625 research outputs found
Exposure to polychlorinated biphenyls and hexachlorobenzene, semen quality and testicular cancer risk
PURPOSE: We carried out a case-control study to investigate the possible role of occupational and environmental exposure to endocrine disruptors in the onset of testicular cancer (TC).
METHODS: We evaluated 125 TC patients and 103 controls. Seminal fluid examination and organochlorine analysis were performed in all subjects. Cases and controls were also interviewed using a structured questionnaire to collect demographic information, residence, andrological medical history and dietary information.
RESULTS: We found that a higher level of reproductive tract birth defects was associated with a higher risk of TC. With regard to diet, cases reported a higher consumption of milk and dairy products than controls. Overall, there was a statistically significant increase in TC risk in cases with detectable values of total polychlorinated organic compounds against controls (14.4 vs. 1.0 %; p < 0.001). TC patients with detectable levels of organochlorines had lower mean semen parameters than those with undetectable levels, although this difference was not statistically significant.
CONCLUSION: The International Agency for Research on Cancer recently included dioxin-like polychlorinated biphenyls (PCBs) in Group 1 of known human carcinogens. Our study confirmed and identified various risk factors for testicular cancer: cryptorchidism, consumption of milk and dairy products, parents' occupation and serum concentration of hexachlorobenzene and PCBs and, for the first time, we showed the correlation between semen quality and the serum concentration of these pollutants
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)
High-speed and high-resolution 2D and 3D elemental imaging of corroded ancient glass by laser ablation-ICP-MS
In this work, laser ablation-inductively coupled plasma-mass spectrometry was used to investigate for the first time glass weathering mechanisms using high-resolution 2D and 3D elemental maps of altered layers of ancient glass. Roman archaeological glass shards, displaying several corrosion indicators, were studied using multiple raster-scanning ablation with high depth and lateral resolution. The concentration gradients of different elements were captured (in their variations from the surface to the bulk of pristine glass) by multiple ablations on degraded regions of interest to observe the dissolution of the glass network due to the hydration and leaching processes that occur during its alteration. The results indicated an enrichment of silicon and a depletion of alkaline/alkaline earth element concentration in the first few microns of depth under the surface area suggesting that a de-alkalinisation phenomenon occurs on the glass surface when ancient items have been buried under soil for extended timeframes. The layer-by-layer elemental distribution revealed also how the composition of the archaeological glass changes from the bulk to the surface, shedding light on the leaching behaviour of glass constituents during the alteration process
Compositional changes by SIMS and XPS analyses on fresh and aged Roman-like glass
This study reports important analytical evidence of an unusual non-uniform element distribution in the superficial layers of glass matrices (from few nm up to 1 µm). The unforeseen observation was made on silica-soda-lime glass mock-ups before and after their artificial ageing, using secondary ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS) surface analysis techniques. The analyses showed a marked non-homogeneous element distribution at the glass surface. The results indicated a very low concentration of Na at the surface up to a depth of around 500 nm below the surface, where its concentration increases reaching a plateau. In addition, the profile distribution of H in the first 200 nm of the pristine glass surface indicated a diffusion of hydrogen from the surrounding environment to the glass network. Additional modifications during the glass ageing process related to external factors (such as temperature and humidity) were also identified in relation to sodium atoms, with atoms on the glass surface showing a different chemical state from those in the bulk. This study confirms that glass composition as well as glass alteration are non-homogeneous locally supporting the importance of studying glass surface as region of interaction with surrounding environment
Comment on a recent sensitivity analysis of radial base function and multi-layer feed-forward neural network models - Response
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b \bar b b\bar b production in proton-nucleus collisions at the LHC
A sizable rate of events, with several pairs of -quarks produced
contemporarily by multiple parton interactions, may be expected at very high
energies as a consequence of the large parton luminosities. The production
rates are further enhanced in hadron-nucleus reactions, which may represent a
convenient tool to study the phenomenon. We compare the different contributions
to production, due to single and double parton
scatterings, in collisions of protons with nuclei at the CERN-LHC.Comment: 13 pages, 4 figure
¿“Nos enfrentamos y nos abrazamos”? Un nuevo recorrido por los usos oficiales del pasado durante el bicentenario de la Revolución de Mayo
