2,230 research outputs found
Top quark results at CDF
A selection of the most recent CDF analyses on the top quark
physics is reported. The reviewed results are based on the Tevatron Run II data. An emphasis is put on comparison of experimental results to the latest theoretical models and on the first observation of the single top production at Tevatron
Hydrogels for three-dimensional ionizing-radiation dosimetry
Radiation-sensitive gels are among the most recent and promising developments for radiation therapy (RT) dosimetry. RT dosimetry has the twofold goal of ensuring the quality of the treatment and the radiation protection of the patient. Benchmark dosimetry for acceptance testing and commissioning of RT systems is still based on ionization chambers. However, even the smallest chambers cannot resolve the steep dose gradients of up to 30–50% per mm generated with the most advanced techniques. While a multitude of systems based, e.g., on luminescence, silicon diodes and radiochromic materials have been developed, they do not allow the truly continuous 3D dose measurements offered by radiation-sensitive gels. The gels are tissue equivalent, so they also serve as phantoms, and their response is largely independent of radiation quality and dose rate. Some of them are infused with ferrous sulfate and rely on the radiation-induced oxidation of ferrous ions to ferric ions (Fricke-gels). Other formulations consist of monomers dispersed in a gelatinous medium (Polyacrylamide gels) and rely on radiation-induced polymerization, which creates a stable polymer structure. In both gel types, irradiation causes changes in proton relaxation rates that are proportional to locally absorbed dose and can be imaged using magnetic resonance imaging (MRI). Changes in color and/or opacification of the gels also occur upon irradiation, allowing the use of optical tomography techniques. In this work, we review both Fricke and polyacrylamide gels with emphasis on their chemical and physical properties and on their applications for radiation dosimetry
39-K Bose-Einstein condensate with tunable interactions
We produce a Bose-Einstein condensate of 39-K atoms. Condensation of this
species with naturally small and negative scattering length is achieved by a
combination of sympathetic cooling with 87-Rb and direct evaporation,
exploiting the magnetic tuning of both inter- and intra-species interactions at
Feshbach resonances. We explore tunability of the self-interactions by studying
the expansion and the stability of the condensate. We find that a 39-K
condensate is interesting for future experiments requiring a weakly interacting
Bose gas.Comment: 5 page
The economic burden of obesity in Italy: a cost‑of‑illness study
Background Obesity is a complex health disorder that significantly increases the risk of several chronic diseases, and it has been associated with a 5–20-year decrease in life expectancy. The prevalence of obesity is increasing steadily worldwide and Italy follows this trend with an increase of almost 30% in the adult obese population in the last 3 decades. Previous studies estimated that 2–4% of the total health expenditure in Europe is attributed to obesity and it is projected to double by 2050. Currently, there is a lack of sufficient knowledge on the burden of obesity in Italy and most relevant estimates are derived from international studies. The aim of this study is to estimate the direct and indirect costs of obesity in Italy, taking 2020 as the reference year.
Methods Based on data collected from the literature, a quantitative cost-of-illness (COI) study was performed from a societal perspective focussing on the adult obese population (Body Mass Index (BMI) ≥ 30 kg/m2) in Italy.
Results The study indicated that the total costs attributable to obesity in Italy amounted to €13.34 billion in 2020 (95% credible interval: €8.99 billion < μ < €17.80 billion). Direct costs were €7.89 billion, with cardiovascular diseases (CVDs) having the highest impact on costs (€6.66 billion), followed by diabetes (€0.65 billion), cancer (€0.33 billion), and bariatric surgery (€0.24 billion). Indirect costs amounted to €5.45 billion, with almost equal contribution of absenteeism (€2.62 billion) and presenteeism (€2.83 billion). Conclusions Obesity is associated with high direct and indirect costs, and cost-effective prevention programmes are deemed
fundamental to contain this public health threat in Italy
Feshbach resonances in ultracold K(39)
We discover several magnetic Feshbach resonances in collisions of ultracold
K(39) atoms, by studying atom losses and molecule formation. Accurate
determination of the magnetic-field resonance locations allows us to optimize a
quantum collision model for potassium isotopes. We employ the model to predict
the magnetic-field dependence of scattering lengths and of near-threshold
molecular levels. Our findings will be useful to plan future experiments on
ultracold potassium atoms and molecules.Comment: 7 pages, 6 figure
Hospital autopsy for prevention of sudden cardiac death
In the past 20 years, cardiovascular mortality has decreased in highincome countries in response to the adoption of preventive measures to reduce the burden of coronary artery disease and heart failure. Despite these encouraging results, cardiovascular diseases are responsible for approximately 17 million deaths every year in the world, approximately 25% of which are sudden cardiac death. The risk of sudden cardiac death is higher in men than in women, and it increases with age due to the higher prevalence of coronary artery disease in older age. Accordingly, the sudden cardiac death rate is estimated to range from 1.40 per 100 000 person-years in women to 6.68 per 100 000 person-years in men. Sudden cardiac death in younger individuals has an estimated incidence of 0.46\u20133.7 events per 100 000 person-years, corresponding to a rough estimate of 1100\u20139000 deaths in Europe and 800\u20136200 deaths in the USA every year.
Cardiac diseases associated with sudden cardiac death differ in young vs. older individuals. In the young there is a predominance of channelopathies and cardiomyopathies, myocarditis and substance abuse, while in older populations, chronic degenerative diseases predominate. In younger persons, the cause of sudden cardiac death may be elusive even after autopsy, because conditions such as inherited channelopathies or drug-induced arrhythmias that are devoid of structural abnormalities are epidemiologically relevant in this age group. Identification of the cause of an unexpected death provides the family with partial understanding and rationalization of the unexpected tragedy, which facilitates the coping process and allows an understanding of whether the risk of sudden death may extend to family members. Accordingly, author present their
experience with autopsies of unexplained sudden death young victims in which a cardiac origin was suspected and the relevance of a standardized protocol for heart examination and histological sampling, as well as for toxicology and molecular investigation
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