Experimental Modeling of Cosmological Inflation with Metamaterials

Recently we demonstrated that mapping of monochromatic extraordinary light distribution in a hyperbolic metamaterial along some spatial direction may model the flow of time and create an experimental toy model of the big bang. Here we extend this model to emulate cosmological inflation. This idea is illustrated in experiments performed with two-dimensional plasmonic hyperbolic metamaterials. Spatial dispersion which is always present in hyperbolic metamaterials results in scale-dependent (fractal) structure of the inflationary "metamaterial spacetime". This feature of our model replicates hypothesized fractal structure of the real observable universe.Comment: 17 pages, 3 figures. This version is accepted for publication in Physics Letters

A transition of atmospheric emissions of particles and gases from on-road heavy-duty trucks

The transition, in extent and characteristics, of atmospheric emissions caused by the modernization of the heavy-duty on-road fleet was studied utilizing roadside measurements. Emissions of particle number (PN), particle mass (PM), black carbon (BC), nitrogen oxides (NOx), carbon monoxide (CO), hydrocarbon (HC), particle size distributions, and particle volatility were measured from 556 individual heavy-duty trucks (HDTs). Substantial reductions in PM, BC, NOx, CO, and to a lesser extent PN were observed from Euro III to Euro VI HDTs by 99 %, 98 %, 93 %, and 57 % for the average emission factors of PM, BC, NOx, and CO, respectively. Despite significant total reductions in NOx emissions, the fraction of NO2 in the NOx emissions increased continuously from Euro IV to Euro VI HDTs. Larger data scattering was evident for PN emissions in comparison to solid particle number (SPN) for Euro VI HDTs, indicating a highly variable fraction of volatile particle components. Particle size distributions of Euro III to enhanced environmentally friendly vehicle (EEV) HDTs were bimodal, whereas those of Euro VI HDTs were nucleation mode dominated. High emitters disproportionately contributed to a large fraction of the total emissions with the highest-emitting 10 % of HDTs in each pollutant category being responsible for 65 % of total PM, 70 % of total PN, and 44 % of total NOx emissions. Euro VI HDTs, which accounted for 53 % of total kilometres driven by Swedish HDTs, were estimated to only contribute to 2 %, 6 %, 12 %, and 47 % of PM, BC, NOx, and PN emissions, respectively. A shift to a fleet dominated by Euro VI HDTs would promote a transition of atmospheric emissions towards low PM, BC, NOx, and CO levels. Nonetheless, reducing PN, SPN, and NO2 emissions from Euro VI HDTs is still important to improve air quality in urban environments

The Acceptability of Internet-Based Treatment and Characteristics of an Adult Sample with Obsessive Compulsive Disorder: An Internet Survey

Background: Obsessive-compulsive disorder (OCD) is a disabling anxiety disorder, but most individuals delay seeking treatment. Internet-based cognitive behavioural therapy (iCBT) is an innovative service delivery method that may help to improve access to care, but the acceptability to consumers of such programs has not yet been established. Methodology: People with symptoms of OCD were invited to complete an online survey enquiring about demographic characteristics, symptom severity, and acceptability of Internet-based treatment. Demographic and symptom severity data were compared with people with OCD identified in a national epidemiological survey and with a sample of patients with OCD from a specialist outpatient anxiety clinic. Participants: 129 volunteers to an online Internet survey, 135 patients at a specialist anxiety disorders outpatient clinic, and 297 cases identified in a national epidemiological survey. Main Measures: Demographic characteristics, and severity of symptoms as measured by the Kessler 10-Item scale, the 12-item World Health Organisation Disability Assessment Schedule - Second Edition and the Yale Brown Obsessive Compulsive Scale - Self Report Version. Principal Findings: The Internet sample was similar demographically but reported more severe symptoms than the comparison groups, although had similar severity of symptoms of OCD compared with other clinical samples reported in the literature. Participants reported Internet-based treatment for OCD would be highly acceptable. Conclusions: Internet-based treatment may reduce barriers to accessing treatment to people with OCD. Individuals in this study were similar demographically to other samples and had similar severity of symptoms as those identified in other clinical samples, suggesting that Internet-based treatment using techniques employed in face-to-face treatment may be effective in this group. Internet-based treatments for OCD need to be developed and evaluated

