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Abstract In recent years, significant progress has been made in laser wakefield acceleration (LWFA), both regarding the increase in electron energy, charge and stability as well as the reduction of bandwidth of electron bunches. Simultaneous optimization of these parameters is, however, still the subject of an ongoing effort in the community to reach sufficient beam quality for next generation’s compact accelerators. In this report, we show the design of slit-shaped gas nozzles providing centimeter-long supersonic gas jets that can be used as targets for the acceleration of electrons to the GeV regime. In LWFA experiments at the Centre for Advanced Laser Applications, we show that electron bunches are accelerated to $${1}\text {GeV}$$ 1 GeV using these nozzles. The electron bunches were injected into the laser wakefield via a laser-machined density down-ramp using hydrodynamic optical-field-ionization and subsequent plasma expansion on a ns-timescale. This injection method provides highly controllable quasi-monoenergetic electron beams with high charge around $${100}\text {pC}$$ 100 pC , low divergence of $${0.5}\text {mrad}$$ 0.5 mrad , and a relatively small energy spread of around $${10}\%$$ 10 % at $${1}\text {GeV}$$ 1 GeV . In contrast to capillaries and gas cells, the scheme allows full plasma access for injection, probing or guiding in order to further improve the energy and quality of LWFA beams.

Abstract Background Standardized order sets are a means of increasing adherence to clinical practice guidelines and improving the quality of patient care. Implementation of novel quality improvement initiatives like order sets can be challenging. Before the COVID-19 pandemic, we conducted a formative evaluation to understand healthcare providers’ perspectives on implementing clinical changes and the individual, collective and organizational contextual factors that might impact implementation at eight hospital sites in Alberta, Canada. Methods We utilized concepts from the Consolidated Framework for Implementation Research (CFIR) and Normalisation Process Theory (NPT) to understand the context, past implementation experiences, and perceptions of the cirrhosis order set. Eight focus groups were held with healthcare professionals caring for patients with cirrhosis. Data were coded deductively using relevant constructs of NPT and CFIR. A total of 54 healthcare professionals, including physicians, nurses, nurse practitioners, social workers and pharmacists and a physiotherapist, participated in the focus groups. Results Key findings revealed that participants recognized the value of the cirrhosis order set and its potential to improve the quality of care. Participants highlighted potential implementation challenges, including multiple competing quality improvement initiatives, feelings of burnout, lack of communication between healthcare provider groups, and a lack of dedicated resources to support implementation. Conclusions Implementing a complex improvement initiative across clinician groups and acute care sites presents challenges. This work yielded insights into the significant influence of past implementation of similar interventions and highlighted the importance of communication between clinician groups and resources to support implementation. However, by using multiple theoretical lenses to illuminate what and how contextual and social processes will influence uptake, we can better anticipate challenges during the implementation process.

ABSTRACT The emergence and explosive spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019 highlighted the need to rapidly develop curated biobanks to inform the etiology, diagnosis, and treatment options for global outbreaks of communicable diseases. Recently, we undertook efforts to develop a repository of biospecimens from individuals aged 12 and older who were to be vaccinated against coronavirus disease 19 (COVID-19) with vaccines developed with support from the United States Government. We planned to establish 40 or more clinical study sites in at least six countries to collect biospecimens from 1,000 individuals, 75% of whom were to be SARS-CoV-2 naive at the time of enrollment. Specimens would be used to (i) ensure quality control of future diagnostic tests, (ii) understand immune responses to multiple COVID-19 vaccines, and (iii) provide reference reagents for the development of new drugs, biologics, and vaccines. Biospecimens included serum, plasma, whole blood, and nasal secretions. Large-volume collections of peripheral blood mononuclear cells (PBMCs) and defibrinated plasma were also planned for a subset of subjects. Participant sampling was planned at intervals prior to and following vaccination over a 1-year period. Here, we describe the selection of clinical sites for specimen collection and processing, standard operating procedure (SOP) development, design of a training program for tracking specimen quality, and specimen transport to a repository for interim storage. This approach allowed us to enroll our first participants within 21 weeks from the study’s initiation. Lessons learned from this experience should benefit the development of biobanks in response to future global epidemics. IMPORTANCE The ability to rapidly create a biobank of high-quality specimens in response to emergent infectious diseases is critical to allow for the development of prevention and treatment, as well as to effectively monitor the spread of the disease. In this paper, we report on a novel approach to getting global clinical sites up and running within a short time frame and to monitor the quality of specimens collected to ensure their value in future research efforts. Our results have important implications for the monitoring of the quality of biospecimens collected and to design effective interventions to address shortcomings, where needed.

