509 research outputs found
Thermophilic and mesophilic temperature phase anaerobic codigestion (TPAcD) compared with single-stage co-digestion of sewage sludge and sugar beet pulp lixiviation
The performance of temperature phase anaerobic co-digestion (TPAcD) for sewage sludge and sugar beet
pulp lixiviation (using the process of exchanging the digesting substrate between spatially separated
thermophilic and mesophilic digesters) was tested and compared to both single-stage mesophilic and
thermophilic anaerobic co-digestion. Two Hydraulic Retention Times (HRT) were studied in the thermophilic stage of anaerobic digestion in two temperature phases, maintaining the optimum time of the
mesophilic stage at 10 days, obtained as such in single-stage anaerobic co-digestion. In this way, we
obtained the advantages of both temperature regimes.
Volatile solids removal efficiency from the TPAcD system depended on the sludge exchange rate, but
fell within the 72.6e64.6% range. This was higher than the value of 46.8% obtained with single-stage
thermophilic digestion and that of 40.5% obtained with mesophilic digestion. The specific methane
yield was 424e468 ml CH4 per gram of volatile solids removed, similar to that of single-stage mesophilic
anaerobic digestion. The increase in microbial activity inside the reactor was directly proportional to the
organic loading rate (OLR) (or inversely proportional to the HRT) and inversely proportional to the size of
the microbial population in single-stage anaerobic co-digestion systems
Photosynthetic active radiation, solar irradiance and the CIE standard sky classification
Plant growth is directly related to levels of photosynthetic photon flux density, Qp.
The improvement of plant-growth models therefore requires accurate estimations of the Qp parameter
that is often indirectly calculated on the basis of its relationship with solar irradiation, RS, due to
the scarcity of ground measurements of photosynthetic photon flux density. In this experimental
campaign in Burgos, Spain, between April 2019 and January 2020, an average value of the Qp/Rs ratio
is determined on the basis of measurements at ten-minute intervals. The most influential factor in the
Qp/Rs ratio, over and above any daily or seasonal pattern, is the existence of overcast sky conditions.
The CIE standard sky classification can be used to establish an unequivocal characterization of the
cloudiness conditions of homogeneous skies. In this study, the relation between the CIE standard sky
type and Qp/Rs is investigated. Its conclusions were that the Qp/Rs values, the average of which
was 1.93 0.15 mol J�����1, presented statistically significant di erences for each CIE standard sky
type. The overcast sky types presented the highest values of the ratio, while the clear sky categories
presented the lowest and most dispersed values. During the experimental campaign, only two
exceptions were noted for covered and partial covered sky-type categories, respectively, sky types
5 and 9. Their values were closer to those of categories classified as clear sky according to the CIE
standard. Both categories presented high uniformity in terms of illumination.Spanish Ministry of Science and Innovation, grant number RTI2018-098900-B-I00 and Consejería de Educación, Junta de Castilla y León, grant number BU021G1
Solar Ultraviolet Irradiance Characterization under All Sky Conditions in Burgos, Spain
Solar Ultraviolet Radiation (UVR), which is identified as a major environmental health
hazard, is responsible for a variety of photochemical reactions with direct effects on urban and
aquatic ecosystems, human health, plant growth, and the deterioration of industrial systems. Ground
measurements of total solar UVR are scarce, with low spatial and temporal coverage around the
world, which is mainly due to measurement equipment maintenance costs and the complexities of
equipment calibration routines; however, models designed to estimate ultraviolet rays from global
radiation measurements are frequently used alternatives. In an experimental campaign in Burgos,
Spain, between September 2020 and June 2022, average values of the ratio between horizontal global
ultraviolet irradiance (GHUV) and global horizontal irradiance (GHI) were determined, based on
measurements at ten-minute intervals. Sky cloudiness was the most influential factor in the ratio,
more so than any daily, monthly, or seasonal pattern. Both the CIE standard sky classification and the
clearness index were used to characterize the cloudiness conditions of homogeneous skies. Overcast
sky types presented the highest values of the ratio, whereas the clear sky categories presented
the lowest and most dispersed values, regardless of the criteria used for sky classification. The
main conclusion, for practical purposes, was that the ratio between GHUV and GHI can be used to
model GHUV.This research was funded by the Spanish Ministry of Science and Innovation, grant numbers RTI2018-098900-B-I00 and TED2021-131563B-I00, and Junta de Castilla y León, grant numbers INVESTUN/19/BU/0004 and INVESTUN/22/BU/0001
Assessment of the effects of decision aids about breast cancer screening: a systematic review and meta-analysis
