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161.
Marta Rey-López Rebeca P. Díaz-Redondo Ana Fernández-Vilas José J. Pazos-Arias Jorge García-Duque Alberto Gil-Solla Manuel Ramos-Cabrer 《Computer Standards & Interfaces》2009,31(2):309-318
Current e-learning standards have been designed to provide reusability and interoperability. Besides these features, content personalisation is also necessary, although current standards do not fully support it. In this paper, we study the adaptation possibilities of the SCORM standard and present an extension to permit adaptivity according to user's characteristics. It comprises a syntax for adaptivity rules based on a set of adaptation parameters. The actual values of these adaptation parameters are deduced from the user profile, using inference rules. As a result, adaptive courses are obtained, created with the aim of being personalised before shown to the student. 相似文献
162.
Marina Romaní-Prez Clara Bullich-Vilarrubias Inmaculada Lpez-Almela Rebeca Libana-García Marta Olivares Yolanda Sanz 《International journal of molecular sciences》2021,22(11)
Obesity currently represents a major societal and health challenge worldwide. Its prevalence has reached epidemic proportions and trends continue to rise, reflecting the need for more effective preventive measures. Hypothalamic circuits that control energy homeostasis in response to food intake are interesting targets for body-weight management, for example, through interventions that reinforce the gut-to-brain nutrient signalling, whose malfunction contributes to obesity. Gut microbiota–diet interactions might interfere in nutrient sensing and signalling from the gut to the brain, where the information is processed to control energy homeostasis. This gut microbiota–brain crosstalk is mediated by metabolites, mainly short chain fatty acids, secondary bile acids or amino acids-derived metabolites and subcellular bacterial components. These activate gut–endocrine and/or neural-mediated pathways or pass to systemic circulation and then reach the brain. Feeding time and dietary composition are the main drivers of the gut microbiota structure and function. Therefore, aberrant feeding patterns or unhealthy diets might alter gut microbiota–diet interactions and modify nutrient availability and/or microbial ligands transmitting information from the gut to the brain in response to food intake, thus impairing energy homeostasis. Herein, we update the scientific evidence supporting that gut microbiota is a source of novel dietary and non-dietary biological products that may beneficially regulate gut-to-brain communication and, thus, improve metabolic health. Additionally, we evaluate how the feeding time and dietary composition modulate the gut microbiota and, thereby, the intraluminal availability of these biological products with potential effects on energy homeostasis. The review also identifies knowledge gaps and the advances required to clinically apply microbiome-based strategies to improve the gut–brain axis function and, thus, combat obesity. 相似文献
163.
Atkins David C.; Marín Rebeca A.; Lo Tracy T. Y.; Klann Notker; Hahlweg Kurt 《Canadian Metallurgical Quarterly》2010,24(2):212
Infidelity is an often cited problem for couples seeking therapy, but the research literature to date is very limited on couple therapy outcomes when infidelity is a problem. The current study is a secondary analysis of a community-based sample of couple therapy in Germany and Austria. Outcomes for 145 couples who reported infidelity as a problem in their relationship were compared with 385 couples who sought therapy for other reasons. Analyses based on hierarchical linear modeling revealed that infidelity couples were significantly more distressed and reported more depressive symptoms at the start of therapy but continued improving through the end of therapy and to 6 months posttherapy. At the follow-up assessment, infidelity couples were not statistically distinguishable from non-infidelity couples, replicating previous research. Sexual dissatisfaction did not depend on infidelity status. Although there was substantial missing data, sensitivity analyses suggested that the primary findings were not due to missing data. The current findings based on a large community sample replicated previous work from an efficacy trial and show generally optimistic results for couples in which there has been an affair. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
164.
