2,912 research outputs found

    SISTEMAS DE PRODUCCIÓN DE ACUACULTURA CON RECIRCULACIÓN DE AGUA PARA LA REGIÓN NORTE, NORESTE Y NOROESTE DE MÉXICO

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    Aquaculture is expanding and developing in practically all the regions of the world. The demand of the world-wide population by aquatic products is increasing, whereas the production from capture of fisheries has been being reduced, reaching many of them their maximum productive potential. As result of, sustaining fish supplies from capture fisheries it will not be possible to meet the growing global demand for aquatic food. Therefore, the aquaculture seems to have the potential to make a significant contribution to the production of these foods, in order to meet the growing population demand. Nevertheless, in order to accomplish it, the producer faces critical challenges. The development of these activities intensifies substantially, and requires to be diversified, producing new species and creating new systems and practices of production. The production systems of aquatic animals, particularly those based on technologies of water recirculation, appears to be an excellent alternative for producing, in regions of the North of Mexico, in where the water is scarce.Aquaculture, word wide population, aquatic food., Agribusiness,

    Multi-site observations of Delta Scuti stars 7 Aql and 8 Aql (a new Delta Scuti variable): The twelfth STEPHI campaign in 2003

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    We present an analysis of the pulsation behaviour of the Delta Scuti stars 7 Aql (HD 174532) and 8 Aql (HD 174589) -- a new variable star -- observed in the framework of STEPHI XII campaign during 2003 June--July. 183 hours of high precision photometry were acquired by using four-channel photometers at three sites on three continents during 21 days. The light curves and amplitude spectra were obtained following a classical scheme of multi-channel photometry. Observations in different filters were also obtained and analyzed. Six and three frequencies have been unambiguously detected above a 99% confidence level in the range 0.090 mHz--0.300 mHz and 0.100 mHz-- 0.145 mHz in 7 Aql and 8 Aql respectively. A comparison of observed and theoretical frequencies shows that 7 Aql and 8 Aql may oscillate with p modes of low radial orders, typical among Delta Scuti stars. In terms of radial oscillations the range of 8 Aql goes from n=1 to n=3 while for 7 Aql the range spans from n=4 to n=7. Non-radial oscillations have to be present in both stars as well. The expected range of excited modes according to a non adiabatic analysis goes from n=1 to n=6 in both stars.Comment: 8 pages, 7 fugures, 5 tables, accepted for publication in Astronomical Journa

    Impact of Prior Coronary Artery Bypass Grafting in Patients ≥75 Years Old Presenting With Acute Myocardial Infarction (From the National Readmission Database)

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    Patients ≥75 years old presenting with acute myocardial infarction (AMI) have complex coronary anatomy in part due t Patients ≥75 years old presenting with acute myocardial infarction (AMI) have complex coronary anatomy in part due to prior coronary artery bypass grafting (CABG), percutaneous coronary interventions (PCI), calcific and valvular disease. Using the National Readmission Database from January 2016 to November 2017, we identified hospital admissions for acute myocardial infarction in patients ≥75 years old and divided them based on a history of CABG. We evaluated in-hospital outcomes, 30-day mortality, 30-day readmission and predictors of PCI in cohorts. Out of a total of 296,062 patients ≥75 years old presenting with an AMI, 42,147 (14%) had history of previous CABG. Most presented with a non-ST segment elevation myocardial infarction, and those with previous CABG had higher burden of co-morbidities and were more commonly man. The in-hospital mortality was significantly lower in those with previous CABG (6.7% vs 8.8%, adjusted odds ratio, 0.88, 95% confidence interval, 0.82 to 0.94). Medical therapy was more common in those with previous CABG and 30-day readmission rates were seen more frequently in those with prior CABG. Predictors of not undergoing PCI included previous PCI, female, older ager groups, heart failure, dementia, malignancy, and higher number of co-morbidities. In conclusion, in patients ≥75 years old with AMI the presence of prior CABG was associated with lower odds of in-hospital and 30-day mortality, as well as lower complications rates, and a decreased use of invasive strategies (PCI, CABG, and MCS). However, 30-day MACE readmission was higher in those with previous CABG. o prior coronary artery bypass grafting (CABG), percutaneous coronary interventions (PCI), calcific and valvular disease. Using the National Readmission Database from January 2016 to November 2017, we identified hospital admissions for acute myocardial infarction in patients ≥75 years old and divided them based on a history of CABG. We evaluated in-hospital outcomes, 30-day mortality, 30-day readmission and predictors of PCI in cohorts. Out of a total of 296,062 patients ≥75 years old presenting with an AMI, 42,147 (14%) had history of previous CABG. Most presented with a non-ST segment elevation myocardial infarction, and those with previous CABG had higher burden of co-morbidities and were more commonly man. The in-hospital mortality was significantly lower in those with previous CABG (6.7% vs 8.8%, adjusted odds ratio, 0.88, 95% confidence interval, 0.82 to 0.94). Medical therapy was more common in those with previous CABG and 30-day readmission rates were seen more frequently in those with prior CABG. Predictors of not undergoing PCI included previous PCI, female, older ager groups, heart failure, dementia, malignancy, and higher number of co-morbidities. In conclusion, in patients ≥75 years old with AMI the presence of prior CABG was associated with lower odds of in-hospital and 30-day mortality, as well as lower complications rates, and a decreased use of invasive strategies (PCI, CABG, and MCS). However, 30-day MACE readmission was higher in those with previous CABG

