2,206 research outputs found
Globalización, funcionalidad económica y estructura urbana en Guadalajara, 1990-2000
Este trabajo tiene como propósito analizar las transformaciones que experimentaron la funcionalidad económica y la estructura urbana de la zona conurbada de Guadalajara (ZCG) en la última década del siglo XX, en el marco del proceso de globalización. Partimos del supuesto de que la integración de la economía de esta metrópoli a dicho fenómeno contribuye a que asuma las funciones de plataforma de exportación de la industria globalizada y de centro de distribución regional de mercancías producidas en otros países1. Buscamos hacer una aportación distinta a la “nueva geografía urbana” (Sassen 1999), en la que la ciudad global se ha convertido en el epicentro y escenario protagónico de la globalización. En este trabajo el objeto de estudio no es la ciudad global, sino una de ellas que ocupan una posición periférica y tienen una cobertura subnacional y local, como ocurre con la ZCG. Aquí evaluaremos el alcance económico y territorial de dicho fenómeno en una ciudad de la periferia económica.Peer Reviewe
Efecte d’un programa d’intervenció basat en l’expressió corporal sobre la millora conceptual d’hàbits saludables en nens de sisè curs
S’ha portat a terme una intervenció per a la millora conceptual d’hàbits saludables a través de l’Expressió Corporal en alumnes de 6è de primària. El treball esmentat es va realitzar durant 10 sessions aplicades al grup experimental; es va utilitzar la indagació com a principal tècnica d’ensenyament, i també un full complementari de treball sobre el contingut conceptual desenvolupat en la sessió. El grup control va realitzar allò que hi havia previst a la programació d’aula aprovada en el projecte educatiu del centre. El coneixement conceptual sobre hàbits saludables va ser avaluat mitjançant un qüestionari de 57 preguntes. Els resultats van mostrar un augment altament significatiu del nivell de coneixement del Grup Experimental (p < 0,0001) en passar de 34,36 ± 6,23 en el pretest a 48,86 ± 4,26 en el posttest i mantenir-se en 48,14 ± 2,68 en el retest. Encara que el Grup Control també va experimentar un increment significatiu (p < 0,01), en passar de 33,79 ± 3,70 en el pretest a 37,71 ± 3,50 en el posttest i baixar a 34,79 ± 3,59 en el retest. Els resultats obtinguts corroboren la idoneïtat del programa d’intervenció. Es conclou que l’Expressió corporal pot ser un contingut adequat per millorar el coneixement sobre hàbits de vida saludables
Implementación del mantenimiento centrado en la confiabilidad (RCM) en Schlumberger Wireline
Publicación a texto completo no autorizada por el autorDesarrolla un plan para el proceso de implementación del servicio de mantenimiento centrado en la confiabilidad (RCM) a los equipos, con la finalidad de minimizar sus fallas, reducir el costo del mantenimiento y la racionalización de los equipos en las operaciones. Establece el criterio para iniciar la implementación del RCM en Schlumberger Wireline (SLB-WL). Selecciona una herramienta de SLB-WL a la que se le aplicará el proceso RCM y que servirá de piloto para replicarlo dentro de la organización. Analiza los modos de fallas de la herramienta, a partir de los incidentes reportados y de los altamente probables que puedan ocurrir. Elabora las instrucciones de trabajo estándar SWI (Standard Work Instruction) para el mantenimiento de la herramienta seleccionada.Trabajo de suficiencia profesiona
Teaching and Learning of Mathematics through CLIL, CBI, or EMI—A Systematic Literature Review
This study provides a systematic literature review of research in the field of teaching and learning mathematics through Content and Language Integrated Learning (CLIL), Content-Based Instruction (CBI), and English Medium Instruction (EMI). The review aims to examine the most relevant literature with a focus on mathematics and CLIL, CBI, or EMI in Scopus and Web of Science per the Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines. Based on 151 sources, 52 papers were selected according to predefined selection criteria. The papers were analysed and coded according to the following categories: (1) geographical productivity, (2) diachronic productivity growth, (3) main objectives, (4) methodology, and research