519 research outputs found
Non-Binary Message-Passing Algorithms for Magnetic Channels with Data-Dependent Noise
The paper proposes an implementation of the message
passing algorithm adapted to iterative channel detection.
The algorithm uses soft messages associated to non binary
symbols in order to cancel cycles in the equivalent Tanner graphs,
achieving optimal performance after a low number of iterations.
This architecture, suited to very fast channel detectors, is applied
to magnetic recording channels and adapted to the non stationary
nature of the magnetic media noise
Steel slag as a low-impact filler in rubber compounds for environmental sustainability
This study investigates the use of electric arc furnace (EAF) slag, as a substitute for conventional filler, such as calcium carbonate, in nitrile-butadiene rubber (NBR) composites in different volume fraction. The results demonstrate that slag exhibits morphological traits comparable to calcium carbonate when used as a filler, moreover their processability and mechanical properties are similar. Specifically, at 20% v/v, slag-flled NBR exhibits slightly longer scorch times but unchanged vulcanization times. Both fillers at 20% v/v show comparable hardness, compression strength, and elastic modulus. Tensile properties are also comparable, except for the strain at break, where slag-filled NBR shows a 40% higher tensile strain at break. The environmental impact of this innovative slag application has been evaluated through a comparative life cycle assessment. All assessed impact categories demonstrate a reduction of at least 89%. The study suggests that the use of EAF slag has the potential to promote sustainable waste management
Fracture assessment of polyamide 12 (PA12) specimens fabricated via Multi Jet FusionTM in the presence of geometrical discontinuities
This study aims to study the fracture resistance of additively manufactured polyamide 12 (PA12), specifically when subjected to notches and cracks, and how it varies with the printing direction using Multi Jet Fusion (MJF). The methodology involved conducting tensile tests on V-notched samples, with a focus on different combinations of opening angle (0◦-120◦) and tip radius (0.2–2 mm). The findings revealed that the sensitivity to the notch opening angle decreased with an increase in the notch tip radius. Furthermore, the fracture resistance for different mode mixities was examined using semi-circular bend (SCB) specimens, with the crack angle varied between 0◦ and 53◦. The results demonstrated two distinct fracture behaviours, namely brittle and ductile,
depending on the crack angle. Theoretical analyses revealed that with appropriate tuning,
average strain energy density (ASED) can predict the load capacity of notched and cracked PA12 parts manufactured with MJF, within an error range of ± 20 %
The nature and evolution of Nova Cygni 2006
AIMS: Nova Cyg 2006 has been intensively observed throughout its full
outburst. We investigate the energetics and evolution of the central source and
of the expanding ejecta, their chemical abundances and ionization structure,
and the formation of dust. METHOD: We recorded low, medium, and/or
high-resolution spectra (calibrated into accurate absolute fluxes) on 39
nights, along with 2353 photometric UBVRcIc measures on 313 nights, and
complemented them with IR data from the literature. RESULTS: The nova displayed
initially the normal photometric and spectroscopic evolution of a fast nova of
the FeII-type. Pre-maximum, principal, diffuse-enhanced, and Orion absorption
systems developed in a normal way. After the initial outburst, the nova
progressively slowed its fading pace until the decline reversed and a second
maximum was reached (eight months later), accompanied by large spectroscopic
changes. Following the rapid decline from second maximum, the nova finally
entered the nebular phase and formed optically thin dust. We computed the
amount of formed dust and performed a photo-ionization analysis of the
emission-line spectrum during the nebular phase, which showed a strong
enrichment of the ejecta in nitrogen and oxygen, and none in neon, in agreement
with theoretical predictions for the estimated 1.0 Msun white dwarf in Nova Cyg
2006. The similarities with the poorly investigated V1493 Nova Aql 1999a are
discussed.Comment: in press in Astronomy and Astrophysic
Use of water in the Iberoamérican dry lands: hydro-environmental and socioeconomic efficiency indicators
Uso del agua en tierras secas de Iberoamérica: indicadores de eficiencia hidro-ambiental y socio-económica. Las tierras secas comprenden una superficie sustancial de Iberoamérica (25% de América Latina y el Caribe, o más de la mitad del estado español). En este contexto, Brasil posee una porción significativa de los recursos hídricos superficiales y subterráneos. Sin embargo, en su territorio se encuentran áreas semi-áridas, con extrema escasez hídrica, que comprenden 1300 municipios (cerca del 25% del total de municipios del país), distribuidos en 9 estados, en los que viven más de 22,5 millones de habitantes. Estos se encuentran afectados directa o indirectamente por una situación de severa escasez de recursos hídricos agravada por cambios climáticos, consecuencia del calentamiento global. Resulta importante conocer el acervo de tecnologías tradicionales y no tradicionales para captar, almacenar, y utilizar el agua, adaptadas a las diferentes situaciones socio-económicas e hidro-ambientales, así como indicadores del uso eficiente del agua, validados y homologados como herramienta estratégica de gestión en políticas y programas de seguridad hídrica. Este trabajo tiene como objetivo conocer el estado de nuestro conocimiento sobre dichos indicadores y discutir el caso del semi-árido brasileño en el contexto de las tierras secas de Iberoamérica, y del Plan Nacional de Recursos Hídricos del Estado de Bahía.The dry lands cover expressive surface of Iberoamerican (25% of Latin American and Caribbean and more than half of the Spanish territory). In this context, Brazil is a country that possesses significant volume of the world superficial and underground water resources. However, more than 1300 municipal districts (about 25% of the total of municipal districts