High Power Ultrasound to Recover Fine Particles in Flotation Process

9 pages, 6 figures.-- Communication presented at: Forum Acusticum Sevilla 2002 (Sevilla, Spain, 16-20 Sep 2002), comprising: 3rd European Congress on Acoustics; XXXIII Spanish Congress on Acoustics (TecniAcústica 2002); European and Japanese Symposium on Acoustics; 3rd Iberian Congress on Acoustics.-- Special issue of the journal Revista de Acústica, Vol. XXXIII, year 2002.The flotation process to recover useful substances from minerals has been used for dozens of years. For the flotation, air bubbles in a water solution of finely ground mineral particles must be introduced. The particles were prepared with chemical substances (surfactants) to be caught by the bubbles.Some attempts were made to improve the whole process, the best results reported were obtained for a technique called the "high energy" flotation experiments, [1] [2][3]. It seems that the recovering of the useful substances can be improved if some energy can be injected to the reactor with the metallurgic pulp. This suggests that an ultrasonic field can also improve the recovering in flotation. In this paper an application of acoustic cavitation to the flotation process is explored.The authors would like to thank the financial support of project FONDECYT 1010243.Peer reviewe

Estrategias de enseñanza que emplean los docentes para desarrollar en los estudiantes el pensamiento reflexivo y crítico: estado del arte en México (1990-2013)

La exigencia de un esfuerzo de reflexividad se constituye como punto de partida indispensable para el diseño de estrategias y metodologías que guíen el desarrollo profesional, académico y de investigación (Pacheco, 2009: 40). Es necesario explorar los factores que influyen en el distanciamiento entre profesores y alumnos, así como las limitaciones que presentan las actuales prácticas de enseñanza-aprendizaje, en las cuales predomina la acumulación de información por sobre el ánimo de promover una verdadera capacidad de pensar. En función de este distanciamiento crítico, profesores y alumnos enfrentarían el desafío de actualizar de manera permanente las estrategias epistemológicas, pedagógicas y didácticas que les permitan enseñar y aprender la capacidad de pensar y de razonar como tareas fundamentales de la formación. El despliegue de estrategias de tipo reflexivo apunta de manera preliminar a remover las inercias arraigadas y anquilosadas en el medio escolar y académico, para posteriormente valorar el peso histórico del conocimiento producido, así como su potencial heurístico.Desde el surgimiento de la enfermería moderna en Iberoamérica, ocurrido en los inicios del siglo pasado, ha venido cobrando importancia la formación de las nuevas generaciones de profesionistas, con esto nos referimos a la educación institucional; primero en los hospitales, posteriormente bajo el cobijo de las escuelas y facultades de medicina y finalmente en las escuelas y facultades de enfermería, principalmente dependientes de universidades públicas (Cárdenas, 2005: 120-129). En ese largo camino, se ha buscado el equilibrio o la congruencia entre los perfiles académico y laboral, esto es, que la formación de los egresados sea acorde con su desempeño profesional en el mercado laboral. Esto ha significado revisar de manera permanente los conocimientos, métodos, técnicas y estrategias de enseñanza y aprendizaje de las nuevas generaciones de enfermeras y enfermeros, manteniendo una vinculación permanente entre la docencia y la asistencia. En la actualidad, la formación de profesionistas en enfermería que respondan de manera eficiente, oportuna, asertiva y humanística a las demandas del cuidado de la vida y al mantenimiento y/o restablecimiento de la salud de una persona no es tarea fácil, toda vez que existe un alto nivel de complejidad en los procesos de vida-salud, salud-enfermedad y vida-muerte; donde el cuidado formal que brinda este profesional implica el establecimiento de un vínculo entre dos seres –el cuidado y el cuidador-, a lo largo del ciclo vital, orientado a la promoción, protección, recuperación y rehabilitación de la salud, así como a atender la enfermedad, para contribuir al desarrollo de una vida digna y plena, o en su caso, ayudar a bien morir

