35 research outputs found
Measurement of an Elongation of the Pion Source in Z Decays
We measure Bose-Einstein correlations between like-sign charged pion pairs in
hadronic Z decays with the L3 detector at LEP. The analysis is performed in
three dimensions in the longitudinal center-of-mass system. The pion source is
found to be elongated along the thrust axis with a ratio of transverse to
longitudinal radius of
The upgrade of the ALICE TPC with GEMs and continuous readout
The upgrade of the ALICE TPC will allow the experiment to cope with the high interaction rates foreseen for the forthcoming Run 3 and Run 4 at the CERN LHC. In this article, we describe the design of new readout chambers and front-end electronics, which are driven by the goals of the experiment. Gas Electron Multiplier (GEM) detectors arranged in stacks containing four GEMs each, and continuous readout electronics based on the SAMPA chip, an ALICE development, are replacing the previous elements. The construction of these new elements, together with their associated quality control procedures, is explained in detail. Finally, the readout chamber and front-end electronics cards replacement, together with the commissioning of the detector prior to installation in the experimental cavern, are presented. After a nine-year period of R&D, construction, and assembly, the upgrade of the TPC was completed in 2020.publishedVersio
Rising rural body-mass index is the main driver of the global obesity epidemic in adults
Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities 1,2 . This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity 3�6 . Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55 of the global rise in mean BMI from 1985 to 2017�and more than 80 in some low- and middle-income regions�was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing�and in some countries reversal�of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories. © 2019, The Author(s)
Experimental studies on pollenmediated gene flow in Sorghum bicolor (L.) Moench using malesterile bait plants
Information on the potential of pollen mediated gene flow (PMGF) in sorghum is required for ensuring varietal purity and to mitigate risk transgenic gene flow. Replicated trials were conducted in Kenya using a local landrace, ‘Ochuti’ as pollen donor surrounded by male-sterile pollen baits. Frequency of PMGF decreased with the increase of distance from pollen sources and was significantly influenced by wind direction and speed. Anther dehiscence correlated with increase in vapour pressure deficit in the morning. A negative exponential regression model with logarithmic transformation of PMGF and square-root transformation of distance from source field best fitted the data. Up to 50% of female florets on a male sterile (MS) plant were pollinated at 1 m from pollen source and declined to 14% at 10 m. The maximum distance of PMGF using the PMGF model, based on a threshold of one seed per MS plant, was 203 m when data above the 95th percentile is considered. However, in the presence of self-produced pollen of male-fertile target plants, the possibility of long-distance cross-pollination may be very low
Beyond a Cross‐Cultural Definition of Child Maltreatment: Comparing Immigrants From the Caucasus and European Countries of the Former Soviet Union
Investigation of fast particle driven instabilities by 2D electron cyclotron emission imaging on ASDEX Upgrade
Detailed measurements of the 2D mode structure of Alfv´en instabilities in the current ramp-up phase of neutral beam heated discharges were performed on ASDEX Upgrade, using the electron cyclotron emission imaging (ECEI) diagnostic. This paper focuses on the observation of reversed shear Alfv´en eigenmodes (RSAEs) and bursting modes that, with the use of the information from ECEI, have been identified as beta-induced Alfv´en eigenmodes (BAEs). Both RSAEs with first and second radial harmonic mode structures were observed. Calculations with the linear gyro-kinetic code LIGKA revealed that the ratio of the damping rates and the frequency difference between the first and second harmonic modes strongly depended on the shape of the qprofile. The bursting character of the BAE type modes, which were radially localized to rational q surfaces, was observed to sensitively depend on the plasma parameters, ranging from strongly bursting to almost steady state