Calibration of a parsimonious distributed ecohydrological daily model in a data-scarce basin by exclusively using the spatio-temporal variation of NDVI

[EN] Ecohydrological modeling studies in developing countries, such as sub-Saharan Africa, often face the problem of extensive parametrical requirements and limited available data. Satellite remote sensing data may be able to fill this gap, but require novel methodologies to exploit their spatiotemporal information that could potentially be incorporated into model calibration and validation frameworks. The present study tackles this problem by suggesting an automatic calibration procedure, based on the empirical orthogonal function, for distributed ecohydrological daily models. The procedure is tested with the support of remote sensing data in a data-scarce environment-the upper Ewaso Ngiro river basin in Kenya. In the present application, the TETIS-VEG model is calibrated using only NDVI (Normalized Difference Vegetation Index) data derived from MODIS. The results demonstrate that (1) satellite data of vegetation dynamics can be used to calibrate and validate ecohydrological models in water-controlled and datascarce regions, (2) the model calibrated using only satellite data is able to reproduce both the spatio-temporal vegetation dynamics and the observed discharge at the outlet and (3) the proposed automatic calibration methodology works satisfactorily and it allows for a straightforward incorporation of spatio-temporal data into the calibration and validation framework of a model.The research leading to these results has received funding from the Spanish Ministry of Economy and Competitiveness and FEDER funds, through the research projects ECOTETIS (CGL2011-28776-C02-014) and TETISMED (CGL2014-58127-C3-3-R). The collaboration between Universitat Politecnica de Valencia, Universita degli studi della Basilicata and Princeton University was funded by the Spanish Ministry of Economy and Competitiveness through the EEBB-I-15-10262 fellowship.Ruiz Perez, G.; Koch, J.; Manfreda, S.; Caylor, KK.; Francés, F. (2017). Calibration of a parsimonious distributed ecohydrological daily model in a data-scarce basin by exclusively using the spatio-temporal variation of NDVI. HYDROLOGY AND EARTH SYSTEM SCIENCES. 21(12):6235-6251. https://doi.org/10.5194/hess-21-6235-2017S623562512112Allen, R. G., Pruitt, W. O., Wright, J. L., Howell, T. A., Ventura, F., Snyder, R., Itenfisu, D., Steduto, P., Berengena, J., Yrisarry, J. B., Smith, M., Pereira, L. S., Raes, D., Perrier, A., Alves, I., Walter, I., Elliott, R.: A recommendation on standardized surface resistance for hourly calculation of reference ET0 by the FAO56 Penman-Monteith method, Agr. 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Swinging Atwood's Machine: Experimental and Theoretical Studies

A Swinging Atwood Machine (SAM) is built and some experimental results concerning its dynamic behaviour are presented. Experiments clearly show that pulleys play a role in the motion of the pendulum, since they can rotate and have non-negligible radii and masses. Equations of motion must therefore take into account the inertial momentum of the pulleys, as well as the winding of the rope around them. Their influence is compared to previous studies. A preliminary discussion of the role of dissipation is included. The theoretical behaviour of the system with pulleys is illustrated numerically, and the relevance of different parameters is highlighted. Finally, the integrability of the dynamic system is studied, the main result being that the Machine with pulleys is non-integrable. The status of the results on integrability of the pulley-less Machine is also recalled.Comment: 37 page

Universal prototype for adapting from conventional centrifugal fertilizer to variable-rate spreader

