Electrochemical Characterisation of Filter Media Properties and Their Exploitation in Enhanced Filtration

Streaming potential measurements for the surface charge characterisation of different filter media types and materials were used. The equipment was developed further so that measurements could be taken along the surfaces, and so that tubular membranes could also be measured. The streaming potential proved to be a very useful tool in the charge analysis of both clean and fouled filter media. Adsorption and fouling could be studied, as could flux, as functions of time. A module to determine the membrane potential was also constructed. The results collected from the experiments conducted with these devices were used in the study of the theory of streaming potential as an electrokinetic phenomenon. Several correction factors, which are derived to take into account the surface conductance and the electrokinetic flow in very narrow capillaries, were tested in practice. The surface materials were studied using FTIR and the results compared with those from the streaming potentials. FTIR analysis was also found to be a useful tool in the characterisation of filters, as well as in the fouling studies. Upon examination of the recorded spectra from different depths in a sample it was possible to determine the adsorption sites. The influence of an external electric field on the cross flow microflltration of a binary protein system was investigated using a membrane electroflltration apparatus. The results showed that a significant improvement could be achieved in membrane filtration by using the measured electrochemical properties to help adjust the process conditions.

Dynamic electrostatic force microscopy in liquid media

We present the implementation of dynamic electrostatic force microscopy in liquid media. This implementation enables the quantitative imaging of local dielectric properties of materials in electrolyte solutions with nanoscale spatial resolution. Local imaging capabilities are obtained by probing the frequency-dependent and ionic concentration-dependent electrostatic forces at high frequency (>1 MHz), while quantification of the interaction forces is obtained with finite-element numerical calculations. The results presented open a wide range of possibilities in a number of fields where the dielectric properties of materials need to be probed at the nanoscale and in a liquid environment.

Dynamic electrostatic force microscopy in liquid media

We present the implementation of dynamic electrostatic force microscopy in liquid media. This implementation enables the quantitative imaging of local dielectric properties of materials in electrolyte solutions with nanoscale spatial resolution. Local imaging capabilities are obtained by probing the frequency-dependent and ionic concentration-dependent electrostatic forces at high frequency (>1 MHz), while quantification of the interaction forces is obtained with finite-element numerical calculations. The results presented open a wide range of possibilities in a number of fields where the dielectric properties of materials need to be probed at the nanoscale and in a liquid environment.

Propagation through fractal media: The Sierpinski gasket and the Koch curve

We present new analytical tools able to predict the averaged behavior of fronts spreading through self-similar spatial systems starting from reaction-diffusion equations. The averaged speed for these fronts is predicted and compared with the predictions from a more general equation (proposed in a previous work of ours) and simulations. We focus here on two fractals, the Sierpinski gasket (SG) and the Koch curve (KC), for two reasons, i.e. i) they are widely known structures and ii) they are deterministic fractals, so the analytical study of them turns out to be more intuitive. These structures, despite their simplicity, let us observe several characteristics of fractal fronts. Finally, we discuss the usefulness and limitations of our approa

Evolución de los conocimientos acerca de los trastornos del comportamiento alimentario, a través de una intervención educativa en estudiantes de enseñanza post-obligatoria

Introducción: A pesar de ser considerados eventos infrecuentes en comparación a otros estados patológicos relacionados con la alimentación, en los últimos años y en diferentes países, se constata un incremento de las tasas de incidencia y prevalencia de los Tras - tornos del Comportamiento Alimentario; la mayoría de estudios que analizan los factores que pueden influir en su aparición, suelen implicar a jóvenes y adolescentes de poblaciones pre-mórbidas o mórbidas, siendo menos frecuentes los realizados sobre población sana y estándar. Objetivos: Evaluar el nivel de conocimientos acerca de los Trastornos del Comportamiento Alimentario y comprobar la eficacia de una intervención educativa, en jóvenes de una población presumiblemente sana. Métodos: Estudio de intervención con evaluación pre y post intervención, a través de un cuestionario previamente validado de 10 preguntas cerradas y abiertas, en estudiantes de Fisioterapia, Educación Infantil y Hostelería. Resultados: Respondieron el cuestionario inicial 154 estu diantes, 85 universitarios y 39 de ciclo formativo en Hostelería, mayoritariamente mujeres (68%) y con una edad media de 20,8 años. Los estudiantes demostraron un nivel medio de conocimientos inicial, mayor en las mujeres y en los estudiantes universitarios que en los de formación profesional. Los factores de riesgo y las manifestaciones clínicas fueron los aspectos menos conocidos por los estudiantes. La intervención educativa realizada en los 35 estudiantes de Hostelería que participaron en el taller y respondieron el cuestionario post-intervención, consiguió elevar el nivel de conocimientos hasta una calificación media superior a la inicial y a la de los grupos en que no se realizó la intervención. Discusión y conclusiones: A pesar de que la intervención realizada resultó eficaz para mejorar el nivel de conocimientos en muchos de los participantes, los resultados del cuestionario post-intervención revelan la necesidad de educar a los jóvenes en los rasgos que definen y caracterizan un Trastorno del Compor tamiento Alimen - tario, adaptando el abordaje de los mismos a su realidad social. La inclusión de temas relacionados con la nutrición y la salud en los programas curriculares de los estudios post-obligatorios mejoraría el nivel de conocimientos entre los futuros profesionales de los ámbitos de la salud, la educación y la hostelería/restauración.

