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During minor to moderate geomagnetic storms, caused by corotating interaction regions (CIRs) at the leading edge of high-speed streams (HSSs), solar wind Alfven waves modulated the magnetic reconnection at the dayside magnetopause. The Resolute Bay Incoherent Scatter Radars (RISR-C and RISR-N), measuring plasma parameters in the cusp and polar cap, observed ionospheric signatures of flux transfer events (FTEs) that resulted in the formation of polar cap patches. The patches were observed as they moved over the RISR, and the Canadian High-Arctic Ionospheric Network (CHAIN) ionosondes and GPS receivers. The coupling process modulated the ionospheric convection and the intensity of ionospheric currents, including the auroral electrojets. The horizontal equivalent ionospheric currents (EICs) are estimated from ground-based magnetometer data using an inversion technique. Pulses of ionospheric currents that are a source of Joule heating in the lower thermosphere launched atmospheric gravity waves, causing traveling ionospheric disturbances (TIDs) that propagated equatorward. The TIDs were observed in the SuperDual Auroral Radar Network (SuperDARN) high-frequency (HF) radar ground scatter and the detrended total electron content (TEC) measured by globally distributed Global Navigation Satellite System (GNSS) receivers. Canada Foundation for Innovation; New Brunswick Innovation Foundation; national scientific funding agency of Australia; national scientific funding agency of Canada; national scientific funding agency of China; national scientific funding agency of France; national scientific funding agency of Italy; national scientific funding agency of Japan; national scientific funding agency of Norway; national scientific funding agency of South Africa; national scientific funding agency of United Kingdom; national scientific funding agency of United States of America; NSF [AGS-1934997]; National Science Foundation [AGS-1935110]; Canadian Space Agency; Province of Saskatchewan; Canadian Space Agency/Geospace Observatory (GO) Canada program, Athabasca University, Centre for Science/Faculty of Science and Technology; US National Science Foundation [ATM-0827903]; Magnetospheric Physics Program of National Science Foundation [AGS-0245139]; Canadian Space Agency [9 F007-071429, 9 F007-070993]; CSA [21SUSTCHAI]; United Kingdom Natural Environment Research Council (NERC) [NE/W003147/1, NE/W003368/1]; NASA [80NSSC18K0570, 80NSSC18K1220, 80GSFC17C0018, NAS5-02099] Published version Infrastructure funding for CHAIN was provided by the Canada Foundation for Innovation and the New Brunswick Innovation Foundation. CHAIN operation is conducted in collaboration with the Canadian Space Agency (CSA). Contributions by the ACE (Norman F. Nees at Bartol Research Institute, David J. McComas at SWRI), Geotail (Susumu Kokubun at STELAB Nagoya University), Wind spacecraft teams, NASA's SPDF/CDAWeb, and the NSSDC OMNIWeb are acknowledged. RISR-C is funded by the Canada Foundation for Innovation and led by the University of Calgary, University of Saskatchewan, Athabasca University, and SRI International. The authors acknowledge the use of SuperDARN data. SuperDARN is a collection of radars funded by the national scientific funding agencies of Australia, Canada, China, France, Italy, Japan, Norway, South Africa, United Kingdom, and the United States of America. The Christmas Valley SuperDARN radars are maintained and operated by Dartmouth College under support by NSF grant AGS-1934997. Operations of the Goose Bay, Kapuskasing, and Blackstone SuperDARN radars are supported by the National Science Foundation under award AGS-1935110. The operation of the Saskatoon radar is supported by the Canada Foundation for Innovation, the Canadian Space Agency, and the Province of Saskatchewan. We thank the many different groups operating magnetometer arrays for providing data for this study, including the THEMIS UCLA magnetometer network (Ground-based Imager and Magnetometer Network for Auroral Studies). The AUTUMNX magnetometer network is funded through the Canadian Space Agency/Geospace Observatory (GO) Canada program, Athabasca University, Centre for Science/Faculty of Science and Technology. The Magnetometer Array for Cusp and Cleft Studies (MACCS) array is supported by the US National Science Foundation grant ATM-0827903 to Augsburg College. The Solar and Terrestrial Physics (STEP) magnetometer file storage is at the Department of Earth and Planetary Physics, University of Tokyo and maintained by Kanji Hayashi (hayashi@grl.s.u-tokyo.ac.jp).The McMAC Project is sponsored by the Magnetospheric Physics Program of National Science Foundation through grant AGS-0245139. The ground magnetic stations are operated by the Technical University of Denmark, National Space Institute (DTU Space). The Canadian Space Science Data Portal is funded in part by the Canadian Space Agency contract numbers 9 F007-071429 and 9 F007-070993. The Canadian Magnetic Observatory Network (CANMON) is maintained and operated by the Geological Survey of Canada. David R. Themens's contribution to this work is supported in part through CSA grant no. 21SUSTCHAI and through the United Kingdom Natural Environment Research Council (NERC) EISCAT3D: Fine-scale structuring, scintillation, and electrodynamics (FINESSE) (NE/W003147/1) and DRivers and Impacts of Ionospheric Variability with EISCAT-3D (DRIIVE) (NE/W003368/1) projects. James M. Weygand acknowledges NASA grant: 80NSSC18K0570, 80NSSC18K1220, NASA contract: 80GSFC17C0018 (HPDE), NAS5-02099(THEMIS). Shibaji Chakraborty thanks the National Science Foundation for support under grant AGS-1935110.