Impacto de la ecografía volumétrica portátil en el sondaje vesical por retención urinaria en una unidad de medicina interna

Aim: To estimate the impact of the use of portable bladder volumetric ultrasound on bladder catheterization due to suspicion of urinary retention in an internal medicine unit. Methodology: Study of retrospective cohorts, comparing the cohort exposed to the availability of bladder ultrasound, with the not exposed the previous year. All records in the Electronic Medical Record (EHR) of short-term permanent bladder catheters in adult patients admitted to the Internal Medicine hospitalization unit of the University Hospital Fundación Alcorcón (HUFA) during the years 2015 and 2016 were analyzed. The urinary retention frequency is estimated as the cause of the catheterization after the device has been incorporated into the unit and compared with the frequency of catheterization during the same period of the previous year in the same unit. It is estimated that the impact of having this device on the urinary retention frequency is the reason for the catheterization. Results: 134 catheters are included in 113 patients, 62 in the group without ultrasound and 72 in the group with ultrasound. The frequency of catheterizations due to retention is reduced from 47.5% to 21.4% after introducing the ultrasound unit into the unit. This represents a 50% reduction (adjusted RR=0.48; CI95%:0.27-0.84, p=0.01) in the frequency of urinary catheterization for suspected urinary retention.Objetivo: Estimar el impacto que el uso de ecógrafo vesical tiene en los sondajes vesicales por sospecha de retención urinaria de una unidad de Medicina interna.Metodología: Estudio de cohortes retrospectivas, comparando la cohorte expuesta a la disponibilidad del ecógrafo vesical, con la no expuesta el año previo. Se analizan todos los registros en la Historia Clínica Electrónica (HCE) de sondajes vesicales permanentes de corta duración en pacientes adultos que ingresaron en la unidad de hospitalización de Medicina Interna del Hospital Universitario Fundación Alcorcón (HUFA) durante los años 2015 y 2016. Se estima la frecuencia de retención urinaria como causa del sondaje después de la incorporación del dispositivo en la unidad y se compara con la frecuencia en sondajes durante el mismo periodo del año anterior en la misma unidad. Se estima el impacto que disponer de este dispositivo tiene en la frecuencia de retención urinaria como motivo del sondaje.Resultados: Se incluyen 134 sondajes en 113 pacientes, 62 en el grupo sin ecógrafo y 72 en el grupo con ecógrafo. La frecuencia de sondajes por retención se reduce del 47.5% al 21.4% después de introducir el ecógrafo en la unidad. Esto supone una reducción del 50% (RR ajustado= 0.48; IC95%:0.27-0.84, p=0.01) en la frecuencia de sondaje vesical por sospecha de retención urinaria

Flux emergence event underneath a filament

Flux emergence phenomena are relevant at different temporal and spatial scales.We have studied a flux emergence region underneath a filament. This filament elevated itselfsmoothly, and the associated CME reached the Earth. In this study we investigate the size andthe amount of flux in the emergence event. The flux emergence site appeared just beneath afilament. The emergence acquired a size of 24 Mm in half a day. The unsigned magnetic fluxdensity from LOS-magnetograms was around 1 kG at its maximum. The transverse field as wellas the filament eruption were also analysed.Ministerio de Economía y Competitivida

Searching for Carrington-like events and their signatures and triggers

The Carrington storm in 1859 is considered to be the major geomagnetic disturbance related to solar activity. In a recent paper, Cid et al. (2015) discovered a geomagnetic disturbance case with a profile extraordinarily similar to the disturbance of the Carrington event at Colaba, but at a mid-latitude observatory, leading to a reinterpretation of the 1859 event. Based on those results, this paper performs a deep search for other ?Carrington-like? events and analyses interplanetary observations leading to the ground disturbances which emerged from the systematic analysis. The results of this study based on two Carrington-like events (1) reinforce the awareness about the possibility of missing hazardous space weather events as the large H-spike recorded at Colaba by using global geomagnetic indices, (2) argue against the role of the ring current as the major current involved in Carrington-like events, leaving field-aligned currents (FACs) as the main current involved and (3) propose abrupt southward reversals of IMF along with high solar wind pressure as the interplanetary trigger of a Carrington-like event.Ministerio de Economía y Competitivida