Congreso Agroingeniería 2015. Orihuela (Alicante). 1 a 3 de junio de 2015La Agricultura de Precisión constituye un nuevo paradigma en la agricultura de hoy. A objetivos como el aumento de la productividad o de la eficiencia económica, se les unen otros en auge como el respeto medioambiental y un riguroso control en la seguridad alimentaria. En general las técnicas de agricultura de precisión requieren de un mejor conocimiento de las necesidades del cultivo y del suelo, y también del empleo de la maquinaria más adecuada que tenga en cuenta la variabilidad espacial y temporal en las necesidades de los cultivos. En este contexto, este estudio tiene como objetivo principal, el diseño, desarrollo y evaluación de una plataforma universal para controlar una abonadora centrífuga convencional mediante un monitor comercial inicialmente diseñado para el control de barras de pulverización de productos líquidos, lo que permite la adaptación dinámica de la cantidad de fertilizante sólido según las necesidades reales del cultivo. Para el desarrollo del sistema de control fue necesario realizar una caracterización de la abonadora mediante pruebas de calibración del sistema dosificador. También se han desarrollado los distintos módulos de hardware (módulo para el control de los discos, interacción con el sistema de control de líquidos comercial, etc.) necesarios para automatizar las acciones que se realizan durante el funcionamiento de la máquina. Para la gestión del sistema se utiliza la plataforma de hardware libre de bajo coste Arduino que resulta fácilmente adaptable para otras abonadoras, desarrollando un software capaz de gestionar el resto de componentes. Finalmente se monta todo el conjunto a bordo del tractor y se realizan las pruebas de funcionamiento. Se comprobó que el sistema trabaja correctamente, con una respuesta adecuada, consiguiendo automatizar el proceso de variar la dosis durante la marcha de forma eficaz.Como se observa en estos primeros resultados, la utilización de este equipo como elemento importante en una aplicación variable de insumos, puede suponer una reducción económica y del impacto medioambiental de la operación, además de permitir una distribución mas racional del nitrógeno u otros fertilizantes en campo, algo sin duda de especial relevancia en sistemas modernos de producción.Precision Agriculture represents a new paradigm in modern agriculture. To objective such as increasing productivity and economic efficiency, are joined other arising objective as the environmental concern. Precision agriculture techniques require a better understanding of crop and soil needs, and the use of precise machinery that take into account the spatial-temporal variability across fields. In these terms, the goal of this study was the design, development and evaluation of a universal platform to control a conventional disc fertilizer spreader, and thus able to manage the amount of fertilizer on the go. A specific on-field calibration was necessary to determine the spreader settings for a given type of fertilizer. The components of the hardware modules (control system of disks, interaction with sections control system, etc.) capable of automating actions performed in operation of the spreader were developed. The control system was developed based on an open-source and low-cost microcontroller-board (Arduino), which could be adapted easily to other spreader model, and a firmware capable to control the hardware components. Once installed on-board, field tests were provided to investigate the proper functioning and response time (approx. 1 sec) of the control system and achieve automate the process of varying the fertilizer dose on the go. As noted these preliminary results, the utilization of this prototype as an essential part of a variable input application may found an economic reduction in fertilizer operation and environmental impact, and allows the control of nitrogen or other fertilizer in fields, techniques that definitely significant in modern agriculture production systems

Temporal analysis of natural radionuclides deposition at Málaga(2005-2016)

Atmospheric deposition of radionuclides has been investigated in many studies from the aspects of both radiation protection and geochemistry. The present study, carried out in the city of Málaga, in the southeast of Spain, focuses on the assessment of the bulk depositional fluxes of three natural radionuclides: 7Be (cosmogenic origin), and 210Pb and 40K (crustal origin). These three radionuclides are useful markers of particles arising from their respective sources. To obtain fundamental information of atmospheric transportation, sedimentation and geological process of particulate matter, a long-term monitoring of atmospheric deposition has been carried out in Málaga from January 2005-December 2016. Samples of bulk deposition were collected on a monthly basis on a stainless steel tray from January 2005 to December 2016. Afterwards, a volume of 6 L of the bulk deposition was reduced via evaporation to 1 L approximately and transferred to a Marinelli geometry container for gamma counting. Additionally, aerosols samples were collected weekly in cellulose membrane filters of 0.8μm pore size and 47mm diameter with an air sampler lodged in an all-weather sampling station, situated on the roof near the bulk rain collector. Gamma counting of the aerosols and bulk deposition samples was performed using an intrinsic germanium coaxial detector, Re-Ge-type (CANBERRA). This study describes the results and then discusses characteristics of atmospheric deposition of mentioned radionuclides with respect to seasonal variations and dependency on controlling factors. The depositional fluxes of all radionuclides showed a clear seasonal trend with summer minimum and high values in wintertime

