358 research outputs found

    Stand-alone lumbar cage subsidence: A biomechanical sensitivity study of cage design and placement.

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    Background and objective: Spinal degeneration and instability are commonly treated with interbody fusion cages either alone or supplemented with posterior instrumentation with the aim to immobilise the segment and restore intervertebral height. The purpose of this work is to establish a tool which may help to understand the effects of intervertebral cage design and placement on the biomechanical response of a patient-specific model to help reducing post-surgical complications such as subsidence and segment instability. Methods: A 3D lumbar functional spinal unit (FSU) finite element model was created and a parametric model of an interbody cage was designed and introduced in the FSU. A Drucker–Prager Cap plasticity formulation was used to predict plastic strains and bone failure in the vertebrae. The effect of varying cage size, cross-sectional area, apparent stiffness and positioning was evaluated under 500 N preload followed by 7.5 Nm multidirectional rotation and the results were compared with the intact model. Results: The most influential cage parameters on the FSU were size, curvature congruence with the endplates and cage placement. Segmental stiffness was higher when increasing the cross-sectional cage area in all loading directions and when the cage was anteriorly placed in all directions but extension. In general, the facet joint forces were reduced by increasing segmental stiffness. However, these forces were higher than in the intact model in most of the cases due to the displacement of the instantaneous centre of rotation. The highest plastic deformations took place at the caudal vertebra under flexion and increased for cages with greater stiffness. Thus, wider cages and a more anteriorly placement would increase the volume of failed bone and, therefore, the risk of subsidence. Conclusions: Cage geometry plays a crucial role in the success of lumbar surgery. General considerations such as larger cages may be applied as a guideline, but parameters such as curvature or cage placement should be determined for each specific patient. This model provides a proof-of-concept of a tool for the preoperative evaluation of lumbar surgical outcomes

    Los aceites minerales pueden ser una alternativa al uso de acaricidas para el control de araña roja

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    Los aceites minerales pueden ser una alternativa muy interesante a los acaricidas para el control de la araña roja, Tetranychus urticae Koch, una plaga que actualmente está produciendo importantes daños en el cultivo de clementinas. Sin embargo, la información sobre la dosificación de estos productos y su eficacia sobre este fitófago es prácticamente inexistente. En este trabajo se evalúa en laboratorio la eficacia de cuatro productos comerciales, a cinco concentraciones diferentes, sobre huevos, protoninfas y adultos de T. urticae. Así mismo, se estudia cómo se depositan estos productos, con el fin de determinar una posible relación entre los parámetros que describen la deposición (recubrimiento, tamaño y densidad de los impactos) y la eficacia acaricida. El producto que produjo mayor área media de las deposiciones fue también el más eficaz para controlar a la araña roja en todos los estadios y con una menor concentración de producto comercial, alcanzando niveles de eficacia de 90-100 %. Los demás aceites consiguieron eficacias elevadas a partir de concentraciones al 1,5 -2,0 %. También se observó que al aumentar la concentración de producto comercial en el caldo, se incrementó el recubrimiento y el área media de los impactos. Los aceites minerales han mostrado un gran potencial para controlar la araña roja en condiciones de laboratorio. El siguiente paso será determinar su eficacia en condiciones de campoMineral oils could be an alternative to acaricides for the control of the red spider mite, Tetranychus urticae, which causes major damage to clementine crops. However, the information on the appropriate dosage of these products and their effectiveness on this pest is practically non-existent. The effectiveness of four commercial mineral oil products (containing 81.49-85% oil) at 5 different concentrations (0.5 -2.0%) was evaluated in a laboratory study using eggs, protonymphs and adults of T. urticae. The study also investigated the deposition of the products to determine whether there was a possible relationship between deposition parameters (coating, size and density) and acaricidal efficacy. The product with the highest average deposition area was also the most effective in mite control at all stages of development, and reached 90-100% efficacy at a low concentration of product. The other 3 oils were also highly efficient at concentrations of 1.5-2%. Increasing concentration of the commercial product increased both coating and average area of impact. Mineral oils have proved to have a huge potential for the control or the red spider mite under laboratory conditions. The next step will be evaluating its efficacy under field conditions

    Listeria monocytogenes Inhibits Serotonin Transporter in Human Intestinal Caco-2 Ce