The Sustainable Development Goal (SDG) target for access to safe sanitation and hygiene represents a marked improvement over the target used during the Millennium Development Goal (MDG) period. The SDG target attempts to: explicitly address hygiene; eliminate inequalities within populations; evaluate sanitation services beyond the household; account for the accessibility, safety, acceptability, and affordability of service delivery; and improve the sustainability of services (WHO/UNICEF, 2015). However, the proposed indicators for monitoring progress in sanitation and hygiene still rely primarily on infrequent household surveys and census data. This paper provides a critical review of the sanitation and hygiene target and explores the potential gaps between the expanded understanding of access, the proposed monitoring strategies, and the desired impacts. A variety of innovative methodologies and technologies are reviewed, with specific attention given to their suitability for measuring and monitoring progress towards the sanitation and hygiene target.

The second law of thermodynamics explains the dissipative nature of embryonic development as an exchange of energy-dependent order for proportionately greater output of heat and waste. Recent work on granular matter provides a path by which to define the roles of passive, stochastic mechanisms in nonequilibrium systems. Here, we apply such a framework to examine the role of thermodynamic parameters to cell ingression, the movement of cells from one tissue layer to another that has been attributed, in part, to directional cues. Using the murine neural crest as a model system, we provide evidence that a stochastic mechanism, rather than a proposed stiffness gradient, underlies cell ingression. Cortical fluctuations representing effective temperature and cell packing configurations generate an entropic trap that promotes cell ingression. The results imply dissipative mechanisms that transiently disorder tissue underlie some morphogenetic events.

The potential use of cannabidiol (CBD) as a nutraceutical to support improved health and welfare has been of increasing interest. In particular, CBD has been shown to decrease anxiety in humans and small animals. While there is little research published on the effects of CBD supplementation in horses, its use is increasing rapidly. The objective of this study was to determine the effect of feeding a pelleted CBD supplement on equine reactivity and heart rate (HR). Seventeen stock-type geldings were divided into control (CON) or treatment (TRT) groups. The TRT group received 100 mg of CBD once daily. Control horses were maintained on their standard diet without supplementation. A novel object test was used to evaluate changes in HR and reactivity before and after 6 weeks of supplementation. Heart rate was recorded before, at, and after exposure to the novel object. Reactivity when the horse was exposed to the novel object was scored live and through video review. There was no difference in starting, stimulus, or final HR, but TRT horses exhibited less reactivity after 6 weeks of supplementation. Results suggest that CBD supplementation may lower reactivity in horses.

The Super Dual Auroral Radar Network (SuperDARN) is a collection of radars built to study ionospheric convection. We use a 7-year archive of SuperDARN convection maps, processed in 3 different ways, to build a statistical understanding of dusk-dawn asymmetries in the convection patterns. We find that the data set processing alone can introduce a bias which manifests itself in dusk-dawn asymmetries. We find that the solar wind clock angle affects the balance in the strength of the convection cells. We further find that the location of the positive potential foci is most likely observed at latitudes of 78° for long periods (>300 min) of southward interplanetary magnetic field (IMF), as opposed to 74° for short periods (

Purpose Cardiac radioablation using stereotactic body radiation therapy is gaining popularity as a noninvasive treatment for otherwise refractory ventricular arrhythmias. As radiation oncologists might be unaccustomed to the lexicon used by cardiologists to describe the location of arrhythmogenic foci, a preliminary guide to cardiac-specific anatomy and orientation is needed to foster effective communication between the radiation oncologist and cardiology team. Methods and Materials Electrocardiogram-gated and respiratory-gated computed tomography imaging was acquired per institutional protocol. Additional relevant imaging modalities are described. The American Heart Association 17-segment model is described in detail because this framework is used frequently by cardiologists to describe the location left ventricular abnormalities. Results A step-by-step guide is provided for properly rotating the heart from standard orthogonal views obtained during radiation simulation to the cardiac-specific orientation needed to appreciate the 17-segment model. Once the proper configuration is achieved, the location of each segment is defined in detail. Conclusions This atlas serves as an introduction to the relevant anatomy and principles, and it provides a suggested approach to help delineate cardiac radioablation targets using the established American Heart Association 17-segment model.

Global engineers must be taught to consider the historical and present causes of persistent poverty and systematic barriers to prosperity. Such training will better inform the choices engineers make and help move the engineering sector away from a product and community-level focus towards working to address the root causes of poverty. A framing for Global Engineering has recently been proposed by the Mortenson Center in Global Engineering at the University of Colorado Boulder, building on over 15 years of curricular efforts. Global Engineering, as taught by the Mortenson Center, positions the field as a complement to Global Health and Development Economics while further embracing a historically contextualized and anti-colonial training.

