scholarly journals Exploring extreme magnetization phenomena in directly-driven imploding cylindrical targets

2021 ◽  
Author(s):  
Chris Walsh ◽  
Ricardo Florido ◽  
Mathieu Bailly-Grandvaux ◽  
Francisco Suzuki-Vidal ◽  
Jeremy P Chittenden ◽  
...  
Keyword(s):  
Significant Proportion ◽  
Magnetized Plasma ◽  
Plasma Parameters ◽  
Core Electron ◽  
Ohmic Dissipation ◽  
Thermally Driven ◽  
Laser Facility ◽  
Omega Laser ◽  
The Impact ◽  
Magnetization Processes

Abstract This paper uses extended-magnetohydrodynamics (MHD) simulations to explore an extreme magnetized plasma regime realisable by cylindrical implosions on the OMEGA laser facility. This regime is characterized by highly compressed magnetic fields (greater than 10kT across the fuel), which contain a significant proportion of the implosion energy and induce large electrical currents in the plasma. Parameters governing the different magnetization processes such as Ohmic dissipation and suppression of instabilities by magnetic tension are presented, allowing for optimization of experiments to study specific phenomena. For instance, a dopant added to the target gas-fill can enhance magnetic flux compression while enabling spectroscopic diagnosis of the imploding core. In particular, the use of Ar K-shell spectroscopy is investigated by performing detailed non-LTE atomic kinetics and radiative transfer calculations on the MHD data. Direct measurement of the core electron density and temperature would be possible, allowing for both the impact of magnetization on the final temperature and thermal pressure to be obtained. By assuming the magnetic field is frozen into the plasma motion, which is shown to be a good approximation for highly magnetized implosions, spectroscopic diagnosis could be used to estimate which magnetization processes are ruling the implosion dynamics; for example, a relation is given for inferring whether thermally-driven or current-driven transport is dominating.

Implication of Medical Treatment for Surgical Strategies in IBD

2019 ◽  
Vol 20 (13) ◽  
pp. 1363-1368
Author(s):  
Krisztina B. Gecse ◽  
Christianne J. Buskens
Keyword(s):  
Nutritional Status ◽  
Medical Treatment ◽  
Significant Proportion ◽  
Timing Of Surgery ◽  
Multidisciplinary Management ◽  
Key Factors ◽  
Surgical Strategies ◽  
Immunosuppressive Medications ◽  
Medical Paradigm ◽  
The Impact

Despite changing medical paradigm, still a significant proportion of patients with IBD require surgery. The patient's general condition, including nutritional status and the use of immunosuppressive medications is of great importance with regard to surgical complications, as well as the choice of optimal surgical strategy. The indication and the timing of surgery are key factors for the multidisciplinary management of IBD patients. The purpose of this review is to provide an overview on the impact of medical treatment on surgical strategies in IBD.

The impact of algorithmic decision-making processes on young people’s well-being (Preprint)

2019 ◽  
Author(s):  
Elvira Perez Vallejos ◽  
Liz Dowthwaite ◽  
Helen Creswich ◽  
Virginia Portillo ◽  
Ansgar Koene ◽  
...  
Keyword(s):  
Young People ◽  
Significant Proportion ◽  
Well Being ◽  
Early Years ◽  
Negative Experiences ◽  
Children And Young People ◽  
Online Platforms ◽  
Internet Users ◽  
Decision Making Processes ◽  
The Impact

BACKGROUND Algorithms rule the online environments and are essential for performing data processing, filtering, personalisation and other tasks. Research has shown that children and young people make up a significant proportion of Internet users, however little attention has been given to their experiences of algorithmically-mediated online platforms, or the impact of them on their mental health and well-being. The algorithms that govern online platforms are often obfuscated by a lack of transparency in their online Terms and Conditions and user agreements. This lack of transparency speaks to the need for protecting the most vulnerable users from potential online harms. OBJECTIVE To capture young people's experiences when being online and perceived impact on their well-being. METHODS In this paper, we draw on qualitative and quantitative data from a total of 260 children and young people who took part in a ‘Youth Jury’ to bring their opinions to the forefront, elicit discussion of their experiences of using online platforms, and perceived psychosocial impact on users. RESULTS The results of the study revealed the young people’s positive as well as negative experiences of using online platforms. Benefits such as being convenient and providing entertainment and personalised search results were identified. However, the data also reveals participants’ concerns for their privacy, safety and trust when online, which can have a significant impact on their well-being. CONCLUSIONS We conclude by making recommendations that online platforms acknowledge and enact on their responsibility to protect the privacy of their young users, recognising the significant developmental milestones that this group experience during these early years, and the impact that technology may have on them. We argue that governments need to incorporate policies that require technologists and others to embed the safeguarding of users’ well-being within the core of the design of Internet products and services to improve the user experiences and psychological well-being of all, but especially those of children and young people. CLINICALTRIAL N/A