The DIII-D tokamak has elucidated crucial physics and developed projectable solutions for ITER and fusion power plants in the key areas of core performance, boundary heat and particle transport, and integrated scenario operation, with closing the core-edge integration knowledge gap being the overarching mission. New experimental validation of high-fidelity, multi-channel, non-linear gyrokinetic turbulent transport models for ITER provides strong confidence it will achieve Q ⩾ 10 operation. Experiments identify options for easing H-mode access in hydrogen, and give new insight into the isotopic dependence of transport and confinement. Analysis of 2,1 islands in unoptimized low-torque IBS demonstration discharges suggests their onset time occurs randomly in the constant β phase, most often triggered by non-linear 3-wave coupling, thus identifying an NTM seeding mechanism to avoid. Pure deuterium SPI for disruption mitigation is shown to provide favorable slow cooling, but poor core assimilation, suggesting paths for improved SPI on ITER. At the boundary, measured neutral density and ionization source fluxes are strongly poloidally asymmetric, implying a 2D treatment is needed to model pedestal fuelling. Detailed measurements of pedestal and SOL quantities and impurity charge state radiation in detached divertors has validated edge fluid modelling and new self-consistent ‘pedestal-to-divertor’ integrated modeling that can be used to optimize reactors. New feedback adaptive ELM control minimizes confinement reduction, and RMP ELM suppression with sustained high core performance was obtained for the first time with the outer strike point in a W-coated, compact and unpumped small-angle slot divertor. Advances have been made in integrated operational scenarios for ITER and power plants. Wide pedestal intrinsically ELM-free QH-modes are produced with more reactor-relevant conditions, Low torque IBS with W-equivalent radiators can exhibit predator-prey oscillations in T _e and radiation which need control. High- β _P scenarios with q _min > 2, q _95 –7.9, β _N > 4, β _T –3.3% and H _98y2 > 1.5 are sustained with high density ( $\bar n$ = 7E19 m ^−3 , f _G –1) for 6 τ _E , improving confidence in steady-state tokamak reactors. Diverted NT plasmas achieve high core performance with a non-ELMing edge, offering a possible highly attractive core-edge integration solution for reactors.

Abstract Background Provision of virtual health care (VHC) home monitoring for patients who are experiencing mild to moderate COVID-19 illness is emerging as a central strategy for reducing pressure on acute health systems. Understanding the enablers and challenges in implementation and delivery of these programs is important for future implementation and re-design. The aim of this study was to explore the perspectives of staff involved with the implementation and delivery, and the experience of patients managed by, a VHC monitoring service in Melbourne, Australia during the COVID-19 pandemic. Methods A descriptive qualitative approach informed by naturalist inquiry was used. Staff interviews were analysed using the Consolidated Framework for Implementation Research (CFIR). Patient experience was captured using a survey and descriptive statistics were used to describe categorical responses while content analysis was used to analyse free text responses as they related to the CFIR. Finally, data from the interviews and patient experience were triangulated to see if patient experience validated data from staff interviews. Results All 15 staff were interviewed, and 271 patients were surveyed (42%). A total of four final overarching themes emerged: service implementation enablers, service delivery benefits for patients, fragmentation of care, and workforce strengths. 19 subthemes aligned with 18 CFIR constructs from staff and patient data. Conclusion Rapid implementation was enabled through shared resources, dividing implementation tasks between senior personnel, engaging furloughed healthcare staff in design and delivery, and having a flexible approach that allowed for ongoing improvements. Benefits for patients included early identification of COVID-19 deterioration, as well as provision of accurate and trustworthy information to isolate safely at home. The main challenges were the multiple agencies involved in patient monitoring, which may be addressed in the future by attributing responsibility for monitoring to a single agency.

