Electrokinetic and hydrodynamic properties of charged-particles systems: From small electrolyte ions to large colloids

Dynamic processes in dispersions of charged spherical particles are of importance both in fundamental science, and in technical and bio-medical applications. There exists a large variety of charged-particles systems, ranging from nanometer-sized electrolyte ions to micron-sized charge-stabilized colloids. We review recent advances in theoretical methods for the calculation of linear transport coefficients in concentrated particulate systems, with the focus on hydrodynamic interactions and electrokinetic effects. Considered transport properties are the dispersion viscosity, self- and collective diffusion coefficients, sedimentation coefficients, and electrophoretic mobilities and conductivities of ionic particle species in an external electric field. Advances by our group are also discussed, including a novel mode-coupling-theory method for conduction-diffusion and viscoelastic properties of strong electrolyte solutions. Furthermore, results are presented for dispersions of solvent-permeable particles, and particles with non-zero hydrodynamic surface slip. The concentration-dependent swelling of ionic microgels is discussed, as well as a far-reaching dynamic scaling behavior relating colloidal long- to short-time dynamics

Analysis of the dyscalculia with the implementation of a design workshop in CATIA in a primary school in Puebla

In a rural context primary school where a pilot program of full-time schools was promoted and taking into account the component of the new curricular autonomy model 2017. A design and automation workshop was implemented using CATIA software, with the aim of demonstrating that primary students can overcome deficiencies in mathematical skills such as dyscalculia. The workshop was conducted with ten students between six and twelve years' old who, due to their rural context, have little contact with technology. For the realization of this workshop, a survey was carried out for the parents and for the children where the full acceptance of the workshop was manifested. In the same way, the participation of the Technological University of Puebla (UTP) was carried out through mechatronic engineering, which was in charge of teaching the workshop, through the management according to the new educational model. The CATIA software visibly favored students' mathematical skills when designing a march, in addition to reducing school absenteeism and generating a product (wooden tractor) that has more significant benefits than the famous Japanese toy. The evaluation of the project was registered in rubrics in a span of three phases. The end of the whole process we concluded that, due to its low cost, it is possible to implement this workshop in all federal and state primaries regardless of their context and also that any child can operate the calculation using CATIA. With this last observation, we demonstrate that dyscalculia is a myth

"Medio ambiente y desarrollo sostenible caso parque eólico San Juan y su conexión al sistema eléctrico interconectado nacional (SEIN)"

Este trabajo de investigación se justifica, por cuanto posee un valor teórico y una relevancia social por los beneficios que generara a las familias que radican en la comunidad de San Juan — Marcona, ubicado en la Región loa. El estudio se sustenta en la evaluación del impacto ambiental, verificación del plan de manejo ambiental y el desarrollo sostenible. En lo concerniente a energía renovables la actividad de generación de energía eléctrica mediante el recurso eólico, en la transmisión y distribución de energía eléctrica. Teniendo en cuenta lo indicado anteriormente y de la necesidad de poder ampliar el horizonte sobre la generación de energía, especialmente en energía renovables realizaremos ejecutar el proyecto "Parque Eólico San Juan y su conexión al Sistema Eléctrico Interconectado Nacional", ubicado en el distrito de Marcona, provincia de Nasca, región de lea. El proyecto indicado tiene como objetivo transmitir la energía producida por el Parque Eólico San Juan — Marcona; al SEIN, mediante una línea de transmisión de 32.5 km que unirá la Subestación Eléctrica del Parque Eólico San Juan con la Subestación Eléctrica existente en Mamona — Ice.Trabajo academic

The use of audio-relaxation does not affect the basketball free throw of young college students

INTRODUCTION: As the pressure of competition increase, the athlete will begin to doubt or feel insecure, generating muscular tension and difficulty in the movement. In sports, especially basketball, relaxation is a key part of fine-skills coordination. For this reason, it is determinate that audio-relaxation can become of paramount importance in sport. PURPOSE: To determine if the basketball free throw is influenced by audio-relaxation in a group of physically active college students. METHODS: Eight physically active, apparently healthy college students (­4 male and 4 female) volunteered to participate in this study. The students height was 168.3 ± 8.7cm (range, 155-181cm), mass 76.8±19.5kg (range, 51.5-115.0kg) and age 21.5 ± 1.3y.o (range, 20-24y.o). Subjects attended the study on two occasions, with seven days interval between sessions. Randomly, the first session consisted of listening to audio-relaxation for 16 minutes. In the second session (session control), audio-relaxation was not played while the subjects waited for 16 minutes. The application of the treatment was performed in a room isolated from noise and light, just as it happened for the control condition, in which there was no treatment. In each session, the volunteers were evaluated before and after treatment, performing 20 free throws, 10 shots were performed at their own rhythm and the other 10 under pressure (at the sound of the whistle). RESULTS: According to the normal distribution in the values (p=0.200), a two-way repeated measures ANOVA was performed, in which it was found that there is no interaction between listening and not listening to audio-relaxation in the execution of ten free throws at their own rhythm and ten under pressure (p=0.510). CONCLUSION: Listening audio-relaxation does not significantly influence the effectiveness of the basketball free throws, it means that the people will not get improve their performance if use audio-relaxation technique

