2,276 research outputs found
Opiniones, prácticas, barreras y predisposición al cambio, a la hora de dar consejo para dejar de fumar
ObjetivoConocer las opiniones, las prácticas actuales, las barreras percibidas y la predisposición al cambio con respecto al consejo para dejar de fumar (CF) ofertado a los pacientes por los diferentes profesionales sanitarios (PS) de atención primaria.DiseñoEstudio descriptivo, transversal.EmplazamientoCentros de salud del Área Sanitaria 9, de Madrid.ParticipantesParticiparon 480 PS, entre médicos de familia, pediatras, residentes de medicina familiar y comunitaria, y enfermería.MedicionesMediante cuestionario autocumplimentado y anónimo se recogen variables sociodemográficas, sobre actitudes, creencias y utilización de estrategias en CF y sobre barreras percibidas para darlo, así como la predisposición al cambio.ResultadosContestó al cuestionario el 75,2% (el 94,2, 61,1, 51,6 y 88% de los médicos, enfermeros, pediatras y residentes, respectivamente). El 72% pregunta de manera habitual, con un incremento hasta el 92,4% en las enfermedades relacionadas con el tabaquismo, sin diferencias respecto al sexo, el PS, el hábito tabáquico y la formación previa. El 85,8% ofrece realizar un seguimiento y el 63,5% proporciona consejos escritos. El 75% de los no fumadores se considera modelo social, frente al 40% de los fumadores. Las principales barreras son la falta de tiempo y la baja motivación en los pacientes. El 93,5% cree que es necesaria una formación específica para proporcionar CF.ConclusionesSe pregunta y se ofrece CF, independientemente del hábito tabáquico del PS. A pesar de las barreras, hay una adecuada utilización de las estrategias para proporcionar CF. Hay buena predisposición al cambio para optimizar el CF.ObjectiveTo get to know the opinions, current practices, perceived barriers and stage of change in respect to the smoking cessation advice (SCA) offered to patients by the different health professionals (HP) from primary care.DesignDescriptive cross-sectional study.LocationÁrea Sanitaria 9’s Health Centers, inMadrid, Spain.Participants480 HPs, including primary care doctors, pediatricians, primary care residents, and nursery staff.MeasurementsUsing a self-filled and anonymous questionnaire, we will gather sociodemographic variables and from the HP’s office, regarding the attitudes towards tobacco, efficiency beliefs and use of strategies in the advice, and the perceived barriers to give it, as well as the state of change.Results75.2% of the HPs filled the questionnaire (94.2%, 61.1%, 51.6%, and 88% by doctors, nurses, pediatricians, and residents respectively). 72% ask regularly, this rate increasing to 92.4% over tobacco-related diseases. No differences were made between sexes, professional types, tobacco habits, or previous attendance to courses. 85.8% offers tracing and 63.5% give written advices. Nearly 75% of non-smokers are considered social role models, that against only 40% of smokers. The main barriers found were lack of time and low motivation from the patients. 93.5% consider an specific education necessary to give efficient SCA.ConclusionsInquiries are made and SCA is given, independently of the smoking habits of the SCA. Likewise, there is a good state of change by the HPs to optimize the treatment of tobacco dependency
LES Eulerian diffuse-interface modeling of fuel dense sprays near- and far-field
[EN] Engine fuel spray modeling still remains a challenge, especially in the dense near-nozzle region. This region is difficult to experimentally access and also to model due to the complex and rapid liquid and gas interaction. Modeling approaches based on Lagrangian particle tracking have failed in this area, while Eulerian modeling has proven to be particularly useful. Interface resolved methods are still limited to primary atomization academic configurations due to excessive computational requirements. To overcome those limitations, the single-fluid diffuse interface model known as Sigma-Y, arises as a single-framework for spray simulations. Under the assumption of scale separation at high Reynolds and Weber numbers, liquid dispersion is modeled as turbulent mixing of a variable density flow. The concept of surface area density is used for representing liquid structures, regardless of the complexity of the interface.