Parkinson's disease (PD) results in progressively worsening gait and balance dysfunction that can be measured using computerized devices. We utilized the longitudinal database of the Parkinson's Disease Biomarker Program to determine if baseline gait and balance measures predict future rates of symptom progression. We included 230, 222, 164, and 177 PD subjects with 6, 12, 18, and 24 months of follow-up, respectively, and we defined progression as worsening of the following clinical parameters: MDS-UPDRS total score, Montreal Cognitive Assessment, PDQ-39 mobility subscale, levodopa equivalent daily dose, Schwab and England score, and global composite outcome. We developed ridge regression models to independently estimate how each gait or balance measure, or combination of measures, predicted progression. The accuracy of each ridge regression model was calculated by cross-validation in which 90% of the data were used to estimate the ridge regression model which was then tested on the 10% of data left out. While the models modestly predicted change in outcomes at the 6-month follow-up visit (accuracy in the range of 66–71%) there was no change in the outcome variables during this short follow-up (median change in MDS-UPDRS total score = 0 and change in LEDD = 0). At follow-up periods of 12, 18, and 24 months, the models failed to predict change (accuracy in the held-out sets ranged from 42 to 60%). We conclude that this set of computerized gait and balance measures performed at baseline is unlikely to help predict future disease progression in PD. Research scientists must continue to search for progression predictors to enhance the performance of disease modifying clinical trials.

This study explored relationships between hope, self-efficacy, and professional identity among a group of undergraduate engineering students at a western institution of higher education in the United States (US) over the span of an academic semester. We conducted a mixed-methods study with undergraduate engineering students to measure aspects of hope, and self-efficacy. Furthermore, we investigated how they perceived their own professional identity in terms of what it means to be an engineer and engage in the profession. Participants reported high levels of hope at mid- and end-of-semester. Those pursuing degrees requiring professional licensure reported higher levels of willpower compared to students pursuing non-licensure degrees. Students experienced increased self-efficacy towards engineering skills and processes over time. Participants' perceptions of engineering professional identity remained consistent over the semester. Their sense of engineering work and goal orientation fell primarily into one of three archetypes: Pragmatic, Creative, and Altruistic.

Small unmanned aircraft (SUA) have the potential to be used as platforms for the measurement of atmospheric particulates. The use of an SUA platform for these measurements provides benefits such as high manoeuvrability, reusability, and low cost when compared with traditional techniques. However, the complex aerodynamics of an SUA – particularly for multi-rotor airframes – pose difficulties for accurate and representative sampling of particulates. The use of a miniaturised, lightweight optical particle instrument also presents reliability problems since most optical components in a lightweight system (for example laser diodes, plastic optics, and photodiodes) are less stable than their larger, heavier, and more expensive equivalents (temperature-regulated lasers, glass optics, and photomultiplier tubes). The work presented here relies on computational fluid dynamics with Lagrangian particle tracking (CFD–LPT) simulations to influence the design of a bespoke meteorological sampling system: the UH-AeroSAM. This consists of a custom-built airframe, designed to reduce sampling artefacts due to the propellers, and a purpose-built open-path optical particle counter (OPC) – the Ruggedised Cloud and Aerosol Sounding System (RCASS). OPC size distribution measurements from the UH-AeroSAM are compared with the cloud, aerosol, and precipitation spectrometer (CAPS) for measurements of stratus clouds during the Pallas Cloud Experiment (PaCE) in 2019. Good agreement is demonstrated between the two instruments. The integrated dN∕dlog (Dp) is shown to have a coefficient of determination of 0.8 and a regression slope of 0.9 when plotted 1:1.