Dexamethasone-doped nanoparticles improve mineralization, crystallinity and collagen structure of human dentin

zation. This study aims to evaluate bonding ability and both mechanical and chemical behavior of demineralized dentin infiltrated with polymeric nanoparticles doped with dexamethasone (Dex-NPs). Methods: Dentin conditioned surfaces were infiltrated with NPs, Dex-NPs or Dex-Zn-NPs. Bonded interfaces were also created and stored for 24 h or 21d, and then submitted to microtensile bond strength testing. Dentin remineralization was analyzed by Nanohardness, Young’s modulus and Raman analysis. Results: At 21d of storage, dentin treated with undoped-NPs attained the lowest nanohardness and Young’s modulus. Dex-NPs and Zn-Dex-NPs increased dentin nanohardness and Young’s modulus after 21d Raman analysis showed high remineralization, crystallinity, crosslinking and better structure of collagen when functionalized Dex-NPs were present at the dentin interface. Conclusions: Infiltration of dentin with Dex-NPs promoted functional remineralization as proved by nanomechanical and morpho-chemical evaluation tests. Dexamethasone in dentin facilitated crystallographic maturity, crystallinity and improved maturity and secondary structure of dentin collagen. Clinical significance: Using dexamethasone-functionalized NPs before resin infiltration is a clear option to obtain dentin remineralization, as these NPs produce the reinforcement of the dentin structure, which will lead to the improvement of the longevity of resin restorationsGrant PID2020-114694RB-I00 funded by MCIN/AEI 10.13039/501100011033Funding for open access charge: Universidad de Granada / CBUA

Ultra-structure characterization of self-etching treated cementum surfaces

Objectives: to evaluate the effect of different conditioning treatments on surface roughness and topography of dental cementum. Study Design: Extracted human canines were used for the present study. The mesial surface from the cervical third of the roots were ground flat with wet 600-grit silicon carbide paper. They were polished (up to 1/4 µm diamond paste) and treated as follows: 1) No treatment, 2) 35% H3PO4 during 15 s, 3) Clearfil SE Bond primer (SEB), 4) One-Up Bond F (OUB). The adhesive systems were applied following manufacturer?s instructions. SEB primer and OUB were removed from surfaces by washing and ultrasonic agitation with ascending ethanol solutions. Digital images of treated surfaces (5x5 and 15x15 µm) were obtained by means of an atomic force microscope (AFM) analysis. The average surface roughness (Ra nanometers) of the scanned areas was assessed. Data were analyzed by ANOVA and SNK multiple comparisons tests (p<0.05). Results: phosphoric acid treatment produced the highest mean roughness value, at all scan sizes. At 5x5 µm AFM images, for self-etch adhesive systems no differences in roughness were detected. At 15x15 µm, when One-Up Bond F was employed the lowest value was obtained. Conclusions: When phosphoric acid treatment was applied, cementum surface roughness increased and a strong demineralization with exposed collagen fibers could be observed

