133 research outputs found

    REFLEXIONES SOBRE LA CONCEPCIÓN TEÓRICA COMO RESULTADO CIENTÍFICO

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    In this article a review of the term of conception is from scientific research, treated by different authors, from different positions depending on the area of ​​knowledge, which is defined as theoretical, methodological, didactic, educational, theoretical or methodological. Some overlap in the definitions, structure and purpose, which must be realized in practice, so it is understood that the concept is a theoretical basis and is realized through systems, methodologies, strategies  and other practical results were seen.En el presente artículo se realiza una valoración sobre el término de concepción desde la investigación científica, tratado por diferentes autores, desde diferentes posiciones según el área de conocimiento, donde es definida como teórica, metodológica, didáctica, educativa, o teórico-metodológica. Se aprecia cierta coincidencia en las definiciones,  estructura y la finalidad, que debe concretarse en la práctica, por lo que se entiende que la concepción es un sustento teórico y se materializa, mediante sistemas, metodologías, estrategias y otros resultados prácticos

    Seroprevalence of Toxoplasma gondii and associated risk factors in domestic pigs raised from Cuba

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    A cross-sectional study was carried out to determine the seroprevalence of Toxoplasma gondii and associated risk factors in pigs in the largest pork-producing region in Cuba. Serum samples from 420 pigs, including 210 sows and 210 post-weaning pigs, were tested for antibodies against T. gondii using a commercial indirect enzyme-linked immunosorbent assay. Anti-T. gondii antibodies were detected in 56 animals (13.3%, 95% CI: 10.1–16.6). A generalized estimating equations model revealed that the risk factors associated with higher seropositivity in pigs were altitude (higher in farm’s location < 250 m above sea level (masl) versus ≥ 250 masl) and age (higher in sows compared to post-weaning pigs). The results indicated that this protozoan parasite is widely distributed on pig farms in the study area, which is a public health concern since the consumption of raw or undercooked pork meat products containing tissue cysts is considered one of the main routes of T. gondii transmission worldwide. Control measures should be implemented to reduce the risk of exposure to T. gondii in pigs in Cuba

    Integrated Environmental and Exergoeconomic Analysis of Biomass-Derived Maleic Anhydride

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    Life cycle analysis and exergy analysis are applied to compare the production of maleic anhydride from different feedstock, both biomass- and petrochemical-derived raw materials, in order to evaluate the sustainability of alternative biorefinery processes to conventional routes. The considered processes involve two options: gas and aqueous phase furfural oxidation with oxygen (air) and hydrogen peroxide as oxidants, respectively, considered as sustainable technologies because of the use of renewable feedstock. Conventional routes, used as benchmarks, include the current production processes using benzene or butane as raw materials. The results show that the aqueous phase process is far from being viable from an energy and environmental point of view due to the high exergy destruction and the use of H2O7 as oxidant (whose production entails important environmental drawbacks). On the contrary, the gas phase oxidation of furfural shows competitive results with petrochemical technologies. Nevertheless, the major environmental drawback of the new furfural-to-maleic anhydride production processes is detected on the environmental profile of the starting raw material. The results suggest that a better environmental footprint for maleic anhydride production in gas phase can be obtained if environmentally friendly furfural production technologies are used at the commercial scale.This research was funded by the Spanish Ministry of Science, Innovation and Universities (projects RTI2018-094918-B-C41, RTI2018-094918-B-C42, and RTI2018-094918-B-C43)

    Consistencia en los estilos de madres y padres y estrés manifestado en adolescentes

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    Este estudio tenía por objetivo examinar si la atribución individual y conjunta del estilo de socialización familiar se relacionaba con las manifestaciones emocionales, fisiológicas y conductuales asociadas al estrés. Ochocientos cincuenta y siete estudiantes de educación secundaria obligatoria, con edades com prendidas entre los 12 y los 16 años, participaron en este estudio. Para identificar los diferentes estilos educativos parentales se realizaron dos análisis de clusters por separado (madres y padres) empleando las puntuaciones otorgadas en diferentes dimensiones (afecto, disciplina inductiva, disciplina rígida y disciplina negligente). Los resultados sugieren que la atribución de un estilo de socialización familiar democrático se relaciona con menores índices de manifestaciones emocionales, fisiológicas y conductuales vinculadas al estrés. Asimismo, la presencia de un padre democrático en la familia parece asociada a la reducción de manifestaciones de estrés cuando se compara con la combinación de cualquier otro patrón incongruente e incluso congruente distinto al democrático. Finalmente, los chicos afirmaron exhibir en mayor grado que las chicas manifestaciones conductuales asociadas al estrés.This study was conducted with the goal of evaluating whether individual and joined attributions of parenting styles (authoritative, permissive, affective-authoritarian and neglectful) was related to emotional, physiological and behavioral manifestations of stress. Eight hundred and fifty seven high school students of compulsory secondary education ranging 12 and 16 years old participated in the study. To identify parenting styles, two separate cluster analyses were conducted on the maternal and paternal parenting variables (caring, inductive discipline, severe discipline and indulgent discipline). Results suggested that authoritative parenting style was linked to lower levels of physiological, emotional and behavioral manifestations of stress. Moreover, the presence of an authoritative parent is linked to stress reduction when compared with any other congruent or incongruent parenting style different from the authoritative one. Finally, boys showed behavioral manifestations of stress in a higher degree than girls