Sánchez Alvarez V Hernández Triana M Abreu Peñate M de las Cagigas Reig A Tam Hurtado M Reboso Pérez J Noa Puig M Arias Verdé J Fernández Carriera R González Calderín S Sigarroa González A 《Archivos latinoamericanos de nutrición》2002,52(1):35-42
The influence of low levels of protein and vitamin A on indicators of the immune response was assayed in rats. The levels of protein and vitamin A intake of the Cuban population affected by epidemic neuropathy in 1993 was reproduced in 4 diets: control, protein deficiency (DP), vitamin A deficiency (DA), protein and vitamin A deficiency (DAP). The Peyer's patches evaluated the Interleukin 1 expression gene and was related with corporal weight, food intake, serum protein, vitamin A, immunology indicators and histology evaluation (spleen, thymus and liver). Protein deficiency generated a significant decrease of the expression gene of Interleukin 1. Atrophy signs in lymphoid tissues and morphologic changes in the liver were associated with the dietary protein utilization. Protein and vitamin A deficiency generated significant stimulation of the Interleukin 1 expression gene with increase of the level of the inflammatory state indicators as serum alpha protein, total complement and neutrophils. This stimulation could be generated by a deficient retinol mobilization to tissues. These results support the hypothesis of the function of cytokines as mediators of subclinical symptoms of the immune system during the nutritional affectations. 相似文献
165.
Alberto Canfrn-Duque
scar Pastor David García-Seisdedos Yessenia L. Molina Bohdan Babiy Milagros Lerma Carmen Snchez-Castellano Javier Martínez-Botas Diego Gmez-Coronado Miguel A. Lasuncin Alfonso J. Cruz-Jentoft Rebeca Busto 《International journal of molecular sciences》2021,22(8)
Atypical or second-generation antipsychotics are used in the treatment of psychosis and behavioral problems in older persons with dementia. However, these pharmaceutical drugs are associated with an increased risk of stroke in such patients. In this study, we evaluated the effects of risperidone treatment on phospholipid and sphingolipid composition and lipid raft function in peripheral blood mononuclear cells (PBMCs) of older patients (mean age >88 years). The results showed that the levels of dihydroceramides, very-long-chain ceramides, and lysophosphatidylcholines decreased in PBMCs of the risperidone-treated group compared with untreated controls. These findings were confirmed by in vitro assays using human THP-1 monocytes. The reduction in the levels of very-long-chain ceramides and dihydroceramides could be due to the decrease in the expression of fatty acid elongase 3, as observed in THP-1 monocytes. Moreover, risperidone disrupted lipid raft domains in the plasma membrane of PBMCs. These results indicated that risperidone alters phospholipid and sphingolipid composition and lipid raft domains in PBMCs of older patients, potentially affecting multiple signaling pathways associated with these membrane domains. 相似文献
166.
Ana Montero-Calle Itziar Aranguren-Abeigon María Garranzo-Asensio Carmen Poves María Jesús Fernández-Ace?ero Javier Martínez-Useros Rodrigo Sanz Jana Dziaková Javier Rodriguez-Cobos Guillermo Solís-Fernández Eloy Povedano Maria Gamella Rebeca Magnolia Torrente-Rodríguez Miren Alonso-Navarro Vivian de los Ríos J.Ignacio Casal Gemma Domínguez Ana Guzman-Aranguez Alberto Peláez-García José Manuel Pingarrón Susana Campuzano Rodrigo Barderas 《工程(英文)》2021,7(10):1393-1412
Colorectal cancer (CRC) is the second leading cause of cancer-related death worldwide. The five-year survival rate of CRC patients depends on the stage at diagnosis, being higher than 80% when CRC is diagnosed in the early stages but lower than 10% when CRC is diagnosed in advanced stages. Autoantibodies against specific CRC autoantigens (tumor-associated antigens (TAAs)) in the sera of patients have been widely demonstrated to aid in early diagnosis. Thus, we herein aim to identify autoantigens target of autoantibodies specific to CRC that possess a significant ability to discriminate between CRC patients and healthy individuals by means of liquid biopsy. To that end, we examined the protein content of the exosomes released by five CRC cell lines and tissue samples from CRC patients by means of immunoprecipitation coupled with mass spectrometry analysis. A total of 103 proteins were identified as potential autoantigens specific to CRC. After bioinformatics and meta-analysis, we selected 15 proteins that are more likely to be actual CRC autoantigens in order to evaluate their role in CRC prognosis by Western blot (WB) and immunohistochemistry (IHC). We found dysregulation at the protein level for 11 of these proteins in both tissue and plasma exosome samples from patients, along with an association of nine of these proteins with CRC prognosis. After validation, all but one showed a statistically significant high diagnostic ability to distinguish CRC patients and individuals with premalignant lesions from healthy individuals, either by luminescence Halotag-based beads, or by a multiplexed biosensing platform involving the use of magnetic microcarriers as solid support modified with covalently immobilized Halotag fusion proteins constructed for CRC detection. Taken together, our results highlight the usefulness of the approach defined here to identify the TAAs specific to chronic diseases; they also demonstrate that the measurement of autoantibody levels in plasma against the TAAs identified here could be integrated into a point-of-care (POC) device for CRC detection with high diagnostic ability. 相似文献
167.