Properly planned single isocenter volumetric modulated arc therapy (VMAT) radiosurgery plans exhibit high quality and efficiency. We report here the largest clinical experience to date, to our knowledge, comparing manual planning with a new automated platform designed to standardize and simplify radiosurgery planning and delivery processes.We treated 693 patients with single isocenter VMAT radiosurgical plans generated by either our conventional manual (mVMAT) or a recently implemented automated (HyperArcThe median Radiation Therapy Oncology Group (RTOG) conformity index was 1.14 and was not different between the 2 techniques. The median Paddick gradient index was 5.42 for HyperArc versus 7.09 for mVMAT (P.001). The median mean brain doses were 4.6% and 5.1% for HyperArc and mVMAT, respectively (P = .04). The PSQA for both techniques met clinical criteria, but 97% of the HyperArc plans satisfied the gamma tolerance limit recommended by the American Association of Physicists in Medicine Task Group No. 218, compared with 94% of the mVMAT plans (P = .02). The median treatment-planning times were not significantly different. The median treatment times were 10.5 and 11.4 minutes for HyperArc and mVMAT, respectively (P.001). The Kaplan-Meier estimate of local control was 90.1% at 1 year.HyperArc produces high-quality radiosurgical plans that are at least as good as mVMAT plans created by an expert manual planner with easier planning and more efficient delivery workflow. A less experienced planner can produce very high-quality radiosurgical plans even for patients with more than 10 targets. The use of a single-isocenter technique for multiple targets with no PTV margin did not compromise clinical outcomes, and 1-year local control for treated targets remained congruent with historical series.

Purpose For stereotactic radiosurgery (SRS), accurate evaluation of dose-volume metrics for small structures is necessary. The purpose of this study was to compare the DVH metric capabilities of five commercially available SRS DVH analysis tools (Eclipse, Elements, Raystation, MIM, and Velocity). Methods DICOM RTdose and RTstructure set files created using MATLAB were imported and evaluated in each of the tools. Each structure set consisted of 50 randomly placed spherical targets. The dose distributions were created on a 1-mm grid using an analytic model such that the dose-volume metrics of the spheres were known. Structure sets were created for 3, 5, 7, 10, 15, and 20 mm diameter spheres. The reported structure volume, V100% [cc], and V50% [cc], and the RTOG conformity index and Paddick Gradient Index, were compared with the analytical values. Results The average difference and range across all evaluated target sizes for the reported structure volume was - 4.73%[-33.2,0.2], 0.11%[-10.9, 9.5], -0.39%[-12.1, 7.0], -2.24%[-21.0, 1.3], and 1.15%[-15.1,0.8], for TPS-A through TPS-E, respectively. The average difference and range for the V100%[cc] (V20Gy[cc]) was - 0.4[-24.5,9.8], -2.73[-23.6, 1.1], -3.01[-23.6, 0.6], -3.79[-27.3, 1.3], and 0.26[-6.1,2.6] for TPS-A through TPS-E, respectively. For V50%[cc](V10Gy[cc]) in TPS-A through TPS-E the average and ranger were - 0.05[-0.8,0.4], -0.18[-1.2, 0.5], -0.44[-1.4, 0.3], -0.26[-1.8, 2.6], and 0.09[-1.4,2.7]. Conclusion This study expanded on the previously published literature to quantitatively compare the DVH analysis capabilities of software commonly used for SRS plan evaluation and provides freely available and downloadable analytically derived set of ground truth DICOM dose and structure files for the use of radiotherapy clinics. The differences between systems highlight the need for standardization and/or transparency between systems, especially when evaluating plan quality for multi-institutional clinical trials.

Increasingly, satellite-derived rainfall data is used for climate research and action in Africa. In this study, we use six years of rain gauge data from 596 stations operated by the Trans-African Hydro-Meteorological Observatory (TAHMO) to validate three gauge-calibrated satellite rainfall products – CHIRPS, TAMSAT and GSMaP_wGauge – and one satellite-only rainfall product – GSMaP. Validations are stratified to evaluate performance across the continent and in East Africa, Southern Africa, and West Africa at daily, pentadal, and monthly timescales. For daily mean rainfall over Africa, CHIRPS has the highest bias at 15.5 % (0.5 mm) whereas GSMaP_wGauge has the lowest bias at 0.02 mm (0.7 %). We find higher daily rainfall event detection scores in the GSMaP products than in CHIRPS or TAMSAT. Generally, for every two rainfall events predicted by CHIRPS and TAMSAT, the GSMaP products predict three or more events. The highest mean monthly biases are produced by CHIRPS in East Africa (29 %; 26.3 mm wet bias), TAMSAT in Southern Africa (13 %; 10.4 mm dry bias) and GSMaP in West Africa (23 %; 19.6 mm wet bias). Considerable biases in seasonal rainfall are observed in all sub-regions for every satellite product. There is an increase of 0.6–1.3 mm in satellite rainfall RMSE for a 1 km increase in elevation revealing the influence of elevation on rainfall estimation by satellite models. Overall, satellite-derived rainfall products have notable errors, while GSMaP products produce comparable or better results at multiple timescales relative to CHIRPS and TAMSAT.