Evaluation of a Web Portal for Improving Public Access to Evidence-Based Health Information and Health Literacy Skills: A Pragmatic Trial

Background: Using the conceptual framework of shared decision-making and evidence-based practice, a web portal was developed to serve as a generic (non disease-specific) tailored intervention to improve the lay public’s health literacy skills. Objective: To evaluate the effects of the web portal compared to no intervention in a real-life setting. Methods: A pragmatic randomised controlled parallel trial using simple randomisation of 96 parents who had children aged ,4 years. Parents were allocated to receive either access to the portal or no intervention, and assigned three tasks to perform over a three-week period. These included a searching task, a critical appraisal task, and reporting on perceptions about participation. Data were collected from March through June 2011. Results: Use of the web portal was found to improve attitudes towards searching for health information. This variable was identified as the most important predictor of intention to search in both samples. Participants considered the web portal to have good usability, usefulness, and credibility. The intervention group showed slight increases in the use of evidencebased information, critical appraisal skills, and participation compared to the group receiving no intervention, but these differences were not statistically significant. Conclusion: Despite the fact that the study was underpowered, we found that the web portal may have a positive effect on attitudes towards searching for health information. Furthermore, participants considered the web portal to be a relevant tool. It is important to continue experimenting with web-based resources in order to increase user participation in health care decision-making. Trial Registration: ClinicalTrials.gov NCT0126679

Connective tissue growth factor in tumor pathogenesis

Key roles for connective tissue growth factor (CTGF/CCN2) are demonstrated in the wound repair process where it promotes myofibroblast differentiation and angiogenesis. Similar mechanisms are active in tumor-reactive stroma where CTGF is expressed. Other potential roles include prevention of hypoxia-induced apoptosis and promoting epithelial-mesenchymal transistion (EMT). CTGF expression in tumors has been associated to both tumor suppression and progression. For example, CTGF expression in acute lymphoblastic leukemia, breast, pancreas and gastric cancer correlates to worse prognosis whereas the opposite is true for colorectal, lung and ovarian cancer. This discrepancy is not yet understood

A survey of preferences for respiratory support in the intensive care unit for patients with acute hypoxaemic respiratory failure

Publisher Copyright: © 2023 The Authors. Acta Anaesthesiologica Scandinavica published by John Wiley & Sons Ltd on behalf of Acta Anaesthesiologica Scandinavica Foundation.Background: When caring for mechanically ventilated adults with acute hypoxaemic respiratory failure (AHRF), clinicians are faced with an uncertain choice between ventilator modes allowing for spontaneous breaths or ventilation fully controlled by the ventilator. The preferences of clinicians managing such patients, and what motivates their choice of ventilator mode, are largely unknown. To better understand how clinicians' preferences may impact the choice of ventilatory support for patients with AHRF, we issued a survey to an international network of intensive care unit (ICU) researchers. Methods: We distributed an online survey with 32 broadly similar and interlinked questions on how clinicians prioritise spontaneous or controlled ventilation in invasively ventilated patients with AHRF of different severity, and which factors determine their choice. Results: The survey was distributed to 1337 recipients in 12 countries. Of these, 415 (31%) completed the survey either fully (52%) or partially (48%). Most respondents were identified as medical specialists (87%) or physicians in training (11%). Modes allowing for spontaneous ventilation were considered preferable in mild AHRF, with controlled ventilation considered as progressively more important in moderate and severe AHRF. Among respondents there was strong support (90%) for a randomised clinical trial comparing spontaneous with controlled ventilation in patients with moderate AHRF. Conclusions: The responses from this international survey suggest that there is clinical equipoise for the preferred ventilator mode in patients with AHRF of moderate severity. We found strong support for a randomised trial comparing modes of ventilation in patients with moderate AHRF.Peer reviewe

