586 research outputs found
Plasma wakefield accelerators
No full textEdda Gschwendtner and Patric Muggli discuss the concept of plasma wakefield acceleration and
its potential for future particle colliders and other applications
Towards a Proposal for an Advanced Linear Collider Report on the Advanced and Novel Accelerators for High Energy Physics Roadmap Workshop, CERN, Geneva, April 2017
No full textThe Advanced and Novel Accelerators for High Energy Physics Roadmap (ANAR)
Workshop was organized on the initiative of the Advanced and Novel Accelerator (ANA)
panel of the International Committee for Future Accelerators 1
(ICFA-ANA panel, members
of this panel are listed below). It was chaired by B. Cros and co-chaired by P. Muggli.
The workshop focused on the application of ANAs to high energy physics (HEP), keeping
in mind the ultimate goal of an electron/positron (e−/e+) collider or an electron/proton
(e−/p+) collider, both at the energy frontier.
The development of ANAs is conducted at universities and national laboratories worldwide.
The community is thematically broad and diverse, in particular since lasers suitable
for ANA research (multi-terawatt peak power, a few tens of femtosecond-long pulses) and
acceleration of electrons to tens to hundreds of mega electron volts became commercially
available. The community spans over several continents (Europe, America, Asia), including
more than 62 laboratories in more than 20 countries.
It is among the missions of the ICFA-ANA panel to feature the amazing progress made
with ANAs, to provide international coordination and to foster international collaborations
towards a future HEP collider.
The ANAR workshop was organized as a first step towards the development of an
international ANA scientific roadmap for such an advanced linear collider, with the delivery
of a technical design report by 2035. The first step towards this goal includes taking stock
of the scientific landscape, outlining global priorities for scientific progress, identifying
facilities necessary for this progress, identifying existing and local roadmaps, and imagining
strategies to encourage the development of a genuinely international roadmap
SARS-CoV-2 Ig G among healthcare workers and the general population
No full textIt is assumed that healthcare workers are at the highest risk to be infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, few data from healthcare workers who do not primarily take care of patients with SARS-CoV-2 infection support this assumption. We investigated the prevalence of immunoglobulin G (Ig G) against SARS-CoV-2 among healthcare workers who do not primarily take care of patients with SARS-CoV-2 infection and the general population in a well-defined geographical area. The first part of the study was conducted in May 2020 in Val Mesolcina (Southern Switzerland), a valley with ~8000 inhabitants. All healthcare workers were invited. All participants (n = 488) of the Swiss Longitudinal Cohort Study (SWICOS), a cohort representative of the general population, were also invited. Circulating Ig G against spike protein subunit 1 of SARS-CoV-2 were tested in each subject. Subjects with positive Ig G were tested again after 6 months. The condition of being a healthcare worker, rather than a part of the general population, was tested as a predictor of seroprevalence positivity by both simple and multiple (adjusted for age and sex) logistic regression. Eleven (2.6%) of the 423 SWICOS participants and 46 (16%) out of 289 healthcare workers were positive for antibodies against SARS-CoV-2. The seroprevalence OR was 7.01 (95% CI: 3.53–15.47) for healthcare workers as compared to SWICOS participants. After adjusting for age and gender, the seroprevalence OR was 5.13 (95% CI: 2.54–10.40). About three quarters of the subjects in the SWICOS (73%) and in healthcare (79%) group with a previous positive serology still presented positive Ig G against the SARS-CoV-2 after 6 months. The present seroprevalence data point out that the SARS-CoV-2 infection is seven times higher among healthcare workers than in the general population of Val Mesolcina. Efforts to effectively protect all the healthcare personnel are needed
Vitamin D status among male late adolescents living in Southern Switzerland: Role of body composition and lifestyle
No full textBACKGROUND: Poor vitamin D status is a worldwide health problem. Yet, knowledge about vitamin D status among adolescents in Southern Europe is limited. This study investigated concentrations and modulating factors of vitamin D in a healthy population of male late adolescents living in Southern Switzerland. METHODS: All apparently healthy subjects attending for the medical evaluation before the compulsory military service in Southern Switzerland during 2014-2016 were eligible. Dark-skin subjects, subjects on vitamin D supplementation or managed with diseases or drugs involved in vitamin D metabolism were excluded. Anthropometric measurements (body height, weight, fat percentage, mid-upper arm and waist circumference) and blood sampling for total 25-hydroxy-vitamin D, total cholesterol and ferritin concentrations testing, were collected. Participants filled in a structured questionnaire addressing their lifestyle. Characteristics of the subjects with adequate (≥50 nmol/L-≤250 nmol/L) and insufficient (<50 nmol/L) vitamin D values were compared by Kruskal-Wallis test or χ2 test. Odds ratios for 25-hydroxy-vitamin D insufficiency were calculated by univariate and AIC-selected multiple logistic regression models. RESULTS: A total of 1045 subjects volunteered to participate in the study. Insufficient concentrations of vitamin D were detected in 184 (17%). The season of measurement was the most significant factor associated with vitamin D levels and approximately 40% of subjects presented insufficient vitamin D concentrations in winter. After model selection, body fat percentage, frequency and site of recreational physical activity, and the seasonality were significantly associated with the risk of vitamin D insufficiency. CONCLUSIONS: Among healthy male late adolescents in Southern Switzerland, about one every fourth subject presents a poor vitamin D status in non-summer seasons. Body fat percentage, frequent and outdoor recreational physical activity are modulating factors of vitamin D status in this population
"Efforts to Reprioritise the Agenda" in China: British American Tobacco's Efforts to Influence Public Policy on Secondhand Smoke in China.