    Drivers of Bird- Window Collisions in Florida International University’s Modesto A. Maidique Campus

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    Bird-window collisions are among the top leading causes of death for birds in North America. Studies have found primary drivers of bird-window collisions to be window area, building size, and presence of vegetation around the buildings. We hypothesized that higher window area and vegetation would increase birdwindow collisions, with an inverse relationship between number of stories and bird-window collisions. Surveys were conducted for 21 consecutive days around six buildings at Florida International University (FIU) in October 2014. Using ArcGIS, 50m buffers were created around each building to calculate percent vegetation and ImageJ was used to calculate percent window cover. We collected 10 bird carcasses and 13 feather piles assumed to represent bird-window collisions. Most of the collisions (8 out of 21) occurred at the building with the lowest percent vegetation and low window area. Our sample size limits our ability to make general conclusions, however, our data is a part of a larger collaborative project that includes over 30 campuses across North America. Results from this larger project could provide insight on whether the magnitude of bird-window collisions relates to landscape structure and functional connectivity

    Redesign of the Jefferson Lab -300 kV DC Photo-Gun for High Bunch Charge Operations

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    Production of high bunch charge beams for the ElectronIon Collider (EIC) is a challenging task. High bunch charge (a few nC) electron beam studies at Jefferson Lab using an inverted insulator DC high voltage photo-gun showed evidence of space charge limitations starting at 0.3 nC, limiting the maximum delivered bunch charge to 0.7 nC for beam at -225 kV, 75 ps (FWHM) pulse width, and 1.64 mm (rms) laser spot size. The low extracted charge is due to the modest longitudinal electric field (Ez) at the photocathode leading to beam loss at the anode and downstream beam pipe. To reach the few nC high bunch charge goal, and to correct the beam deflection exerted by the non-symmetric nature of the inverted insulator photo-gun the existing photo-gun was modified. This contribution discusses the electrostatic design of the modified photo-gun obtained using CST Studio Suite’s electromagnetic field solver. Beam dynamics simulations performed using General Particle Tracer (GPT) with the resulting electrostatic field map obtained from the modified electrodes confirmed the validity of the new design

    Modelamientos de espacio interior realizados en Medellín durante la vigencia 2020, mediante tecnologías multimedia e interacción, para selección de acabados centrado en la percepción estética visual del usuario

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    The selection of interior finishing material is necessary to create atmospheres. At present it is done by quantitative indicators such as energy performance and life expectancy, leaving aside visual aesthetics. This research proposes a solution through multimedia technologies and interaction, for the selection of interior finishing material focused on the user, that incorporates the aesthetics and performance of the materials. The expected result is a methodology that helps to make decisions with simple multiple criteria, to determine the type of finishing material through the interactive evaluation of the aesthetic preferences of the end users. The reason for carrying out the research is that, with technological advances and the use of data collection tools, short and long distance customer doubts can be resolved and clarified, in addition to providing the routes and generating sensations about the selected interior finishes. To carry out virtualization, renderings, videos, experiences on the web and social networks will be carried out to generate an interactive experience.La selección del material de acabado interior es necesario para crear ambientes. En la actualidad se hace por indicadores cuantitativos como el rendimiento energético y la esperanza de vida, dejando de lados la estética visual. Esta investigación propone una solución mediante tecnologías multimedia e interacción, para la selección de material de acabado interior centrado en el usuario que incorpore la estética y el rendimiento de los materiales. Se espera como resultado una metodología que ayude a tomar decisiones con criterios múltiples simples, para determinar el tipo de material de acabado mediante la evaluación interactiva de las preferencias estéticas de los usuarios finales. La razón para ejecutar la investigación es que, con los avances tecnológicos y el uso de las herramientas de  adquisición de datos, se pueden resolver y aclarar dudas de los clientes a corta y larga distancia, además de proporcionar los recorridos y generar sensaciones sobre los acabados interiores seleccionados. Para llevar a cabo la virtualización se realizarán renderizaciones, videos, experiencias en web y las redes sociales para generar una experiencia de interactividad