design, (5) variables and measurement instruments, (6) context and sample details, and (7) main findings. The results reveal that most of the research analysed has been carried out in the Asian continent, followed by Europe. The analysis of diachronic productivity shows that the study of the application of CLIL, CBI, and EMI programs in the teaching-learning process of mathematics has notably increased in recent years, especially in the last triennium (2020–2022). Regarding the objectives of the selected corpus, the majority aimed at teaching practices and learning processes, and outcomes in mathematics and language proficiency in CLIL, CBI, and/or EMI classrooms. The corpus analysed fits within one or more of the following categories: empirical, qualitative, descriptive, correlational, and cross-sectional. The samples utilized in different studies differ significantly, both in terms of quantity –ranging from one person to 700– and in the educational level being studied, which would be primary, secondary, or tertiary education. The main variables studied in the corpus focus on mathematical competence, language proficiency, teaching practices, teacher training, science competence, and teachers’ perceptions. The most widely used instruments have been objective tests, such as questionnaires, together with standardized tests to measure some aspects related to mathematical competence and language proficiency. They are followed by an analysis of documents (academic records, teaching materials, official documents...), participant or non-participant observation, interviews, and video and audio recordings. In summary, in the scientific literature analysed, a positive or neutral view predominates on the effects of the CLIL, CBI, and EMI approaches on the learning of mathematics and the L2. This can be due to methodological issues fundamentally related to the methodology, research design, sample, and measurement instruments. Thus, we must highlight that some of the results from the selected papers must be interpreted with caution. Taking this factor into consideration, further comparative studies on a wider scale are required to examine thoroughly the effects of CLIL, CBI, and EMI on the teaching and learning of mathematics in an L2. Besides, it is important to study in greater depth the different levels of language acquisition since the research analysed shows that these have not been sufficiently addressed in the mathematical field of knowledge
General Architecture for Development of Virtual Coaches for Healthy Habits Monitoring and Encouragement
Good health is the result of a healthy lifestyle, where caring about physical activity
and nutrition are key concerns. However, in today’s society, nutritional disorders are becoming
increasingly frequent, affecting children, adults, and elderly people, mainly due to limited nutrition
knowledge and the lack of a healthy lifestyle. A commonly adopted therapy to these imbalances
is to monitor physical activity and daily habits, such as recording exercise or creating custom meal
plans to count the amount of macronutrients and micronutrients acquired in each meal. Nowadays,
many health tracking applications (HTA) have been developed that, for instance, record energy
intake as well as users’ physiological parameters, or measure the physical activity during the day.
However, most existing HTA do not have a uniform architectural design on top of which to build
other applications and services. In this manuscript, we present system architecture intended to serve
as a reference architecture for building HTA solutions. In order to validate the proposed architecture,
we performed a preliminary evaluation with 15 well recognized experts in systems and software
architecture from different entities around world and who have estimated that our proposal can
generate architecture for HTA that is adequate, reliable, secure, modifiable, portable, functional, and
with high conceptual integrity. In order to show the applicability of the architecture in different
HTA, we developed two telemonitoring systems based on it, targeted to different tasks: nutritional
coaching (Food4Living) and physical exercise coaching (TrainME). The purpose was to illustrate the
kind of end-user monitoring applications that could be developed.