In this work, a LES based implementation of the Sigma-Y model in the OpenFOAM CFD library is applied to simulate the ECN Spray A configuration. Model assessment is performed for both near- and far-field spray development regions using different experimental diagnostics available from ECN database. The CFD model is able to capture near-nozzle fuel mass distribution and, after Sigma equation constant calibration, interfacial surface area. Accurate predictions of spray far-field evolution in terms of liquid and vapor tip penetration and local velocity can be simultaneously achieved. Model accuracy is lower when compared to mixture fraction axial evolution, despite radial distribution profiles are well captured.This work was partially funded by the Spanish Ministerio de Economia y Competitividad within the frame of the CHEST (TRA2017-89139-C2-1-R) project. The computations were partially performed on the Tirant III cluster of the Servei d'Informatica of the University of Valencia (vlc38-FI-2018-2-0006). Authors acknowledge the computer resources at Picasso and the technical support provided by Universidad de Malaga (UMA) (RES-FI-2018-1-0039).Desantes Fernández, JM.; García-Oliver, JM.; Pastor Enguídanos, JM.; Olmeda-Ramiro, I.; Pandal, A.; Naud, B. (2020). LES Eulerian diffuse-interface modeling of fuel dense sprays near- and far-field. International Journal of Multiphase Flow. 127:1-13. https://doi.org/10.1016/j.ijmultiphaseflow.2020.103272S113127Andreini, A., Bianchini, C., Puggelli, S., & Demoulin, F. X. (2016). Development of a turbulent liquid flux model for Eulerian–Eulerian multiphase flow simulations. International Journal of Multiphase Flow, 81, 88-103. doi:10.1016/j.ijmultiphaseflow.2016.02.003Anez, J., Ahmed, A., Hecht, N., Duret, B., Reveillon, J., & Demoulin, F. X. (2019). 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Impact of biodiesel fuel on cold starting of automotive direct injection diesel engines
The use of biodiesel fuels in diesel engines is gaining attention as a promising solution to control CO2
emissions. Great research efforts have been carried out to identify the impact of biodiesel physical and
chemical properties on engine systems and processes. Most of these investigations were performed in
warm conditions, but the suitability of biodiesel for starting the engine at under-zero ambient temperatures
has not widely evaluated. The surface tension and the viscosity of biodiesel fuels are higher
compared to those of standard diesel and, in cold conditions, these differences become critical since the
injection fuel rate is largely affected and consequently the combustion process can be deteriorated. In
order to improve its flow characteristics at cold temperatures and make them more suitable for low
temperatures operation, additives are used in biodiesel fuels. In this paper the suitability of different
biodiesel fuels, with and without additives, for cold starting of DI (direct injection) diesel engines has
been evaluated. The results have shown that the engine start-ability with pure biodiesel fuels can be
largely deteriorated. However, using diesel/biodiesel blends the start-ability of the engine can be
recovered with the additional benefit of reducing the opacity peak of the exhaust gasesBroatch Jacobi, JA.; Tormos Martínez, BV.; Olmeda González, PC.; Novella Rosa, R. (2014). Impact of biodiesel fuel on cold starting of automotive direct injection diesel engines. Energy. 73:653-660. doi:10.1016/j.energy.2014.06.062S6536607
Are osteoporotic fractures being adequately investigated?: A questionnaire of GP & orthopaedic surgeons
BACKGROUND: To investigate the current practice of Orthopaedic Surgeons & General Practitioners (GP) when presented with patients who have a fracture, with possible underlying Osteoporosis. METHODS: Questionnaires were sent to 140 GPs and 140 Orthopaedic Surgeons. The participants were asked their routine clinical practice with regard to investigation of underlying osteoporosis in 3 clinical scenarios. 55 year old lady with a low trauma Colles fracture 60 year old lady with a vertebral wedge fracture 70 year old lady with a low trauma neck of femur fracture. RESULTS: Most doctors agreed that patients over 50 years old with low trauma fractures required investigation for osteoporosis, however, most surgeons (56%, n = 66) would discharge patients with low trauma Colles fracture without requesting or initiating investigation for osteoporosis. Most GPs (67%, n = 76) would not investigate a similar patient for osteoporosis, unless prompted by the Orthopaedic Surgeon or patient. More surgeons (71%, n= 83) and GPs (64%, n = 72) would initiate investigations for osteoporosis in a vertebral wedge fracture, but few surgeons (35%, n = 23) would investigate a neck of femur fracture patient after orthopaedic treatment. CONCLUSION: Most doctors know that fragility fractures in patients over 50 years old require investigation for Osteoporosis; however, a large population of patients with osteoporotic fractures are not being given the advantages of secondary prevention
