telehealth use during the COVID-19 pandemic increased access to health care services for many US residents. This is particularly true for provider-to-patient telehealth communication. In rural communities, telehealth can increase access to health care services that would otherwise be limited due to geographic and distance barriers. The adoption of telehealth in rural communities, however, has been hindered by technology barriers, lack of community awareness, and lack of provider buy-in. The purpose of this study was to explore community-identified approaches to improving telehealth access in rural North Central Washington. OBJECTIVE The aim of this study was to identify, group, and rate approaches to expanding and integrating telehealth in rural communities in North Central Washington. METHODS We used group concept mapping, a participant-engaged, mixed method approach, to explore participant perspectives and preferences. Purposively sampled participants were community leaders and stakeholders in rural North Central Washington. Participants brainstormed strategies for implementing and expanding community telehealth access in their community and sorted them into conceptually similar groups. Strategies were then rated by participants in terms of potential impact, feasibility, and the cost of implementation. Quantitative analyses included multidimensional scaling and hierarchical cluster analysis to produce a cluster map and pattern match graph for interpreting the community members’ ideas and preferences. RESULTS Participant brainstorming yielded 70 strategies for implementing telehealth in rural North Central Washington. Strategies were individually sorted into groups (point map stress value 0.21), producing a 6-cluster solution. The clusters were “Community infrastructure,” “Ensuring access to telehealth technology,” “Technology infrastructure for telehealth,” “Training/awareness of telehealth,” “State- and policy-level considerations,” and “Health care systems engagement and delivery.” Participants rated “Training/awareness of telehealth” and “Health care systems engagement and delivery” to be highly impactful and feasible approaches. The “Training/awareness of telehealth” cluster included strategies such as educating community members that telehealth is an easy, reliable, convenient, and private way to access health care and providing community training on how to access health care remotely. The latter cluster, “Health care systems engagement and delivery,” included approaches that were ranked as highly feasible and impactful, such as engaging with clinics and providers on overcoming barriers to implementing telehealth services or ensuring that local health clinic staff is on board with telehealth as an alternative platform to provide services. CONCLUSIONS Strategies identified and rated by participants incorporate the importance of community engagement in telehealth implementation, including educating community members about telehealth and engaging with community health clinics to facilitate use by providers. Community partners in North Central Washington will use these findings, along with additional community survey data, broadband speed test data, and provider input, to increase access to telehealth in their rural and remote communities.

Fox Glacier/Te Moeka o Tuawe is a fast-responding maritime glacier that has undergone multiple advance and retreat phases during recent decades. Here we use a combination of repeat photography, Str...

Glaciers are unique indicators of climate change. While recent global-scale glacier decline has been attributed to anthropogenic forcing, direct links between human-induced climate warming and extreme glacier mass-loss years have not been documented. Here we apply event attribution methods to document this at the regional scale, targeting the highest mass-loss years (2011 and 2018) across New Zealand’s Southern Alps. Glacier mass balance is simulated using temperature and precipitation from multiple climate model ensembles. We estimate extreme mass loss was at least six times (2011) and ten times (2018) (>90% confidence) more likely to occur with anthropogenic forcing than without. This increased likelihood is driven by present-day temperatures ~1.0 °C above the pre-industrial average, confirming a connection between anthropogenic emissions and high annual ice loss. These results suggest that as warming and extreme heat events continue and intensify, there will be an increasingly visible human fingerprint on extreme glacier mass-loss years in the coming decades. Detecting a human role in a given year of extreme glacier mass loss is difficult at regional scales. Event attribution methods estimate that two extreme mass-loss years in the New Zealand Southern Alps, 2011 and 2018, were at least six and ten times more likely with anthropogenic climate warming.

Wide adoption of electronic health records (EHRs) has raised the expectation that data obtained during routine clinical care, termed “real-world” data, will be accumulated across health care systems and analyzed on a large scale to produce improvements in patient outcomes and the use of health care resources. To facilitate a learning health system, EHRs must contain clinically meaningful structured data elements that can be readily exchanged, and the data must be of adequate quality to draw valid inferences. At the present time, the majority of EHR content is unstructured and locked into proprietary systems that pose significant challenges to conducting accurate analyses of many clinical outcomes. This article details the current state of data obtained at the point of care and describes the changes necessary to use the EHR to build a learning health system.