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    Listeria monocytogenes is a Gram-positive bacterium that can cause a serious infection. Intestinal microorganisms have been demonstrated to contribute to intestinal physiology not only through immunological responses but also by modulating the intestinal serotonergic system. Serotonin (5- HT) is a neuromodulator that is synthesized in the intestinal epithelium and regulates the whole intestinal physiology. The serotonin transporter (SERT), located in enterocytes, controls intestinal 5-HT availability and therefore serotonin’s effects. Infections caused by L. monocytogenes are well described as being due to the invasion of intestinal epithelial cells; however, the effect of L. monocytogenes on the intestinal epithelium remains unknown. The main aim of this work, therefore, was to study the effect of L. monocytogenes on SERT. Caco2/TC7 cell line was used as an enterocyte-like in vitro model, and SERT functional and molecular expression assays were performed. Our results demonstrate that living L. monocytogenes inhibits serotonin uptake by reducing SERT expression at the brush border membrane. However, neither inactivated L. monocytogenes nor soluble metabolites were able to affect SERT. The results also demonstrate that L. monocytogenes yields TLR2 and TLR10 transcriptional changes in intestinal epithelial cells and suggest that TLR10 is potentially involved in the inhibitory effect observed on SERT. Therefore, L. monocytogenes, through TLR10-mediated SERT inhibition, may induce increased intestinal serotonin availability and potentially contributing to intestinal physiological changes and the initiation of the inflammatory response.This work was funded by grants from the Spanish Ministry of Science and Innovation and the European Regional Development Fund (ERDF/FEDER) (BFU2010-18971), Zaragoza University (UZ2014- BIO-03), European Social Found (ESF), and the Aragon Regional Government (B61) and the Foundation for the Study of Inflammatory Bowel Diseases in Aragón (ARAINF 2012/0567). E. Latorre and E. Layunta are PhD student fellows from Aragon Regional Government (B105/11 and B022/13)

    Whole-genome sequencing and genetic analysis reveal novel stress responses to individual constituents of essential oils in Escherichia coli

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    Food preservation by the use of essential oils (EOs) is being extensively studied because of the antimicrobial properties of their individual constituents (ICs). Three resistant mutants (termed CAR, CIT, and LIM) of Escherichia coli MG1655 were selected by subculturing with the ICs carvacrol, citral, and (+)-limonene oxide, respectively. These derivative strains showed increased MIC values of ICs and concomitantly enhanced resistance to various antibiotics (ampicillin, trimethoprim, chloramphenicol, tetracycline, kanamycin, novobiocin, norfloxacin, cephalexin, and nalidixic acid) compared to those for the parental strain (wild type [WT]). Whole-genome sequencing (WGS) of these hyperresistant strains permitted the identification of single nucleotide polymorphisms (SNPs) and deletions in comparison to the WT. In order to analyze the contribution of these mutations to the increased antimicrobial resistance detected in hyperresistant strains, derivative strains were constructed by allelic reversion. A role of the SoxR D137Y missense mutation in CAR was confirmed by growth in the presence of some ICs and antibiotics and by its tolerance to ICs but not to lethal heat treatments. In CIT, increased resistance relied on contributions by several detected SNPs, resulting in a frameshift in MarR and an in-frame GyrB ¿G157 mutation. Finally, both the insertion resulting in an AcrR frameshift and large chromosomal deletions found in LIM were correlated with the hyperresistant phenotype of this strain. The nature of the obtained mutants suggests intriguing links to cellular defense mechanisms previously implicated in antibiotic resistance

    High-accuracy real-time monitoring of solar radiation attenuation in commercial solar towers

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    The main objectives of this work are twofold, the immediate objective is to provide current commercial solar towers with a system able to monitor accurately the solar radiation attenuation, the midterm objective is to acquire, with the adequate and precise measurements, the necessary knowledge about the different phenomena involved in the atmospheric attenuation in order to correlate it with meteorological and weather conditions when possible. The purpose of this paper is to describe the basic design features and operational capabilities of a new system designed by CENER and the University of Zaragoza (patent P201830758) for measuring real-time atmospheric attenuation of solar radiation at surface level. It performs a direct measurement without needing any previous assumption about atmospheric conditions. The work will be complemented with the analysis of the influence of atmospheric aerosols and meteorological conditions at surface level in atmospheric attenuation (at the lower ~300m atmospheric layer)

    Yield and Economic Results of Dif-ferent Mechanical Pruning Strategies on "Navel Foyos" Oranges in the Mediterranean Area

