A price based load balancing scheme for multi-operator wireless access networks

We study a load balancing strategy, based on the price offered by the base stations to the end-users who are willing to establish a connection. The proposed scheme is compared with a pure load balancing procedure, in a scenario comprising two different operators.We study the impact of modifying the price offered by the base stations, in terms of the achieved load balancing, as well as considering the revenue obtained by the operators. Furthermore, we also enhance the two former access selection schemes, by incorporating the willingness of reducing the number of handovers, so as to analyze the impact over this particular parameter, and over all the previous results. The whole work is conducted over a proprietary event-based simulation tool, which offers the required degree of flexibility and low computational overhead.Preprin

On the equilibrium of pricing assignment for heterogeneous wireless access networks

Next generation networks and service providers are rapidly evolving in order to satisfy the demands of an increasing number of users. Nowadays, one of the most relevant research lines in the Heterogeneous Wireless Access Networks realm is the use of procedures and mechanisms so as to provide intelligence to the network, with the main goal of optimizing its performance. Furthermore, mobile communication users are becoming more demanding, and thus it becomes essential for the providers to be able to offer a competitive value for money. This paper pursues the objective of obtaining, from an analytical perspective, the optimum price assignment strategy according to the characteristics of a particular scenario, analyzing the improvement attained with such optimum pricing policy as compared to a more traditional one. Game theory techniques, which are gathering the interest within the communications scientific community, are used for the analysis.Preprin

Non-Adherence to Malaria Chemo-Prophylaxis in Travelers: Mind to the Care Gap!

Background: Travelers are at risk of contracting malaria when moving to endemic areas. Yet, despite effective malaria chemoprophylaxis, imported cases of malaria still occur worldwide. Indeed, some studies have shown a varied adherence level; consequently, a traveler care gap could occur. Methods: A prospective cohort study was carried out in 2017 to evaluate the rate of malaria chemoprophylaxis adherence among Spanish travelers. Results: A post-travel questionnaire was completed by 402 travelers to malaria endemic areas that were prescribed chemoprophylaxis: 67 (16.7%) did not take any dose of chemoprophylaxis and 41 (10.2%) had not even carried it while travelling abroad. The adherence of chemoprophylaxis was 68,7% of travelers, being statistically different according to travel duration, onset of adverse events and type of drug prescribed. The non-adherent travelers reported not continuing with administration mainly because of forgetfulness, fear of side effects and low perceived risk because itinerary changes. Regarding the onset of the medication's secondary adverse events, one in three (35.2%) reported at least one, being more frequent among patients that took mefloquine than atovaquone-proguanil (p=0.01). The main adverse events reported by chemoprophylaxis users were gastrointestinal or sleeping disorders. Conclusions: The suboptimal compliance of chemoprophylaxis is a major lost opportunity to achieve malaria prevention, so it is an important contributor to the traveler care gap

Stand-by emergency treatment (SBET) of malaria in Spanish travellers: a cohort study

Background: Among strategies for malaria prevention, stand-by emergency treatment (SBET) is a possible approach, but scarce evidences exists investigating travellers' adherence and behaviours toward its use; therefore, the presented study aimed to determine travellers' compliance toward the SBET when prescribed in travel clinics. Methods: A prospective cohort study was performed at the Travel Health Clinic of the Hospital Universitari de Bellvitge, Barcelona, Spain, during 2017. The research was planned on survey-based design, using pre- and post-travel questionnaires. Results: In the study period, of 5436 subjects who attended the HUB Travel Medicine Clinic, 145 travellers to malariaendemic areas were prescribed SBET, and all patients agreed to participate in the study by completing the pre-travel questionnaire. Approximately half the participants were women (n=75, 51.7%), and the median age of all travellers was 29 years (range 13-57), mainly travelling to South-East Asia (n=69, 47.6%), with Indonesia and the Philippines as the most popular destinations. The length of travels had a median duration of 29 days (range 10-213). Of the recruited participants, 98 replied to the online post-travel survey, reaching a response rate of 67.6%. A total of 62.2% of travellers to which SBET was prescribed did not buy and carry drugs while travelling abroad. No participants' baseline or travel characteristic was shown to be signifcantly associated (p>0.05) with this behaviour. Four women (4.1%) experienced fever and self-administered SBET, without seeking medical attention. No malaria cases were observed. Conclusions: This cohort study addressed travellers' adherence and behaviour toward SBET, highlighting an incorrect use of the emergency treatment in case of presumptive malaria symptoms. This should be taken into account during pre-travel consultation, since the success of this strategy for malaria prevention depends on travellers' strong adher‑ ence to it