No full textBACKGROUND: Each year, 540 million Chinese are exposed to secondhand smoke (SHS), resulting in more than 100,000 deaths. Smoke-free policies have been demonstrated to decrease overall cigarette consumption, encourage smokers to quit, and protect the health of nonsmokers. However, restrictions on smoking in China remain limited and ineffective. Internal tobacco industry documents show that transnational tobacco companies (TTCs) have pursued a multifaceted strategy for undermining the adoption of restrictions on smoking in many countries. METHODS AND FINDINGS: To understand company activities in China related to SHS, we analyzed British American Tobacco's (BAT's) internal corporate documents produced in response to litigation against the major cigarette manufacturers to understand company activities in China related to SHS. BAT has carried out an extensive strategy to undermine the health policy agenda on SHS in China by attempting to divert public attention from SHS issues towards liver disease prevention, pushing the so-called "resocialisation of smoking" accommodation principles, and providing "training" for industry, public officials, and the media based on BAT's corporate agenda that SHS is an insignificant contributor to the larger issue of air pollution. CONCLUSIONS: The public health community in China should be aware of the tactics previously used by TTCs, including efforts by the tobacco industry to co-opt prominent Chinese benevolent organizations, when seeking to enact stronger restrictions on smoking in public places
The cardiovascular protective role of docosahexaenoic acid.
No full textDietary fish oils rich in n-3 polyunsaturated fatty acids can modulate a diverse range of factors contributing to cardiovascular disease. This study examined the relative roles of eicosapentaenoic acid (20:5 n-3; EPA) and docosahexaenoic acid (22:6 n-3; DHA) which are the principal n-3 polyunsaturated fatty acids regarded as candidates for cardioprotective actions. At low dietary intakes (0.4–1.1% of energy (%en)), docosahexaenoic acid but not eicosapentaenoic acid inhibited ischaemia-induced cardiac arrhythmias. At intakes of 3.9–10.0%en, docosahexaenoic acid was more effective than eicosapentaenoic acid at retarding hypertension development in spontaneously hypertensive rats (SHR) and inhibiting thromboxane-like vasoconstrictor responses in aortas from SHR. In stroke-prone SHR with established hypertension, docosahexaenoic acid (3.9–10.0%en) retarded the development of salt-loading induced proteinuria but eicosapentaenoic acid alone was ineffective. The results demonstrate that purified n-3 polyunsaturated fatty acids mimic the cardiovascular actions of fish oils and imply that docosahexaenoic acid may be the principal active component conferring cardiovascular protection.Peter McLennan, Peter Howe, Mahinda Abeywardena, Reto Muggli, Daniel Raederstorff, Mark Mano, Tim Rayner and Richard Hea
Maternal micronutrient consumption periconceptionally and during pregnancy: a prospective cohort study
No full textOBJECTIVE:To examine overall micronutrient intake periconceptionally and throughout pregnancy in a population-based cohort of Australian women. DESIGN:In a prospective cohort study, micronutrient dosages were extracted from self-reported maternal supplement use, recorded pre-conception, and for each trimester of pregnancy. A food frequency scale (DQESv2) captured usual maternal diet for gestational weeks 14-26. The influence of sociodemographic and lifestyle factors associated with supplement use was examined using logistic regression, and changes in micronutrient intakes prior to and throughout pregnancy were assessed using repeated-measures ANOVA analyses. SETTING:Metropolitan hospital sites in Melbourne, Australia. SUBJECTS:Women with a viable singleton pregnancy were recruited at less than 19 weeks' gestation (n 2146). RESULTS:Compared with non-users, women using supplements during pregnancy were more likely to have planned their pregnancy, be >25 years old, primiparous, Caucasian, non-smokers, have a tertiary education and be consuming a folate-rich diet. Intakes of folate, Fe and Zn were significantly