Modeling the recovery phase of extreme geomagnetic storms

Ministerio de Ciencia e InnovaciónJunta de Comunidades de Castilla La-Manch

Influence of the Human Development Index on the Maternal–Perinatal Morbidity and Mortality of Pregnant Women with SARS-CoV-2 Infection: Importance for Personalized Medical Care

This study (FIS-PI18/00912) was supported by the Instituto de Salud Carlos III (Plan Estatal de I + D + i 2013–2016) and cofinanced by the European Development Regional Fund ‘‘A way to achieve Europe’’ (ERDF) and B2017/BMD-3804 MITIC-CM.Coronavirus disease-19 (COVID-19) is perhaps the most worrisome pandemic in the 21st century, having entailed devastating consequences for the whole society during the last year. Different studies have displayed an existing association between pregnancy and COVID-19 severity due to the various physiological changes that occur during gestation. Recent data identified maternal country of origin as an important determinant of COVID-19 presentation in pregnant women. However, the explanation of this fact remains to be fully elucidated. Therefore, the purpose of this work is to analyze the possible relationship between Human Development Index (HDI) of maternal country of origin with the morbimortality of pregnant women and their newborns. Here, we conducted a multicentric, ambispective, observational case-control study (1:1 ratio) and compare with the HDI of each country (group 1—very high HDI, group 2—high HDI, group 3—medium HDI, and group 4—low HDI). In total, 1347 pregnant women with confirmed SARV-CoV-2 infection (cases) were enrolled, and each was paired with one control to give a total number of 2694 participants from 81 tertiary care centers. Among the women with SARS-CoV-2 infection, more cases were produced of perinatal mortality, overall maternal morbidity, COVID-19 maternal morbidity, C-sections, hypertensive maternal morbidity, and perinatal morbidity. Our results described an inverse association between HDI and maternofetal morbidity and mortality. Moreover, the countries with an HDI lower than 1 showed higher rates of patients with maternal COVID-19-related morbidity (6.0% vs. 2.4%, p < 0.001), a need for oxygen therapy (4.7% vs. 1.8%, p < 0.001), and maternal ICU admission (2.6% vs. 1.0%, p = 0.007). Compared to other risk factors such as overweight, obesity, preexisting and obstetric comorbidities, HDI emerged as an independent risk factor explaining much of the increased maternal–perinatal morbidity and mortality detected in our group of cases. Further research is needed to establish to confirm the real impact of this factor and its components on pregnancy outcomes.Depto. de Salud Pública y Materno - InfantilFac. de MedicinaTRUEUnión EuropeaComunidad de MadridInstituto de Salud Carlos IIIpu

Effectiveness of the Epley’s maneuver performed in primary care to treat posterior canal benign paroxysmal positional vertigo: study protocol for a randomized controlled trial

BACKGROUND: Vertigo is a common medical condition with a broad spectrum of diagnoses which requires an integrated approach to patients through a structured clinical interview and physical examination. The main cause of vertigo in primary care is benign paroxysmal positional vertigo (BPPV), which should be confirmed by a positive D-H positional test and treated with repositioning maneuvers. The objective of this study is to evaluate the effectiveness of Epley’s maneuver performed by general practitioners (GPs) in the treatment of BPPV. METHODS/DESIGN: This study is a randomized clinical trial conducted in the primary care setting. The study’s scope will include two urban primary care centers which provide care for approximately 49,400 patients. All patients attending these two primary care centers, who are newly diagnosed with benign paroxysmal positional vertigo, will be invited to participate in the study and will be randomly assigned either to the treatment group (Epley’s maneuver) or to the control group (a sham maneuver). Both groups will receive betahistine. Outcome variables will be: response to the D-H test, patients’ report on presence or absence of vertigo during the previous week (dichotomous variable: yes/no), intensity of vertigo symptoms on a Likert-type scale in the previous week, total score on the Dizziness Handicap Inventory (DHI) and quantity of betahistine taken. We will use descriptive statistics of all variables collected. Groups will be compared using the intent-to-treat approach and either parametric or nonparametric tests, depending on the nature and distribution of the variables. Chi-square test or Fisher’s exact test will be conducted to compare categorical measures and Student’s t-test or Mann–Whitney U-test will be used for intergroup comparison variables. DISCUSSION: Positive results from our study will highlight that treatment of benign paroxysmal positional vertigo can be performed by trained general practitioners (GPs) and, therefore, its widespread practice may contribute to improve the quality of life of BPPV patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01969513