A microwave plasma model of a chemical vapour deposition (CVD) reactor is presented for understanding spatial heteroepitaxial growth of polycrystalline diamond on Si. This work is based on the TM0(n>1)p clamshell style reactor (Seki Diamond/ASTEX SDS 6K, Carat CTS6U, ARDIS-100 style) whereby a simplified H_2 plasma model is used to show the radial variation in growth rate over small samples with different sample holders. The model uses several steps: an electromagnetic (EM) eigenfrequency solution, a frequency-transient EM/plasma fluid solution and transient a heat transfer solution at low and high microwave power density. Experimental growths provide model validation with characterisation using Raman spectroscopy and scanning electron microscopy. This work demonstrates that shallow holders result in non-uniform diamond films, with a radial variation akin to the electron density and temperature distribution at the wafer surface. For the same process conditions, greater homogeneity is observed for taller holders, however, if the height is too extreme, the diamond quality reduces. From a modelling perspective, EM solutions are limited but useful for examining electric field focusing at the sample edges, resulting in accelerated diamond growth. For better accuracy, plasma fluid and heat transfer solutions are imperative for modelling spatial growth variation., EDIT1: Title changed

What makes teams creative? We investigated how the diversity and agreeableness of team members moderate the relationship between creative self-efficacy (CSE) and innovative performance at the team ...

Purpose To report on the use of surface guided imaging during frameless intracranial stereotactic radiotherapy with automated delivery via HyperArcTM (Varian Medical Systems, Palo Alto, CA). Methods All patients received intracranial radiotherapy with HyperArcTM and were monitored for intrafraction motion by the AlignRT® (VisionRT, London, UK) surface imaging (SI) system. Immobilization was with the EncompassTM (Qfix, Avondale, PA) aquaplast mask device. AlignRT® log files were correlated with trajectory log files to correlate treatment parameters with SI reported offsets. SI reported offsets were correlated with gantry angle and analyzed for performance issues at non‐zero couch angles and during camera‐pod blockage during gantry motion. Demographics in the treatment management system were used to identify race and determine if differences in SI reported offsets are due to skin tone settings. Results A total of 981 fractions were monitored over 14 months and 819 were analyzed. The median AlignRT® reported motion from beginning to the end of treatment was 0.24 mm. The median offset before beam on at non‐zero couch angles was 0.55 mm. During gantry motion when camera pods are blocked, the median magnitude was below 1 mm. Median magnitude of offsets at non‐zero couch angles was not found to be significantly different for patients stratified by race. Conclusions Surface image guidance is a viable alternative to scheduled mid‐treatment imaging for monitoring intrafraction motion during stereotactic radiosurgery with automated delivery.

Infections with enteric pathogens impose a heavy disease burden, especially among young children in low-income countries. Recent findings from randomized controlled trials of water, sanitation, and hygiene interventions have raised questions about current methods for assessing environmental exposure to enteric pathogens. Approaches for estimating sources and doses of exposure suffer from a number of shortcomings, including reliance on imperfect indicators of fecal contamination instead of actual pathogens and estimating exposure indirectly from imprecise measurements of pathogens in the environment and human interaction therewith. These shortcomings limit the potential for effective surveillance of exposures, identification of important sources and modes of transmission, and evaluation of the effectiveness of interventions. In this review, we summarize current and emerging approaches used to characterize enteric pathogen hazards in different environmental media as well as human interaction with those media (external measures of exposure), and review methods that measure human infection with enteric pathogens as a proxy for past exposure (internal measures of exposure). We draw from lessons learned in other areas of environmental health to highlight how external and internal measures of exposure can be used to more comprehensively assess exposure. We conclude by recommending strategies for advancing enteric pathogen exposure assessments.

Recycling systems aboard spacecraft are currently limited to approximately 80% water recovery from urine. To address challenges associated with odors, contamination, and microgravity fluid flow phenomena, current systems use toxic pretreatment chemicals, filters, and rotary separators. Herein, a semipassive and potentially contaminant- and biofouling-free approach to spacecraft urine processing is developed by combining passive liquid–gas separation, nanophotonic pasteurization, and noncontact Leidenfrost droplet distillation. The system aims to achieve >98% water recovery from wastewater streams in zero, Lunar, Martian, and terrestrial gravitational environments. The surfaces of the phase separator are coated with carbon black nanoparticles that are irradiated by infrared light-emitting diodes (LEDs) producing hyperlocal heating and pasteurization during urine collection, separation, and storage. For the prescribed flow rate and timeline, the urine is then introduced into a heated 8.5-m-long helical hemicircular aluminum track. The low pitch and the high temperature of the track combine to establish weakly gravity-driven noncontact Leidenfrost droplet distillation conditions. In our technology demonstrations, salt-free distillate and concentrated brine are successfully recovered from saltwater feed stocks. We estimate equivalent system mass metrics for the approach, which compare favorably to the current water recovery system aboard the International Space Station.