of the country), distributed in 9 states are directly or indirectly affected by extreme shortage of water resources which has been worsened by the climatic changes, as a consequence of the global warming. More than 22.5 million inhabitants live in the semi-arid areas of Brazil. It is important to scrutiny all traditional and not traditional technologies for reception, storage and use of the water, adapted for different socioeconomic and hydro-environmental situations and approve and validate indicators of water use efficiency, as a management strategic tool for water security politics and programs. This work aimed to understand the state of the art on indicators and to discuss the Brazilian case of the semi-arid in the context of the Iberoamerican dry lands, based on the National Plan of Water Resources and on the State of Bahia Plan for Water Resource Management.Fil: Carneiro, A. P.. Universidad Politécnica de Catalunya; EspañaFil: da Silva, H. P.. Universidade Federal da Bahia; BrasilFil: Abraham, Elena Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Morató, J.. No especifíca;Fil: Subirana, A.. Universidad Politécnica de Catalunya; EspañaFil: Tomasoni, M.. Universidade Federal da Bahia; Brasi
Relationship between the prevalence of Dibothriocephalus latus(Cestoda: Diphyllobothriidea) and the load of Escherichia coli: New findings in a neglected fish-borne parasitic zoonosis
The sub-Alpine lakes of Switzerland, Italy and France have long been reported as an endemic area of diphyllobothriosis, a parasitic zoonosis aused by Dibothriocephalus latus. With this study, we explored the hypothesis for a relationship between the prevalence of D. latus in Perca fluviatilis and the Escherichia coli load in lake water. To do this, we identified eleven sampling sites in three areas (north, centre and south) of Lake Iseo (north Italy) to determine E. coli load and the prevalence of D. latus in P. fluviatilis. Prevalence and 95% confidence interval (CI) of D. latus infestation ranged from 0% (95% CI: 0.71–0.0) in Sarnico (southern area) to 20% (95% CI: 33.0–11.2) in Pisogne (northern area). There were significant differences in prevalence be-tween the sites (χ2= 31.12; p- value= .0006) and in E. coli load (Kruskal–Wallis test; p- value= .0005). There was decreasing gradient of E. coli load and prevalence of D. latus infestation from north to south. A significant positive correlation (r= .881; p- value= .003) was found between E. coli load and prevalence of D. latus. Also, linear regression showed a significant relationship between E. coli load and prevalence of infestation (R2= .775). Our findings offer an explanation for the link between E. coliload in water and D. latus prevalence. The potential factors in this link are the ef-ficiency of the local wastewater treatment plant, the bathymetric profile of the lake and the life cycle of D. latus, which is mainly affected by light and water temperature.KEYWORDSItaly, Lake Iseo, Perca fluviatilis, prevalence of infestation, wastewater treatment plant, the bathymetric profile of the lake and the life cycle of D. latus, which is mainly affected by light and water temperature
Miscarriage following dengue virus 3 infection in the first six weeks of pregnancy of a dengue virus-naive traveller returning from Bali to Italy, April 2016
We report miscarriage following dengue virus (DENV)-3 infection in a pregnant woman returning from Bali to Italy in April 2016. On her arrival, the woman had fever, rash, asthenia and headache. DENV RNA was detected in plasma and urine samples collected the following day. Six days after symptom onset, she had a miscarriage. DENV RNA was detected in fetal material, but in utero fetal infection cannot be demonstrated due to possible contamination by maternal blood
EUS-guided drainage using lumen apposing metal stent and percutaneous endoscopic necrosectomy as dual approach for the management of complex walled-off necrosis: a case report and a review of the literature
Background: Endoscopic ultrasound-guided drainage is suggested as the first approach in the management of symptomatic and complex walled-off pancreatic necrosis. Dual approach with percutaneous drainage could be the best choice when the necrosis is deep extended till the pelvic paracolic gutter; however, the available catheter could not be large enough to drain solid necrosis neither to perform necrosectomy, entailing a higher need for surgery. Therefore, percutaneous endoscopic necrosectomy through a large bore percutaneous self-expandable metal stent has been proposed. Case presentation: In this study, we present the case of a 61-year-old man admitted to our hospital with a history of sepsis and persistent multiorgan failure secondary to walled-off pancreatic necrosis due to acute necrotizing pancreatitis. Firstly, the patient underwent transgastric endoscopic ultrasound-guided drainage using a lumen-apposing metal stent and three sessions of direct endoscopic necrosectomy. Because of recurrence of multiorgan failure and the presence of the necrosis deeper to the pelvic paracolic gutter at computed tomography scan, we decided to perform percutaneous endoscopic necrosectomy using an esophageal self-expandable metal stent. After four sessions of necrosectomy, the collection was resolved without complications. Therefore, we perform a revision of the literature, in order to provide the state-of-art on this technique. The available data are, to date, derived by case reports and case series, which showed high rates both of technical and clinical success. However, a not negligible rate of adverse events has been reported, mainly represented by fistulas and abdominal pain. Conclusion: Dual approach, using lumen apposing metal stent and percutaneous self-expandable metal stent, is a compelling option of treatment for patients affected by symptomatic, complex walled-off pancreatic necrosis, allowing to directly remove large amounts of necrosis avoiding surgery. Percutaneous endoscopic necrosectomy seems a promising technique that could be part of the step-up-approach, before emergency surgery. However, to date, it should be reserved in referral centers, where a multidisciplinary team is disposable
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