Relationship between smoking and acute mountain sickness: a meta-analysis of observational studies

Aims. Previous epidemiological investigations of the relationship between smoking and acutemountain sickness (AMS) risk yielded inconsistent findings.Therefore, a meta-analysis of observational studies was performed to determine whether smoking is related to the development of AMS. Methods. Searches were performed on PubMed, Scopus, Embase, and Web of Science for relevant studies that were published before November 2016 reporting smoking prevalence and AMS. Two evaluators independently selected studies, extracted data, and assessed study quality.Thepooled relative risks (RRs) and 95% confidence intervals (CIs) were obtained using random-effects models. Subgroup analyses were performed according to the type of participant, altitude, and study design. Results. A total of 11 observational studies involving 7,106 participants, 2,408 of which had AMS, were eligible for inclusion in this meta-analysis. The summary RR for AMS comparing smokers to nonsmokers was 1.02 (95% CI: 0.83 to 1.26). Specific analyses for altitude, type of participant, and study design yielded similar results.There was significant heterogeneity for all studies ( = 37.43; < 0.001; 2 = 73%, 95% CI: 51% to 85%). No publication bias was observed (Egger's test: = 0.548, Begg's test: = 0.418). Conclusions.The meta-analysis indicates that no difference was found in AMS risk with regard to smoking status

Planteamiento y resultados iniciales de un experimento sobre el uso de un software educativo en la asignatura de farmacología veterinaria

El presente trabajo se desarrolló en la Facultad de Medicina Veterinaria de la Universidad de Granma (Cuba) en el período correspondiente al primer semestre del curso académico 2004 - 2005. En el mismo se expone el diseño de un experimento aplicado a los estudiantes del tercer año de la carrera, basado en la inclusión de un software educativo (DosisCalculator v2.0) en el proceso docente educativo de la asignatura de Farmacología Veterinaria, con el objetivo de utilizarlo para el desarrollo de las clases prácticas de cálculo de dosis de medicamentos. Así como la exposición de los resultados obtenidos en la primera fase del proyecto, los cuales mostraron una tendencia a la mejora de la calidad de los conocimientos adquiridos en un 10%, además de lograr una mayor uniformidad y estabilidad de las calificaciones.Eje: Educación universitaria: Experiencias uso NTICRed de Universidades con Carreras en Informática (RedUNCI

Planteamiento y resultados iniciales de un experimento sobre el uso de un software educativo en la asignatura de farmacología veterinaria

El presente trabajo se desarrolló en la Facultad de Medicina Veterinaria de la Universidad de Granma (Cuba) en el período correspondiente al primer semestre del curso académico 2004 - 2005. En el mismo se expone el diseño de un experimento aplicado a los estudiantes del tercer año de la carrera, basado en la inclusión de un software educativo (DosisCalculator v2.0) en el proceso docente educativo de la asignatura de Farmacología Veterinaria, con el objetivo de utilizarlo para el desarrollo de las clases prácticas de cálculo de dosis de medicamentos. Así como la exposición de los resultados obtenidos en la primera fase del proyecto, los cuales mostraron una tendencia a la mejora de la calidad de los conocimientos adquiridos en un 10%, además de lograr una mayor uniformidad y estabilidad de las calificaciones.Eje: Educación universitaria: Experiencias uso NTICRed de Universidades con Carreras en Informática (RedUNCI

Efecto de la profundidad del suelo en Rottboellia cochinchinensis (Lour) Clayton en caña de azúcar (Saccharum officinarum L.)