We track the progression of height-integrated conductances over the course of an average substorm in a narrow local time sector of the nightside polar cap. These conductances are calculated from the mean energy flux and energy flux of precipitation, as estimated from a ratio of auroral emissions of the Lyman-Birge-Hopfield long and short band obtained by multiple polar region crossings of the Defence Meteorological Satellite Program F16, F17, and F18 spacecraft. Contributing auroral emission data span 1 January 2005 to 31 December 2017. Both Pedersen and Hall conductances are considered, as well as the influence of the magnetic latitude of substorm onset. Substorm onset times and magnitudes are provided by the SuperMAG network and SOPHIE substorm lists. We compare superimposed epoch ordered conductances with similarly averaged field aligned currents from the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE). Shortly before onset, conductances increase in a low latitude region, before an increase in conductance seen at all latitudes at the time of onset. The energy flux is shown to peak quickly after substorm onset, followed by mean energy. The conductances, energy flux, and mean energy are ordered by magnetic latitude of substorm onset, so that the lowest onset latitudes correspond to the highest value of any given parameter. Conductances recover quicker to pre-substorm levels for those substorms with higher onset magnetic latitudes.

Subauroral polarization streams (SAPS) typically refer to an enhanced westward plasma flow channel in the duskside subauroral ionosphere. SAPS overlap with the low-latitude part of downward Region-2 field-aligned currents (FACs). The relatively low subauroral conductance in this region requires a strong electric field for current closure, which drives the fast sunward plasma flow. Observations have shown dynamic variability of SAPS under various solar wind and interplanetary magnetic field (IMF) conditions, which are related to the variability of FACs and auroral precipitation, as well as their source regions in the ring current and plasmasheet. In this study, we use satellite observations and numerical simulations with the state-of-the-art Multiscale Atmosphere Geospace Environment (MAGE) model to investigate: 1) The role of diffuse electron precipitation in the formation of SAPS; 2) SAPS variability under IMF BY; and 3) Dawnside (as opposed to the more conventional duskside) SAPS as a unique feature of major geomagnetic storms. With data-model comparison, we will demonstrate that SAPS result from the different behaviors of ring current ions and plasma sheet electrons, and the corresponding self-consistent response of the ionosphere-thermosphere system via electrodynamic and particle coupling with the magnetosphere. We conclude that SAPS distribution and variability represent a fundamental feature of the geospace response to solar disturbances during storm time.

Glaciers in every region on Earth have lost mass over the past two decades as global temperature has risen 0.5C. Retreating glaciers symbolize climate change and present societal challenges across the globe. To better quantify the consequences of climate change, previous studies have established methods to calculate the anthropogenic component of extreme weather and climate events. Previously, we established a framework using existing event attribution methods together with glacier mass balance modeling to determine the increase in probability of extreme annual mass loss of New Zealand glaciers occurring with climate change. Here, we look to expand our developed attribution framework to calculate the change in probability and amount of extreme annual mass loss for glaciers around the world. To do this, we simulate glacier mass balance using a degree-day model, driven with general circulation model (GCM) output from available CMIP6 models and ensemble members. Historical natural simulations define climate without anthropogenic forcing, and SSP5 8.5 simulations define climate with anthropogenic forcing. We use the two different climate forcings to produce scenarios of glacier mass change with and without climate change. The differences in these scenarios are compared with measurements from the highest annual glacier mass loss years. We develop the attribution method though application to several glaciers around the world, including South Cascade Glacier (USA), Gries Glacier (Switzerland), and Brewster Glacier (New Zealand). Our initial results show large increases in probability and amount of annual glacier mass loss occurring due to climate change for all three glaciers. Difficulties in applying the attribution framework to glaciers globally include accessing modern glacier outlines and reconciling differences between glaciological and geodetic measurements of glacier mass change.

We quantify the contributions of different convection states to the magnetic flux through-put of the magnetosphere during 2010. To do this we provide a continuous classification of convection state for the duration of 2010 based upon observations of the solar wind and interplanetary magnetic field, geomagnetic indices, and field-aligned currents measured by the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE). Convection states are defined as 1) quiet and 2) weak activity, substorm 3) growth, 4) expansion, and 5) recovery phases, 6) substorm driven phase (when relatively steady magnetospheric convection occurs), 7) recovery bays (when recovery phase is accompanied by a negative excursion of the AL electrojet index), and 8) periods of multiple intensifications (storm-time periods when continuous short-period AL activity occur). The magnetosphere is quiet for 46% of the time, when very little convection takes place. The majority of convection occurs during growth and driven phases (21% and 38%, respectively, of open magnetic flux accumulation by dayside reconnection). We discuss these results in the context of the expanding/contracting polar cap model of convection, and describe a framework within which isolated substorms and disturbances during periods of more continuous solar wind-magnetosphere driving can be understood.

The Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) has revolutionized the way in which we can study the electrical current systems present over the poles of Earth. With high cadence measurements taken in both hemispheres, the data has proven invaluable in developing our understanding of the current systems that couple the magnetosphere and ionosphere and how they change in response to space weather. By employing the AMPERE data set, we aim to offer new insights into the complex and dynamic region 1 and region 2 current systems as they respond to the impact of solar wind disturbances on the magnetosphere and the driving of geomagnetic storms.We investigate the relationship between the hemispherically-integrated current flowing into or out of each pole and upstream solar wind parameters to understand how these currents are driven. As expected, current magnitude increases with increasing interplanetary magnetic field strength and solar wind speed. A key aim of the analysis is to determine if current magnitude saturates under strongly driven conditions, in the same way that the cross-polar cap potential is known to saturate. We present preliminary results, indicating a variety of behaviours at high driving, and discuss these in terms of theories of solar wind-magnetosphere coupling.

Despite our best intentions, physically salient but entirely task-irrelevant stimuli can sometimes capture our attention. With learning, it is possible to more efficiently ignore such stimuli, although specifically how the visual system accomplishes this remains to be clarified. Using a sample of young-adult participants, we examined the time course of eye movements to targets and distractors. We replicate a reduced frequency of eye movements to the distractor when appearing in a location at which distractors are frequently encountered. This reduction was observed even for the earliest saccades, when selection tends to be most stimulus-driven. When the distractor appeared at the high-probability location, saccadic reaction time was slowed specifically for distractor-going saccades, suggesting a slowing of priority accumulation at this location. In the event that the distractor was fixated, disengagement from the distractor was also faster when it appeared in the high-probability location. Both proactive and reactive mechanisms of distractor suppression work together to minimize attentional capture by frequently-encountered distractors.

Slope failures in high plasticity clay deposits are common occurrences in many parts of the world. In western and central Alabama, expansive Prairie clays are commonly found, and shallow slope failures have occurred in both fill and cut slopes containing these high plasticity clays. The objective of this study was to examine the effects of suction and the use of nonlinear strength envelopes on the embankment stability of a section of highway AL-5. The testing program consisted of fifteen ring shear tests performed using a Bromhead Ring Shear Device. The results of the tests were used to develop both linear and nonlinear fully softened and residual strength envelopes. The saturated strength envelopes are then used in a limit equilibrium slope stability analysis with and without the effects of suction. The results show stability (factor of safety &gt, 1) for all cases except the residual friction angle without suction. Given these results, large slope failures are unlikely to occur in this area, but surficial failures and deformations due to creep may be possible. These results demonstrate the importance of considering the effects of suction and nonlinear strength envelopes when examining the potential for shallow slope failures in high plasticity clays.

Slope failures in roadway embankments are common occurrences and can lead to traffic disruptions and large costs to repair damage. In areas with high-plasticity clays, special attention must be paid to characterizing both the stratigraphy and the potential for strength loss. This study demonstrates the use of an integrated site characterization approach, which seeks to utilize results from geotechnical and geophysical tests to understand the behavior of a landslide in west Alabama. The timing and mechanism of the initial failure causing the preexisting shear plane at this site are not known. Results from electrical resistivity and seismic geophysical tests are integrated with information from borings and index tests to develop a representative cross-section for the landslide, and torsional ring shear results are used to measure the drained fully softened and residual strengths. Both the limit equilibrium (LEM) and strength reduction method (SRM) analyses are used to examine possible failure mechanisms. The results show good agreement between noncircular LEM and SRM analyses and indicate that the initial failure was likely due to undrained loading of the clay. Analyses utilizing the residual drained strength envelopes produce FS values significantly lower than 1 indicating the slope to be unstable when soil on the failure plane exists at the residual state. Sensitivity analyses suggest that the combined effect of lowering the water table and strength recovery may explain the intermittent nature of movements.

