Fractal Spectrum of a Quasi_periodically Driven Spin System

We numerically perform a spectral analysis of a quasi-periodically driven spin 1/2 system, the spectrum of which is Singular Continuous. We compute fractal dimensions of spectral measures and discuss their connections with the time behaviour of various dynamical quantities, such as the moments of the distribution of the wave packet. Our data suggest a close similarity between the information dimension of the spectrum and the exponent ruling the algebraic growth of the 'entropic width' of wavepackets.Comment: 17 pages, RevTex, 5 figs. available on request from [email protected]

Unraveling the performance of dispersion-corrected functionals for the accurate description of weakly bound natural polyphenols

Long-range non-covalent interactions play a key role in the chemistry of natural polyphenols. We have previously proposed a description of supramolecular polyphenol complexes by the B3P86 density functional coupled with some corrections for dispersion. We couple here the B3P86 functional with the D3 correction for dispersion, assessing systematically the accuracy of the new B3P86-D3 model using for that the well-known S66, HB23, NCCE31, and S12L datasets for non-covalent interactions. Furthermore, the association energies of these complexes were carefully compared to those obtained by other dispersion-corrected functionals, such as B(3)LYP-D3, BP86-D3 or B3P86-NL. Finally, this set of models were also applied to a database composed of seven non-covalent polyphenol complexes of the most interest.FDM acknowledges financial support from the Swedish Research Council (Grant No. 621-2014-4646) and SNIC (Swedish National Infrastructure for Computing) for providing computer resources. The work in Limoges (IB and PT) is supported by the “Conseil Régional du Limousin”. PT gratefully acknowledges the support by the Operational Program Research and Development Fund (project CZ.1.05/2.1.00/03.0058 of the Ministry of Education, Youth and Sports of the Czech Republic). IB gratefully acknowledges financial support from “Association Djerbienne en France”

Physical activity programs in older persons with Alzheimer’s disease: a need for dedicated trials

Recent works highlight the influence of different aspects of lifestyle on cognitive decline and the risk of dementia. Some data suggest that exercise could improve cognitive performance, especially executive functions and reduce the risk of cognitive decline and dementia in the elder. There is controversial data regarding the role of physical exercise on cognitive performance in older patients with dementia, which may be due to diverse study designs. Innovative interventional trials need to adapt their aims toward physical and cognitive changes in patients suffering from Alzheimer's disease (AD) in association with physical activity (PA). Future goals should include specific Adapted Physical Activity (APA) intervention programs on maintaining cognitive, emotional, and physical function in older persons with dementia at risk of rapid decline. In this commentary, we will provide novel insights on the use of potential physical activity programs in Alzheimer's Disease Day Centers

Harmful and Beneficial Role of ROS 2020

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Physiological mechanisms and adaptation strategies of Lactuca sativa L. in response to Olea europaea L. and Ficus carica L. allelochemicals

Agro-industrial wastes of Ficus carica L. and Olea europaea L. represent great sources of bioactive phenolic compounds that would be actively involved in sustainable development. Most of these wastes possess a valuable source of phytotoxic compounds that would be used as potential bioherbicides, but their function and mechanisms of action in cultivated crops remain far to be understood. In this study, we investigate the biochemical and physiological mechanisms of action of fig and olive allelochemicals extracts in lettuce as a model plant for weed species studies. Results revealed that these allelochemicals triggered an oxidative stress through cell membrane damage in lettuce roots and leaves, which was mitigated by various adaptive responses. Therefore, an intricate defense system was implicated by the increase of enzymatic and non-enzymatic antioxidants in lettuce tissues. This adaptive physiological response was highly correlated with the regulation of the phenylpropanoid pathway through the distinguished activation of phenylalanine ammonia-lyase by 98% and phenolic accumulation by 85% under olive and fig leaves aqueous extracts. The outcomes of this study will help understanding the response of cultivated crop to fig and olive phenolic compounds that can be selective in their actions, or the plants can be selective in their responses