Effectiveness of the Epley's maneuver performed in primary care to treat posterior canal benign paroxysmal positional vertigo: study protocol for a randomized controlled trial

Background: Vertigo is a common medical condition with a broad spectrum of diagnoses which requires an integrated approach to patients through a structured clinical interview and physical examination. The main cause of vertigo in primary care is benign paroxysmal positional vertigo (BPPV), which should be confirmed by a positive D-H positional test and treated with repositioning maneuvers. The objective of this study is to evaluate the effectiveness of Epley's maneuver performed by general practitioners (GPs) in the treatment of BPPV. Methods/Design: This study is a randomized clinical trial conducted in the primary care setting. The study's scope will include two urban primary care centers which provide care for approximately 49,400 patients. All patients attending these two primary care centers, who are newly diagnosed with benign paroxysmal positional vertigo, will be invited to participate in the study and will be randomly assigned either to the treatment group (Epley's maneuver) or to the control group (a sham maneuver). Both groups will receive betahistine. Outcome variables will be: response to the D-H test, patients' report on presence or absence of vertigo during the previous week (dichotomous variable: yes/no), intensity of vertigo symptoms on a Likert-type scale in the previous week, total score on the Dizziness Handicap Inventory (DHI) and quantity of betahistine taken. We will use descriptive statistics of all variables collected. Groups will be compared using the intent-to-treat approach and either parametric or nonparametric tests, depending on the nature and distribution of the variables. Chi-square test or Fisher's exact test will be conducted to compare categorical measures and Student's t-test or Mann-Whitney U-test will be used for intergroup comparison variables. Discussion: Positive results from our study will highlight that treatment of benign paroxysmal positional vertigo can be performed by trained general practitioners (GPs) and, therefore, its widespread practice may contribute to improve the quality of life of BPPV patients

Metabolic Syndrome as a Cardiovascular Disease Risk Factor: Patients Evaluated in Primary Care

To estimate the prevalence of metabolic syndrome (MS) in a population receiving attention in primary care centers (PCC) we selected a random cohort of ostensibly normal subjects from the registers of 5 basic-health area (BHA) PCC. Diagnosis of MS was with the WHO, NCEP and IDF criteria. Variables recorded were: socio-demographic data, CVD risk factors including lipids, obesity, diabetes, blood pressure and smoking habit and a glucose tolerance test outcome. Of the 720 individuals selected (age 60.3 ± 11.5 years), 431 were female, 352 hypertensive, 142 diabetic, 233 pre-diabetic, 285 obese, 209 dyslipemic and 106 smokers. CVD risk according to the Framingham and REGICOR calculation was 13.8 ± 10% and 8.8 ± 9.8%, respectively. Using the WHO, NCEP and IDF criteria, MS was diagnosed in 166, 210 and 252 subjects, respectively and the relative risk of CVD complications in MS subjects was 2.56. Logistic regression analysis indicated that the MS components (WHO set), the MS components (IDF set) and the female gender had an increased odds ratio for CVD of 3.48 (95CI%: 2.26–5.37), 2.28 (95%CI: 1.84–4.90) and 2.26 (95%CI: 1.48–3.47), respectively. We conclude that MS and concomitant CVD risk is high in ostensibly normal population attending primary care clinics, and this would necessarily impinge on resource allocation in primary care