Objective: The aim of this systematic review and meta-analysis of randomised controlled trials (RCTs) and observational studies is to assess the effect of decision aids (DAs) in women aged 50 and below facing the decision to be screened for breast cancer. Setting: Screening for breast cancer. Intervention: DAs aimed to help women make a deliberative choice regarding participation in mammography screening by providing information on the options and outcomes. Eligible studies: We included published original, non-pilot, studies that assess the effect of DAs for breast cancer screening. We excluded the studies that evaluated only participation intention or actual uptake. The studies' risk of bias was assessed with the Cochrane Collaboration's tool for RCTs and the National Institutes of Health Quality Assessment Tool for non-RCTs. Primary and secondary outcomes: The main outcome measures were informed choice, decisional conflict and/or confidence, and knowledge. Secondary outcomes were values, attitudes, uncertainty and intention to be screened. Results: A total of 607 studies were identified, but only 3 RCTs and 1 before-after study were selected. The use of DAs increased the proportion of women making an informed decision by 14%, 95% CI (2% to 27%) and the proportion of women with adequate knowledge by 12%, 95% CI (7% to 16%). We observed heterogeneity among the studies in confidence in the decision. The meta-analysis of the RCTs showed a significant decrease in confidence in the decision and in intention to be screened. Conclusions: Tools to aid decision making in screening for breast cancer improve knowledge and promote informed decision; however, we found divergent results on decisional conflict and confidence in the decision. Under the current paradigm change, which favours informed choice rather than maximising uptake, more research is necessary for the improvement of DAs
Extension of PAR Models under Local All-Sky Conditions to Different Climatic Zones
Four models for predicting Photosynthetically Active Radiation (PAR) were obtained through MultiLinear Regression (MLR) and an Artificial Neural Network (ANN) based on 10 meteorological indices previously selected from a feature selection algorithm. One model was developed for all sky conditions and the other three for clear, partial, and overcast skies, using a sky classification based on the clearness index (kt). The experimental data were recorded in Burgos (Spain) at ten-minute intervals over 23 months between 2019 and 2021. Fits above 0.97 and Root Mean Square Error (RMSE) values below 7.5% were observed. The models developed for clear and overcast sky conditions yielded better results. Application of the models to the seven experimental ground stations that constitute the Surface Radiation Budget Network (SURFRAD) located in different Köppen climatic zones of the USA yielded fitted values higher than 0.98 and RMSE values less than 11% in all cases regardless of the sky type.This research was funded by the Spanish Ministry of Science and Innovation, grant number RTI2018-098900-B-I00, and Consejería de Empleo e Industria, Junta de Castilla y León, grant number INVESTUN/19/BU-0004
Modelling Photosynthetic Active Radiation (PAR) through meteorological indices under all sky conditions
In this study, ten-minute meteorological data-sets recorded at Burgos, Spain, are used to develop models of Photosynthetic Active Radiation () following two different procedures: multilinear regression and Artificial Neural Networks. Ten Meteorological Indices (MIs) are chosen as inputs to the models: clearness index (), diffuse fraction (), direct fraction (), Perez's clear sky index (ɛ), brightness index (), cloud cover (), air temperature (), pressure (), solar azimuth cosine (), and horizontal global irradiation (). The experimental data are clustered according to the sky conditions, following the CIE standard sky classification. A previous feature selection procedure established the most adequate MIs for modelling in clear, partial and overcast sky conditions. was the common MI used by all models and for all sky conditions. Additional variables were also included: the geometrical parameter, , and three variables related to the sky conditions, , and Both modelling methods, multilinear regression and ANN, yielded very high determination coefficients () with very close results in the models for each of the different sky conditions. Slight improvements can be observed in the ANN models. The results underline the equivalence of multilinear regression models and ANN models of PAR following previous feature selection procedures.Regional Government of Castilla y León, under projects BU021G19 and INVESTUN/19/BU/0004 and the Spanish Ministry of Science & Innovation under the I+D +i state program “Challenges Research Projects” (Ref. RTI2018-098900-B-I00). Diego Granados López expresses his thanks to the Junta de Castilla y León for economic support (PIRTU Program, ORDEN EDU/556/2019)
Pixel-Based Image Processing for CIE Standard Sky Classification through ANN
Digital sky images are studied for the definition of sky conditions in accordance with the CIE Standard General Sky Guide. Likewise, adequate image-processing methods are analyzed that highlight key image information, prior to the application of Artificial Neural Network classification algorithms. Twenty-two image-processing methods are reviewed and applied to a broad and unbiased dataset of 1500 sky images recorded in Burgos, Spain, over an extensive experimental campaign. The dataset comprises one hundred images of each CIE standard sky type, previously classified from simultaneous sky scanner data. Color spaces, spectral features, and texture filters image-processing methods are applied. While the use of the traditional RGB color space for image-processing yielded good results (ANN accuracy equal to 86.6%), other color spaces, such as Hue Saturation Value (HSV), which may be more appropriate, increased the accuracy of their global classifications. The use of either the green or the blue monochromatic channels improved sky classification, both for the fifteen CIE standard sky types and for simpler classification into clear, partial, and overcast conditions. The main conclusion was that specific image-processing methods could improve ANN-algorithm accuracy, depending on the image information required for the classification problem.Regional Government of Castilla y León under the “Support Program for Recognized Research Groups of Public Universities of Castilla y León” (BU021G19) and the Spanish Ministry 595 of Science and Innovation under the I + D + i state program “Challenges Research Projects” (Ref. RTI2018-098900-B-I00). Diego Granados López expresses his thanks for economic support from the Junta de Castilla-León (PIRTU Program, ORDEN EDU/556/2019)
Modificación estética de sonrisa utilizando coronas pediátricas NuSmile.