Reinventing the humanoid character build pipeline at Blue Sky Studios presented several opportunities to create synergy between different processes, all centering around the concept of creating and maintaining a standardized Universal Mesh. The automation of rig argument placement, the building of rigging tools that use aspects of character geometry as inputs, the separation of character data from assets, and the creation of a stylized simulation-based approach to deform animated characters were all influenced by this base Universal Mesh. Ultimately, this approach offered new ways to get the most out of our character pipeline.

Importance: This three-part study characterizes the widespread implementation of telehealth during the first year of the COVID-19 pandemic, giving us insight into the role of telehealth as we enter a stage of “new normal” healthcare delivery in the U.S. Objective: The COVID-19 Telehealth Impact Study was designed to describe the natural experiment of telehealth adoption during the pandemic. Using a large claims data stream and surveys of providers and patients, we studied telehealth in all 50 states to inform healthcare leaders. Design, Setting, Participants: In March 2020, the MITRE Corporation and Mayo Clinic founded the COVID-19 Healthcare Coalition (C19HCC), to respond to the pandemic. We report trends using a dataset of over 2 billion healthcare claims covering over 50% of private insurance activity in the U.S. (January 2019-December 2020), along with key elements from our provider survey (July-August 2020) and patient survey (November 2020 - February 2021). Main Outcomes and Measures: There was rapid and widespread adoption of telehealth in Spring 2020 with over 12 million telehealth claims in April 2020, accounting for 49.4% of total health care claims. Providers and patients expressed high levels of satisfaction with telehealth. 75% of providers indicated that telehealth enabled them to provide quality care. 84% of patients agreed that quality of their telehealth visit was good. Results: Peak levels of telehealth use varied widely among states ranging from 74.9% in Massachusetts to 25.4% in Mississippi. Every clinical discipline saw a steep rise with the largest claims volume in behavioral health. Provision of care by out-of-state provider was common at 6.5% (October-December 2020). Providers reported multiple modalities of telehealth care delivery. 74% of patients indicated they will use telehealth services in the future. Conclusions and Relevance: Innovation shown by providers and patients during this period of rapid telehealth expansion constitutes a great natural experiment in care delivery with evidence supporting widespread clinical adoption and satisfaction on the part of both patients and clinicians. The authors encourage continued broad access to telehealth over the next 12 months to allow telehealth best practices to emerge, creating a more effective and resilient system of care delivery.

OBJECTIVE To examine the role of intensive care unit (ICU) management following lateral skull base surgery for vestibular schwannoma and identify risk factors for complications warranting admission to the ICU. STUDY DESIGN Retrospective review. SETTING Tertiary referral center. PATIENTS Two hundred consecutive patients undergoing lateral skull base surgery for vestibular schwannomas. INTERVENTION Lateral skull base approach for resection of vestibular schwannoma and postoperative monitoring. MAIN OUTCOME MEASURES Patients were grouped if they sustained an ICU complication, a non-ICU complication, or no complication. Analysis was performed to determine patient or treatment factors that may be associated with ICU complications. Multivariate and three-way analysis of variance compared groups, and multivariate logistic regression determined adjusted odds ratios (aOR) for analyzed factors. RESULTS Seventeen of 200 patients sustained ICU complications (8.5%), most commonly hypertensive urgency (n = 15). Forty-six (23%) sustained non-ICU complications, and 137 (68.5%) had no complications. When controlling for age, sex, obesity, and other comorbidities, only hypertension (aOR 5.43, 95% confidence interval (CI) 1.35-21.73, p = 0.017) and tumor volume (aOR 3.29, 95% CI 1.09-9.96, p = 0.035) were independently associated with increased risk of ICU complications. CONCLUSIONS The necessity of intensive care following lateral skull base surgery is rare, with the primary ICU complication being hypertensive urgency. Preoperative hypertension and large tumor volume (>4500 mm3) were independently associated with increased risk for ICU complications. These findings may allow for risk stratification of patients appropriate for admission to stepdown units following resection of vestibular schwannomas. Further prospective, multi-center, randomized studies are necessary to validate these findings before systematic changes to current postoperative care practices.

In 1995, a geotechnical experimentation site was established in rural Lee County, Alabama near the area often referred to as Spring Villa. The Auburn University National Geotechnical Experimentation Site (AUNGES) site is situated near the southern terminus of the Appalachian Piedmont Physiographic province. The site consists of two sub sites, one that is a thick profile of residual soil and the other is an outcrop of fractured weathered quartzite. Extensive site investigation has been conducted at the site by many agencies and researchers using a wide array of in-situ soil tests. Foundations, excavations, and retaining structures have been constructed and load tested at the AUNGES. This paper summarizes all the work conducted at the site since its inception. Maps that detail the location of all in-situ tests and structures tested were generated. Representative profiles are included that relate early site investigation, between 1995 and 2005, and contemporary work done after 2010 are generated based on the results of piezocone, dilatometer, standard penetration, and shear wave velocity tests.

