151 research outputs found

    Complexity analysis of Klein-Gordon single-particle systems

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    The Fisher-Shannon complexity is used to quantitatively estimate the contribution of relativistic effects to on the internal disorder of Klein-Gordon single-particle Coulomb systems which is manifest in the rich variety of three-dimensional geometries of its corresponding quantum-mechanical probability density. It is observed that, contrary to the non-relativistic case, the Fisher-Shannon complexity of these relativistic systems does depend on the potential strength (nuclear charge). This is numerically illustrated for pionic atoms. Moreover, its variation with the quantum numbers (n, l, m) is analysed in various ground and excited states. It is found that the relativistic effects enhance when n and/or l are decreasing.Comment: 4 pages, 3 figures, Accepted in EPL (Europhysics Letters

    Contexto geomorfológico y principales rasgos tecnológicos de nuevos yacimientos del Pleistoceno Medio y Superior en el Valle Inferior del Manzanares (Madrid, España)

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    The archaeological works developed during the years 1996 in the site of Tafesa, 2005 in the 12 de Octubre Metro Station site and 2006 in the confluence of the Butarque Stream (Villaverde-Barrio de Butarque site) located south of the Madrid City (Spain), have provided new lithic assemblages. These assemblages have been stratigraphically contextualized in the Pleistocene deposits of the Lower Manzanares river valley within the so-called “Manzanares Complex Terrace” (TCMZ). This fluvial terrace constitutes an anomalous thickened (20-15m) deposit at +22-16m above the present river thalweg mainly developed along the right (southern) valley margin. This fluvial level has been traditionally considered of middle Pleistocene age on the basis of the acheulian lithics and faunal assemblages typically located within its lower stratigraphic layers. Certainly, the Tafesa is a fluvial terrace site at +22 m with acheulian industry and middle Pleistocene faunal remains at its lower sedimentary sequence. However, the upper sedimentary levels of this same terrace in the 12 de Octubre y Villaverde-Butarque sites throw lithic assemblages of the lower and upper Paleolithic belonging to upper Pleistocene, as suggested by the available set of TL and OSL dates for the zone. The analyses developed in this study indicate that the development of this thickened fluvial terrace started during the end of the middle Pleistocene, but also comprise the whole Oxygen Isotopic Stage OIS 5 during the upper Pleistocene.Las intervenciones arqueológicas llevadas a cabo durante los años 1996 en Tafesa, 2005 en el yacimiento Hospital 12 de Octubre y 2006 en la desembocadura del arroyo Butarque (Villaverde-Barrio de Butarque) situados al sur de la ciudad de Madrid (España), han aportado nuevos conjuntos líticos contextualizados estratigráficamente en los depósitos fluviales pleistocenos correspondientes al tramo inferior del valle del río Manzanares. Los yacimientos arqueológicos analizados se sitúan geomorfológicamente en la denominada “Terraza Compleja del Manzanares” (TCMZ), la cual constituye un nivel fluvial engrosado (20-15 m de potencia) situado entre +22-16 m sobre el cauce actual del río, a lo largo de su margen derecha. Este nivel fluvial ha sido tradicionalmente considerado de edad Pleistoceno medio en base a la industria achelense y complejos faunísticos encontrados en sus niveles inferiores. Ciertamente, Tafesa es un yacimiento situado en la parte inferior-media de la terraza de +22 m con industria achelense y fauna de Pleistoceno medio. Por el contrario, los niveles superiores de esta misma terraza en los sectores del 12 de Octubre y Villaverde-Butarque se encuentran asociados a industrias del Paleolítico inferior y medio ya pertenecientes al Pleistoceno superior, como sugieren el conjunto de dataciones OSL y TL existentes para la zona. Los datos analizados en este trabajo indican que el desarrollo de este nivel de terraza engrosado comienza durante la parte final de Pleistoceno medio y abarca todo el Estadio Isotópico OIS 5, ya dentro del Pleistoceno superior

    Configuration Complexities of Hydrogenic Atoms

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    The Fisher-Shannon and Cramer-Rao information measures, and the LMC-like or shape complexity (i.e., the disequilibrium times the Shannon entropic power) of hydrogenic stationary states are investigated in both position and momentum spaces. First, it is shown that not only the Fisher information and the variance (then, the Cramer-Rao measure) but also the disequilibrium associated to the quantum-mechanical probability density can be explicitly expressed in terms of the three quantum numbers (n, l, m) of the corresponding state. Second, the three composite measures mentioned above are analytically, numerically and physically discussed for both ground and excited states. It is observed, in particular, that these configuration complexities do not depend on the nuclear charge Z. Moreover, the Fisher-Shannon measure is shown to quadratically depend on the principal quantum number n. Finally, sharp upper bounds to the Fisher-Shannon measure and the shape complexity of a general hydrogenic orbital are given in terms of the quantum numbers.Comment: 22 pages, 7 figures, accepted i

    Programming Skeletal Muscle Metabolic Flexibility in Offspring of Male Rats in Response to Maternal Consumption of Slow Digesting Carbohydrates during Pregnancy