Keywords: telemonitoring; healthy habits; virtual coaches; system
Assessing attention deficit by binocular rivalry
Objective: To determine whether the frequency and duration of the periods of suppression of a percept in a binocular rivalry (BR) task can be used to distinguish between subjects with attention deficit hyperactivity disorder (ADHD) and controls. Method: 122 participants (6 to 15 years) were assigned to three groups: ADHD Combined (ADHD-C), ADHD-Predominantly Inattentive (ADHD-I) and controls. They each performed a BR task and two measures were recorded: alternation rate and duration of exclusive dominance periods. Results: ADHD-C group presented fewer alternations and showed greater variability than did the control group; results for the ADHD-I group being intermediate between the two. The duration of dominance periods showed a differential profile: in control group it remained stable over time, whereas in the clinical groups it decreased logarithmically as the task progressed. Conclusions: The differences between groups in relation to the BR indicators can be attributed to the activity of involuntary inhibition
Psychometric properties of a test for ADHD based on binocular rivalry
The psychometric properties of a Binocular Rivalry (BR)-based test on a group of 159 participants (57 with attention deficit hyperactivity disorder, ADHD) aged between 6 and 15 years are presented. Two factors, which explained 56.82% of the variance, were obtained by exploratory factor analysis: (a) Alternations and Duration of exclusive dominances, and (b) Decision time. Reliability was excellent (Cronbach's á = .834 and .884). The ADHD group showed fewer alternations and longer duration of dominances and decision time than the control group. Correlations between measures of BR, IQ, working memory, and processing speed of the WISC-IV, and ADHD symptoms, assessed by parents and teachers, ranged between low and medium
Complex interactions in microbial food webs : stoichiometric and functional approaches
The food web structure in some high mountain lakes deviates from the established tendency of high heterotrophic bacteria: phytoplankton biomass ratios in oligotrophic ecosystems. Thus, the microbial food web in La Caldera Lake is weakly developed, and bacteria constitute a minor component of the plankton community in terms of abundance, biomass and production. Autotrophic picoplankton is absent, and heterotrophic microbial food web is weakly developed compared to a grazing chain dominated by calanoid copepods and a phytoplankton community mainly composed of mixotrophic flagellates. In order to explain the singular food web structure of this lake, functional, stoichiometric and taxonomical approaches are followed to assess, on various temporal and spatial scales, the relevance of stressful abiotic factors (ultraviolet solar radiation and P-limitation) on the structure and functioning of this ecosystem. P-availability was the main factor controlling the algal biomass whereas bacterial P- limitation was a transient phenomenon. The algae-bacteria relationship was predominately commensalistic. In contrast to algae, full-sunlight radiation had no negative effect on bacterial growth but rather enhanced bacterial dependence on the carbon released by algae. The prevalence of the commensalistic-mutualistic relationship and the development of a more complex microbial food web were related to the stoichiometry of algae and bacteria (N:P ratios). The microbial food web only developed at balanced algal and bacterial N:P ratios, with the appearance of ciliates after a nutrient pulse. However, mixotrophic algae dominated the planktonic community under P-deficit conditions, and they were the main factor controlling bacterioplankton. Their regulatory effect has a dual nature: (i) a resource-based control, where bacteria depend on the photosynthetic carbon released by algae, i.e., a commensalistic interaction ("without you I cannot live"); and (ii) a predatory control, where bacteria is a prey for mixotrophs ("with you I die"). Hence, the niche of microheterotrophs (nanoflagellates and ciliates) is occupied by mixotrophs, and there is a resulting simplification of the planktonic structure. With respect to the carbon cycle, mixotrophic bacterivory constitutes a "by-pass" for the flux of C towards the grazing chain, precluding the development of a complex heterotrophic microbial food web. Mixotrophs thereby improve the energetic transfer efficiency in high mountain lakes through a reduction in the number of trophic levels. Antagonistic effects of UVR x P interactions on the algae-bacteria relationship were caused by an enhancement of dual (resource and predation) control. Based on these results, an alternative model for the flux of C in autotrophic high mountain lakes has been proposed.La