1,103 research outputs found

    Maintenance of heat and water balances as a scale-up criterion for the production of ethanol by Schwanniomyces castellii in a solid state fermentation system

    Get PDF
    The scale-up of column fermenters by 6 to 410 gravimetric scale factors, from 10 g moist substrate size, has been achieved efficiently by maintaining heat and water balances in the media. The data on the patterns of ethanol production, biomass formation, the concentration of different carbohydrates, dry matter and pH values against time were of equal magnitude in 10- and 60-g size column fermenters. The reactors of 60-, 370- and 4100-g sizes also compared well in respect of O2 consumption, CO2 evolution and the specific growth rates in aerobic and anaerobic fermentations phases. The overall productivities of ethanol were similar in all the four column fermenters. The ability to obtain the same results in all the fermenter sizes, in spite of the increases in the diameter and the height of the columns, indicates the high potential of this simple scale-up criterion which has not been used earlier for scale-up of any fermentation process. (Résumé d'auteur

    Nested shallow geothermal systems

    Get PDF
    The long-term sustainability of shallow geothermal systems in dense urbanized areas can be potentially compromised by the existence of thermal interfaces. Thermal interferences between systems have to be avoided to prevent the loss of system performance. Nevertheless, in this work we provide evidence of a positive feedback from thermal interferences in certain controlled situations. Two real groundwater heat pump systems were investigated using real exploitation data sets to estimate the thermal energy demand bias and, by extrapolation, to assess the nature of thermal interferences between the systems. To do that, thermal interferences were modelled by means of a calibrated and validated 3D city-scale numerical model reproducing groundwater flow and heat transport. Results obtained showed a 39% (522 MWh·yr-1) energy imbalance towards cooling for one of the systems, which generated a hot thermal plume towards the downgradient and second system investigated. The nested system in the hot thermal plume only used groundwater for heating, thus establishing a positive symbiotic relationship between them. Considering the energy balance of both systems together, a reduced 9% imbalance was found, hence ensuring the long-term sustainability and renewability of the shallow geothermal resource exploited. The nested geothermal systems described illustrate the possibilities of a new management strategy in shallow geothermal energy governance

    Funciones Ejecutivas en Estudiantes con Trastorno Específico del Lenguaje al Comienzo de la Escolarización Básica

    Get PDF
    Las funciones ejecutivas (FE) constituyen un conjunto de habilidades implicadas en el control y regulación del funcionamiento cognitivo. La relación entre FE y desarrollo del lenguaje es especialmente relevante en la conceptualización de los trastornos lingüísticos. El objetivo del estudio consistía en explorar el uso diferencial de FE en dos grupos: Desarrollo Lingüístico Típico (DLT) y Trastorno Específico del Lenguaje (TEL). Participaron 44 estudiantes (56,82% niños), 22 DLT y 22 TEL, con edades entre 6,00–6,92 años (M=6.17, DT=.19). El factor diagnóstico previo mostró efectos significativos en atención ejecutiva (p<.001, η2 parcial =.77), memoria de trabajo (p<.001, η2 parcial =.67), flexibilidad cognitiva (p<.01, η2 parcial =.15), y planificación (p<.001, η2 parcial =.63). En todos los casos, salvo en flexibilidad cognitiva, el tamaño del efecto fue fuerte. Los resultados avalarían la tesis de no especificidad en TEL y la posible presencia de disfunciones cognitivas generales que subyacen al trastorno. The executive functions (ef) constitute a set of skills involved in the control and regulation of cognitive functioning. The relation between ef and the development of language is especially relevant regarding the conceptualization of linguistic disorders. This study aims to explore the differential use of ef between two groups: Typical Language Development (tld) and Specific Language Impairment (sli). The participants were 44 students (56, 82% boys), 22 tld and 22 sli, with ages between 6, 00-6, 92 years (m=6.17, sd=.19). The previous diagnostic factor showed significant effects in executive attention (p<.001, ¿2 partial =.77), working memory (p<.001, ¿2 partial =.67), cognitive flexibility (p<.01, ¿2 partial =.15), and planning (p< .001, ¿2 partial =.63). In every case, except for cognitive flexibility, the effect was strong. The results would support the thesis of non-specificity in the sli and the possible presence of general cognitive dysfunctions that underlie the disorder