    Bacterial antigen translocation and age as BMI-independent contributing factors on systemic inflammation in NAFLD patients

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    Background & Aims Low‐grade systemic inflammation is a crucial landmark in NAFLD favouring disease progression and comorbidities. We evaluated the input of circulating bacterial antigens on systemic markers of inflammation in NAFLD patients. Patients & Methods Multicenter cross‐sectional study including consecutive patients with biopsy‐proven NAFLD. Demographic, metabolic and fibrosis‐related variables were collected. Circulating bacterial antigens were quantified in blood. Toll‐like receptor SNPs were genotyped. Serum cytokine levels were evaluated. Peripheral blood mononuclear cell response to bacterial antigens was evaluated in vitro. Results Three hundred and fifteen patients from five Spanish hospitals were distributed by BMI. At least, one bacterial antigenic type was found in 66 patients with BMI 30 (77.3%) (P = .014). HOMA‐IR was significantly higher in the presence of circulating antigens among patients with BMI < 30. NASH and significant fibrosis in non‐obese patients were more frequent in the presence of at least two circulating antigenic types. Allelic frequencies of TLR variants were similar to controls and did not affect clinical or laboratory parameters. Pro‐inflammatory cytokines were significantly increased in patients with bacterial antigens, regardless of BMI. TLR gene and protein expression levels were significantly increased in PBMCs from patients with bacterial antigens. Antigen concentrations independently influenced TNF‐α and IL‐6, in both BMI subgroups of patients. Age independently influenced TNF‐α and IL‐6 in non‐obese patients, and TNF‐α in obese patients. Conclusion Serum circulating bacterial antigens as well as age were BMI‐independent factors related to increased systemic inflammation in NAFLD and provides insight on the multifaceted sources of inflammation in these patients.This work has been funded by grants PI16/0967 and PI17/0535 from Instituto de Salud Carlos III, Madrid, Spain, and PROMETEO 2016/001 from Generalitat Valenciana, Valencia, Spain. IGH was recipient of a Young Investigator Grant by CIBERehd, Instituto de Salud Carlos III, Madrid, Spain

    Hàbitat en cova i espai pels ramats ca.6200-6000 BP:La Cova Colomera (Prepirineu de Lleida) durant el Neolític Antic.

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    En aquest treball es presenten les dades referents a la Cova Colomera (Sant Esteve de la Sarga, Pallars Jussà) durant el Neolític cardial final. A partir de diferents sondejos duts a terme des de l'any 2005, s'ha pogut observar la varietat d'usos i funcionalitats del jaciment en moments potencialment sincrònics. Per una banda,una zona on predominen les estructures de caire domètic (fogars, fosses i forats de pal)que ens mostren les dades entorn a l'hàbitat al jaciment; i per altra banda, un gran sector de la cavitat dedicat a l'estabulació dels ramats amb sediments de tipus fumier i probablement també a l'emmagatzematge. Tot això succeix en unes datacions d'entre 6180 +/- 40 i 6020 +/- 510BP. Aquestes dades es contextualitzen amb les d'altres jaciments de la zona pirinenca, un àmbit que sempre ha estat definit en la bibliografia com un espai de pas entre diferents biòtops ecològics, de les plantes fèrtils a les pastures de l'estiu

    Brown bear behaviour in human-modified landscapes: The case of the endangered Cantabrian population, NW Spain

