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1. Introduction Burst Intensification by Singularity Emitting Radiation (BISER) [1] is the emission of coherent traveling waves by multi-stream flow singularities. Such singularities can be produced in relativistic plasma by high-power lasers, resulting in very bright coherent x-ray emission [2],[3]. 2. Experimental We have recently performed an experiment on BISER coherent x-ray generation with the Astra Laser at the CLF RAL, UK. We extensively optimized the experimental conditions, namely the plasma density and profile, and laser spot [4] and pulse, making use of substantial beam time. This resulted in a ~2 orders of magnitude higher BISER brightness compared to earlier experiments with 10 TW lasers. 3. Results In this presentation we discuss results from two soft x-ray spectrographs: a three-channel flat field spectrograph [5] in the forward direction (channels at −0.6, 0, and 0.8°) operating in the 17-34 nm range and a normal-incidence imaging spectrograph [6] in a 10° off-axis direction operating in the 12.4-20 nm range. Under optimum conditions, both spectrographs showed μJ and higher BISER pulse energies per shot in the corresponding spectral ranges and within their acceptance angles. This implies multi-100 μJ BISER pulses in the entire spectral range and within the full angular width. Acknowledgement We acknowledge support from the Astra Laser Group and the CLF Target Fab, Mechanical, and Electrical. Financial support: JSPS Kakenhi JP 19KK0355 and 19H00669, CLF, Russian Science Foundation (20-62-46050), IAP RAS, ELI-Beamlines, MŠMT by the project "Advanced Research Using High Intensity Laser Produced Photons and Particles" (CZ.02.1.01/0.0/0.0/16_019/0000789), High Field Initiative (CZ.02.1.01/0.0/0.0/15_003/0000449) from the European Regional Development Fund, and the QST Director Fund 創成的研究 #20. References [1]A. S. Pirozhkov, T. Zh. Esirkepov et al., "Burst intensification by singularity emitting radiation in multi-stream flows," Sci. Rep. 7, 17968 (2017). [2]A. S. Pirozhkov, et al. "Soft-X-Ray Harmonic Comb from Relativistic Electron Spikes" PRL 108, 135004 (2012). [3]A. S. Pirozhkov, et al., "High order harmonics from relativistic electron spikes" NJP 16, 093003 (2014). [4]A. S. Pirozhkov, et al. "Laser Requirements for High-Order Harmonic Generation by Relativistic Plasma Singularities," Quantum Beam Sci. 2, 7 (2018). [5]D. Neely, et al., "A multi-channel soft X-ray flat-field spectrometer," AIP Conf. Proc. 426, 479 (1998). [6]A. N. Shatokhin, et al., "High-resolution stigmatic spectrograph for a wavelength range of 12.5-30 nm," Opt. Express 26, 19009 (2018)., OPIC-2022 (ALPS-2022)

Burst Intensification by Singularity Emitting Radiation (BISER) [1] is the phenomenon of extremely bright coherent wave emission (constructive interference, N^2 effect) by singularities of multi-stream flows. High-power femtosecond lasers can produce such flows and corresponding relativistic plasma singularities in underdense plasma; these singularities emit very bright coherent x-rays [2]-[3]. We have recently performed an experiment on BISER coherent x-ray generation with the Astra Laser in the CLF RAL, UK. We observed BISER coherent soft x-rays with two spectrographs: a three-channel flat field spectrograph [4] in the forward direction (channels at -0.6, 0, and 0.8°) operating in the 17-34 nm range and a normal-incidence imaging spectrograph [5] in a 10° off-axis direction operating in the 12.4-20 nm range. Both spectrographs, in addition, provided data on the angular distribution of the BISER radiation. We took advantage of an extensive experiment term and long daily laser operation hours to optimize the laser (in particular, focal spot, which is a necessary prerequisite for BISER [6], and pulse width) and the experimental conditions (in particular, the density profile). These resulted in ~2 orders of magnitude enhancement in BISER photon number, providing >10^11 photons and >μJ energies per pulse in each channel at 7 TW laser power, the result which could previously be obtained at >100 TW laser power only. We acknowledge support from the Astra Laser Group and the CLF Target Fab, Mechanical, and Electrical. Financial support: JSPS Kakenhi JP 19KK0355 and 19H00669, CLF, Russian Science Foundation (20-62-46050), IAP RAS, ELI-Beamlines, the Ministry of Education, Youth and Sports of the Czech Republic by the project "Advanced Research Using High Intensity Laser Produced Photons and Particles" (CZ.02.1.01/0.0/0.0/16_019/0000789), and the QST Director Fund 創成的研究 #20. [1] A. Pirozhkov, T. Esirkepov et al., "Burst intensification by singularity emitting radiation in multi-stream flows," Sci. Rep. 7, 17968 (2017). [2] A. S. Pirozhkov et al. "Soft-X-Ray Harmonic Comb from Relativistic Electron Spikes" PRL 108 135004 (2012) [3] A. S. Pirozhkov et al., "High order harmonics from relativistic electron spikes" New J. Phys. 16, 093003 (2014). [4] D. Neely et al., "A multi-channel soft X-ray flat-field spectrometer," AIP Conf. Proc. 426, 479 (1998). [5] A. Shatokhin et al., "High-resolution stigmatic spectrograph for a wavelength range of 12.5-30 nm," Opt. Express 26 19009 (2018). [6] A. S. Pirozhkov, et al. "Laser Requirements for High-Order Harmonic Generation by Relativistic Plasma Singularities," Quantum Beam Sci. 2, 7 (2018)., Annual meeting of the JSAP