lower in the periconceptional period, compared with other periods (P<0·001). Intakes below Recommended Daily Intake levels were common both periconceptionally and throughout pregnancy, with 19-46 % of women not meeting the Recommended Daily Intake for folate, 68-82 % for Fe and 17-36 % for Zn. Conversely, 15-19 % of women consumed beyond the recommended Upper Limit for folate and 11-24 % for Fe. CONCLUSIONS:The study highlights the need for improved public health education on nutritional needs during pregnancy, especially among women with lower educational achievements and income.Michelle Livock, Peter J Anderson, Sharon Lewis, Stephen Bowden, Evelyne Muggli and Jane Hallida
Schlieren Imaging for the Determination of the Radius of an Excitated Rubidium Column
No full textAWAKE develops a new plasma wakefield accelerator using the CERN SPS proton bunch as a driver Muggli et al. (2017). The proton bunch propagates through a 10m long rubidium plasma, induced by an ionizing laser pulse. The co-propagation of the laser pulse with the proton bunch seeds the self modulation instability of the proton bunch that transforms the bunch to a train with hundreds of bunchlets which drive the wakefields. Therefore the plasma radius must exceed the proton bunch radius. Schlieren imaging is proposed to determine the plasma radius on both ends of the vapor source. We use Schlieren imaging to estimate the radius of a column of excited rubidium atoms. A tunable, narrow bandwidth laser is split into a beam for the excitation of the rubidium vapor and for the visualization using Schlieren imaging. With a laser wavelength very close to the D2 transition line of rubidium (λ≈780nm), it is possible to excite a column of rubidium atoms in a small vapor source, to record a Schlieren signal of the excitation column and to estimate its radius. We describe the method and show the results of the measurement.AWAKE develops a new plasma wakefield accelerator using the CERN SPS proton bunch as a driver Muggli et al. (2017). The proton bunch propagates through a 10m long rubidium plasma, induced by an ionizing laser pulse. The co-propagation of the laser pulse with the proton bunch seeds the self modulation instability of the proton bunch that transforms the bunch to a train with hundreds of bunchlets which drive the wakefields. Therefore the plasma radius must exceed the proton bunch radius. Schlieren imaging is proposed to determine the plasma radius on both ends of the vapor source. We use Schlieren imaging to estimate the radius of a column of excited rubidium atoms. A tunable, narrow bandwidth laser is split into a beam for the excitation of the rubidium vapor and for the visualization using Schlieren imaging. With a laser wavelength very close to the D2 transition line of rubidium ( λ≈780nm ), it is possible to excite a column of rubidium atoms in a small vapor source, to record a Schlieren signal of the excitation column and to estimate its radius. We describe the method and show the results of the measurement.AWAKE develops a new plasma wakefield accelerator using the CERN SPS proton bunch as a driver. The proton bunch propagates through a 10 m long rubidium plasma, induced by an ionizing laser pulse. The co-propagation of the laser pulse with the proton bunch seeds the self modulation instability of the proton bunch that transforms the bunch to a train with hundreds of bunchlets which drive the wakefields. Therefore the plasma radius must exceed the proton bunch radius. Schlieren imaging is proposed to determine the plasma radius on both ends of the vapor source. We use Schlieren imaging to estimate the radius of a column of excited rubidium atoms. A tunable, narrow bandwidth laser is split into a beam for the excitation of the rubidium vapor and for the visualization using Schlieren imaging. With a laser wavelength very close to the D2 transition line of rubidium (780 nm), it is possible to excite a column of rubidium atoms in a small vapor source, to record a Schlieren signal of the excitation column and to estimate its radius. We describe the method and show the results of the measurement
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