La sonrisa de un niño es importante para su desarrollo psicológico y funcional. Éstos se preocupan por no enseñar metal en su sonrisa. La AAPD define CIT como la presencia de uno o más dientes cariados, ausentes, o restaurados en dentición primaria, en edad preescolar.Los incisivos primarios superiores son los más afectados con CIT. Hace algunos años se resolvían con extracciones o mediante el uso de coronas acero-cromo.En la última década, se ha despertado en los padres una preocupación estética con relación a dentición primaria, condicionado el que se busquen y generen nuevas alternativas de tratamiento
Informed choice in breast cancer screening: the role of education
[spa ] Objetivo: Evaluar el efecto de recibir información sobre los beneficios y los efectos adversos del cribado del cáncer de mama en la elección informada, en función del nivel educativo. Método: Análisis secundario de un estudio experimental aleatorizado y controlado, en cuatro programas de cribado en Cataluña˜ y Canarias. Se analizaron 400 mujeres que iban a ser invitadas a participar por primera vez. El grupo de intervención recibió una herramienta informativa que mostraba los beneficios y los efectos adversos del cribado. El grupo control recibió un folleto estándar que recomendaba participar en el cribado. El nivel de estudios se agrupó en dos categorías: bajo y alto. La variable principal fue la elección informada definida como un conocimiento adecuado y la concordancia entre las actitudes y las intenciones. Resultados: La intervención produjo un mayor aumento del conocimiento en las mujeres con nivel educativo alto respecto a las de menor nivel educativo. Entre las mujeres que recibieron la intervención, la elección informada fue casi tres veces superior en las de nivel educativo alto (27% vs. 11%). No se observaron diferencias entre niveles educativos en los grupos de intervención y control en cuanto a conflicto decisional, confianza en la decisión, ansiedad y preocupación por el cáncer de mama. Conclusiones: Una herramienta informativa para el cribado del cáncer de mama tuvo mucho más impacto sobre la elección informada en las mujeres con nivel educativo alto. En aquellas con nivel educativo bajo mejoró la actitud frente al cribado y produjo un aumento en la intención de participar en él. [eng] Conclusions: A decision aid for breast cancer screening had much more impact on informed choice among women with a high educational level. In women with low educational level, the attitude towards screening improved and there was an increase in the intention to be screened. Objective: To evaluate the effect of receiving information about the benefits and harms of breast cancer screening in informed choice, according to educational level.
Method: Secondary analysis of a randomized, controlled study, in four screening programs, in Catalonia and the Canary Islands (Spain). We analyzed 400 women who were going to be invited to participate for the first time. The intervention group received a decision aid that showed the benefits and harms of screening. The control group received a standard brochure that recommended participating in the screening program. Educational level was grouped into two categories, low and high. The primary out- come was informed choice defined as adequate knowledge and consistency between attitudes and intentions.
Results: The intervention produced a greater increase in knowledge in women with a high educational level compared to those with a lower educational level. Among women who received the intervention, informed choice was almost three times higher in those with a high educational level (27% versus 11%). No differences were observed between educational levels in decisional conflict, confidence in the decision, anxiety and worry about breast cancer, in the intervention and control groups
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