Retention and diffusion of radioactive and toxic species on cementitious systems: Main outcome of the CEBAMA project
Cement-based materials are key components in radioactive waste repository barrier systems. To improve the available knowledge base, the European CEBAMA (Cement-based materials) project aimed to provide insight on general processes and phenomena that can be easily transferred to different applications. A bottom up approach was used to study radionuclide retention by cementitious materials, encompassing both individual cement mineral phases and hardened cement pastes. Solubility experiments were conducted with Be, Mo and Se under high pH conditions to provide realistic solubility limits and radionuclide speciation schemes as a prerequisite for meaningful adsorption studies. A number of retention mechanisms were addressed including adsorption, solid solution formation and precipitation of radionuclides within new solid phases formed during cement hydration and evolution. Sorption/desorption experiments were carried out on several anionic radionuclides and/or toxic elements which have received less attention to date, namely: Be, Mo, Tc, I, Se, Cl, Ra and 14C. Solid solution formation between radionuclides in a range of oxidation states (Se, I and Mo) with the main aqueous components (OH−, SO4 −2, Cl−) of cementitious systems on AFm phases were also investigated
Impact of Daily Thermocycles on Hatching Rhythms, Larval Performance and Sex Differentiation of Zebrafish
In the wild, water temperature cycles daily: it warms up after sunrise, and cools rapidly after sunset. Surprisingly, the impact of such daily thermocycles during the early development of fish remains neglected. We investigated the influence of constant vs daily thermocycles in zebrafish, from embryo development to sexual differentiation, by applying four temperature regimens: two constant (24°C and 28°C) and two daily thermocycles: 28:24°C, TC (thermophase coinciding with daytime, and cryophase coinciding with night-time) and 24:28°C, CT (opposite to TC) in a 12:12 h light:dark cycle (LD). Embryo development was temperature-dependent but enhanced at 28°C and TC. Hatching rhythms were diurnal (around 4 h after lights on), but temperature- and cycle-sensitive, since hatching occurred sooner at 28°C (48 hours post fertilization; hpf) while it was delayed at 24°C (96 hpf). Under TC, hatching occurred at 72 hpf, while under CT hatching displayed two peaks (at 70 hpf and 94 hpf). In constant light (LL) or darkness (DD), hatching rhythms persisted with tau close to 24 h, suggesting a clock-controlled "gating" mechanism. Under 28°C or TC, larvae showed the best performance (high growth and survival, and low malformations). The sex ratio was strongly influenced by temperature, as the proportion of females was higher in CT and TC (79 and 83% respectively), contrasting with 28°C and 24°C, which led to more males (83 and 76%). Ovarian aromatase (cyp19a) expression in females was highest in TC and CT (6.5 and 4.6 fold higher than at 28°C, respectively); while anti-müllerian hormone (amh) expression in males increased in testis at 24°C (3.6 fold higher compared to TC) and particularly at 28°C (14.3 fold increase). Taken together, these findings highlight the key role of environmental cycles during early development, which shaped the daily rhythms in fish embryo and larvae, and ultimately influenced sex differentiation
Hippobosca longipennis - a potential intermediate host of a species of Acanthocheilonema in dogs in northern India
Background
Hippobosca longipennis (the 'dog louse fly') is a blood sucking ectoparasite found on wild carnivores such as cheetahs and lions and domesticated and feral dogs in Africa, the Middle East and Asia, including China. Known as an intermediate host for Acanthocheilonema dracunculoides and a transport host for Cheyletiella yasguri, it has also been suggested that H. longipennis may be a vector for other pathogens, including Acanthocheilonema sp.? nov., which was recently reported to infect up to 48% of dogs in northern India where this species of fly is known to commonly infest dogs. To test this hypothesis, hippoboscid flies feeding on dogs in Ladakh in northern India were collected and subjected to microscopic dissection.
