Are the school prevention programmes - aimed at de-normalizing smoking among youths - beneficial in the long term? An example from the Smoke Free Class Competition in Italy

Tobacco smoking by young people is of great concern because it usually leads to regular smoking, nicotine addiction and quitting difficulties. Young people "hooked" by tobacco maintain the profits of the tobacco industry by replacing smokers who quit or die. If new generations could be tobacco-free, as supported by tobacco endgame strategies, the tobacco epidemic could end within decades. Smoking prevention programmes for teens are offered by schools with the aim to prevent or delay smoking onset. Among these, the Smoke Free Class Competition (SFC) was widely implemented in Europe. Its effectiveness yielded conflicting results, but it was only evaluated at short/medium term (6 - 18 months). The aim of this study is to evaluate its effectiveness after a longer follow-up (3 to 5 years) in order to allow enough time for the maturing of the students and the internalization of the experience and its contents. Fifteen classes were randomly sampled from two Italian high schools of Bologna province that regularly offered the SFC to first year students; 382 students (174 participating in the SFC and 208 controls) were retrospectively followed-up and provided their "smoking histories". At the end of their last year of school (after 5 years from the SFC), the percentage of students who stated that they were regular smokers was lower among the SFC students than in controls: 13.5% vs 32.9% (p=0.03). From the students' "smoking histories", statistically significant protective ORs were observed for SFC students at the end of 1st and 5th year: 0.42 (95% CI 0.19-0.93) and 0.32 (95% CI 0.11-0.91) respectively. Absence of smokers in the family was also a strongly statistically significant factor associated with being a non-smoker student. These results suggest that SFC may have a positive impact on lowering the prevalence of smoking in the long term (5 years)

The origin of ultra high energy cosmic rays

We briefly discuss some open problems and recent developments in the investigation of the origin and propagation of ultra high energy cosmic rays (UHECRs).Comment: Invited Review Talk at TAUP 2005 (Zaragoza - September 10-14, 2005). 7 page

Numerical propagation of high energy cosmic rays in the Galaxy I: technical issues

We present the results of a numerical simulation of propagation of cosmic rays with energy above $10^{15}$ eV in a complex magnetic field, made in general of a large scale component and a turbulent component. Several configurations are investigated that may represent specific aspects of a realistic magnetic field of the Galaxy, though the main purpose of this investigation is not to achieve a realistic description of the propagation in the Galaxy, but rather to assess the role of several effects that define the complex problem of propagation. Our simulations of Cosmic Rays in the Galaxy will be presented in Paper II. We identified several effects that are difficult to interpret in a purely diffusive approach and that play a crucial role in the propagation of cosmic rays in the complex magnetic field of the Galaxy. We discuss at length the problem of the extrapolation of our results to much lower energies where data are available on the confinement time of cosmic rays in the Galaxy. The confinement time and its dependence on particles' rigidity are crucial ingredients for 1) relating the source spectrum to the observed cosmic ray spectrum; 2) quantifying the production of light elements by spallation; 3) predicting the anisotropy as a function of energy.Comment: 29 pages, 12 figures, submitted to JCA

Generalized Bayesian Record Linkage and Regression with Exact Error Propagation

Record linkage (de-duplication or entity resolution) is the process of merging noisy databases to remove duplicate entities. While record linkage removes duplicate entities from such databases, the downstream task is any inferential, predictive, or post-linkage task on the linked data. One goal of the downstream task is obtaining a larger reference data set, allowing one to perform more accurate statistical analyses. In addition, there is inherent record linkage uncertainty passed to the downstream task. Motivated by the above, we propose a generalized Bayesian record linkage method and consider multiple regression analysis as the downstream task. Records are linked via a random partition model, which allows for a wide class to be considered. In addition, we jointly model the record linkage and downstream task, which allows one to account for the record linkage uncertainty exactly. Moreover, one is able to generate a feedback propagation mechanism of the information from the proposed Bayesian record linkage model into the downstream task. This feedback effect is essential to eliminate potential biases that can jeopardize resulting downstream task. We apply our methodology to multiple linear regression, and illustrate empirically that the "feedback effect" is able to improve the performance of record linkage.Comment: 18 pages, 5 figure