The Influence of the media and advertising on eating disorders

This article describes a literature review of the influence of advertising and the media on Eating Disorders (ED). Research published in scientific journals in various fields of social sciences such as sychology, psychiatry and communication science has enabled us to conclude that the content displayed in the media, including advertising, are enhancers of disorders and contribute significantly to body issatisfaction in relation to the perceived idea of beauty, it also facilitates the development of weight loss strategies in women and gain of muscle mass in men.

Learning in Digital Media: the legacy of McLuhan and his Impact on Formal Education

This paper describes a bibliographic analysis of the vision of Marshal McLuhan and the vision adopted by diverse current authors regarding the use of new interactive learning technologies. The paper also analyzes the transformation that will have to take place in the formal surroundings of education in order to improve their social function. The main points of view and contributions made by diverse authors are discussed. It is important that all actors involved in the educational process take in consideration these contributions in order to be ready for future changes.

Efecto de la suplementación con ácidos grasos de cadena media sobre la evolución de peso en lechones con poco peso al nacimiento

La evolución de peso en los períodos de lactación y transición de 583 lechones fue estudiada mediante un análisis estadístico, evaluando el efecto de la suplementación con ácidos grasos de cadena media (AGCM) en lechones con poco peso al nacimiento. 188 de los 375 lechones que nacieron con un peso al nacimiento (PN) <1250 g recibieron 3mL de AGCM cada 24 h durante los primeros 3 días de vida; su peso medio al destete (día 28) fue inferior respecto al grupo control (lechones no suplementados) (-114,17 g). No obstante, 106 de los 180 lechones nacidos con un PN <1000 g fueron suplementados, y su peso medio al destete y a finales de transición (día 63) fue superior respecto al grupo control (destete: +315,16 g; día 63: +775,47 g). Finalmente, los lechones suplementados con PN<800 g tuvieron los peores resultados: su diferencia de peso medio al destete fue de -177,58 g respecto al grupo control. Por lo tanto, en esta prueba fueron estudiados los lechones con un PN entre 800 y 999 g porque el grupo suplementado al destete tuvo una diferencia de peso medio considerable respecto al grupo control:+511,58 g. Asimismo, considerando una probabilidad de error inferior a 0,05, no hubieron diferencias significativas en las diferentes categorías de PN analizadas. De todas maneras, es importante destacar el alto grado de significación en la suplementación con AGCM en lechones con PN entre 800 y 999g (P=0,059). Por otra parte, el PN del grupo suplementado con PN<1000 g fue inferior que el del grupo no suplementado con PN<1000 g; esta diferencia de PN fue significativa (P=0,004) y como consecuencia el grado de significación en la suplementación con AGCM en lechones con PN entre 800 y 999 g fue inferior al esperado. Además, en esta prueba se incluyeron algunos resultados generales y también un análisis simple de supervivencia, aunque no era el objetivo principal

Nocturnal Transcutaneous Carbon Dioxide and Early Changes in Atherosclerosis in Pre- and Postmenopausal Women