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    [EN] Pruning is one of the most manpower-consuming agricultural operations in citrus production.Mechanical pruning can help to reduce pruning time and costs. In order to obtain the knowledge of its effects on the important orange variety ¿Navel Foyos¿, several pruning strategies that include manual pruning and various intensities of mechanical pruning were tested for three years. The results showed that in ¿Navel Foyos¿ oranges, the mechanical pruning strategies did not affect the yield nor the size of the fruit in comparison with manual pruning. In conclusion, mechanical strategies are a potential alternative to manual pruning because they reduce the time necessary to prune and the pruning costs, thereby maintaining or even increasing the yield.This research was funded by (1) the project "Application of new technologies for a comprehensive strategy of mechanized citrus harvesting (CITRUSREC)" funded by the Spanish National Institute for Agriculture and Food Research and Technology (INIA) and the Ministry of Economy, Industry and Competitiveness of Spain (project RTA2014-00025-C05-00), cofunded by the European Regional Development Fund (ERDF); (2) the project of the Operative Group "Technological advances for modernization and sustainability in citrus production. (GO CITRUSTECH)" cofunded by the Agricultural European of Rural Developing-EAFRD (80%) and the Ministry of Agriculture, Fisheries, and Food (20%); (3) the project "Engineering developments to ensure profitable, sustainable and competitive agriculture from farm to fork" cofinanced by the Valencian Institute of Agricultural Research (IVIA) and by the European Regional Development Fund (ERDF). G.M. was a beneficiary of a scholarship for training and specialization of the European Social Fund (ESF).Chueca, P.; Mateu, G.; Garcerá, C.; Fonte, A.; Ortiz Sánchez, MC.; Torregrosa, A. (2021). Yield and Economic Results of Dif-ferent Mechanical Pruning Strategies on "Navel Foyos" Oranges in the Mediterranean Area. Agriculture. 11(1):1-12. https://doi.org/10.3390/agriculture1101008211211

    Effects of active video games on health-related physical fitness and motor competence in children and adolescents with overweight or obesity: Systematic review and meta-Analysis

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    Background: Childhood obesity is one of the most important public health problems. Active video games (AVGs) have been proposed as an attractive alternative to increase energy expenditure and are being investigated to determine their effectiveness against childhood obesity. Objective: The aim of this study is to summarize the existing research and draw conclusions about the effects of AVGs on health-related physical fitness and motor competence in children and adolescents with overweight and obesity. Methods: The search strategy was applied to PubMed, MEDLINE, Web of Science, and SPORTDiscus, including randomized and nonrandomized controlled trials investigating the effects of AVG programs on health-related physical fitness and motor competence in children and adolescents with overweight and obesity. To measure the risk of bias in randomized and nonrandomized controlled trials, 2 different quality assessment tools were used. In total, 15 articles met the inclusion criteria, and the variables of interest were BMI, body fat percentage, cardiorespiratory fitness (CRF), waist circumference, fat-free mass, muscular fitness, and motor competence. A meta-Analysis was performed. Results: Positive effects were found for BMI and body fat percentage, favoring the AVG group compared with a control group with no intervention (mean difference-0.209; 95% CI-0.388 to-0.031 vs mean difference-0.879; 95% CI-1.138 to-0.602). Positive effects seem to be observed for CRF. The effects of AVG interventions on muscular fitness, fat-free mass, waist circumference, and motor competence are unclear. Conclusions: AVG programs showed positive effects on BMI, body fat percentage, and CRF. AVG could be a good strategy to combat childhood obesity. © 2021. KJMIR Publications Inc.. All right reserved

    Intensification of UV-C tertiary treatment : Disinfection and removal of micropollutants by sulfate radical based Advanced Oxidation Processes

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    This study explores the enhancement of UV-C tertiary treatment by sulfate radical based Advanced Oxidation Processes (SR-AOPs), including photolytic activation of peroxymonosulfate (PMS) and persulfate (PS) and their photocatalytic activation using Fe(II). Their efficiency was assessed both for the inactivation of microorganisms and the removal or micropollutants (MPs) in real wastewater treatment plant effluents. Under the studied experimental range (UV-C dose 5.7-57 J/L; UV-C contact time 3 to 28 s), the photolysis of PMS and PS (0.01 mM) increased up to 25% the bacterial removal regarding to UV-C system. The photolytic activation of PMS led to the total inactivation of bacteria (approximate to 5.70 log) with the highest UV-C dose (57 J/L). However, these conditions were insufficient to remove the MPs, being required oxidant's dosages of 5 mM to remove above 90% of carbamazepine, diclofenac, atenolol and triclosan. The best efficiencies were achieved by the combination of PMS or PS with Fe(II), leading to the total removal of the MPs using a low UV-C dosage (19 J/L), UV-C contact time (9 s) and reagent's dosages (0.5 mM). Finally, high mineralization was reached ( > 50%) with photocatalytic activation of PMS and PS even with low reagent's dosages.Peer reviewe
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