Evaluation of a real-time virtual intervention to empower persons living with HIV to use therapy self-management: study protocol for an online randomized controlled trial

Background: Living with HIV makes considerable demands on a person in terms of self-management, especially as regards adherence to treatment and coping with adverse side-effects. The online HIV Treatment, Virtual Nursing Assistance and Education (Virus de I'immunodeficience Humaine-Traitement Assistance Virtuelle Infirmiere et Enseignement; VIH-TAVIE (TM)) intervention was developed to provide persons living with HIV (PLHIV) with personalized follow-up and real-time support in managing their medication intake on a daily basis. An online randomized controlled trial (RCT) will be conducted to evaluate the efficacy of this intervention primarily in optimizing adherence to combination anti-retroviral therapy (ART) among PLHIV.Methods/design: A convenience sample of 232 PLHIV will be split evenly and randomly between an experimental group that will use the web application, and a control group that will be handed a list of websites of interest. Participants must be aged 18 years or older, have been on ART for at least 6 months, and have internet access. The intervention is composed of four interactive computer sessions of 20 to 30 minutes hosted by a virtual nurse who engages the PLHIV in a skills-learning process aimed at improving self-management of medication intake. Adherence constitutes the principal outcome, and is defined as the intake of at least 95% of the prescribed tablets. The following intermediary measures will be assessed: self-efficacy and attitude towards antiretroviral medication, symptom-related discomfort, and emotional support. There will be three measurement times: baseline (T0), after 3 months (T3) and 6 months (T6) of baseline measurement. The principal analyses will focus on comparing the two groups in terms of treatment adherence at the end of follow-up at T6. An intention-to-treat (ITT) analysis will be carried out to evaluate the true value of the intervention in a real context.Discussion: Carrying out this online RCT poses various challenges in terms of recruitment, ethics, and data collection, including participant follow-up over an extended period. Collaboration between researchers from clinical disciplines (nursing, medicine), and experts in behavioral sciences information technology and media will be crucial to the development of innovative solutions to supplying and delivering health services

Seasonal and spatial evasion of mercury from the western Mediterranean Sea

Continuous measurements of gaseous elemental mercury (GEM) in air and dissolved gaseous mercury (DGM) in surface seawater were performed during two oceanographic campaigns (Fenice 2011 (25/10-11/11) and Fenice 2012 (11-29/8)), carried out in the Tyrrhenian Sea (Fenice 211), western Mediterranean Sea and the Atlantic Ocean (Fenice 2012) as part of the GMOS project (Global Mercury Observation System). Measured GEM and DGM were used to estimate the air-sea exchange of elemental mercury by using a two-thin film gas exchange model. Measured GEM concentrations showed significantly higher values in fall (1.7 +/- 0.4 ng m(-3)) compared to summer (1.5 +/- 03 ng m(-3),

Comparison of two measurement methods of dissolved gaseous mercury concentrations and estimations of supersaturation grade and mercury fluxes during a research campaign at the Mediterranean Sea

Dissolved gaseous mercury (DGM) concentrations and gaseous elemental mercury (GEM) concentrations were measured during an oceanographic campaign in the Mediterranean Sea. The DGM concentrations were measured using two different methods, a manual-and an automated method. The manual method was used to obtain DGM depth profiles at several stations throughout the campaign. The automated device measured DGM concentrations continuously at a depth of 4 m. Gaseous elemental mercury (GEM) concentrations in air were measured continuously at the bridge deck. The objectives were to achieve DGM depth profiles, compare the manual-and automated DGM measurement methods, to calculate the supersaturation grades of the sea and the evasional fluxes from the sea surface. Depth profiles of the four measured stations show no diurnal variations. The manual-and the automated method show good compliance. Supersaturation grades are high due to high DGM values and low GEM concentrations. Fluxes of Hg from the sea surface are more dependent on the wind speed than on the supersaturation grade according to the flux models used