Solar wind Alfvén waves [1] coupling to the magnetosphere-ionosphere-thermosphere (MIT) have been associated with high-intensity long-duration continuous auroral electrojet activity [2] and shown to modulate ionospheric convection in the cusp generating polar cap patches and atmospheric gravity waves [3,4]. The Resolute Bay Incoherent Scatter Radars (RISR-C and RISR-N) [5] are well suited for observing the ionospheric signatures of flux transfer events and subsequent polar patch formation in the cusp. During minor to moderate geomagnetic storms caused by corotating interaction regions at the leading edge of solar wind high speed streams polar patches were observed as they convected over the RISR, and the Canadian High-Arctic Ionospheric Network (CHAIN) ionosondes and GPS receivers [6]. The patches were generated by the MIT coupling of Alfvén waves in the upstream solar wind. The coupling process modulated the ionospheric convection and the intensity of ionospheric currents, including auroral electrojets. The horizontal equivalent ionospheric currents and vertical current amplitudes are estimated from the ground-based magnetometer data using an inversion technique [7]. Pulses of ionospheric currents that are a source of Joule heating in the lower thermosphere launched atmospheric gravity waves causing traveling ionospheric disturbances (TIDs) propagating equatorward. TIDs were observed in the SuperDARN HF radar ground scatter [8], in the detrended GPS TEC maps, and in one case, in the altitude profiles of ionospheric electron densities observed by the Poker Flat ISR [9].[1] Belcher, JW, Davis, L, Jr. 1971. J. Geophys. Res. 76, 3534–3563.[2] Tsurutani, BT, Gonzalez, WD. 1987. Planet. Space Sci. 35(4), 405–412.[3] Prikryl, P, et al., 1999. Ann. Geophys. 17, 463–489.[4] Prikryl, P, et al., 2005. Ann. Geophys. 23, 401–417.[5] Gillies RG, et al., 2016. Radio Sci., 51(10):1645-1659.[6] Jayachandran, PT, et al., 2009. Radio Sci., 44, RS0A03.[7] Weygand, JM, et al., 2011. J. Geophys. Res. 116, A03305.[8] Chisham, G., et al., 2007. Surv. Geophys. 28, 33–109.[9] Heinselman, CJ, Nicolls, MJ, 2008. Radio Sci., 43, RS5013.

The Super Dual Auroral Radar Network (SuperDARN) was built to study ionospheric convection and has in recent years been expanded geographically. Alongside software developments, this has resulted in many different versions of the convection maps data set being available. Using data from 2012 to 2018, we produce five different versions of the widely used convection maps, using limited backscatter ranges, background models and the exclusion/inclusion of data from specific radar groups such as the StormDARN radars. This enables us to simulate how much information was missing from older SuperDARN research. We study changes in the Heppner-Maynard boundary (HMB), the cross polar cap potential (CPCP), the number of backscatter echoes (n) and the χ2/n statistic which is a measure of the global agreement between the measured and fitted velocities. We find that the CPCP is reduced when the PolarDARN radars are introduced, but then increases again when the StormDARN radars are added. When the background model is changed from the RG96 model, to the most recent TS18 model, the CPCP tends to decrease for lower values, but tends to increase for higher values. When comparing to geomagnetic indices, we find that there is on average a linear relationship between the HMB and the geomagnetic indices, as well as n, which breaks when the HMB is located at latitudes below ∼50° due to the low observational density. Whilst n is important in constraining the maps (maps with n > 400 data points are unlikely to differ), it is insufficient as the sole measure of quality.

Seizure control after stereotactic radiosurgery (SRS) for arteriovenous malformations (AVMs) is an area of growing interest, with previous studies reporting up to 70% seizure freedom after treatment. The goals of this study were to identify specific patient and AVM characteristics associated with seizure presentation and seizure outcomes after SRS treatment.A retrospective review of consecutive patients undergoing SRS for brain AVMs between 2009 and 2019 at our institution was conducted. Chi-squared and logistic regression analyses were utilized to identify patient and AVM factors associated with preoperative seizure presentation and development of new onset seizures after SRS.Two hundred ten consecutive patients presenting with AVMs treated with SRS were reviewed. Factors associated with seizure presentation included larger AVM size (P = 0.02), superficial venous drainage (P 0.05), and parietal location (P = 0.04). Of 188 patients with follow-up (90%), 30 patients presented with seizures and 14 (47%) were seizure-free post-SRS. Of 158 patients presenting without seizure, 29 (18%) developed de novo seizures during follow-up. De novo post-SRS seizures were associated with prior craniotomy for resection of AVM (P = 0.04), post-treatment hemorrhage (P = 0.02), parietal location (P = 0.05), adverse effect requiring steroids (P0.01), and adverse effect requiring surgery (P0.01).Seizures are a common presentation of brain AVMs and can be treated effectively with SRS. However, seizures can also be a complication of SRS and are associated with post-treatment hemorrhage, edema, and need for future open surgery.

Lobe reconnection is usually thought to play an important role in geospace dynamics only when the Interplanetary Magnetic Field (IMF) is mainly northward. This is because the most common and unambi...