168.
Rubn Núez Csar Domínguez Stephen Askins Marta Victoria Rebeca Herrero Ignacio Antn Gabriel Sala 《Progress in Photovoltaics: Research and Applications》2016,24(5):663-679
A methodology is presented to determine both the short‐term and the long‐term influence of the spectral variations on the performance of multi‐junction (MJ) solar cells and concentrator photovoltaic (CPV) modules. Component cells with the same optical behavior as MJ solar cells are used to characterize the spectrum. A set of parameters, namely spectral matching ratios (SMRs), is used to characterize spectrally a particular direct normal irradiance (DNI) by comparison to the reference spectrum (AM1.5D‐ASTM‐G173‐03). Furthermore, the spectrally corrected DNI for a given MJ solar cell technology is defined providing a way to estimate the losses associated to the spectral variations. The last section analyzes how the spectrum evolves throughout a year in a given place and the set of SMRs representative for that location are calculated. This information can be used to maximize the energy harvested by the MJ solar cell throughout the year. As an example, three years of data recorded in Madrid shows that losses lower than 5% are expected because of current mismatch for state‐of‐the‐art MJ solar cells. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
169.
Romina Bellingeri Fabrisio Alustiza Natalia Picco Diego Acevedo Maria Alejandra Molina Rebeca Rivero Carolina Grosso Carlos Motta Cesar Barbero Adriana Vivas 《应用聚合物科学杂志》2015,132(5)
Composite materials based on carbon nanotubes (CNT) and polymeric hydrogels have become the subject matter of major interest for use as carriers in drug delivery research. The aim of this study was to evaluate the in vitro cytotoxicity of the hydrogel–carbon nanotube–chitosan (hydrogel–CNT–CH) composites on intestinal cells. Oxidized CNT were wrapped with chitosan (CH), Fourier transform infrared (FT‐IR) analysis suggest that oxidized CNT interact with CH. Transmission electron microscopy (TEM) images show a CH layer lying around CNT. Chitosan wrapped CNT were incorporated to poly (acrylamide‐co‐acrylic acid) hydrogels. Swelling behavior in buffers at different pH were evaluated and revealed a significantly lower swelling when it is exposed to a acid buffer solution (pH 2.2). Mechanical properties were evaluated by measurements of elasticity and the material with CNT showed better mechanical properties. The incorporation and liberation of Egg Yolk Immunoglobulin from hydrogel–CNT–CH were also assessed and it revealed an improved performance. To evaluate the effect of these nanocomposites on cellular redox balance, intestinal cells were exposed to hydrogel–CNT–CH composites and antioxidant enzymes were assessed. Cytotoxicity and apoptosis were also evaluated. Hydrogel–CNT–CH composites induce no oxidative stress and there were no evidence of cytotoxicity or cell death. These preliminary findings suggest that hydrogel–CNT–CH composites show improved properties and good biocompatibility in vitro making these biomaterials promising systems for drug delivery purposes. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41370. 相似文献
170.