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    Skeletal muscle plays a relevant role in metabolic flexibility and fuel usage and the associated muscle metabolic inflexibility due to high-fat diets contributing to obesity and type 2 diabetes. Previous research from our group indicates that a high-fat and rapid-digesting carbohydrate diet during pregnancy promotes an excessive adipogenesis and also increases the risk of non-alcoholic fatty liver disease in the offspring. This effect can be counteracted by diets containing carbohydrates with similar glycemic load but lower digestion rates. To address the role of the skeletal muscle in these experimental settings, pregnant rats were fed high-fat diets containing carbohydrates with similar glycemic load but different digestion rates, a high fat containing rapid-digesting carbohydrates diet (HF/RD diet) or a high fat containing slow-digesting carbohydrates diet (HF/SD diet). After weaning, male offspring were fed a standard diet for 3 weeks (weaning) or 10 weeks (adolescence) and the impact of the maternal HF/RD and HF/SD diets on the metabolism, signaling pathways and muscle transcriptome was analyzed. The HF/SD offspring displayed better muscle features compared with the HF/RD group, showing a higher muscle mass, myosin content and differentiation markers that translated into a greater grip strength. In the HF/SD group, metabolic changes such as a higher expression of fatty acids (FAT/CD36) and glucose (GLUT4) transporters, an enhanced glycogen content, as well as changes in regulatory enzymes such as muscle pyruvate kinase and pyruvate dehydrogenase kinase 4 were found, supporting an increased muscle metabolic flexibility and improved muscle performance. The analysis of signaling pathways was consistent with a better insulin sensitivity in the muscle of the HF/SD group.This research was funded by European Union’s Seventh Framework Programme (FP7/2007–2013): project Early Nutrition, under grant agreement no. 289346

    Quantum Fluctuation Theorems

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    Recent advances in experimental techniques allow one to measure and control systems at the level of single molecules and atoms. Here gaining information about fluctuating thermodynamic quantities is crucial for understanding nonequilibrium thermodynamic behavior of small systems. To achieve this aim, stochastic thermodynamics offers a theoretical framework, and nonequilibrium equalities such as Jarzynski equality and fluctuation theorems provide key information about the fluctuating thermodynamic quantities. We review the recent progress in quantum fluctuation theorems, including the studies of Maxwell's demon which plays a crucial role in connecting thermodynamics with information.Comment: As a chapter of: F. Binder, L. A. Correa, C. Gogolin, J. Anders, and G. Adesso (eds.), "Thermodynamics in the quantum regime - Fundamental Aspects and New Directions", (Springer International Publishing, 2018

    HCC risk stratification after cure of hepatitis C in patients with compensated advanced chronic liver disease

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    Background&Aims: Hepatocellular carcinoma (HCC) is a main cause of morbidity and mortality in patients with advanced chronic liver disease (ACLD) due to chronic hepatitis C and who have achieved sustained virologic response (SVR). We elaborated risk stratification algorithms for de-novo-HCC-development after SVR and validated them in an independent cohort. Methods: Derivation cohort: 527 patients with pre-treatment ACLD and SVR to interferon-free therapy were evaluated for de-novo-HCC-development. Among others, alpha-fetoprotein (AFP) and non-invasive surrogates of portal hypertension including liver stiffness measurement (LSM) were assessed pre-/post-treatment. Validation cohort: 1500 patients with compensated ACLD (cACLD) from other European centers. Results: During a median follow-up (FU) of 41 months, 22/475 cACLD (4.6%) (1.45/100patient-years)vs.12/52 decompensated patients (23.1%, 7.00/100patient-years, p<0.001) developed de-novo-HCC. Since decompensated patients were at substantial HCC-risk, we focused on cACLD for all further analyses. In cACLD, post-treatment-values showed a higher discriminative ability for patients with/without de-novo-HCC-development during FU than pre-treatment-values or absolute/relative changes. Models based on post-treatment AFP≥4.6ngxmL-1-3points, alcohol consumption (males:>30g/d/females:>20g/d)-2points (optional), age≥59year-2points, LSM≥19.0kPa-1point, and albumin<42gxL-1-1point, accurately predicted de-novo-HCC-development (bootstrapped Harrel’s C with and without considering alcohol:0.893 and 0.836). Importantly, these parameters also provided independent prognostic information in competing risk analysis and accurately stratified patients into low-(0-3points; ≈2/3 of patients) and high-risk (≥4points; ≈1/3) groups in the derivation (algorithm with alcohol consumption; 4-year HCC-risk:0%vs.16.5%) and validation (3.3%/17.5%) cohorts. An alternative approach based on age/alcohol (optional)/FU-LSM/FU-albumin (i.e., without FU-AFP) also showed a robust performance. Conclusions: Simple algorithms based on post-treatment age/albumin/LSM, and optionally, AFP and alcohol, accurately stratified de-novo-HCC-risk in cACLD patients with SVR. Approximately 2/3 were identified as having an HCC-risk <1%/y in both the derivation and validation cohort, thereby clearly falling below the cost-effectiveness threshold for HCC-surveillance. LAY SUMMARY: Simple algorithms based on age, alcohol consumption, results of blood tests (albumin and α-fetoprotein), as well as liver stiffness measurement after the end of hepatitis C treatment identify a large proportion (approximately 2/3) of patients with advanced but still asymptomatic liver disease who are at very low risk (<1%/year) of liver cancer development, and thus, might not need to undergo 6-monthly liver ultrasound