Results
A total of 12 infective larvae were found in 10 out of 65 flies dissected; 9 from the head, 2 from the thorax and 1 from the abdomen. The larvae averaged 2, 900 (± 60) μm in length and 34 (± 5) μm in width and possessed morphological features characteristic of the family Onchocercidae. Genetic analysis and comparison of the 18S, ITS-2, 12S and cox-1 genes confirmed the identity of the larvae as the Acanthocheilonema sp.? nov. reported in dogs in Ladakh.
Conclusion
This study provides evidence for a potential intermediate host-parasite relationship between H. longipennis and the canine Acanthocheilonema sp.? nov. in northern India
Combined search for the quarks of a sequential fourth generation
Results are presented from a search for a fourth generation of quarks
produced singly or in pairs in a data set corresponding to an integrated
luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in
2011. A novel strategy has been developed for a combined search for quarks of
the up and down type in decay channels with at least one isolated muon or
electron. Limits on the mass of the fourth-generation quarks and the relevant
Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a
simple extension of the standard model with a sequential fourth generation of
fermions. The existence of mass-degenerate fourth-generation quarks with masses
below 685 GeV is excluded at 95% confidence level for minimal off-diagonal
mixing between the third- and the fourth-generation quarks. With a mass
difference of 25 GeV between the quark masses, the obtained limit on the masses
of the fourth-generation quarks shifts by about +/- 20 GeV. These results
significantly reduce the allowed parameter space for a fourth generation of
fermions.Comment: Replaced with published version. Added journal reference and DO
Measurement of the t t-bar production cross section in the dilepton channel in pp collisions at sqrt(s) = 7 TeV
The t t-bar production cross section (sigma[t t-bar]) is measured in
proton-proton collisions at sqrt(s) = 7 TeV in data collected by the CMS
experiment, corresponding to an integrated luminosity of 2.3 inverse
femtobarns. The measurement is performed in events with two leptons (electrons
or muons) in the final state, at least two jets identified as jets originating
from b quarks, and the presence of an imbalance in transverse momentum. The
measured value of sigma[t t-bar] for a top-quark mass of 172.5 GeV is 161.9 +/-
2.5 (stat.) +5.1/-5.0 (syst.) +/- 3.6(lumi.) pb, consistent with the prediction
of the standard model.Comment: Replaced with published version. Included journal reference and DO
Search for new physics with same-sign isolated dilepton events with jets and missing transverse energy
A search for new physics is performed in events with two same-sign isolated
leptons, hadronic jets, and missing transverse energy in the final state. The
analysis is based on a data sample corresponding to an integrated luminosity of
4.98 inverse femtobarns produced in pp collisions at a center-of-mass energy of
7 TeV collected by the CMS experiment at the LHC. This constitutes a factor of
140 increase in integrated luminosity over previously published results. The
observed yields agree with the standard model predictions and thus no evidence
for new physics is found. The observations are used to set upper limits on
possible new physics contributions and to constrain supersymmetric models. To
facilitate the interpretation of the data in a broader range of new physics
scenarios, information on the event selection, detector response, and
efficiencies is provided.Comment: Published in Physical Review Letter
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