Geometric optimal control of the contrast imaging problem in Nuclear Magnetic Resonance

The objective of this article is to introduce the tools to analyze the contrast imaging problem in Nuclear Magnetic Resonance. Optimal trajectories can be selected among extremal solutions of the Pontryagin Maximum Principle applied to this Mayer type optimal problem. Such trajectories are associated to the question of extremizing the transfer time. Hence the optimal problem is reduced to the analysis of the Hamiltonian dynamics related to singular extremals and their optimality status. This is illustrated by using the examples of cerebrospinal fluid / water and grey / white matter of cerebrum.Comment: 30 pages, 13 figur

Vitamin E levels and lipid oxidation in ω3 fatty acids enriched eggs

With the aim to establish the required amount of α-tocopherol to effectively prevent lipid oxidation in w3 FA enriched eggs, a trial was conducted with 2XX laying hens. Birds were randomly assigned to four treatments resulted from supplying a basal diet containing 5% of linseed oil (diet: 65% PUFA, 34,5% m3) with 0 (C), 50 (50E), 100 (I00E) or 200 (200E) ppm of alpha-tocopherol acetate. After 25 days of feeding, eggs were collected and lipid oxidation was measured by the Induced TBArs methodologya (Kornbrust and Mavis, 19X0) and expressed as ng MDA/g egg. At 150 min of incubation, supplementation with 50, 100, or 200 ppm of Vitamin F. promoted a dramatic decrease in the TBArs values of all treatments when compared to the control group (C: 2,63 v.v. 50E: 0,47; I00E: 0,4X; 200E: 0,3X; P«).00l). Moreover, no significant differences were found according to different levels of Vitamin E supplementation. From these data, we can conclude that supplying hens' diets with 50 ppm of alphatocopherol acetate can effectively reduce the lipid oxidation in co3 FA enriched eggs

Cotilos impactados vs. roscados no cementados: estudio radiológico post-operatorio comparativo

Se han valorado radiografías AP de pelvis obtenidas tras colocación de 102 pró- tesis no cementadas en 97 pacientes: 51 eran del tipo cótilo roscado (CR), y 51 del tipo cótilo impactado (CI). Se ha medido el ángulo de inclinación, la posición del cotilo, el grado de centraje, el grado de protrusión/extrusión, y la superficie de contacto entre cótilo y la cavidad acetabular. Globahnente los CR quedan implantados más verticalmente que los CI (p=0,006), así como más lateralizados (p=0,02). El porcentaje de cótilos bien centrados en relación al acetábulo es mayor entre los CI que entre los CR (p=0,002). Un 19% de los CR quedaron parcialmente extraídos, no llegando a contactar con el fondo de la cavidad acetabular, mientras que en ningún caso de los CI se apreció este problema. En conclusión, a pesar de la teórica ventaja de poseer una estabilidad inicial mayor, la orientación de los CR no resulta tan óptima como la obtenida con los CI, lo que asegura una estabilidad mejor a largo plazo y una menor usura del polietileno.—Post-operative anteroposterior radiographs of the pelvis in 102 patients receiving a cementless total hip arthroplasty were analyzed. In a group, a screwed spherical socket (SCR) was applied, while in other a press-fit impacted socket (IMP) was used. The following parameters were studied: inclination angle, location and centering of the acetabular component, degree of protrusion-extrusion, and porcentage of contact surface between the socket and the acetabulum. SCR sockets appeared to be placed more vertically (p=0.006), and laterally (p=0.02) than IMP prostheses. The percent of properly centered sockets was higher among IMP than among SCR implants (p=0.002). SCR prostheses were found to be partly extruded in 19% of cases while none of the IMP prostheses had this problem. In conclussion, despite the theoretical advantage of the SCR implants having a better initial fixation than the IMP implants, the latter tend to be implanted in a more optimal position, thus ensuring a better longterm stability and therefore less wear problems can be expected

"Ethnic disparities in the prevalence of Molar-Incisor-Hypomineralisation (MIH) and caries among 6-12-year-old children in Catalonia, Spain"

AIM: To study the prevalence of MIH and caries in 6- and 12-year-old schoolchildren and their association with ethnic disparities and other relevant factors. BACKGROUND: In recent years, there has been uneven improvement in school children's oral health, highlighting inequalities in access to dental care and health outcomes, particularly among ethnic minorities. The most prevalent oral disease in childhood, caries, is preventable, as its risk factors are well known. However, MIH, a common condition affecting the enamel of permanent incisors and/or molars, has no established aetiology or preventive measures. METHODS: A cross-sectional study among schoolchildren was conducted in 725 children from Masnou (Barcelona, 2013) and in 577 children from Sant Andreu de Llavaneres (Barcelona, 2018-2020). Data collection was carried out by means of clinical examination and a selfreferenced questionnaire. Oral health outcomes included: presence of dental caries, presence of MIH, hypomineralised second primary molars (HSPM). All variables were analysed according to ethnic disparities and other variables such as socioeconomics, diet, hygiene habits, plaque and access to dental services. We performed multivariate Poisson regression models with robust variance to examine ethnic disparities in MIH and caries. CONCLUSION: This cross-sectional study based in Catalonia, Spain showed that there are ethnic disparities in caries as observed with other child's diseases; however, they do not seem to follow the same pattern for MIH. More studies are needed (i) to explore how MIH behaves among populations in terms of inequality; (ii) to study the aetiological factors of MIH; and (iii) to identify potential factors associated with MIH and caries that have not been studied and that may contribute to the observed ethnic disparities.</p