El presente trabajo analiza, en primer lugar, los modos en que la historia argentina se tradujo, durante los festejos oficiales del bicentenario de la RevoluciĂłn de Mayo, en artefactos culturales y festivos dirigidos a atraer un pĂşblico vasto, prestando especial atenciĂłn a los usos del pasado allĂ exhibidos. En segundo lugar, pone en relaciĂłn dichas operaciones con las variaciones ocurridas en el nivel de las prácticas polĂticas gubernamentales tras la crisis polĂtica de 2008. En Ăşltima instancia, se plantea que el gobierno de Cristina Fernández de Kirchner se inclinĂł, al momento de proyectar el festejo patrio en cuestiĂłn, por una lĂłgica discursiva liberal–centrada, especialmente, en el consenso inclusivo y la aceptaciĂłn de las diferencias–con el fin de matizar la particiĂłn del espacio socio-polĂtico, exhibir una naciĂłn reconciliada, interpelar a la sociedad argentina en su conjunto y, de ese modo, contribuir a la reconstrucciĂłn de su hegemonĂa polĂtica.Firstly, this paper analyzes how Argentinian history was translated, during the national celebrations of the May Revolution bicentennial, into cultural and festive devices aimed at attracting a massive audience, paying special attention to the uses of the past displayed. Secondly, it illustrates the relations between these operations and the variations of government policy that occurred after the 2008 political crisis. Ultimately, it claims that the Cristina Fernández de Kirchner administration adopted, when it came to planning this national holiday, a liberal discursive logic – mainly characterized by inclusive consensus and pluralism – in order to ease the division of the social and political space, display a reconciled nation, address the entire Argentinean society and, thereby, contribute to the reconstruction of Kirchnerist hegemony.Fil: Amorebieta y Vera, MarĂa Laura. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata. Instituto de Investigaciones en Humanidades y Ciencias Sociales. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la EducaciĂłn. Instituto de Investigaciones en Humanidades y Ciencias Sociales; Argentin
Are nutrition and physical activity associated with gut microbiota? A pilot study on a sample of healthy young adults
BACKGROUND: The literature shows that gut microbiota composition is related with health, and a lot of individual and outer factors may determine its variability. In particular, nutrition and exercise seem to influence the presence in the gut of the two major bacterial phyla of Firmicutes and Bacteroidetes. STUDY DESIGN: An ongoing cross-sectional investigation is aimed to explore these associations in humans. METHODS: Healthy Caucasian young adults were asked to provide a fecal sample in order to analyze their gut microbiome considering their Body Mass Index (BMI), adherence to Mediterranean diet and Physical Activity (PA) level. RESULTS: A total of 59 participants (49.1% males, mean age 23.1 ± 3.14 years) were enrolled so far. Firmicutes (61.6±14.6) and Bacteroidetes (30.7 ± 13.3) showed the highest relative abundance in fecal samples. The Pearson's analysis showed a significant negative correlation between PA and Firmicutes (r =-0.270, p = 0.03). Linear regression confirmed a significant decrease of this phylum with the increase of PA (R2 = 0.07, p = 0.03). CONCLUSIONS: These preliminary results suggest the association between physical activity and gut microbiota composition in healthy humans
Out-of-hospital helmet CPAP in acute respiratory failure reduces mortality: a study led by nurses
Background and Aim. Acute respiratory failure (ARF) is a condition that must be treated as quickly as possible. Continuous Positive Airway Pressure (CPAP) is a common method used to treat ARF in hospital. The main objective of our study was to investigate the effect of CPAP prior to admission to the emergency room, on the reduction of endotracheal intubation, in-hospital mortality and on the length of stay in hospital (HLOS). Methods. A prospective, observational (non-randomised) study with a historical control group. Data from 3 groups of patients with ARF, irrespective of cause, was collected: pre-hospital CPAP (PHCPAP) group, i.e. 35 patients treated with a helmet CPAP in the ambulance, by trained nurses (mean age, years 80.1±7.9 SD; 14 males); hospital CPAP (HCPAP) group, i.e. 46 patients treated with helmet CPAP in the hospital emergency room (mean age 78.6±6.9 SD; 27 males), and a historical control group of 125 patients treated with medical therapy only (mean age 76.7±5.5 SD; 52 males). CPAP was delivered via a helmet interface. Results. Compared with standard medical therapy, helmet CPAP (pre and in-hospital) reduced mortality by 77 % (p=0.005), while pre-hospital helmet CPAP reduced it by 94% (p=0.011), after adjustment for age, sex, severity of clinical conditions at entry and diagnosis upon admission. HLOS was reduced, compared with standard medical therapy, by 63.5% and by 66% (adjusting for age, sex, severity of clinical conditions at entry and diagnosis at admission) with helmet CPAP (pre and in-hospital) and with helmet CPAP in the ambulance, respectively (p<0.0001). Conclusions. Treating patients with ARF of any cause, with CPAP by trained nurses, before hospital admission, is safe, reduces mortality and the length of stay needed in hospital
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