We have recently performed an experiment on BISER with the Astra Laser in the CLF RAL. Here we present some of the experiment highlights., 2021 Christmas Meeting of the High Powered Laser Science Community

Purpose: Rehabilitation professionals support people with traumatic brain injury (TBI) to return to meaningful participation in life and society - which now includes the use of social media. However, the role of health professionals in supporting the use of social media by adults with TBI is not yet known. This study aimed to investigate the experiences and views of rehabilitation professionals on the use of social media by people with TBI during rehabilitation.Method: Two focus groups were conducted and analysed qualitatively for content themes.Results: Eleven rehabilitation professionals, including allied health, recreational therapy, and service management, took part in this study. Participants identified potential benefits to people with TBI using social media, including reduced social isolation. However, they expressed concerns about social media risks relating to the vulnerability, exploitation, and reputation management for people with TBI. Rehabilitation professionals viewed their role as being to protect people from these risks of harm, either through imposing restrictions on social media use or responding to problems after these occurred.Conclusion: A knowledge translation approach might help guide and support rehabilitation professionals in enabling adults with TBI to safely access and experience the benefits of meaningful engagement in social media during rehabilitation.Implications for rehabilitationRehabilitation professionals can start addressing social media use during collaborative goal setting, in order to support people with traumatic brain injury to use social media successfully during rehabilitation and beyond. To do this, professionals can inquire as to the person's previous social media use and identify priority areas for the person for short- and long-term goals.Rehabilitation targeting social media use should include instruction for participation in social media platforms, providing education and feedback that is positive and constructive, as well as risk management education.Policy and guidance is needed for rehabilitation professionals to more actively support people with traumatic brain injury to access social media for improved participation and inclusion in online communities.Addressing social media goals in rehabilitation should be informed by existing successful traumatic brain injury rehabilitation approaches (e.g., functional rehabilitation) and adopting strategies used in rehabilitation supporting other higher risk goals (e.g., return to driving).

Purpose The aim of the study was to investigate the experiences of people with traumatic brain injury (TBI) and rehabilitation professionals in use of social media after TBI. Design Metasynthesis of a multilevel mixed-methods research design was used in the study. Method A qualitative metasynthesis of (a) evidence in the literature regarding the use of communication technologies and social media after TBI, (b) Twitter data and network analysis, (c) interviews with people with TBI (n = 13), (d) focus groups with TBI rehabilitation professionals (n = 11), and (e) a review of current guidance on safe use of social media was conducted. Results People with TBI adopt a trial-and-error approach to using social media. Their meaningful use and a sense of connection enable them to develop social media mastery. TBI rehabilitation professionals' concerns regarding potential risks associated with using social media might lead them to restrict social media use during rehabilitation. Conclusions Access to proactive training in social media use and a supportive network of rehabilitation professionals, family, and friends can enable people with TBI to develop social media mastery through working collaboratively on social media goals. This metasynthesis of research culminates in an evidence-based protocol for assessing and supporting a person with TBI's social media goals to guide clinical practice and future research in the field.