Purpose: Interest and application of stereotactic radiosurgery for multiple brain metastases continue to increase. Various planning systems are available for linear accelerator (linac)–based single-isocenter multiple metastasis radiosurgery. Two of the most advanced systems are BrainLAB Multiple Metastases Elements (MME), a dynamic conformal arc (DCA) approach, and Varian RapidArc (RA), a volumetric modulated arc therapy (VMAT) approach. In this work, we systematically compared plan quality between the 2 techniques. Methods and Materials: Thirty patients with 4 to 10 metastases (217 total; median 7.5; Vmin = 0.014 cm3; Vmax = 17.73 cm3) were planned with both Varian RA and MME at 2 different institutions with extensive experience in each respective technique. All plans had a single isocenter and used Varian linac equipped with high-definition multileaf collimator. RA plans used 2 to 4 noncoplanar VMAT arcs with 10 MV flattening filter-free beam. MME plans used 4 to 9 noncoplanar DCAs and 6 MV flattening filter-free beam, (minimum planning target volume [PTVmin] = 0.49 cm3; PTVmax = 27.32 cm3; PTVmedian = 7.05 cm3). Prescriptions were 14 to 24 Gy in a single fraction. Target coverage goal was 99% of volume receiving prescription dose (D99% ≥ 100%). Plans were evaluated by Radiation Therapy Oncology Group/Paddick conformity index (CI) score, 12 Gy volume (V12Gy), V8Gy, V5Gy, mean brain dose (Dmean), and beam-on time. Results: Conformity was favorable among RA plans (median: MME CIRTOG = 1.38; RA CIRTOG = 1.21; P < .0001). V12Gy and V8Gy were lower for RA plans (median: MME V12 = 23.7 cm3; RA V12 = 19.2 cm3; P = .0001; median: MME V8Gy = 53.6 cm3; RA V8Gy = 44.1 cm3; P = .024). V5Gy was lower for MME plans (median: MME V5Gy = 141.4 cm3; RA V5Gy = 142.8 cm3; P = .009). Mean brain was lower for MME plans (median: MME Dmean = 2.57 Gy; RA Dmean = 2.76 Gy; P < .0001). Conclusions: For linac-based multiple metastasis stereotactic radiosurgery, RapidArc VMAT facilitates favorable conformity and V12Gy/V8Gy volume compared with the MME DCA plan. MME planning facilitates reduced dose spill at levels ≤V5Gy.

Space weather can cause serious disturbances of global navigation satellite systems (GNSS) used for positioning and navigation purposes. This paper describes a new method to forecast space weather disturbances on GNSS at high latitudes, in which we describe the formation and propagation of polar cap patches and predict their arrival at the nightside auroral oval. The space weather prediction model builds on the expanding/contracting polar cap (ECPC) paradigm and total electron content (TEC) observations from the Global Positioning System (GPS) network. The input parameter is satellite observations of the interplanetary magnetic field at the first Lagrange point. To validate our prediction model, we perform a case study in which we compare the results from our prediction model to observations from the GPS TEC data from the MIT's Madrigal database, convection data from Super Dual Auroral radar network, and scintillation data from Svalbard. Our results show that the ECPC paradigm describes the polar cap patch motion well and can be used to predict scintillations of GPS signals at high latitudes.

The PackH2O water backpack carrier was developed to provide safe storage and relieve stress of head-loading during water transport with traditional containers such as buckets and jerry cans. We conducted an evaluation to assess both self-reported and observed use over a 6-month period between November 2014 and May 2015. A total of 866 packs were distributed to 618 households in six communities in rural Haiti, and 431 and 441 households were surveyed at midline and end line, respectively. We performed linear regression to assess change of self-reported use over time. Although 79.3% of respondents reported continued use of the 20-L pack after 6 months, other measures of self-reported use were low, with only 16.8% reporting to have used the pack the last time they collected water and 10.3% preferring the pack over other water collection containers. In addition, only 10.2% of all people collecting water at community sources were observed using packs and 12.0% of all households surveyed had water in the pack at the time of visit. Pack use varied by community and demographics. Although women were targeted during distribution, men preferred the pack and were more commonly observed using it at the community water sources. In conclusion, the use of the PackH2O was not widely adopted in rural Haiti; however, further research is needed to assess the pack acceptance in areas where back-loading is more common and in emergency settings.

The Included Phase Model (IPM) is a mesoscale technique, which describes the morphology of phase-phase interfaces as a parametric surface to reduce computational costs while preserving the important features of phase-field type models. The IPM is extended to include a fluid species (fission gas) occupying vacancies. System evolution is driven by interfacial energy, elasticity of the surrounding matrix, and internal energy of the fluid. The model is extended to multiple grains using a symmetry condition and applied to a network of hexagonal grains. The model is applied to investigate fission gas accommodation and percolation as a function of the distance to a free surface and distribution of high fission density areas corresponding to heterogeneity resulting from the manufacturing processes of mixed oxide fuels.