estructura de la red trófica en algunos lagos de alta montaña, se aleja de los patrones establecidos para ecosistemas oligotróficos que proponen el predominio de la red trófica microbiana sobre la cadena de pastoreo. Así, en la laguna de La Caldera las bacterias son el componente minoritario de la comunidad planctónica en términos de abundancia, biomasa y producción. El picoplancton autótrofo está ausente y la red microbiana heterotrófica se encuentra escasamente desarrollada frente a una cadena de pastoreo dominada por copépodos calanoides y algas mixotróficas. Para comprender los mecanismos que determinan esta estructura trófica hemos seguido diferentes aproximaciones de análisis: funcional, estequiométrica y taxonómica sobre distintas escalas espaciales y temporales, en relación con los principales factores de estrés abiótico (radiación ultravioleta y limitación por fósforo) que controlan el funcionamiento de los ecosistemas de alta montaña. Nuestros resultados indican que la disponibilidad de fósforo, de forma generalizada, controla la biomasa algal y de manera transitoria la bacteriana, estableciéndose entre ambas comunidades una relación comensalista. La radiación solar completa no afecta negativamente el desarrollo de las bacterias y si el de las algas y potencia la relación de dependencia por el carbono orgánico (comensalismo) entre algas y bacterias. El predominio de la relación comensalista-mutualista y el desarrollo del bucle microbiano esta relacionado con la estequiometría (razón N:P) de algas y bacterias. Así, sólo cuando la razón N:P de algas y bacterias es equilibrada para crecer, un pulso de nutrientes permite el desarrollo del bucle microbiano. En condiciones naturales de déficit de P, sin embargo, existe un predominio de "algas" con metabolismo mixotrófico. Las algas mixotróficas ejercen un efecto regulador dual sobre las bacterias que denominamos Ni contigo ni sin ti, (i) control por depredación, donde las bacterias son consumidas por algas mixotróficas ("contigo me muero"), (ii) control basado en los recursos estableciéndose una relación de dependencia de las bacterias sobre del carbono liberado por las algas ("sin ti no puedo vivir"). La mixotrofia supone un simplificación en la cadena trófica microbiana, donde los mixótrofos ocupan el nicho potencial de nanoflagelados y ciliados. Desde un punto de vista energético implica un cortocircuito en el flujo de energía y un incremento en la eficiencia de transferencia energética en ecosistemas ultraoligotróficos y con alta dosis de radiación ultravioleta (RUV). Los efectos de la interacción entre RUV y pulsos de P tienen un efecto antagónico sobre la interacción alga-bacteria, intensificando la interacción comensal-depredadora. A partir de los resultados obtenidos proponemos un modelo alternativo de flujo de energía para ecosistemas autotróficos de alta montaña
Antibacterial Effect of Functionalized Polymeric Nanoparticles on Titanium Surfaces Using an In Vitro Subgingival Biofilm Model
This research was funded by the Ministry of Economy and Competitiveness (MINECO) and the European Regional Development Fund (FEDER), grant number (PID2020-114694RB-I00 MINECO/AEI/FEDER/UE). M. Toledano-Osorio holds a FPU fellowship from the Ministry of Universities (FPU20/00450).This investigation aimed to evaluate the antibacterial effect of polymeric nanoparticles
(NPs), functionalized with calcium, zinc, or doxycycline, using a subgingival biofilm model of six
bacterial species (Streptococcus oralis, Actinomyces naeslundii, Veillonela parvula, Fusobacterium nucleatum,
Porphyromonas gingivalis, and Aggregatibacter actinomycetemcomitans) on sandblasted, large grit, acidetched
titanium discs (TiDs). Undoped NPs (Un-NPs) or doped NPs with calcium (Ca-NPs), zinc
(Zn-NPs), or doxycycline (Dox-NPs) were applied onto the TiD surfaces. Uncovered TiDs were used
as negative controls. Discs were incubated under anaerobic conditions for 12, 24, 48, and 72 h. The
obtained biofilm structure was studied by scanning electron microscopy (SEM) and its vitality and
thickness by confocal laser scanning microscopy (CLSM). Quantitative polymerase chain reaction
of samples was used to evaluate the bacterial load. Data were evaluated by analysis of variance
(p < 0.05) and post hoc comparisons with Bonferroni adjustments (p < 0.01). As compared with
uncovered TiDs, Dox-NPs induced higher biofilm mortality (47.21% and 85.87%, respectively) and
reduced the bacterial load of the tested species, after 72 h. With SEM, scarce biofilm formation was
observed in Dox-NPs TiDs. In summary, Dox-NPs on TiD reduced biofilm vitality, bacterial load, and
altered biofilm formation dynamics.Spanish GovernmentEuropean Commission PID2020-114694RB-I00 MINECO/AEI/FEDER/UEMinistry of Universities FPU20/0045
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