Anticoncepción poscoital. Características de la demanda

ObjetivoConocer el perfil de las mujeres que demandan anticoncepción poscoital (APC).DiseñoDescriptivo transversal. Emplazamiento. Centro de Orientación Familiar (COF), Área 4 del Instituto Madrileño de Salud. Madrid.ParticipantesTodas las mujeres que acudieron en el año 2000 para requerir APC (n = 404).MedicionesSe realizó una encuesta con variables sociodemográficas relacionadas con la APC y con la vida sexual.ResultadosLa edad media fue de 23,9 años (límites, 14–49); el 9,9% era menor de edad. La media de coitos al mes era de 6,7, el número de años de relaciones sexuales era de 4,9 y el primer coito se produjo, de media, a los 18 años. El 90,9% afirmaba tener pareja estable. Tenía estudios secundarios o universitarios un 75%. El 55,7% manifestaba no haber recibido información sobre anticonceptivos. El 19,5% utilizó APC en otra ocasión. El 6,5% había tenido alguna interrupción voluntaria de embarazo y de éstas, el 36% había utilizado APC anteriormente. Los motivos de consulta fueron: rotura de preservativo (69,3%), preservativo retenido (16,9%) y coito sin protección (12%). El 7% tuvo otros coitos de riesgo en el mismo ciclo. Un 33,2% las remitía su equipo de atención primaria, acudió por conocidos el 19% y desde servicios de urgencias el 16%. Conocía el COF un 26,1%. En el 12,2% no se prescribió APC por mínimo riesgo de embarazo. Realizaron la valoración una enfermera (52,6%), médicos residentes (34,4%) y una ginecóloga (13%).ConclusionesFalta información sobre métodos anticonceptivos. La mayoría de las pacientes son derivadas por otros servicios sanitarios.ObjectiveDefine the profile of the women that ask for emergency contraception (EC).DesignTransversal descriptive investigation.SettingFamiliar Planning Center of 4th Area of Instituto Madrileño de Salud. in Madrid. Participants. All the women that went in the year 2000 requiring EC (n=404).MeasurementsWas carried out a survey with sociodemographic variables, related with the EC and with the sexual life.ResultsThe average age was of 23.9 years (age range 14 to 49) were inquired, 9.9 were under 18. They had an average of 6.7 intercourses per month, the first intercourse when they were 18 years old on average, and 4.9 years of sexual relationships. 90.9% stated to have a couple. 75% were graduated from high school or university, and 55.7% said they had never received information about contraceptives. For 19.5% this was not the first time they asked for EC. 6.5% had interrupted on purpose pregnancy and 36% of them had used EC before. The reasons to demand EC were: condom break (69.3%), held condom (16.9%) and intercourse without any protection (12%). 7% acknowledged other risky intercourses during the same period. 33.2% had been sent by a General Practitioner, 26.1% knew the center, 19% were sent by acquaintances and 16% from Emergency Services. EC was not prescribed in 12.2% of the cases because of minimum risk to pregnancy. The evaluation was made by a nurse (52.6%), by a doctor (34.4%) and by a gynecologist (13%).ConclusionsThere is a lack of information about contraceptive methods. Most of the patients are sent from other sanitary services

Wetting ability of an acetone/based etch rinse adhesive after NaOCl-treatment

Objectives: to evaluate the effect of sodium hypochlorite (NaOCl) treatment on surface dentin roughness (Ra) and contact angle (CA) when using Prime and Bond NT adhesive (PB NT). Study Design: Extracted human third molars were sectioned to expose flat, superficial and deep dentin surfaces. CA and Ra were measured (1) before and (2) after 35% H 3 PO 4 etching, and (3) H 3 PO 4 etching + 5% NaOCl treated for 2 minutes before the application of PB NT. CA was measured by the Axisymmetric Drop Shape Analysis Technique using distilled and deionized water and PB NT. Roughness was evaluated with a profilometer, twelve radial measurements were performed in each treatment surface. Data were analyzed with two-way ANOVA and Newman-Keuls multiple comparison test procedures. Results: CA values decreased after acid etching and even more after NaOCl treatment on deep dentin when water was tested. With resin, there were not differences on CA results after H 3 PO 4 neither after NaOCl treatment, in both dentin surfaces. Etching and NaOCl treatment resulted in surface roughness increase. Conclusions: In spite of the higher roughness after NaOCl treatment on superficial and deep dentin, the use of 5% NaOCl for 2 min after dentin demineralization when PB NT was employed did not improved the wettability of dentin, probably due to nanofiller content and/or hydrogen-bonding interactions with residues of the organic matrix on collagen-depleted denti