The Relationship Between Highly Visual Social Media and Young People’s Mental Health: A Scoping Review (Preprint)

2020 ◽  
Author(s):  
Alanna McCrory
Keyword(s):  
Mental Health ◽  
Social Media ◽  
Young People ◽  
Scoping Review ◽  
Quantitative Methods ◽  
Grey Literature ◽  
Significant Proportion ◽  
Mental Wellbeing ◽  
Published Evidence ◽  
The Impact

UNSTRUCTURED Users of highly visual social media (HVSM), such as Snapchat and Instagram, share their messages through images, rather than relying on words. A significant proportion of people that use these platforms are adolescents. Previous research reveals mixed evidence regarding the impact of online social technologies on this age group’s mental wellbeing, but it is uncertain whether the psychological effects of visual content alone differ from text-driven social media. This scoping review maps existing literature that has published evidence about highly visual social media, specifically its psychological impact on young people. Nine electronic databases and grey literature from 2010 until March 2019 were reviewed for articles describing any aspect of visual social media, young people and their mental health. The screening process retrieved 239 articles. With the application of eligibility criteria, this figure was reduced to 25 articles for analysis. Results indicate a paucity of data that exclusively examines HVSM. The predominance of literature relies on quantitative methods to achieve its objectives. Many findings are inconsistent and lack the richness that qualitative data may provide to explore the reasons for theses mixed findings.

scholarly journals Relative contributions of family history and a polygenic risk score on COPD and related outcomes: COPDGene and ECLIPSE studies

2020 ◽  
Vol 7 (1) ◽  
pp. e000755
Author(s):  
Matthew Moll ◽  
Sharon M. Lutz ◽  
Auyon J. Ghosh ◽  
Phuwanat Sakornsakolpat ◽  
Craig P. Hersh ◽  
...  
Keyword(s):  
Family History ◽  
Risk Score ◽  
Characteristic Curve ◽  
Significant Proportion ◽  
Chronic Obstructive ◽  
Polygenic Risk Score ◽  
Positive Interaction ◽  
Polygenic Risk ◽  
Mediation Analyses ◽  
The Impact

IntroductionFamily history is a risk factor for chronic obstructive pulmonary disease (COPD). We previously developed a COPD risk score from genome-wide genetic markers (Polygenic Risk Score, PRS). Whether the PRS and family history provide complementary or redundant information for predicting COPD and related outcomes is unknown.MethodsWe assessed the predictive capacity of family history and PRS on COPD and COPD-related outcomes in non-Hispanic white (NHW) and African American (AA) subjects from COPDGene and ECLIPSE studies. We also performed interaction and mediation analyses.ResultsIn COPDGene, family history and PRS were significantly associated with COPD in a single model (PFamHx <0.0001; PPRS<0.0001). Similar trends were seen in ECLIPSE. The area under the receiver operator characteristic curve for a model containing family history and PRS was significantly higher than a model with PRS (p=0.00035) in NHWs and a model with family history (p<0.0001) alone in NHWs and AAs. Both family history and PRS were significantly associated with measures of quantitative emphysema and airway thickness. There was a weakly positive interaction between family history and the PRS under the additive, but not multiplicative scale in NHWs (relative excess risk due to interaction=0.48, p=0.04). Mediation analyses found that a significant proportion of the effect of family history on COPD was mediated through PRS in NHWs (16.5%, 95% CI 9.4% to 24.3%), but not AAs.ConclusionFamily history and the PRS provide complementary information for predicting COPD and related outcomes. Future studies can address the impact of obtaining both measures in clinical practice.