Abstract Food‐energy‐water (FEW) systems are increasingly vulnerable to natural hazards and climate change risks, yet humans depend on these systems for their daily needs, wellbeing, and survival. We investigated how adaptations related to FEW vulnerabilities are occurring and what the global community can learn about the interactions across these adaptations. We conducted a global analysis of a data set derived from scientific literature to present the first large scale assessment (n = 1,204) of evidence‐based FEW‐related climate adaptations. We found that the most frequently reported adaptations to FEW vulnerabilities by continent occurred in Africa (n = 495) and Asia (n = 492). Adaptations targeting food security were more robustly documented than those relevant to water and energy security, suggesting a greater global demand to address food security. Determining statistically significant associations, we found a network of connections between variables characterizing FEW‐related adaptations and showed interconnectedness between a variety of natural hazards, exposures, sectors, actors, cross‐cutting topics and geographic locations. Connectivity was found between the vulnerabilities food security, water, community sustainability, and response to sea level rise across cities, settlements, and key infrastructure sectors. Additionally, generalized linear regression models revealed potential synergies and tradeoffs among FEW adaptations, such as a necessity to synergistically adapt systems to protect food and water security and tradeoffs when simultaneously addressing exposures of consumption and production vs. poverty. Results from qualitative thematic coding showcased that adaptations documented as targeting multiple exposures are still limited in considering interconnectivity of systems and applying a nexus approach in their responses. These results suggest that adopting a nexus approach to future FEW‐related adaptations can have profound benefits in the management of scarce resources and with financial constraints.

We present experimental results on a plasma wakefield accelerator (PWFA) driven by high-current electron beams from a laser wakefield accelerator (LWFA). In this staged setup stable and high-quality (low-divergence and low energy spread) electron beams are generated at an optically generated hydrodynamic shock in the PWFA. The energy stability of the beams produced by that arrangement in the PWFA stage is comparable to both single-stage laser accelerators and plasma wakefield accelerators driven by conventional accelerators. Simulations support that the intrinsic insensitivity of PWFAs to driver energy fluctuations can be exploited to overcome stability limitations of state-of-the-art laser wakefield accelerators when adding a PWFA stage. Furthermore, we demonstrate the generation of electron bunches with energy spread and divergence superior to single-stage LWFAs, resulting in bunches with dense phase space and an angular-spectral charge density beyond the initial drive beam parameters. These results unambiguously show that staged LWFA-PWFA can help to tailor the electron-beam quality for certain applications and to reduce the influence of fluctuating laser drivers on the electron-beam stability. This encourages further development of this new class of staged wakefield acceleration as a viable scheme toward compact, high-quality electron beam sources.

The halo ratio (HR) is a quantitative measure characterizing the occurrence of the 22∘ halo peak associated with cirrus. We propose to obtain it from an approximation to the scattering phase function (SPF) derived from all-sky imaging. Ground-based fisheye cameras are used to retrieve the SPF by implementing the necessary image transformations and corrections. These consist of geometric camera characterization by utilizing positions of known stars in a camera image, transforming the images from the zenith-centred to the light-source-centred system of coordinates and correcting for the air mass and for vignetting, the latter using independent measurements from a sun photometer. The SPF is then determined by averaging the image brightness over the azimuth angle and the HR by calculating the ratio of the SPF at two scattering angles in the vicinity of the 22∘ halo peak. In variance from previous suggestions we select these angles to be 20 and 23∘, on the basis of our observations. HR time series have been obtained under various cloud conditions, including halo cirrus, non-halo cirrus and scattered cumuli. While the HR measured in this way is found to be sensitive to the halo status of cirrus, showing values typically >1 under halo-producing clouds, similar HR values, mostly artefacts associated with bright cloud edges, can also be occasionally observed under scattered cumuli. Given that the HR is an ice cloud characteristic, a separate cirrus detection algorithm is necessary to screen out non-ice clouds before deriving reliable HR statistics. Here we propose utilizing sky brightness temperature from infrared radiometry: both its absolute value and the magnitude of fluctuations obtained through detrended fluctuation analysis. The brightness temperature data permit the detection of cirrus in most but not all instances.