© Australasian Society for the Study of Brain Impairment 2019. Aim:of this study was to examine the Twitter experiences and networks of six adults with cognitive-communication disability after a traumatic brain injury (TBI).Method:Using mixed methods, the study integrated: (a) quantitative analysis of Twitter networks using computational and manual coding of tweets; and (b) narrative analysis of in-depth interviews.Results:Diverse experiences were evident, with two experienced and four novice users of the platform. However, all reported feeling connected and included, and identified both positive and negative experiences in their use of Twitter. Developing a supportive network facilitated higher frequency of tweets and increased feelings of enjoyment and connectedness. All expressed a desire to continue using or learning to use Twitter but novices lacked support from rehabilitation professionals or experienced Twitter users, and relied instead on a "trial and error" approach.Conclusion:Proactive integration of Twitter use during rehabilitation after TBI is warranted to support safe, enjoyable, and meaningful use.

Large recruitment plates measuring 1 × 1 m were deployed over an 18-month period from September 2013 to March 2015 for the purpose of documenting recruitment and colonization processes of marine invertebrate species at Woods Hole, Massachusetts. Each side of two plates was subdivided into 16 subareas (25 × 25 cm), and an observational strategy was developed whereby, at approximately two-week intervals, a different subarea was cleaned. Using this approach, we were able to photographically document species recruitment and growth interactions. Water temperature records from the site show that steady warming and cooling between 3 and 20° C changed at a mean rate of 0.2 ° C d -1 . However, temperature changes during the coolest and warmest parts of the temperature cycle were highly variable. In 2014, between the first and last occurrence of 0° C, temperatures were ≤0° C 15 percent of the time, but in 2015 temperatures were ≤0° C 93 percent of the time. In 2014, between the first and last occurrence of 21° C, temperatures were ≥21° C 88 percent of the time, and this warm period correlated with the disappearance of the hydroid Ectopleura crocea, the solitary tunicates Ascidiella aspersa and Ciona intestinalis, and the 2013 generation of Botrylloides violaceus. In Woods Hole, large plates provided enough space to accommodate both fast- and slow-colonizing species, resulting in the establishment of a diverse assemblage that was observed over a long time period. The most successful colonizing species had relatively long reproductive and recruitment periods, grew rapidly, repelled settlement onto their surfaces by larvae of any species, defended themselves against overgrowth by any species, overwintered, and lived a long time. Of the three dominant species observed in this study, the colonial tunicates Didemnum vexillum and Botrylloides violaceus had these qualities; the encrusting colonial bryozoan Schizoporella unicornis had all but one, it grew more slowly than the others. Barnacles constituted the only biological substrate that was effectively colonized by other species, both by larval recruitment and overgrowth. In Woods Hole, after a substrate had become fully colonized, there was very little opportunity for new recruitment or colony growth until new substrate opened after the death of colonies and individuals and the disappearance of biogenic structures such as amphipod tubes. An understanding of colonization processes utilized by invasive species allows prediction of their potential effects on ecosystems in areas where they are not yet present.

© 2017 Taylor & Francis Group, LLC. Objective: The aims of this study were to: (a) determine how Twitter is used by people with traumatic brain injury (TBI) and TBI organisations, (b) analyse the Twitter networks and content of tweets tagged with TBI-related hashtags, and (c) identify any challenges people with TBI encounter in using Twitter. Research Design: Mixed methods in a Twitter hashtag study. Methods: Mixed methods in a Twitter hashtag study. Tweets tagged with TBI-related hashtags were harvested from the Twitter website over a one-month period in 2016 and analysed qualitatively and quantitatively. Results: The sample of 29,199 tweets included tweets sent by 893 @users, 219 of whom had a brain injury. Twitter was used to: (a) discuss health issues, (b) raise awareness of TBI, (c) talk about life after TBI, (d) talk about sport and concussion, and (e) communicate inspirational messages. Conclusions: Twitter is an important platform for research and knowledge translation on TBI, and for hearing the voices of people with TBI as they express their personal views and stories of living with TBI and become more visible and influential in Twitter communities. TBI clinicians could use these narratives of people with TBI in Twitter to develop more effective and personally meaningful rehabilitation goals.