Improvement in psychological wellbeing among adolescents with a substance use disorder attending an outpatient treatment programme

2021 ◽  
pp. 1-8
Author(s):  
N.M. Gamage ◽  
C. Darker ◽  
B.P. Smyth
Keyword(s):  
Substance Use ◽  
Psychological Symptoms ◽  
Significant Proportion ◽  
Cannabis Use ◽  
Psychological Wellbeing ◽  
Substance Use Treatment ◽  
Disruptive Behaviour ◽  
Treatment Programme ◽  
The Impact

Objectives: Adolescents with substance use disorders (SUDs) exhibit high rates of comorbid psychological problems. This study aimed to examine the impact of an outpatient substance use treatment programme upon the psychological wellbeing of adolescents. Methods: A prospective study was carried out examining psychological symptoms in a group of adolescents attending the Youth Drug and Alcohol (YoDA) Addiction Service in Dublin. Participants were treated with evidenced based psychological models such as cognitive behavioural therapy, motivational interviewing and systemic family therapy. The Becks Youth Inventory was utilised to assess psychological symptoms at treatment entry and repeated three months later at follow up. Results: Among 36 adolescents who were included in this study, poly-substance misuse was the norm. Almost three-quarter had a cannabis use disorder (CUD). There were significant reductions in mean subscale scores of depression (56.0 to 50.8, p = 0.003), anger (55.2 to 49.5, p < 0.001) and disruptive behaviour (61.6 to 56.5, p = 0.002) at follow up. Although there wasn’t a statistically significant reduction in mean scores for anxiety, we observed a significant proportion of participants (p = 0.008) improving and moving out of a moderate to severe symptom range when examined by category. This was also the case for self-concept (p = 0.04). Furthermore this study revealed a positive correlation between the reduction in days of cannabis use and reduction in depressive scores (Pearson correlation 0.49, p = 0.01) among those with a CUD. Conclusion: The findings indicate that substance use treatment for adolescents is associated with important psychological and behavioural improvements.

scholarly journals Prostate cancer and the human papilloma virus: causative association, role of vaccines, and the impact of the COVID-19 pandemic

2021 ◽  
Author(s):  
Naomi Morka ◽  
Joseph M. Norris ◽  
Mark Emberton ◽  
Daniel Kelly
Keyword(s):  
Prostate Cancer ◽  
Human Papilloma Virus ◽  
Hpv Vaccination ◽  
Significant Proportion ◽  
Vaccine Uptake ◽  
Papilloma Virus ◽  
Vaccination Campaigns ◽  
The Impact ◽  
Hpv Vaccine Uptake

AbstractProstate cancer affects a significant proportion of men worldwide. Evidence from genetic and clinical studies suggests that there may be a causal association between prostate cancer and the human papilloma virus (HPV). As HPV is a vaccine-preventable pathogen, the possibility of a role in prostate cancer causation may reinforce the importance of effective HPV vaccination campaigns. This is of particular relevance in light of the COVID-19 pandemic, which may have considerable effects on HPV vaccine uptake and distribution.

scholarly journals The impact of theory-based messages on COVID-19 vaccination intentions: a structured summary of a study protocol for a randomised controlled trial

Trials ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Ben Young ◽  
Marie Kotzur ◽  
Lauren Gatting ◽  
Carissa Bonner ◽  
Julie Ayre ◽  
...  
Keyword(s):  
Online Survey ◽  
Controlled Trial ◽  
Significant Proportion ◽  
General Information ◽  
School Level ◽  
Text And Image ◽  
Post Intervention ◽  
Full Protocol ◽  
The Impact ◽  
Illness Coherence