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    Large carnivores are recolonizing parts of their historical range in Europe, a heavily modified human landscape. This calls for an improvement of our knowledge on how large carnivores manage to coexist with humans, and on the effects that human activity has on large carnivore behaviour, especially in areas where carnivore populations are still endangered. Brown bears Ursus arctos have been shown to be sensitive to the presence of people and their activities. Thus, bear conservation and management should take into account potential behavioural alterations related to living in human-modified landscapes. We studied the behaviour of brown bears in the Cantabrian Mountains, NW Spain, where an endangered population thrives in a human-modified landscape. We analysed bear observations video-recorded over a 10-year period to try to identify human and landscape elements that could influence bear behaviour. Neither the occurrence nor the duration of vigilance behaviour in Cantabrian bears seemed to be influenced by the proximity of human infrastructures and activity. Our findings suggest that the general pattern of human avoidance by bears is adapted to the human-modified landscape they inhabit. Bears generally avoid people, but close presence of human infrastructures or activity did not seem to trigger an increased bear behavioural response. Coexistence between large carnivores and humans in human-modified landscapes is possible, even when human encroachment is high, provided that carnivores are not heavily persecuted and direct interactions are avoided. Further research should also document the potential existence of other responses to human presence and activity, e.g., hunting, traffic noise, and measuring stress levels with physiological indicators.This research was financially supported by the IBA (International Association for Bear Research and Management) grant project IBA-RG_16_2016 ‘Brown bear behaviour in human-dominated landscapes: the effect of human density and ecotourism’. During this research, G.B. was financially supported by a collaboration contract with the MUSE – Museo delle Scienze of Trento (Italy), J.M-P. was supported by the ARAID foundation and V.P., A.O. and R.G.G. were also financially supported by the Excellence Project CGL2017-82782-P financed by the Spanish Ministry of Economy, Industry and Competitiveness (MINECO), the Agencia Estatal de Investigación (AEI) and the Fondo Europeo de Desarrollo Regional (FEDER, EU)

    Do nutritional supplements have a role in age macular degeneration prevention?

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    Purpose. To review the proposed pathogenic mechanisms of age macular degeneration (AMD), as well as the role of antioxidants (AOX) and omega-3 fatty acids (omega-3) supplements in AMD prevention. Materials and Methods. Current knowledge on the cellular/molecular mechanisms of AMD and the epidemiologic/experimental studies on the effects of AOX and omega-3 were addressed all together with the scientific evidence and the personal opinion of professionals involved in the Retina Group of the OFTARED (Spain). Results. High dietary intakes of omega-3 and macular pigments lutein/zeaxanthin are associated with lower risk of prevalence and incidence in AMD. The Age-Related Eye Disease study (AREDS) showed a beneficial effect of high doses of vitamins C, E, beta-carotene, and zinc/copper in reducing the rate of progression to advanced AMD in patients with intermediate AMD or with one-sided late AMD. The AREDS-2 study has shown that lutein and zeaxanthin may substitute beta-carotene because of its potential relationship with increased lung cancer incidence. Conclusion. Research has proved that elder people with poor diets, especially with low AOX and omega-3 micronutrients intake and subsequently having low plasmatic levels, are more prone to developing AMD. Micronutrient supplementation enhances antioxidant defense and healthy eyes and might prevent/retard/modify AMD

    Influence of subclinical endometritis on the reproductive performance of dairy cows

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    The aim of this study was to evaluate the influence of subclinical endometritis (SE) on the reproductive performance of dairy cows. Ninety-four dairy cows of parity 1 to 8, distributed in 25 herds, were examined once between 30 and 45 days in milk using transrectal palpation, vaginoscopy and ultrasonography. A cytological sample of the endometrium was taken only from cows with an apparent healthy uterus (n=65). Serum glucose, total cholesterol, triglycerides, non-esterified fatty acids, β-hydroxybutyrate, total proteins, albumin, urea and hepatic enzymes were analyzed. Reproductive indexes were recorded during the next 11 months. Endometrial cytology was considered indicative of SE if percentage of polymorphonuclear neutrophils was superior to 5% of all cells present in the smear, except erythrocytes. Results indicated that 14.9% of the cows sampled for uterine cytology had SE, and that healthy cows become pregnant significantly before than those with SE (hazard ratio=2.35; 95% confidece interval: 1.05-5.3). From all the metabolic and productive variables analyzed, only triglycerides affected negatively to reproduction; serum albumin concentration, body condition score and milk production had positive effects on the reproductive performance. In conclusion, our results indicate that SE has a negative impact on reproductive performance and uterine cytology is necessary to diagnose it since almost 15% of the affected animals were not detected by other diagnosis methodsXunta de Galicia (Programa Sectorial de Medio Rural, Proyecto Ref. PGIDIT07MRU002E) and FEFRIGA, Santiago de Compostela, SpainS
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