The risk of cardiovascular diseases and sleep-disordered breathing increases after menopause. This cross-sectional study focuses on overnight transcutaneous carbon dioxide (TcCO₂) measurements and their power to predict changes in the early markers of cardiovascular and metabolic diseases. The endothelial function of the brachial artery, the intima-media thickness of the carotid artery, blood pressure, glycosylated hemoglobin A1C and plasma levels of cholesterols and triglycerides were used as markers of cardiovascular and metabolic diseases. The study subjects consisted of healthy premenopausal women of 46 years of age and postmenopausal women of 56 years of age. From wakefulness to sleep, the TcCO₂ levels increased more in postmenopausal women than in premenopausal women. In estrogen-users the increase in TcCO₂ levels was even more pronounced than in other postmenopausal women. From the dynamic behaviour of the nocturnal TcCO₂ signal, several important features were detected. These TcCO₂ features had a remarkable role in the prediction of endothelial dysfunction and thickening of the carotid wall in healthy premenopausal women. In addition, these TcCO₂ features were linked with blood pressure, lipid profile and glucose balance in postmenopausal women. The nocturnal TcCO₂ profile seems to contain significant information, which is associated with early changes in cardiovascular diseases in middle-aged women. TcCO₂ might not only measure the tissue carbon dioxide levels, but the TcCO₂ signal variation may also reflect peripheral vasodynamic events caused by increased sympathetic activity during sleep.

Effects of cobalt-chromium everolimus eluting stents or bare metal stent on fatal and non-fatal cardiovascular events: patient level meta-analysis

Objectives: To examine the safety and effectiveness of cobalt-chromium everolimus eluting stents compared with bare metal stents. Design: Individual patient data meta-analysis of randomised controlled trials. Cox proportional regression models stratified by trial, containing random effects, were used to assess the impact of stent type on outcomes. Hazard ratios with 95% confidence interval for outcomes were reported. Data sources and study selection: Medline, Embase, the Cochrane Central Register of Controlled Trials. Randomised controlled trials that compared cobalt-chromium everolimus eluting stents with bare metal stents were selected. The principal investigators whose trials met the inclusion criteria provided data for individual patients. Primary outcomes: The primary outcome was cardiac mortality. Secondary endpoints were myocardial infarction, definite stent thrombosis, definite or probable stent thrombosis, target vessel revascularisation, and all cause death. Results: The search yielded five randomised controlled trials, comprising 4896 participants. Compared with patients receiving bare metal stents, participants receiving cobalt-chromium everolimus eluting stents had a significant reduction of cardiac mortality (hazard ratio 0.67, 95% confidence interval 0.49 to 0.91; P=0.01), myocardial infarction (0.71, 0.55 to 0.92; P=0.01), definite stent thrombosis (0.41, 0.22 to 0.76; P=0.005), definite or probable stent thrombosis (0.48, 0.31 to 0.73; P<0.001), and target vessel revascularisation (0.29, 0.20 to 0.41; P<0.001) at a median follow-up of 720 days. There was no significant difference in all cause death between groups (0.83, 0.65 to 1.06; P=0.14). Findings remained unchanged at multivariable regression after adjustment for the acuity of clinical syndrome (for instance, acute coronary syndrome v stable coronary artery disease), diabetes mellitus, female sex, use of glycoprotein IIb/IIIa inhibitors, and up to one year v longer duration treatment with dual antiplatelets. Conclusions: This meta-analysis offers evidence that compared with bare metal stents the use of cobalt-chromium everolimus eluting stents improves global cardiovascular outcomes including cardiac survival, myocardial infarction, and overall stent thrombosis.

Multi-Eruption Solar Energetic Particle Events Observed by SOHO/ERNE

In the last two decades of studying the Solar Energetic Particle (SEP) phenomenon, intensive emphasis has been put on how and when and where these SEPs are injected into interplanetary space. It is well known that SEPs are related to solar flares and CMEs. However, the role of each in the acceleration of SEPs has been under debate since the major role was taken from flares ascribed to CMEs step by step after the skylab mission, which started the era of CME spaceborn observations. Since then, the shock wave generated by powerful CMEs in between 2-5 solar radii is considered the major accelerator. The current paradigm interprets the prolonged proton intensity-time profile in gradual SEP events as a direct effect of accelerated SEPs by shock wave propagating in the interplanetary medium. Thus the powerful CME is thought of as a starter for the acceleration and its shock wave as a continuing accelerator to result in such an intensity-time profile. Generally it is believed that a single powerful CME which might or might not be associated with a flare is always the reason behind such gradual events.