Four sugarcane fields with different soil textures (clay loam, sandy loam, clay and loam) were sampled. All fields showed R. cochinchinensis populations with at least 75-150 plants/m2. The number of plants of this weed in 0.25 m2 was determined separately in the microhabitats: rows and between rows. The depth at which each plant emerged was measured. Based on depth emergence, each plant was distributed in one of the next categories: 0, >0-2.5, >2.5-5.0, >5.0-10 and >10.0-15.0 cm. In addition, under greenhouse conditions, seeds were seeded in pots at the maximum depth of each category in order to evaluate the effect of soil depth. Finally, the effect of light and darkness on seed germination were evaluated in Petri dishes under laboratory conditions. In the field evaluations most of the plants emerged from >0-2.5 cm. The second most common category was >2.5-5.0 cm. It seems that those depths provide optimum conditions for germination. There were no differences regarding soil texture or microhabitats. In the greenhouse experiment, the largest germination was observed at 0 cm due to light exposure in this treatment. This was confirmed in the laboratory where light treatment showed also the largest germination. Control strategies that keep the seeds of this species above ground will reduce the number of new seeds in the seed bank and avoid optimum field conditions for its germination. If such strategies include efforts to reduce the seed production of those plants that are able to become established, it could be possible to significantly reduce the seed bank, therefore, it would be easier to control the population of this weed.Se muestrearon cuatro lotes con diferente textura de suelo, sembrados con caña de azúcar durante cuatro años consecutivos. El lote A con suelo franco arcilloso, el lote B con suelo franco arenoso, el lote C con suelo arcilloso y el lote D con suelo franco. Se seleccionaron lotes con una población de R. cochinchinensis de 75 a 150 plantas/m2. Se contó el número de plantas de la maleza en un área de 0,25 m2, en dos micro-hábitats: el surco y entre-surco. A cada planta se le escarbó el suelo que la rodeaba hasta encontrar la semilla de la que provenía y se midió la profundidad a la que ésta se encontró, para luego determinar qué porcentaje del total de plantas contabilizadas provenía de semillas localizadas en cada uno de los siguientes estratos: 0,0; >0,0 a 2,5; >2,5 a 5,0; >5,0 a 10 y >10,0 a 15,0 cm de profundidad. Además, se evaluó en invernadero el efecto de cada profundidad de los estratos citados. A nivel de laboratorio y en platos Petri, se evaluó el efecto de la luz y la oscuridad sobre la germinación de la semilla de R. cochinchinensis. Se encontró que la mayoría de las plantas en campo provenían de semillas que se encontraban de >0 a 2,5 cm, seguido por aquellas que estaban de >2,5 a 5,0 cm donde se dieron las mejores condiciones para la germinación. No se observaron diferencias entre los tipos de suelo o los micro-hábitats evaluados. En invernadero el tratamiento a 0,0 cm fue el que mostró la mayor germinación y esto fue producto de la exposición a la luz, lo cual se corroboró en el estudio en laboratorio donde el tratamiento con luz presentó también, la mayor germinación

Efecto de tipos de labranza sobre la población de malezas en caña de azúcar (Saccharum officinarum L.)

Experiments were conducted in two sugarcane fields, one with low weed pressure (plot 1) and the other with high weed pressure (plot 2). Four treatments were established in each study: green harvest that left plant mulch on soil surface (VCR), green harvest without plant mulch on soil surface (VSR), burning the crop before harvest without soil disturbance (QSL) and burning the crop before harvest with soil disturbance (QCL). Evaluations were made 75 days after harvest. The evaluations were conducted separately in rows and between rows. In addition, sugarcane population and height were measured. Differences in weed populations were not observed for the field with low weed pressure (plot 1). In the field with high weed pressure (plot 2), weeds were favored by burning and soil disturbance caused by fertilizer incorporation. Thus the treatments QSL and QCL showed the highest percentage of surface coverage. Also, the QCL treatment had the greatest weed populations resulting in reduced sugarcane population and height. Purple nutsedge (Cyperus rotundus L.) and itchgrass (Rottboellia cochinchinensis (Lour.) Clayton) had the greatest percentage surface coverage, especially in QCL. Weed populations were larger in rows than between rows. Apparently in rows, weeds found better conditions for germination and nutrient uptake.En dos lotes de caña de azúcar, uno con baja presión de malezas (lote 1) y otro con alta (lote 2), se evaluaron cuatro tratamientos: cosecha en verde con rastrojo (VCR), cosecha en verde sin rastrojo (VSR), cosecha con quema sin labranza (QSL) y cosecha con quema con labranza (QCL). Se evaluó las especies de malezas así como su población y cobertura del suelo hasta los 75 días después de cosecha, tanto en el surco como en el entre-surco. Además, se evaluó la altura y el número de tallos del cultivo por metro lineal. No se observaron diferencias entre las poblaciones de malezas en el lote 1. En el lote 2 las malezas se vieron beneficiadas por la labranza y por la quema; así los tratamientos QSL y QCL mostraron las mayores coberturas, siendo este último el que presentó las poblaciones más altas y en el que se dió una disminución en el número y altura de tallos de la caña de azúcar. Cyperus rotundus L. y Rottboellia cochinchinensis (Lour) Clayton presentaron las mayores coberturas, especialmente en QCL. En el surco se dio un desarrollo superior de las poblaciones de malezas, al observado en el entre-surco, ya que presentó mejores condiciones de germinación y disponibilidad de nutrimentos