Antibacterial activity of copper salts against microorganisms isolated from chronic infected wounds

Indexación: Web of Science: Scopus; Scielo.Background: The antimicrobial activity of copper (Cu+2) is recognized and used as an antimicrobial agent. Aim: To evaluate the antimicrobial activity of copper against microorganisms obtained from chronic cutaneous wound infections. Material and Methods: Five chemical products that contained copper particles in their composition were tested (zeolite, silica, acetate, nitrate and nanoparticle of copper). The antimicrobial activity against antibiotic resistant strains usually isolated from chronic cutaneous wound infections was determined for two of the products with better performance in copper release. Results: The minimal inhibitory and minimal bactericidal concentrations of copper acetate and nitrate were similar, fluctuating between 400-2,000 mu g/ml. Conclusions: The studied copper salts show great potential to be used to control both gram positive and gram negative, antibiotic resistant bacteria isolated from wound infections.http://ref.scielo.org/jh7v9

Substantial morbidity and mortality associated with pandemic A/H1N1 influenza in Mexico, winter 2013-2014: Gradual age shift and severity.

BACKGROUND: A recrudescent wave of pandemic influenza A/H1N1 is underway in Mexico in winter 2013-14, following a mild 2012-13 A/H3N2 influenza season. Mexico previously experienced several waves of pandemic A/H1N1 activity in spring, summer and fall 2009 and winter 2011-2012, with a gradual shift of influenza-related hospitalizations and deaths towards older ages. Here we describe changes in the epidemiology of the 2013-14 A/H1N1 influenza outbreak, relative to previous seasons dominated by the A/H1N1 pandemic virus. The analysis is intended to guide public health intervention strategies in near real time. METHODS: We analyzed demographic and geographic data on hospitalizations with severe acute respiratory infection (SARI), laboratory-confirmed A/H1N1 influenza hospitalizations, and inpatient deaths, from a large prospective surveillance system maintained by the Mexican Social Security medical system during 01-October 2013 to 31-Jan 2014. We characterized the age and regional patterns of influenza activity relative to the preceding 2011-2012 A/H1N1 influenza epidemic. We also estimated the reproduction number (R) based on the growth rate of daily case incidence by date of symptoms onset. RESULTS: A total of 7,886 SARI hospitalizations and 529 inpatient-deaths (3.2%) were reported between 01-October 2013 and 31-January 2014 (resulting in 3.2 laboratory-confirmed A/H1N1 hospitalizations per 100,00 and 0.52 laboratory-confirmed A/H1N1-positive deaths per 100,000). The progression of daily SARI hospitalizations in 2013-14 exceeded that observed during the 2011-2012 A/H1N1 epidemic. The mean age of laboratory-confirmed A/H1N1 patients in 2013-14 was 41.1 y (SD=20.3) for hospitalizations and 49.2 y (SD=16.7) for deaths. Rates of laboratory-confirmed A/H1N1 hospitalizations and deaths were significantly higher among individuals aged 30-59 y and lower among younger age groups for the ongoing 2013-2014 epidemic, compared to the 2011-12 A/H1N1 epidemic (Chi-square test, P\u3c0.001). The reproduction number of the winter 2013-14 wave in central Mexico was estimated at 1.3-1.4 which is slightly higher than that reported for the 2011-2012 A/H1N1 epidemic. CONCLUSIONS: We have documented a substantial and ongoing increase in the number of A/H1N1-related hospitalizations and deaths during the period October 2013-January 2014 and a proportionate shift of severe disease to middle aged adults, relative to the preceding A/H1N1 2011-2012 epidemic in Mexico. In the absence of clear antigenic drift in globally circulating A/H1N1 viruses in the post-pandemic period, the gradual change in the age distribution of A/H1N1 infections observed in Mexico suggests a slow build-up of immunity among younger populations, reminiscent of the age profile of past pandemics