Brain metastases are a devastating sequela of common primary cancers (e.g., lung, breast, and skin) and have limited effective therapeutic options. Previously, systemic chemotherapy failed to demonstrate significant benefit in patients with brain metastases, but in recent decades, targeted therapies and more recently immune checkpoint inhibitors (ICIs) have yielded promising results in preclinical and clinical studies. Furthermore, there is significant interest in harnessing the immunomodulatory effects of radiotherapy (RT) to synergize with ICIs. Herein, we discuss studies evaluating the impact of RT dose and fractionation on the immune response, early studies supporting the synergistic interaction between RT and ICIs, and ongoing clinical trials assessing the benefit of combination therapy in patients with brain metastases.

Glioblastoma (GBM) is an aggressive primary brain tumor that is associated with a poor prognosis and quality of life. The standard of care has changed minimally over the past two decades and currently consists of surgery followed by radiotherapy (RT), concomitant and adjuvant temozolomide, and tumor treating fields (TTF). Factors such as tumor hypoxia and the presence of glioma stem cells contribute to the radioresistant nature of GBM. In this review, we discuss the current treatment modalities, mechanisms of radioresistance, and studies that have evaluated promising radiosensitizers. Specifically, we highlight small molecules and immunotherapy agents that have been studied in conjunction with RT in clinical trials. Recent preclinical studies involving GBM radiosensitizers are also discussed.

Relative transcript abundance has proven to be a valuable tool for understanding the function of genes in biological systems. For the differential analysis of transcript abundance using RNA sequencing data, the negative binomial model is by far the most frequently adopted. However, common methods that are based on a negative binomial model are not robust to extreme outliers, which we found to be abundant in public datasets. So far, no rigorous and probabilistic methods for detection of outliers have been developed for RNA sequencing data, leaving the identification mostly to visual inspection. Recent advances in Bayesian computation allow large-scale comparison of observed data against its theoretical distribution given in a statistical model. Here we propose ppcseq, a key quality-control tool for identifying transcripts that include outlier data points in differential expression analysis, which do not follow a negative binomial distribution. Applying ppcseq to analyse several publicly available datasets using popular tools, we show that from 3 to 10 percent of differentially abundant transcripts across algorithms and datasets had statistics inflated by the presence of outliers.

Predicted climate-induced changes in the Great Lakes include increased variability in water levels, which may shift periphyton habitat. Our goal was to determine the impacts of water level changes in Lake Superior on the periphyton community assemblages in the Keweenaw Peninsula with different surface geology. At three sites, we identified periphyton assemblages as a function of depth, determined surface area of periphyton habitat using high resolution bathymetry, and estimated the impact of water level changes in Lake Superior on periphyton habitat. Our results suggest that substrate geology influences periphyton community assemblages in the Keweenaw Peninsula. Using predicted changes in water levels, we found that a decrease in levels of 0.63 m resulted in a loss of available surface area for periphyton habitat by 600 to 3000 m2 per 100 m of shoreline with slopes ranging 2 to 9&deg, If water levels rise, the surface area of substrate will increase by 150 to 370 m2 per 100 m of shoreline, as the slopes above the lake levels are steeper (8&ndash, 20&deg, ). Since periphyton communities vary per site, changes in the surface area of the substrate will likely result in a shift in species composition, which could alter the structure of aquatic food webs and ecological processes.

We analyze the spatial variation in the response of the surface geomagnetic field (or the equivalent ionospheric current) to variations in the solar wind. Specifically, we regress a reanalysis of surface external and induced magnetic field (SEIMF) variations onto measurements of the solar wind. The regression is performed in monthly sets, independently for 559 regularly spaced locations covering the entire northern polar region above 50° magnetic latitude. At each location, we find the lag applied to the solar wind data that maximizes the correlation with the SEIMF. The resulting spatial maps of these independent lags and regression coefficients provide a model of the localized SEIMF response to variations in the solar wind, which we call “Spatial Information from Distributed Exogenous Regression.” We find that the lag and regression coefficients vary systematically with ionospheric region, season, and solar wind driver. In the polar cap region the SEIMF is best described by the B y component of the interplanetary magnetic field (50–75% of total variance explained) at a lag ∼20–25 min. Conversely, in the auroral zone the SEIMF is best described by the solar wind ϵ function (60–80% of total variance explained), with a lag that varies with season and magnetic local time (MLT), from ∼15–20 min for dayside and afternoon MLT (except in Oct–Dec) to typically 30–40 min for nightside and morning MLT and even longer (60–65 min) around midnight MLT. publishedVersion

The high frequency radars in the Super Dual Auroral Radar Network (SuperDARN) estimate the elevation angles of returned backscatter using interferometric techniques. These elevation angles allow the ground range to the scattering point to be estimated, which is crucial for the accurate geolocation of ionospheric measurements. For elevation angles to be accurately estimated, it is important to calibrate the interferometer measurements by determining the difference in the signal time delays caused by the difference in the electrical path lengths from the main array and the interferometer array to the point at which the signals are correlated. This time delay is known as t diff . Several methods have been proposed to estimate t diff using historical observations; these methods are summarised in this paper. Comparisons of the t diff estimates from the different calibration methods are presented and sources of uncertainty discussed. The effect of errors in the estimated t diff value on the accuracy of geolocation is evaluated and discussed. The paper concludes with a series of recommendations for both scientific SuperDARN data users and SuperDARN radar operators.