Observables in Topological Yang-Mills Theories

Using topological Yang-Mills theory as example, we discuss the definition and determination of observables in topological field theories (of Witten-type) within the superspace formulation proposed by Horne. This approach to the equivariant cohomology leads to a set of bi-descent equations involving the BRST and supersymmetry operators as well as the exterior derivative. This allows us to determine superspace expressions for all observables, and thereby to recover the Donaldson-Witten polynomials when choosing a Wess-Zumino-type gauge.Comment: 39 pages, Late

Total Gastrectomy for locally advanced Cancer: The total Laparoscopic Approach

Total gastrectomy is the treatment of choice for adenocarcinoma of the upper and middle third of the stomach resected with curative intent. The laparoscopic approach allows satisfactory exploration of the peritoneal cavity and optimizes staging in borderline T3 or T4 tumours in patients affected by locally advanced tumours or intraperitoneal carcinomatosis. Laparoscopy can eliminate unnecessary laparotomies in 10 % of patients affected by these conditions with formal contraindications for resection [1] . Complete resection of the stomach associated with D2 lymph node dissection is also performed using a currently well-established technique [2, 3] . The specificity of laparoscopic gastric resection for cancer is that the stomach and the greatomentum are withdrawn separately.Reconstruction of the digestive tract is more complex, and requires a variety of techniques (supra-umbilical mini-laparotomy, Orvil® technique, enlarging a port-site for passage of a circular stapler, mechanical side to side anastomosis, etc), but none ofthese has become the gold standard [4-7] . This explains the difficulties encountered in promoting the widespread use of minimally invasive resection in western countries. Scientific societies insist on the need for prospective studies to establish the place of laparoscopy for gastric cancer (prophylactic gastrectomy for CDH-1 related gastric cancer, < T3 Tumours, palliative gastrectomy) [4] . Here, we present our technique for total resection of the stomach and D2 lymph node dissection, which allows the manualcreation of a feasible, safe, tension-free and effective esojejunal anastomosis. It can be performed by any surgeon familiar with laparoscopic surgery and the principles of oncologic resection. The cost is also relatively low because neither a circular staplernor other special equipment is required. Finally, the incision for extraction of the specimen can be placed in any area of the abdomen (usually through a supra-pubic incision in our practice).Keywords: Gastric cancer, laparoscopy, total gastrectomy, lymphadenectomy, Intracorporeal anastomosis.Total gastrectomy is the treatment of choice for adenocarcinoma of the upper and middle third of the stomach resected with curative intent. The laparoscopic approach allows satisfactory exploration of the peritoneal cavity and optimizes staging in borderline T3 or T4 tumours in patients affected by locally advanced tumours or intraperitoneal carcinomatosis. Laparoscopy can eliminate unnecessary laparotomies in 10 % of patients affected by these conditions with formal contraindications for resection [1] . Complete resection of the stomach associated with D2 lymph node dissection is also performed using a currently well-established technique [2, 3] . The specificity of laparoscopic gastric resection for cancer is that the stomach and the great omentum are withdrawn separately.Reconstruction of the digestive tract is more complex, and requires a variety of techniques (supra-umbilical mini-laparotomy, Orvil® technique, enlarging a port-site for passage of a circular stapler, mechanical side to side anastomosis, etc), but none of these has become the gold standard [4-7] . This explains the difficulties encountered in promoting the widespread use of minimally invasive resection in western countries. Scientific societies insist on the need for prospective studies to establish the place of laparoscopy for gastric cancer (prophylactic gastrectomy for CDH-1 related gastric cancer, < T3 Tumours, palliative gastrectomy) [4] . Here, we present our technique for total resection of the stomach and D2 lymph node dissection, which allows the manual creation of a feasible, safe, tension-free and effective esojejunal anastomosis. It can be performed by any surgeon familiar with laparoscopic surgery and the principles of oncologic resection. The cost is also relatively low because neither a circular stapler nor other special equipment is required. Finally, the incision for extraction of the specimen can be placed in any area of the abdomen (usually through a supra-pubic incision in our practice).Keywords: Gastric cancer, laparoscopy, total gastrectomy, lymphadenectomy, Intracorporeal anastomosis