Two excavations were instrumented at the Auburn National Geotechnical Experimentation Site (NGES) in Opelika, AL. The excavations were constructed approximately 6 m deep × 30 m long with a vertical face. The primary goal of this experiment was to determine the boundary conditions that resulted in failure of the excavation. In doing so, conclusions were drawn regarding the accuracy of common laboratory test methods for estimating the strength properties of residual soil. The instrumentation plan was designed to monitor real-time pore water pressures (positive and negative) surrounding the excavation throughout the course of each 1-year test period. Time-lapse cameras were used to identify when failures occurred, and the approximate geometry of the failure planes. Undisturbed soil samples were taken during the subsurface exploration and used in conjunction with previous soil test results to accurately define the material properties and layering based on common laboratory test methods. In addition to common laboratory tests, unsaturated triaxial tests were also conducted, and soil-water characteristic curves were measured to further define the unsaturated properties of the soil. In both excavations, failure was observed along a similar plane, which began at the bottom of the excavation, and propagated to the surface (approximately 2 m behind the face of the excavation) along existing tension cracks that developed during the construction of the excavation. Based on these results, recommendations are provided as related to the most appropriate test methods for determining the strength properties of residual soil for use in geotechnical design.

The Standing Committee on Foundations for Bridges and Other Structures has supported the implementation of the load and resistance factors (LRFD) design philosophy into practice. The committee has contributed by hosting discussions on the advantages, issues, and impact of the implementation of the American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) into foundation design and other related fields. The background and a historical overview of the development of LRFD in bridge foundation design are presented in this paper. Several National Cooperative Highway Research Program (NCHRP) projects have been of paramount importance on this matter. Milestone research projects are described, and a perspective on the future of the field is drawn. This document is intended to be a roadmap through the most useful material to understand reliability analysis and its application to geotechnical engineering. It is intended to be of interest to those engineers charged with performing reliability-based calibration in need of a starting point. The primary literature and steps followed to develop the current AASHTO LRFD specifications are highlighted. This paper aims to contribute to the understanding and future improvement of the LRFD specifications.

Background The expansion of telehealth use during the COVID-19 pandemic increased access to health care services for many US residents. This is particularly true for provider-to-patient telehealth communication. In rural communities, telehealth can increase access to health care services that would otherwise be limited due to geographic and distance barriers. The adoption of telehealth in rural communities, however, has been hindered by technology barriers, lack of community awareness, and lack of provider buy-in. The purpose of this study was to explore community-identified approaches to improving telehealth access in rural North Central Washington. Objective The aim of this study was to identify, group, and rate approaches to expanding and integrating telehealth in rural communities in North Central Washington. Methods We used group concept mapping, a participant-engaged, mixed method approach, to explore participant perspectives and preferences. Purposively sampled participants were community leaders and stakeholders in rural North Central Washington. Participants brainstormed strategies for implementing and expanding community telehealth access in their community and sorted them into conceptually similar groups. Strategies were then rated by participants in terms of potential impact, feasibility, and the cost of implementation. Quantitative analyses included multidimensional scaling and hierarchical cluster analysis to produce a cluster map and pattern match graph for interpreting the community members’ ideas and preferences. Results Participant brainstorming yielded 70 strategies for implementing telehealth in rural North Central Washington. Strategies were individually sorted into groups (point map stress value 0.21), producing a 6-cluster solution. The clusters were “Community infrastructure,” “Ensuring access to telehealth technology,” “Technology infrastructure for telehealth,” “Training/awareness of telehealth,” “State- and policy-level considerations,” and “Health care systems engagement and delivery.” Participants rated “Training/awareness of telehealth” and “Health care systems engagement and delivery” to be highly impactful and feasible approaches. The “Training/awareness of telehealth” cluster included strategies such as educating community members that telehealth is an easy, reliable, convenient, and private way to access health care and providing community training on how to access health care remotely. The latter cluster, “Health care systems engagement and delivery,” included approaches that were ranked as highly feasible and impactful, such as engaging with clinics and providers on overcoming barriers to implementing telehealth services or ensuring that local health clinic staff is on board with telehealth as an alternative platform to provide services. Conclusions Strategies identified and rated by participants incorporate the importance of community engagement in telehealth implementation, including educating community members about telehealth and engaging with community health clinics to facilitate use by providers. Community partners in North Central Washington will use these findings, along with additional community survey data, broadband speed test data, and provider input, to increase access to telehealth in their rural and remote communities. Conflicts of Interest None declared.