    Periodontal treatment on patients with cardiovascular disease : systematic review and meta-analysis

    Get PDF
    Atherosclerotic cardiovascular disease is the main cause of mortality in developed countries. It is a chronic and systemic inflammatory disease with a multifactorial etiology. Periodontal disease is one of the many factors that contribute to its development. To analyze the effects of periodontal treatment on cardiovascular risk parameters in patients with atherosclerotic cardiovascular disease. A systematic research was conducted in the Pubmed/Medline databases for clinical trials published up to and including the year 2017. Ten articles were included for analysis. Periodontal treatment reduced C-reactive protein levels (77.8% of clinical trials), tumor necrosis factor-alpha (66.7%), interleukin-6 (100%) and leukocytes (50%). Fibrinogen levels also improved considerably (66.7%). Effects on lipid parameters were more limited, whereby only oxidized low density lipoprotein and very low density lipoprotein cholesterol decreased significantly. Meta-analysis showed a statistically significant decreased in C-reactive protein and leukocytes values when patients were submitted to non-surgical periodontal treatment in contrast to receiving no treatment at all (mean difference 1.199 mg/L, 95% confidence interval: 1.100-1.299, p<0.001; and mean difference 0,79 g/L, 95% confidence interval: 0.717-0.879, p<0.001, respectively). Periodontal treatment has a beneficial effect on some of the biochemical parameters considered to represent cardiovascular risk. Further randomized clinical trials are necessary, with longer follow-up periods including regular periodic monitoring, in order to determine the extent of the impact of periodontal treatment

    Evaluation of the efficiency of a conventional PCR protocol for the diagnosis of bacterial spot disease caused by Xanthomonas arboricola pv. pruni in stone fruits and almond

    Get PDF
    Xanthomonas arboricola pv. pruni (Xap), the causal agent of bacterial spot disease of stone fruits and almond, has a quarantine status for the European Union and the European and Mediterranean Plant Protection Organization. The symptoms in the diverse hosts show some differences and, although being quite typical, could be confused with those of some fungal diseases or other biotic or abiotic causes. Consequently, an accurate molecular diagnosis method is required for a rapid identification of the pathogen in samples of imported plants, from nurseries, orchards, etc. A protocol for conventional PCR designed by Pagani (2004) has been the only molecular analytic tool available for several years. It has been optimised for improving its specificity and sensitivity, and the results of its evaluation in 316 bacterial spot-like symptomatic samples of almond, apricot, cherry, Japanese plum and peach, compared with those of isolation and real-time PCR, are reported. The optimised PCR protocol showed specificity for a collection of Xap strains tested. Few non-desired reactions were obtained with some other xanthomonads which have not been reported from Prunus species. Sensitivity thresholds ranged from 102 to 105 CFU ml-1, depending on the hosts and type of plant material. This conventional PCR assay proved to be an excellent candidate for a rapid screening and presumptive diagnosis in cases where real-time PCR equipment is not available

    Dirac gaugino as leptophilic dark matter

    Full text link
    We investigate the leptophilic properties of Dirac gauginos in an R--symmetric N=2 supersymmetric model with extended gauge and Higgs sectors. The annihilation of Dirac gauginos to leptons requires no chirality flip in the final states so that it is not suppressed as in the Majorana case. This implies that it can be sizable enough to explain the positron excess observed by the PAMELA experiment with moderate or no boost factors. When squark masses are heavy, the annihilation of Dirac gauginos to hadrons is controlled by their Higgsino fraction and is driven by the hZhZ and W+WW^+W^- final states. Moreover, at variance with the Majorana case, Dirac gauginos with a non-vanishing higgsino fraction can also have a vector coupling with the ZZ gauge boson leading to a sizable spin--independent scattering cross section off nuclei. Saturating the current antiproton limit, we show that Dirac gauginos can leave a signal in direct detection experiments at the level of the sensitivity of dark matter searches at present and in the near future.Comment: 24 pages, 10 figures, typos corrected, final version published on JCA