Abstract Objectives Uptake of vaccination against COVID-19 is key to controlling the pandemic. However, a significant proportion of people report that they do not intend to have a vaccine, often because of concerns they have about vaccine side effects or safety. This study will assess the impact of theory-based messages on COVID-19 vaccination intention, drawing on the Necessity-Concerns framework to address previously reported beliefs and concerns about COVID-19 vaccination, and assess whether hypothesised variables (illness coherence, perceived necessity and concerns) mediate change in vaccination intention. Trial design Prospective, parallel two-arm, individually randomised (1:1) trial. Participants Adults aged over 18 years, living in Scotland and not vaccinated for COVID-19. A quota sampling approach will be used with the aim of achieving a nationally representative sample on gender, region and ethnic group, with oversampling of individuals with no educational qualifications or with only school-level qualifications. Intervention and comparator Intervention: Brief exposure to online text and image-based messages addressing necessity beliefs and concerns about COVID-19 vaccination. Comparator: Brief exposure to online text and image-based messages containing general information about COVID-19 and COVID-19 vaccination. Main outcomes Primary outcome: Self-reported intention to receive a vaccine for COVID-19 if invited, immediately post-intervention. Secondary outcomes: Self-reported COVID-19 illness coherence, perceived necessity of a COVID-19 vaccine and concerns about a COVID-19 vaccine, immediately post-intervention. Randomisation Quasi-randomisation performed automatically by online survey software, by creating a variable derived from the number of seconds in the minute that the participant initiates the survey. Participants starting the survey at 0-14 or 30-44 seconds in the minute are allocated to the intervention and 15-29 or 45-59 seconds to the comparator. Blinding (masking) Participants will not be blinded to group assignment but will not be informed of the purpose of the study until they have completed the follow-up survey. Investigators will be blinded to allocation as all procedures will be undertaken digitally and remotely without any investigator contact with participants. Numbers to be randomised (sample size) A total of 1,094 will be randomised 1:1 into two groups with 547 individuals in each. Trial Status Protocol version number 1.0, 26th February 2021. Recruitment status: Not yet recruiting, set to start April 2021 and end April 2021. Trial registration ClinicalTrials.gov, NCT04813770, 24th March 2021. Full protocol The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.

Hohlraum-Driven Mid-Z(SiO2) Double-Shell Implosions on the Omega Laser Facility and Their Scaling to NIF

2009 ◽  
Vol 103 (14) ◽  
Author(s):  
H. F. Robey ◽  
P. A. Amendt ◽  
J. L. Milovich ◽  
H.-S. Park ◽  
A. V. Hamza ◽  
...  
Keyword(s):  
Laser Facility ◽  
Omega Laser

Generation of Efficient Terahertz Radiation by Relativistic Self-Focusing of A Cosh-Gaussian Laser Beam in A Magnetized Plasma

2021 ◽  
Author(s):  
Gunjan Purohit ◽  
Bineet Gaur ◽  
Pradeep Kothiyal ◽  
Amita Raizada
Keyword(s):  
Laser Beam ◽  
Numerical Study ◽  
The Self ◽  
Magnetized Plasma ◽  
Thz Radiation ◽  
Gaussian Laser Beam ◽  
Plasma Parameters ◽  
Gaussian Profile ◽  
Self Focusing ◽  
Incident Laser Intensity

Abstract This paper presents a scheme for the generation of terahertz (THz) radiation by self-focusing of a cosh-Gaussian laser beam in the magnetized and rippled density plasma, when relativistic nonlinearity is operative. The strong coupling between self-focused laser beam and pre-existing density ripple produces nonlinear current that originates THz radiation. THz radiation is produced by the interaction of the cosh-Gaussian laser beam with electron plasma wave under the appropriate phase matching conditions. Expressions for the beamwidth parameter of cosh-Gaussian laser beam and the electric vector of the THz radiation have been obtained using higher-order paraxial theory and solved numerically. The self-focusing of the cosh-Gaussian laser beam and its effect on the generated THz amplitude have been studied for specific laser and plasma parameters. Numerical study has been performed on various values of the decentered parameter, incident laser intensity, magnetic field, and relative density. The results have also been compared with the paraxial region as well as the Gaussian profile of laser beam. Numerical results suggest that the self-focusing of the cosh-Gaussian laser beam and the amplitude of THz radiation increase in the extended paraxial region compared to the paraxial region. It is also observed that the focusing of the cosh-Gaussian laser beam in the magnetized plasma and the amplitude of the THz radiation increases at higher values of the decentered parameter.

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