L. has been cultivated throughout history to obtain its flowers, whose dried stigmas give rise to the spice known as saffron. Crocetin esters, picrocrocin, and safranal are the main metabolites of ...this spice, which possess a great bioactivity, although the mechanisms of action and its bioavailability are still to be solved. The rest of the flower is composed by style, tepals, and stamens that have other compounds, such as kaempferol and delphinidin, which have an important antioxidant capacity, and these can be applied in foods, phytopharmaceuticals, and cosmetics. The aim of this work was to provide an updated and critical review of the research on the main compounds of
L. flower, including the adequate analytical methods for their identification and quantification, with a focus on their bioactivity and bioavailability.
Forest production efficiency (FPE) metric describes how efficiently the assimilated carbon is partitioned into plants organs (biomass production, BP) or-more generally-for the production of organic ...matter (net primary production, NPP). We present a global analysis of the relationship of FPE to stand-age and climate, based on a large compilation of data on gross primary production and either BP or NPP. FPE is important for both forest production and atmospheric carbon dioxide uptake. We find that FPE increases with absolute latitude, precipitation and (all else equal) with temperature. Earlier findings-FPE declining with age-are also supported by this analysis. However, the temperature effect is opposite to what would be expected based on the short-term physiological response of respiration rates to temperature, implying a top-down regulation of carbon loss, perhaps reflecting the higher carbon costs of nutrient acquisition in colder climates. Current ecosystem models do not reproduce this phenomenon. They consistently predict lower FPE in warmer climates, and are therefore likely to overestimate carbon losses in a warming climate.
Among the major factors controlling soil erosion, as vegetation cover or soil erodibility, rainfall erosivity has a paramount importance since it is difficult to predict and control by humans. ...Accurate estimation of rainfall erosivity requires continuous rainfall data; however, such data rarely demonstrate good spatial and temporal coverage. Daily weather records are now commonly available, providing good coverage that better represents rainfall intensity behavior than do more aggregated rainfall data. In the present study annual rainfall erosivity was estimated from daily rainfall records, and compared to data obtained employing the RUSLE
R factor procedure. A spatially-dense precipitation database of high temporal resolution (15
min) was used. Two methodologies were applied: (i) daily rainfall erosivity estimated using several parametric models, and, (ii) annual rainfall erosivity estimated by regression-based techniques employing several intensity precipitation indices and the modified Fournier index. To determine the accuracy of estimates, several goodness-of-fit and error statistics were computed in addition to a spatial distribution comparison. The daily rainfall erosivity models accurately predicted annual rainfall erosivity. Parametric models with few combined parameters and a periodic function simulating intra-annual rainfall behavior provided the best results. Where daily rainfall records were not available, good estimates of annual rainfall erosivity were also obtained using regression-based techniques based on 5-day maximum precipitation events, the maximum wet spell duration, and the ratio between the lengths of average wet and dry spells. Inherent limitations remain in the use of daily weather records for estimating rainfall erosivity. Future research should focus on incorporating measures of natural rainfall properties of the particular region, including kinetic energy and intensity, and their effects on the soil.
In the region of Murcia (southeast Spain), sweet pepper has been grown as a monoculture in greenhouses for many years. Until 2005, when it was banned, soils were disinfested with methyl bromide (MB) ...to control pathogens and to prevent soil fatigue effects. The genus Fusarium plays an important role in the microbiological component associated with yield decline in pepper monocultures. In the present study, soils were treated with manure amendments, alone (biofumigation, B) or in combination with solarization (biosolarization, BS), with or without the addition of pepper plant residues. The B and BS treatments were compared with a treatment using MB. The extent of disinfestation was measured from the density of Fusarium spp. isolated from the soil before and after the respective treatments. Three different species were systematically isolated: Fusarium oxysporum, Fusarium solani and Fusarium equiseti. The repeated use of manure amendments with pepper crop residues, without solarization, was unable to decrease the Fusarium spp. density (which increased from 2,047.17 CFU g⁻¹ to 3,157.24 CFU g⁻¹ before and after soil disinfestation, respectively), unlike MB-treated soil (in which the fungi decreased from 481.39 CFU g⁻¹ to 23.98 CFU g⁻¹). However, the effectiveness of the repeated application of BS in diminishing doses (with or without adding plant residues) on Fusarium populations (reductions greater than 72%) was similar to or even greater than the effect of MB.
In this paper, we explore the (in)efficiency of the continuum Bitcoin-USD market in the period ranging from mid 2010 to early 2019. To deal with, we dynamically analyse the evolution of the ...self-similarity exponent of Bitcoin-USD daily returns via accurate FD4 approach by a 512 day sliding window with overlapping data. Further, we define the memory indicator by the difference between the self-similarity exponent of Bitcoin-USD series and the self-similarity index of its shuffled series. We also carry out additional analyses via FD4 approach by sliding windows of sizes equal to 64, 128, 256, and 1024 days, and also via FD algorithm for values of q equal to 1 and 2 (and sliding windows equal to 512 days). Moreover, we explored the evolution of the self-similarity exponent of actual S&P500 series via FD4 algorithm by sliding windows of sizes equal to 256 and 512 days. In all the cases, the obtained results were found to be similar to our first analysis. We conclude that the self-similarity exponent of the BTC-USD (resp., S&P500) series stands above 0.5. However, this is not due to the presence of significant memory in the series but to its underlying distribution. In fact, it holds that the self-similarity exponent of BTC-USD (resp., S&P500) series is similar or lower than the self-similarity index of a random series with the same distribution. As such, several periods with significant antipersistent memory in BTC-USD (resp., S&P500) series are distinguished.