Aplicabilidad del riego a pulsos en tablares

[ES] Se presentan ocho ensayos comparativos entre riego a pulsos y riego continuo en tablares, para variadas condiciones de parcelas y variables de riego. Se ha analizado el tiempo de aplicación para llegar al final de la parcela, la lámina infiltrada media, el coeficiente de uniformidad, y el perfil de agua infiltrada. Los resultados muestran que en la mayoría de los ensayos el riego continuo ha mejorado el riego a pulsos. Las condiciones en que el riego a pulsos ha resultado mejor son : Caudales unitarios bajos (1.5 l/s/m), aspereza o rugosidad hidráulica baja (n = 0.02) y suelo recién labrado. El factor controlador de la efectividad de los pulsos en riego por tablares parece ser el volumen superficial durante el avance; cuando este es grande, la efectividad disminuye.Monserrat, J.; Casali Sarasibar, J.; Tilló, J.; Cots I Rubió, L.; Barragán, J. (1997). Aplicabilidad del riego a pulsos en tablares. Ingeniería del Agua. 4(2):29-36. https://doi.org/10.4995/ia.1997.2720SWORD293642Allen, N. L. (1980). Advance Rates in Forrow Irrigation for Cycled Flow. Ph.D. diss. Utah State University, Logan.Blair, A.W. (1986) Surge flow irrigation infiltration. In Surge Flow Irrigation Field Guide. U.S.D.A.- S.C.S.Coolidge, P. S. (1981) Advance Rates Under Automated Pulsed Flow Irrigation System. Ph.D. diss. Utah State University, Logan.Camacho, E. (1993) Caracterización, optimización y manejo del riego por surcos mediante pulsaciones intermitentes. Tesis Doctoral. Universidad de Córdoba.Goldhamer, D.A., H.A. Mohammad and R.C. Phene (1987) Surge vs. continous-flow irrigation. California Agriculture, Sep-Oct: 29-32.Izuno, F.T., T.H. Podmore and H.R. Duke, (1985) Infiltration under surge irrigation. Transactions of ASAE 28 (2): 517-521.Monserrat, J., (1994). Solución al problema inverso del riego por tablares mediante un modelo hidrológico mixto. Tesis Doctoral. E.T.S.I.A., Universidad de Lleida.Podmore, T. H. and H. R. Duke, (1982). Field evaluation of Surge Flow Irrigation. Paper 82-2012. A.S.A.E, Madison, Wisconsin.Poole, G. J. (1981). Infiltration and Advance Under Surge Flow Irrigation. Ph.D. diss. Utah State University, Logan.Stringham, G. E.and J. Keller, (1979). Surge Flow Automatic Irrigation. Irrigation and Drainage Divi-sion Speciality Conference, A. S. C. E., Albuquerque, New Mexico.U.S.D.A - S.C.S. (1986). Surge Flow Irrigation Field Guide. 32 pp.Walker, W.R and G. V. Skogerboe, (1987). Surface irrigation: Theory and Practice. Prentice-Hall, INC, Englewood Clifs, New Yersey. 386 ppWestesen, G. L and D. K. Biglen, (1986). Surge flow border irrigation trials. A.S.A.E. paper n°: 86-2082

Acidification and solar drying of manure-based digestate to produce improved fertilizing products

The increase in energy and fertilizer consumption makes it necessary to develop sustainable alternatives for agriculture. Anaerobic digestion and digestates appeared to be suitable options. However, untreated digestates still have high water content and can increase greenhouse gas emissions during storage and land application. In this study, manure-derived digestate and solid fraction of digestate after separation were treated with a novel solar drying technology to reduce their water content, combined with acidification to reduce the gaseous emissions. The acidified digestate and acidified solid fraction of digestate recovered more nitrogen and ammonia nitrogen than their respective non-acidified products (1.5–1.3 times for TN; 14 times for TAN). Ammonia and methane emissions were reduced up to 94% and 72% respectively, compared to the non-acidified ones, while N2O increased more than 3 times. Dried digestate and dried acidified digestate can be labeled as NPK organic fertilizer regarding the European regulation, and the dried solid fraction and the improved dried acidified solid fraction can be labeled as N or P organic fertilizer. Moreover, plant tests showed that N concentrations in fresh lettuce leaves were within the EU limit with all products in all the cases. However, zinc concentration appeared to be a limitation in some of the products as their concentration exceeded the European legal limits.This work was funded by the European Union under the Circular Agronomics project (H2020 research and innovation project Nº.773649) and Nutry2Cycle project (H2020 research and innovation project Nº.773682). IRTA thanks the support of the CERCA Program and the Consolidated Research Group TERRA (ref.2017SGR1292), both from the Generalitat de Catalunya. L. Morey thanks the financial support of AGAUR, of the Generalitat de Catalunya (grant reference number 2019FI_B00694). We would like to thank the help of Celia Segura Godoy and Pau Berenguer i Planas during the sampling campaigns.Peer ReviewedPostprint (published version