In this work we use the Energetic and Relativistic Nucleus and Electrons ERNE instrument on board Solar and Heliospheric Observatory SOHO to present an empirical study to show the possibility of multiple accelerations in SEP events. In the beginning we found 18 double-peaked SEP events by examining 88 SEP events. The peaks in the intensity-time profile were separated by 3-24 hours. We divided the SEP events according to possible multiple acceleration into four groups and in one of these groups we find evidence for multiple acceleration in velocity dispersion and change in the abundance ratio associated at transition to the second peak. Then we explored the intensity-time profiles of all SEP events during solar cycle 23 and found that most of the SEP events are associated with multiple eruptions at the Sun and we call those events as Multi-Eruption Solar Energetic Particles (MESEP) events. We use the data available by Large Angle and Spectrometric Coronograph LASCO on board SOHO to determine the CME associated with such events and YOHKOH and GOES satellites data to determine the flare associated with such events. We found four types of MESEP according to the appearance of the peaks in the intensity-time profile in large variation of energy levels. We found that it is not possible to determine whether the peaks are related to an eruption at the Sun or not, only by examining the anisotropy flux, He/p ratio and velocity dispersion. Then we chose a rare event in which there is evidence of SEP acceleration from behind previous CME. This work resulted in a conclusion which is inconsistent with the current SEP paradigm. Then we discovered through examining another MESEP event, that energetic particles accelerated by a second CME can penetrate a previous CME-driven decelerating shock. Finally, we report the previous two MESEP events with new two events and find a common basis for second CME SEPs penetrating previous decelerating shocks. This phenomenon is reported for the first time and expected to have significant impact on modification of the current paradigm of the solar energetic particle events.

Effects of cobalt-chromium everolimus eluting stents or bare metal stent on fatal and non-fatal cardiovascular events: patient level meta-analysis

Objectives: To examine the safety and effectiveness of cobalt-chromium everolimus eluting stents compared with bare metal stents. Design: Individual patient data meta-analysis of randomised controlled trials. Cox proportional regression models stratified by trial, containing random effects, were used to assess the impact of stent type on outcomes. Hazard ratios with 95% confidence interval for outcomes were reported. Data sources and study selection: Medline, Embase, the Cochrane Central Register of Controlled Trials. Randomised controlled trials that compared cobalt-chromium everolimus eluting stents with bare metal stents were selected. The principal investigators whose trials met the inclusion criteria provided data for individual patients. Primary outcomes: The primary outcome was cardiac mortality. Secondary endpoints were myocardial infarction, definite stent thrombosis, definite or probable stent thrombosis, target vessel revascularisation, and all cause death. Results: The search yielded five randomised controlled trials, comprising 4896 participants. Compared with patients receiving bare metal stents, participants receiving cobalt-chromium everolimus eluting stents had a significant reduction of cardiac mortality (hazard ratio 0.67, 95% confidence interval 0.49 to 0.91; P=0.01), myocardial infarction (0.71, 0.55 to 0.92; P=0.01), definite stent thrombosis (0.41, 0.22 to 0.76; P=0.005), definite or probable stent thrombosis (0.48, 0.31 to 0.73; P<0.001), and target vessel revascularisation (0.29, 0.20 to 0.41; P<0.001) at a median follow-up of 720 days. There was no significant difference in all cause death between groups (0.83, 0.65 to 1.06; P=0.14). Findings remained unchanged at multivariable regression after adjustment for the acuity of clinical syndrome (for instance, acute coronary syndrome v stable coronary artery disease), diabetes mellitus, female sex, use of glycoprotein IIb/IIIa inhibitors, and up to one year v longer duration treatment with dual antiplatelets. Conclusions: This meta-analysis offers evidence that compared with bare metal stents the use of cobalt-chromium everolimus eluting stents improves global cardiovascular outcomes including cardiac survival, myocardial infarction, and overall stent thrombosis.

De scientia Dei media

Invocatio: kreik.

Digital social media: An interactive technology incorporated as a competitive advantage for business

In a more transparent and dynamic world, in which consumers trust other consumers more for advice and recommendations on products and services, the continuity of organizations appears to be associated with socialization, the sharing of interests and the interaction with the audience. This is associated with the incorporation of digital technologies to business, specifically the use of social media. Consequently, it is timely and interesting to explore the phenomenon of virtual socialization, although it is a littlestudied field and what is needed is an innovative and theoretical approach based upon theories of marketing and communication. Expertise in these areas is present in all organizations and their performance is important for appropriate development of them. This work is a qualitative analysis about the behavior, reactions and attitudes of individuals to organizations, in order to understand the social factors that contribute to sustainable competitive advantages of organizations which can support strategic and future actions. We conclude that relevant factors associated with the tacit knowledge of the organization, specifically to learning and social interaction of the organization and their knowledge of virtual communities. The higher the coexistence of factors, the more difficult is the replication and greater will be the hypothesis of sustainable competitive advantage.