    Meditation experts try Virtual Reality Mindfulness: a pilot study evaluation of the feasibility and acceptability of Virtual Reality to facilitate mindfulness practice in people attending a Mindfulness conference

    Get PDF
    Regular mindfulness practice benefits people both mentally and physically, but many populations who could benefit do not practice mindfulness. Virtual Reality (VR) is a new technology that helps capture participants’ attention and gives users the illusion of “being there” in the 3D computer generated environment, facilitating sense of presence. By limiting distractions from the real world, increasing sense of presence and giving people an interesting place to go to practice mindfulness, Virtual Reality may facilitate mindfulness practice. Traditional Dialectical Behavioral Therapy (DBT®) mindfulness skills training was specifically designed for clinical treatment of people who have trouble focusing attention, however severe patients often show difficulties or lack of motivation to practice mindfulness during the training. The present pilot study explored whether a sample of mindfulness experts would find useful and recommend a new VR Dialectical Behavioral Therapy (DBT®) mindfulness skills training technique and whether they would show any benefit. Forty four participants attending a mindfulness conference put on an Oculus Rift DK2 Virtual Reality helmet and floated down a calm 3D computer generated virtual river while listening to digitized DBT® mindfulness skills training instructions. On subjective questionnaires completed by the participants before and after the VR DBT® mindfulness skills training session, participants reported increases/improvements in state of mindfulness, and reductions in negative emotional states. After VR, participants reported significantly less sadness, anger, and anxiety, and reported being significantly more relaxed. Participants reported a moderate to strong illusion of going inside the 3D computer generated world (i.e., moderate to high “presence” in VR) and showed high acceptance of VR as a technique to practice mindfulness. These results show encouraging preliminary evidence of the feasibility and acceptability of using VR to practice mindfulness based on clinical expert feedback. VR is a technology with potential to increase computerized dissemination of DBT® skills training modules. Future research is warranted

    Cryptosporidium Spp. And Giardia Spp. In Feces And Water And The Associated Exposure Factors On Dairy Farms

    Get PDF
    The aims of this study were to verify the prevalence of Cryptosporidium spp. and Giardia spp. in animal feces and drinking water on dairy farms and to identify a possible relation between the exposure factors and the presence of these parasites. Fecal samples from cattle and humans and water samples were collected on dairy farms in Paraná, Brazil. Analysis of (oo)cysts in the feces was performed by the modified Ziehl-Neelsen staining and centrifugal flotation in zinc sulfate. Test-positive samples were subjected to nested PCR amplification of the 18SSU ribosomal RNA gene for identification of Cryptosporidium and Giardia and of the gp60 gene for subtyping of Cryptosporidium. Microbiological analysis of water was carried out by the multiple-tube method and by means of a chromogenic substrate, and parasitological analysis was performed on 31 samples by direct immunofluorescence and nested PCR of the genes mentioned above. Identification of the species of Cryptosporidium was performed by sequencing and PCR with analysis of restriction fragment length polymorphisms. The prevalence of Giardia and Cryptosporidium was higher in calves than in adults. Among the samples of cattle feces, Cryptosporidium parvum was identified in 41 (64%), C. ryanae in eight (12.5%), C. bovis in four (6.3%), C. andersoni in five (7.8%), and a mixed infection in 20 samples (31.3%). These parasites were not identified in the samples of human feces. Thermotolerant coliform bacteria were identified in 25 samples of water (45.5%). Giardia duodenalis and C. parvum were identified in three water samples. The gp60 gene analysis of C. parvum isolates revealed the presence of two strains (IIaA20G1R1 and IIaA17G2R2) in the fecal samples and one (IIaA17G2R1) in the water samples. The presence of coliforms was associated with the water source, structure and degradation of springs, rain, and turbidity. The prevalence of protozoa was higher in calves up to six months of age. C. parvum and G. duodenalis were identified in the water of dairy farms, as were thermotolerant coliforms; these findings point to the need for guidance on handling of animals, preservation of water sources, and water treatment. © 2017 Toledo et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.12
    corecore