COPD classification models and mortality prediction capacity

Our aim was to assess the impact of comorbidities on existing COPD prognosis scores. Patients and methods: A total of 543 patients with COPD (FEV1 < 80% and FEV1/ FVC <70%) were included between January 2003 and January 2004. Patients were stable for at least 6 weeks before inclusion and were followed for 5 years without any intervention by the research team. Comorbidities and causes of death were established from medical reports or information from primary care medical records. The GOLD system and the body mass index, obstruction, dyspnea and exercise (BODE) index were used for COPD classification. Patients were also classified into four clusters depending on the respiratory disease and comorbidities. Cluster analysis was performed by combining multiple correspondence analyses and automatic classification. Receiver operating characteristic curves and the area under the curve (AUC) were calculated for each model, and the DeLong test was used to evaluate differences between AUCs. Improvement in prediction ability was analyzed by the DeLong test, category-free net reclassification improvement and the integrated discrimination index. Results: Among the 543 patients enrolled, 521 (96%) were male, with a mean age of 68 years, mean body mass index 28.3 and mean FEV1% 55%. A total of 167 patients died during the study follow-up. Comorbidities were prevalent in our cohort, with a mean Charlson index of 2.4. The most prevalent comorbidities were hypertension, diabetes mellitus and cardiovascular diseases. On comparing the BODE index, GOLDABCD, GOLD2017 and cluster analysis for pre-dicting mortality, cluster system was found to be superior compared with GOLD2017 (0.654 vs 0.722, P=0.006), without significant differences between other classification models. When cardiovascular comorbidities and chronic renal failure were added to the existing scores, their prognostic capacity was statistically superior (P<0.001). Conclusion: Comorbidities should be taken into account in COPD management scores due to their prevalence and impact on mortalit

Hydroacoustics as a tool to examine the effects of Marine Protected Areas and habitat type on marine fish communities

Abstract Hydroacoustic technologies are widely used in fisheries research but few studies have used them to examine the effects of Marine Protected Areas (MPAs). We evaluate the efficacy of hydroacoustics to examine the effects of closure to fishing and habitat type on fish populations in the Cabo Pulmo National Park (CPNP), Mexico, and compare these methods to Underwater Visual Censuses (UVC). Fish density, biomass and size were all significantly higher inside the CPNP (299%, 144% and 52% respectively) than outside in non-MPA control areas. These values were much higher when only accounting for the reefs within the CPNP (4715%, 6970% and 97% respectively) highlighting the importance of both habitat complexity and protection from fishing for fish populations. Acoustic estimates of fish biomass over reef-specific sites did not differ significantly from those estimated using UVC data, although acoustic densities were less due to higher numbers of small fish recorded by UVC. There is thus considerable merit in nesting UVC surveys, also providing species information, within hydroacoustic surveys. This study is a valuable starting point in demonstrating the utility of hydroacoustics to assess the effects of coastal MPAs on fish populations, something that has been underutilised in MPA design, formation and management

Energy, added sugar, and saturated fat contributions of taxed beverages and foods in Mexico

Objective. To estimate the dietary contribution of taxed beverages and foods. Materials and methods. Using 24-hour diet recall data from the Ensanut 2012 (n=10 096), we estimated the contribution of the items which were taxed in 2014 to the total energy, added sugar, and saturated fat intakes in the entire sample and by sociodemographic characteristics. Results. The contributions for energy, added sugar, and saturated fat were found to be 5.5, 38.1, and 0.4%, respectively, for the taxed beverages, and 14.4, 23.8, and 21.4%, respectively, for the taxed foods. Children and adolescents (vs. adults), medium and high socioeconomic status (vs. low), urban area (vs. rural), and North and Center region (vs. South) had higher energy contribution of taxed beverages and foods. The energy contribution was similar between males and females. Conclusions. These taxes covered an important proportion of Mexicans’ diet and therefore have the potential to improve it meaningfully

Chronic obstructive pulmonary disease subtypes. transitions over time

Background Although subtypes of chronic obstructive pulmonary disease are recognized, it is unknown what happens to these subtypes over time. Our objectives were to assess the stability of cluster-based subtypes in patients with stable disease and explore changes in clusters over 1 year. Methods Multiple correspondence and cluster analysis were used to evaluate data collected from 543 stable patients included consecutively from 5 respiratory outpatient clinics. Results Four subtypes were identified. Three of them, A, B, and C, had marked respiratory profiles with a continuum in severity of several variables, while the fourth, subtype D, had a more systemic profile with intermediate respiratory disease severity. Subtype A was associated with less dyspnea, better health-related quality of life and lower Charlson comorbidity scores, and subtype C with the most severe dyspnea, and poorer pulmonary function and quality of life, while subtype B was between subtypes A and C. Subtype D had higher rates of hospitalization the previous year, and comorbidities. After 1 year, all clusters remained stable. Generally, patients continued in the same subtype but 28% migrated to another cluster. Together with movement across clusters, patients showed changes in certain characteristics (especially exercise capacity, some variables of pulmonary function and physical activity) and changes in outcomes (quality of life, hospitalization and mortality) depending on the new cluster they belonged to Conclusions Chronic obstructive pulmonary disease clusters remained stable over 1 year. Most patients stayed in their initial subtype cluster, but some moved to another subtype and accordingly had different outcomes