Stochastic conversions of TeV photons into axion-like particles in extragalactic magnetic fields

Very-high energy photons emitted by distant cosmic sources are absorbed on the extragalactic background light (EBL) during their propagation. This effect can be characterized in terms of a photon transfer function at Earth. The presence of extragalactic magnetic fields could also induce conversions between very high-energy photons and hypothetical axion-like particles (ALPs). The turbulent structure of the extragalactic magnetic fields would produce a stochastic behaviour in these conversions, leading to a statistical distribution of the photon transfer functions for the different realizations of the random magnetic fields. To characterize this effect, we derive new equations to calculate the mean and the variance of this distribution. We find that, in presence of ALP conversions, the photon transfer functions on different lines of sight could have relevant deviations with respect to the mean value, producing both an enhancement or a suppression in the observable photon flux with respect to the expectations with only absorption. As a consequence, the most striking signature of the mixing with ALPs would be a reconstructed EBL density from TeV photon observations which appears to vary over different directions of the sky: consistent with standard expectations in some regions, but inconsistent in others.Comment: v2: 22 pages, 5 eps figures. Minor changes. A reference added. Matches the version published on JCA

Experimental determination of the J(pi) components of the spin-dipole resonance in B-12

AbstractThe inclusive C12(d→,He2) and exclusive C12(d→,He2+n) reactions have been studied with a beam energy of 171 MeV and scattering angles for the (d,He2) reaction θ=0° and 3°. The studies focused on the separation of the isovector spin-dipole resonance (IVSGDR) into its components by measuring tensor-analysing powers and observing the direct neutron decay to the low-lying proton-hole states in 11B. Merging the information obtained from both measurements resulted in the first-time verification of model-independent predictions of tensor-analysing powers at extreme forward angles and the experimental decomposition of the IVSGDR into its Jπ components. The experimental results are in reasonable agreement with theoretical estimates based on shell-model calculations

Fast Liquid Chromatography Coupled with Tandem Mass Spectrometry for the Analysis of Vanillic and Syringic Acids in Ice Cores

The development of new analytical systems and the improvement of the existing ones to obtain high-resolution measurements of chemical markers in samples from ice cores, is one of the main challenges the paleoclimatic scientific community is facing. Different chemical species can be used as markers for tracking emission sources or specific environmental processes. Although some markers, such as methane sulfonic acid (a proxy of marine productivity), are commonly used, there is a lack of data on other organic tracers in ice cores, making their continuous analysis analytically challenging. Here, we present an innovative combination of fast liquid chromatography coupled with tandem mass spectrometry (FLC-MS/MS) to continuously determine organic markers in ice cores. After specific optimization, this approach was applied to the quantification of vanillic and syringic acids, two specific markers for biomass burning. Using the validated method, detection limits of 3.6 and 4.6 pg mL-1for vanillic and syringic acids, respectively, were achieved. Thanks to the coupling of FLC-MS/MS with the continuous flow analytical system, we obtained one measurement every 30 s, which corresponds to a sampling resolution of a sample every 1.5 cm with a melting rate of 3.0 cm min-1. To check the robustness of the method, we analyzed two parallel sticks of an alpine ice core over more than 5 h. Vanillic acid was found with concentrations in the range of picograms per milliliter, suggesting the combustion of coniferous trees, which are found throughout the Italian Alps

High Energy Neutrinos From Superheavy Dark Matter Annihilation

Superheavy ($M>10^{10}$ GeV) particles produced during inflation may be the dark matter, independent of their interaction strength. Strongly interacting superheavy particles will be captured by the sun, and their annihilation in the center of the sun will produce a flux of energetic neutrinos that should be detectable by neutrino telescopes. Depending on the particle mass, event rates in a cubic-kilometer detector range from several per hour to several per year. The signature of the process is a predominance of tau neutrinos, with a relatively flat energy spectrum of events ranging from 50 GeV to many TeV, and with the mean energy of detected tau neutrinos about 3 TeV.Comment: 24 pages, 7 figure