    Our Sun. IV. The Standard Model and Helioseismology: Consequences of Uncertainties in Input Physics and in Observed Solar Parameters

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    Helioseismology provides a powerful tool to explore the deep interior of the Sun: for example, the adiabatic sound speed can be inferred with an accuracy of a few parts in 10,000. This has become a serious challenge to theoretical models of the Sun. Therefore, we have undertaken a self-consistent, systematic study of sources of uncertainties in the standard solar model, which must be understood before the helioseismic observations can be used as constraints on theory. We find that the largest uncertainty in the sound speed in the solar interior, namely, 3 parts in 1000, arises from uncertainties in the observed photospheric abundances of the elements; uncertainties of 1 part in 1000 arise from (1) the 4% uncertainty in the OPAL opacities, (2) the 5% uncertainty in the basic pp nuclear reaction rate, (3) the 15% uncertainty in the diffusion constants for the gravitational settling of helium, and (4) the 50% uncertainties in diffusion constants for the heavier elements. (Other investigators have shown that similar uncertainties arise from uncertainties in the interior equation of state and in rotation-induced turbulent mixing.) The predicted pre-main-sequence solar lithium depletion is a factor of order 20 (an order of magnitude larger than that predicted by earlier models that neglected gravitational settling and used older opacities), and is uncertain by a factor of 2. The predicted neutrino capture rate is uncertain by 30% for the Cl-37 experiment and by 3% for the Ga-71 experiments (not including uncertainties in the capture cross sections), while the B-8 neutrino flux is uncertain by 30%.Comment: LaTeX, 38 pages (including 8 figures); ApJ, in press. Added figures/color figurea available at http://www.cita.utoronto.ca/~boothroy/sun4.htm

    National Landscape of Hospitalizations in Patients with Left Ventricular Assist Device. Insights from the National Readmission Database 2010-2015

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    The number of patients with left ventricular assist devices (LVAD) has increased over the years and it is important to identify the etiologies for hospital admission, as well as the costs, length of stay and in-hospital complications in this patient group. Using the National Readmission Database from 2010 to 2015, we identified patients with a history of LVAD placement using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code V43.21. We aimed to identify the etiologies for hospital admission, patient characteristics, and in-hospital outcomes. We identified a total of 15,996 patients with an LVAD, the mean age was 58 years and 76% were males. The most common cause of hospital readmission after LVAD was heart failure (HF, 13%), followed by gastrointestinal (GI) bleed (11.8%), device complication (11.5%), and ventricular tachycardia/fibrillation (4.2%). The median length of stay was 6 days (3-11 days) and the median hospital costs was $12,723 USD. The in-hospital mortality was 3.9%, blood transfusion was required in 26.8% of patients, 20.5% had acute kidney injury, 2.8% required hemodialysis, and 6.2% of patients underwent heart transplantation. Interestingly, the most common cause of readmission was the same as the diagnosis for the preceding admission. One in every four LVAD patients experiences a readmission within 30 days of a prior admission, most commonly due to HF and GI bleeding. Interventions to reduce HF readmissions, such as speed optimization, may be one means of improving LVAD outcomes and resource utilization

    Peutz-Jeghers syndrome and duodeno-jejunal adenocarcinoma-therapeutic implications

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    The Peutz-Jeghers syndrome (PJS) is an autosomal dominant hamartomatous poliposis describred in 1921. Hemminki in 1997 described the presence of LKB-1 mutation tumor-suppressor gen.The patients with PJS develop a higher cumulative incidence of gastrointestinal, pancreas and extraintestinal tumors, being occasion of a renew interest on hamartomatous polyposis syndromes regarding the clinical care, cancer surveillance treatment and long term follow-up.We report the case of a 38 years old male, diagnosed of PJS who developed a multiple adenocarcinoma in duodenum and yeyunum. Surgically treated and with a long-term free disease survival of 11 years represents the sixth case reported in the spanish literature of PJS associated with a gastrointestinal tumor.A critical review, molecular alterations and the established criteria of tumor screening and surveillance are reviewed
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