Clinical, biochemical, and genetic features associated with VARS2-related mitochondrial disease

In recent years, an increasing number of mitochondrial disorders have been associated with mutations in mitochondrial aminoacyl-tRNA synthetases (mt-aaRSs), which are key enzymes of mitochondrial protein synthesis. Bi-allelic functional variants in VARS2, encoding the mitochondrial valyl tRNA-synthetase, were first reported in a patient with psychomotor delay and epilepsia partialis continua associated with an oxidative phosphorylation (OXPHOS) Complex I defect, before being described in a patient with a neonatal form of encephalocardiomyopathy. Here we provide a detailed genetic, clinical, and biochemical description of 13 patients, from nine unrelated families, harboring VARS2 mutations. All patients except one, who manifested with a less severe disease course, presented at birth exhibiting severe encephalomyopathy and cardiomyopathy. Features included hypotonia, psychomotor delay, seizures, feeding difficulty, abnormal cranial MRI, and elevated lactate. The biochemical phenotype comprised a combined Complex I and Complex IV OXPHOS defect in muscle, with patient fibroblasts displaying normal OXPHOS activity. Homology modeling supported the pathogenicity of VARS2 missense variants. The detailed description of this cohort further delineates our understanding of the clinical presentation associated with pathogenic VARS2 variants and we recommend that this gene should be considered in early-onset mitochondrial encephalomyopathies or encephalocardiomyopathies.Peer reviewe

Identifying time patterns of highland and lowland air temperature trends in Italy and the UK across monthly and annual scales

This paper presents a statistical analysis of air temperature data from 32 stations in Italy and the UK up to 2000 m above sea level from 2002 to 2021. The data came from both highland and lowland areas in order to evaluate the differences due to both location and elevation. The analysis focused on detecting trends at annual and monthly timescales, employing ordinary least-squares (OLS), robust S-estimator regression, and Mann–Kendall (MK) and Sen's slope methods. Hierarchical clustering (HCA) using dynamic time warping (DTW) was then applied to the monthly data to analyze the intra-annual pattern similarity of trends within and across the groups. Two different regions of Europe were chosen because of the different climate and temperature trends – namely, the northern UK (smaller trends) and the northwest Italian Alps (larger trends). The main novelty of the work is to show that stations with similar locations and altitudes have similar monthly slopes by quantifying them using DTW and clustering. These results reveal the nonrandomness of different trends throughout the year and between different parts of Europe, with a modest influence of altitude in wintertime. The findings revealed that group average trends were close to the National Oceanic and Atmospheric Administration (NOAA) values for the areas in Italy and the UK, confirming the validity of analyzing a small number of stations. More interestingly, intra-annual patterns were detected commonly at the stations of each of the groups and are clearly different between them. Confirming the different climates, most highland and lowland stations in Italy exhibit statistically significant positive trends, while in the UK, both highland and lowland stations show statistically nonsignificant negative trends. Hierarchical clustering in combination with DTW showed consistent similarity between monthly patterns of means and trends within the group of stations and inconsistent similarity between patterns across groups. The use of the 12 distance correlation matrices (dcor) (one for each month) also contributes to what is the main result of the paper, which is to clearly show the different temporal patterns in relation to location and (in some months) altitude. The anomalous behaviors detected at 3 of the 32 stations, namely Valpelline, Fossano, and Aonoch Mòr, can be attributed, respectively, to the facts that Valpelline is the lowest-elevation station in its group; Fossano is the southernmost of the Italian stations, with some sublittoral influence; and Aonoch Mòr has a large number of missing values. In conclusion, these results improve our understanding of temperature spatio-temporal dynamics in two very different regions of Europe and emphasize the importance of consistent analysis of data to assess the ongoing effects of climate change. The intra-annual time patterns of temperature trends could also be compared with climate model results.</p