    Pharmacovigilance in children in Camagüey Province, Cuba

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    Purpose: Our aim was to describe the adverse drug reactions (ADRs) detected following increased education about pharmacovigilance and drug toxicity in children in Camagüey Province, Cuba. Methods: Over a period of 24 months (January 2009 to December 2010), all reports of suspected ADRs in children to the Provincial Pharmacovigilance Centre in Camagüey Province were analysed. ADRs were classified in relation to causality and severity. Results: There were 533 reports involving suspected ADRs in children in the period. Almost one third of the reports received were classified as moderate (155, 29%) or severe (10, 2%). There was one fatality in association with the use of ceftriaxone. Vaccines and antibiotics were responsible for most of the ADR reports (392, 74%) and for all ten severe ADRs. After an intensive educational package, both within the community and the Children’s Hospital, the number of reports increased from 124 in 2008 to 161 in 2009 and 372 in 2010. This was equivalent to a reporting rate of 879 and 2,031 reports per million children per year for 2009 and 2010, respectively. Conclusions: The incidence of ADRs in children Camagüey Province, Cuba, is greater than previously reported. An educational intervention about pharmacovigilance and drug toxicity in children can improve the reporting of ADRs

    β-Hydroxy-β-Methylbutyrate (HMB) Normalizes Dexamethasone-Induced Autophagy-Lysosomal Pathway in Skeletal Muscle

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    Dexamethasone-induced muscle atrophy is due to an increase in protein breakdown and a decrease in protein synthesis, associated with an over-stimulation of the autophagy-lysosomal pathway. These effects are mediated by alterations in IGF-1 and PI3K/Akt signaling. In this study, we have investigated the effects of β-Hydroxy-β-methylbutyrate (HMB) on the regulation of autophagy and proteosomal systems. Rats were treated during 21 days with dexamethasone as a model of muscle atrophy. Co-administration of HMB attenuated the effects promoted by dexamethasone. HMB ameliorated the loss in body weight, lean mass and the reduction of the muscle fiber cross-sectional area (shrinkage) in gastrocnemius muscle. Consequently, HMB produced an improvement in muscle strength in the dexamethasone-treated rats. To elucidate the molecular mechanisms responsible for these effects, rat L6 myotubes were used. In these cells, HMB significantly attenuated lysosomal proteolysis induced by dexamethasone by normalizing the changes observed in autophagosome formation, LC3 II, p62 and Bnip3 expression after dexamethasone treatment. HMB effects were mediated by an increase in FoxO3a phosphorylation and concomitant decrease in FoxO transcriptional activity. The HMB effect was due to the restoration of Akt signaling diminished by dexamethasone treatment. Moreover, HMB was also involved in the regulation of the activity of ubiquitin and expression of MurF1 and Atrogin-1, components of the proteasome system that are activated or up-regulated by dexamethasone. In conclusion, in vivo and in vitro studies suggest that HMB exerts protective effects against dexamethasone-induced muscle atrophy by normalizing the Akt/FoxO axis that controls autophagy and ubiquitin proteolysis.This project has been funded by Abbott Nutrition R&D

    β-Hydroxy-β-Methylbutyrate (HMB) Promotes Neurite Outgrowth in Neuro2a Cells

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    β-Hydroxy-β-methylbutyrate (HMB) has been shown to enhance cell survival, differentiation and protein turnover in muscle, mainly activating phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) and mitogen-activated protein kinases/ extracellular-signal-regulated kinases (MAPK/ERK) signaling pathways. Since these two pathways are related to neuronal survival and differentiation, in this study, we have investigated the neurotrophic effects of HMB in mouse neuroblastoma Neuro2a cells. In Neuro2a cells, HMB promotes differentiation to neurites independent from any effects on proliferation. These effects are mediated by activation of both the PI3K/Akt and the extracellular-signal-regulated kinases (ERK1/2) signaling as demonstrated by the use of specific inhibitors of these two pathways. As myocyte-enhancer factor 2 (MEF2) family of transcription factors are involved in neuronal survival and plasticity, the transcriptional activity and protein levels of MEF2 were also evaluated. HMB promoted MEF2-dependent transcriptional activity mediated by the activation of Akt and ERK1/2 pathways. Furthermore, HMB increases the expression of brain glucose transporters 1 (GLUT1) and 3 (GLUT3), and mTOR phosphorylation, which translates in a higher protein synthesis in Neuro2a cells. Furthermore, Torin1 and rapamycin effects on MEF2 transcriptional activity and HMB-dependent neurite outgrowth support that HMB acts through mTORC2. Together, these findings provide clear evidence to support an important role of HMB in neurite outgrowth.This project has been funded by Abbott Nutrition R&D
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