OzFlux is the regional Australian and New Zealand flux tower network that aims to provide a continental-scale national research facility to monitor and assess trends, and improve predictions, of Australia's terrestrial biosphere and climate. This paper describes the evolution, design, and current status of OzFlux as well as provides an overview of data processing. We analyse measurements from all sites within the Australian portion of the OzFlux network and two sites from New Zealand. The response of the Australian biomes to climate was largely consistent with global studies except that Australian systems had a lower ecosystem water-use efficiency. Australian semi-arid/arid ecosystems are important because of their huge extent (70 %) and they have evolved with common moisture limitations. We also found that Australian ecosystems had a similar radiation-use efficiency per unit leaf area compared to global values that indicates a convergence toward a similar biochemical efficiency. The two New Zealand sites represented extremes in productivity for a moist temperate climate zone, with the grazed dairy farm site having the highest GPP of any OzFlux site (2620 gC m−2 yr−1) and the natural raised peat bog site having a very low GPP (820 gC m−2 yr−1). The paper discusses the utility of the flux data and the synergies between flux, remote sensing, and modelling. Lastly, the paper looks ahead at the future direction of the network and concludes that there has been a substantial contribution by OzFlux, and considerable opportunities remain to further advance our understanding of ecosystem response to disturbances, including drought, fire, land-use and land-cover change, land management, and climate change, which are relevant both nationally and internationally. It is suggested that a synergistic approach is required to address all of the spatial, ecological, human, and cultural challenges of managing the delicately balanced ecosystems in Australasia.

Teachers must be able to effectively address the social and academic needs of their students, regardless of cultural differences. It is also critical for teachers to have knowledge of the controlling societal forces affecting their students' lives. Numerous scholars have investigated the overrepresentation of Black males in special education. Understanding students' sociocultural challenges will help teachers develop and implement a culturally responsive curricula for Black students with disabilities. In this qualitative study, focus group interviews were conducted with seven Black adolescent males receiving special education services. Findings revealed primary themes emphasizing the importance of racial reckonings in the classroom and the need for caring and belongingness in the secondary learning environment. The role of the teacher in providing a psychologically safe and culturally responsive classroom is addressed.

El Autismo es un síndrome heterogéneo definido por incapacidad la Interacción Social, lenguaje y comportamientos repetitivos. Existe amplia evidencia que soporta la importancia del componente genético en la etiología del Autismo. Se han identificado muchas regiones cromosómicas y mas recientemente Variaciones en Número de Copias (CNVs) asociadas con estos trastornos. Ocasionalmente se ha llegado a la identificación de genes portadores de mutaciones responsables del trastorno, pero responden por una menor proporción de los casos. Solo algunas de estas asociaciones han sido replicadas, debido a la heterogeneidad genética y fenotípica del trastorno. Objetivos: identificar regiones cromosómicas y genes en ellas de susceptibilidad al Autismo en una muestra de población Colombiana. Metodología: es un estudio de casos y controles, con controles poblacionales y familiares. Los sujetos participantes son casos que cumplen con los criterios diagnósticos del DSM-IV para Autismo o Síndrome de Asperger, de diferentes regiones de Colombia. Los controles son sujetos de población general y padres de los casos. Se genotipificaron SNPs alrededor del genoma con la plataforma Human610Quaddv de Illumina. Se realizo el análisis de asociación, utilizando regresión logística, ajustada por estructuración poblacional criptica. Resultados y conclusiones: se obtuvo una muestra de 98 casos y 285 controles con una tasa de genotipificación del 99.8% para 524.656 SNPs que cumplieron criterios de control de calidad. Para inferir estructura poblacional se utilizo el método de Escalamiento Multidimensional. Se identificó asociación alélica significativa al nivel de 1x10-6 para SNPs en las regiones cromosómicas: 1q44, 3p14-21, 6q14.1, 7q31.1, 8p22, 12p13, 18q23 y 19q13, ajustando por sexo y por la primera dimensión factorial de estructuración poblacional. Algunas de estas regiones han sido asociadas previamente al Autismo y todas portan genes candidatos funcionales para la etiología del trastorno.