Engineered environmental health interventions and services in low-income and resource-limited settings-such as water supply and treatment, sanitation, and cleaner household energy services-have had a less than expected record of sustainability and have sometimes not delivered on their potential to improve health. These interventions require both effectively functioning technologies as well as supporting financial, political, and human resource systems, and may depend on user behaviors as well as professionalized service delivery to reduce harmful exposures. In this perspective, we propose that the application of smarter, more actionable monitoring and decision support systems and aligned financial incentives can enhance accountability between donors, implementers, service providers, governments, and the people who are the intended beneficiaries of development programming. Made possible in part by new measurement techniques, including emerging sensor technologies, rapid impact evaluation, citizen science, and performance-based contracting, such systems have the potential to propel the development of solutions that can work over the long-term, allowing the benefits of environmental health improvements to be sustained in settings where they are most critical by improving trust and mutual accountability among stakeholders.

Rural isolation can limit access to basic services and income-generating opportunities. Among some communities, rainfall induced flooding can cause increased uncertainty where first-mile transportation infrastructure is limited. In Rwanda, this challenge is apparent, where 90% of the population below the poverty line live in rural areas that are typically mountainous with frequent flooding - events that may be increasing in frequency and severity as the climate changes. To reduce these transportation barriers, the non-profit organization Bridges to Prosperity (B2P) plans to construct hundreds of trailbridges in Rwanda between 2018 and 2023. This scale of rural infrastructure services presents an opportunity for experimental investigation of the effects of these new trailbridges on economic, health, agricultural and education outcomes in rural communities. In this paper, we present a cohort study evaluating the potential community benefits of rural trailbridges - including economic, health and social outcomes for Rwandan communities experiencing environmental change. We examined households living near 12 trailbridge sites and 12 comparison sites over February 2019–March 2020. We found that labor market income increased by 25% attributable to the trailbridges. We did not observe any significant effects on agricultural income, education or health outcomes, however given the small sample and short duration of this study we anticipate observing additional outcomes within the recently started 200 site, 4 year trial.

To address the complex challenge of sustaining basic water and sanitation services in low income settings, international organizations and local and national government entities are beginning to design and implement interventions explicitly aimed at addressing system weaknesses. Often referred to as &ldquo, systems approaches,&rdquo, these interventions seek to understand, engage with, and positively influence the network of actors and the interacting factors that deliver services. As WASH sector assistance and support activities shift toward systems approaches, many associated intermediate results and desired outcomes become less quantifiable than those of more traditional WASH activities. This paper reviews systems approaches, evaluation methodologies, and several applications in East Africa, at varying geographic scales. Early findings from the application of outcome mapping and system-wide assessments within the USAID-funded Sustainable WASH Systems Learning Partnership (SWS) indicate the importance of including both within an overall monitoring approach to support systems strengthening of water and sanitation services. The views and opinions expressed in this paper are those of the author(s) and not necessarily the views and opinions of the United States Agency for International Development, or the U.S. Government.

Low-cost, field-deployable, near-time methods for assessing water quality are not available when and where waterborne infection risks are greatest. We describe the development and testing of a novel device for the measurement of tryptophan-like fluorescence (TLF), making use of recent advances in deep-ultraviolet light emitting diodes (UV-LEDs) and sensitive semiconductor photodiodes and photomultipliers. TLF is an emerging indicator of water quality that is associated with members of the coliform group of bacteria and therefore potential fecal contamination. Following the demonstration of close correlation between TLF and E. coli in model waters and proof of principle with sensitivity of 4 CFU/mL for E. coli, we further developed a two-LED flow-through configuration capable of detecting TLF levels corresponding to &ldquo, high risk&rdquo, fecal contamination levels (&gt, 10 CFU/100 mL). Findings to date suggest that this device represents a scalable solution for remote monitoring of drinking water supplies to identify high-risk drinking water in near-time. Such information can be immediately actionable to reduce risks.

Relative transcript abundance has proven to be a valuable tool for inferring the phenotype of biological systems from genetic material. Several methods for the analysis of differential transcript abundance have been developed, and some of the most popular are based on negative binomial models. Although most genes are fitted reasonably well by the negative binomial distribution, the presence of outlier observations that do not fit such models can lead to artifactual identification of significant changes in transcription. Identifying those transcripts for the correct interpretation of results is extremely important. A robust and automated tool for detecting sample/transcript pairs that do not fit a negative binomial regression model is currently lacking. Here we propose ppcseq, a robust statistical framework that models hierarchically sample- and gene-wise features such as sequencing depth bias, the association between mean transcript abundance and its over-dispersion, and provides a theoretical transcript abundance distribution, on which the observed transcript abundance can be tested for outliers. We show using a publicly available data set where nearly 10% of differentially abundant transcripts had fold change inflated by the presence of outliers. This method has broad utility in filtering artifactual results of differential transcript abundance analyses based on a negative binomial framework.