The goal of this paper is to analyse the innovation activity convergence process across European regions from 2002 to 2012. A novel methodology that allows either detection of overall convergence or ...endogenous identification of groups of regions was applied. The results support the club convergence hypothesis for explaining the convergence process of Europe's regions during the period analysed and seven innovation convergence clubs were identified. In addition, the research results indicate that initial regional R&D expenditure is the most relevant factor driving the formation of the convergence clubs after controlling for the effects of regional structural characteristics.
Resumen
El objetivo de este artículo es analizar el proceso de convergencia de las actividades de innovación en las regiones europeas desde 2002 a 2012. Se aplicó una metodología novedosa que permite la detección de la convergencia total o la identificación endógena de grupos de regiones. Los resultados apoyan la hipótesis de clubes de convergencia para explicar el proceso de convergencia de las regiones de Europa durante el período analizado y se identificaron siete clubes de convergencia en cuanto a innovación. Además, los resultados de la investigación indican que el gasto inicial en I+D regional es el factor más importante a la hora de impulsar la formación de los clubes de convergencia, una vez que se han controlado los efectos de las características estructurales regionales.
抄録:
本稿の目的は、2002~2012年のヨーロッパの地域全体における、イノベーション活動の収束の過程を分析することである。全体的収束の検出または地域の内因性同定のいずれかが可能な新しい方法を適用した。結果から、解析の対象期間におけるヨーロッパの地域の収束仮定を説明するクラブ収束仮設が支持され、7つのイノベーション収束クラブが確認された。さらに、結果から、地域の構造的特徴の影響を調整した後では、収束クラブの形成を促す最も重要な要因は、地域のはじめの研究開発資金であることが示された。
Background: Patients with chronic obstructive pulmonary disease (COPD) often present with severe acute exacerbations requiring hospital treatment. However, little is known about the prognostic ...consequences of these exacerbations. A study was undertaken to investigate whether severe acute exacerbations of COPD exert a direct effect on mortality. Methods: Multivariate techniques were used to analyse the prognostic influence of acute exacerbations of COPD treated in hospital (visits to the emergency service and admissions), patient age, smoking, body mass index, co-morbidity, long term oxygen therapy, forced spirometric parameters, and arterial blood gas tensions in a prospective cohort of 304 men with COPD followed up for 5 years. The mean (SD) age of the patients was 71 (9) years and forced expiratory volume in 1 second was 46 (17)%. Results: Only older age (hazard ratio (HR) 5.28, 95% CI 1.75 to 15.93), arterial carbon dioxide tension (HR 1.07, 95% CI 1.02 to 1.12), and acute exacerbations of COPD were found to be independent indicators of a poor prognosis. The patients with the greatest mortality risk were those with three or more acute COPD exacerbations (HR 4.13, 95% CI 1.80 to 9.41). Conclusions: This study shows for the first time that severe acute exacerbations of COPD have an independent negative impact on patient prognosis. Mortality increases with the frequency of severe exacerbations, particularly if these require admission to hospital.
Methionine adenosyltransferase 1A (MAT1A) and glycine N‐methyltransferase (GNMT) are the primary genes involved in hepatic S‐adenosylmethionine (SAMe) synthesis and degradation, respectively. Mat1a ...ablation in mice induces a decrease in hepatic SAMe, activation of lipogenesis, inhibition of triglyceride (TG) release, and steatosis. Gnmt‐deficient mice, despite showing a large increase in hepatic SAMe, also develop steatosis. We hypothesized that as an adaptive response to hepatic SAMe accumulation, phosphatidylcholine (PC) synthesis by way of the phosphatidylethanolamine (PE) N‐methyltransferase (PEMT) pathway is stimulated in Gnmt−/− mice. We also propose that the excess PC thus generated is catabolized, leading to TG synthesis and steatosis by way of diglyceride (DG) generation. We observed that Gnmt−/− mice present with normal hepatic lipogenesis and increased TG release. We also observed that the flux from PE to PC is stimulated in the liver of Gnmt−/− mice and that this results in a reduction in PE content and a marked increase in DG and TG. Conversely, reduction of hepatic SAMe following the administration of a methionine‐deficient diet reverted the flux from PE to PC of Gnmt−/− mice to that of wildtype animals and normalized DG and TG content preventing the development of steatosis. Gnmt−/− mice with an additional deletion of perilipin2, the predominant lipid droplet protein, maintain high SAMe levels, with a concurrent increased flux from PE to PC, but do not develop liver steatosis. Conclusion: These findings indicate that excess SAMe reroutes PE towards PC and TG synthesis and lipid sequestration. (Hepatology 2013;58:1296–1305)
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