The land ice contribution to global mean sea level rise has not yet been predicted 1 using ice sheet and glacier models for the latest set of socio-economic scenarios, nor using coordinated exploration of uncertainties arising from the various computer models involved. Two recent international projects generated a large suite of projections using multiple models 2–8, but primarily used previous-generation scenarios 9 and climate models 10, and could not fully explore known uncertainties. Here we estimate probability distributions for these projections under the new scenarios 11,12 using statistical emulation of the ice sheet and glacier models. We find that limiting global warming to 1.5 degrees Celsius would halve the land ice contribution to twenty-first-century sea level rise, relative to current emissions pledges. The median decreases from 25 to 13 centimetres sea level equivalent (SLE) by 2100, with glaciers responsible for half the sea level contribution. The projected Antarctic contribution does not show a clear response to the emissions scenario, owing to uncertainties in the competing processes of increasing ice loss and snowfall accumulation in a warming climate. However, under risk-averse (pessimistic) assumptions, Antarctic ice loss could be five times higher, increasing the median land ice contribution to 42 centimetres SLE under current policies and pledges, with the 95th percentile projection exceeding half a metre even under 1.5 degrees Celsius warming. This would severely limit the possibility of mitigating future coastal flooding. Given this large range (between 13 centimetres SLE using the main projections under 1.5 degrees Celsius warming and 42 centimetres SLE using risk-averse projections under current pledges), adaptation planning for twenty-first-century sea level rise must account for a factor-of-three uncertainty in the land ice contribution until climate policies and the Antarctic response are further constrained.

Mountain glacier moraine sequences and their chronologies allow us to evaluate the timing and climate conditions that underpin changes in the equilibrium line altitudes (ELAs), which can provide valuable information on the paleoclimatology of understudied regions such as tropical East Africa. However, moraine sequences are inherently discontinuous, and the precise climate conditions that they represent can be ambiguous due to the sensitivity of mountain glaciers to temperature, precipitation, and other environmental variables. Here, we used a two-dimensional (2-D) ice-flow and mass-balance model to simulate glacier extents and ELAs in the Rwenzori Mountains in East Africa over the past 31,000 yr (31 k.y.), including the Last Glacial Maximum (LGM), late glacial period, and the Holocene Epoch. We drove the glacier model with two independent, continuous temperature reconstructions to simulate possible glacier length changes through time. Model input paleoclimate values came from branched glycerol dialkyl glycerol tetraether (brGDGT) temperature reconstructions from alpine lakes on Mount Kenya for the last ~31 k.y., and precipitation reconstructions for the LGM came from various East African locations. We then compared the simulated fluctuations with the positions and ages (where known) of the Rwenzori moraines. The simulated glacier extents reached within 1.1 km of the dated LGM moraines in one valley (93% of the full LGM extent) when forced by the brGDGT temperature reconstructions (maximum cooling of 6.1 °C) and a decrease in precipitation (−10% than modern amounts). These simulations suggest that the Rwenzori glaciers required a cooling of at least 6.1 °C to reach the dated LGM moraines. Based on the model output, we predict an age of 12–11 ka for moraines located halfway between the LGM and modern glacier extents. We also predict ice-free conditions in the Rwenzori Mountains for most of the early to middle Holocene, followed by a late Holocene glacier readvance within the last 2000 yr.

Stimulated Brillouin scattering (SBS) is typically the lowest order nonlinearity encountered in ytterbium doped fiber amplifiers (YDFA), and the simplest means of suppressing it is though linewidth broadening from phase modulation. However, to maintain compatibility with beam combining techniques critical to scaling to high output powers, narrow linewidths are needed, and bandwidth efficient means of suppressing SBS are key to scaling to high powers. Here, the scalability of novel phase modulation techniques in combination with laser gain competition are explored. Ultimately, LGC is shown to improve the TMI threshold by 15%, and reduce the linewidth by a factor of 2.1. A 1.8 kW fiber amplifier with 7 Ghz linewidth is demonstrated.