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Sara García‐Condado Raúl Lpez‐Lozano Lorenzo Panarello Iacopo Cerrani Luigi Nisini Antonio Zucchini Marijn Van der Velde Bettina Baruth 《Global Change Biology Bioenergy》2019,11(6):809-831
This study assesses crop residues in the EU from major crops using empirical models to predict crop residues from yield statistics; furthermore it analyses the inter‐annual variability of those estimates over the period 1998‐2015, identifying its main drivers across Europe. The models were constructed based on an exhaustive collection of experimental data from scientific papers for the crops: wheat, barley, rye, oats, triticale, rice, maize, sorghum, rapeseed, sunflower, soybean, potato and sugarbeet. We discuss the assumptions on the relationship between yield and the harvest index, adopted by previous studies, to interpret the experimental data, quantify the uncertainties of these models, and establish the premises to implement them at regional scale –i.e., NUTS level 3– within the EU. To cope this, we created a consolidated sub‐national statistical data along with an algorithm able to aggregate (figures are provided at country level) and disaggregate (production at 25 km grid is provided assupplementary material) estimates. The total lignocellulosic biomass production in the EU28 over the review period, according to our models, is 419 Mt, from which wheat is the major contributor (155 Mt). Our results show that maize and rapeseed are the two crops with the highest residue yield, respectively 8.9 and 8.6 t ha‐1. The spatial analysis revealed that these three crops, which, according to our results, are feedstocks highly suitable a priori for second generation biofuels in the EU and are unevenly distributed across Europe. Weather fluctuation was identified as the major driver in residue production from cereals, while, in the case of starch crops and oilseeds – which are predominant in northern Europe – corresponded to the marked production trend likely influenced by the agricultural policies and agro‐management over the review period. Our results, among others, could help to understand and quantify the ecological boundaries of the bioeconomy from agriculture. 相似文献
113.
Giulia Schiroli Anastasia Conti Samuele Ferrari Lucrezia della Volpe Aurelien Jacob Luisa Albano Stefano Beretta Andrea Calabria Valentina Vavassori Patrizia Gasparini Eralda Salataj Delphine Ndiaye-Lobry Chiara Brombin Julie Chaumeil Eugenio Montini Ivan Merelli Pietro Genovese Luigi Naldini Raffaella Di Micco 《Cell Stem Cell》2019,24(4):551-565.e8
114.
Comes S Locascio A Silvestre F d'Ischia M Russo GL Tosti E Branno M Palumbo A 《Developmental biology》2007,306(2):772-784
Metamorphosis in the ascidian Ciona intestinalis is a very complex process which converts a swimming tadpole to an adult. The process involves reorganisation of the body plan and a remarkable regression of the tail, which is controlled by caspase-dependent apoptosis. However, the endogenous signals triggering apoptosis and metamorphosis are little explored. Herein, we report evidence that nitric oxide (NO) regulates tail regression in a dose-dependent manner, acting on caspase-dependent apoptosis. An increase or decrease of NO levels resulted in a delay or acceleration of tail resorption, without affecting subsequent juvenile development. A similar hastening effect was induced by suppression of cGMP-dependent NO signalling. Inhibition of NO production resulted in an increase in caspase-3-like activity with respect to untreated larvae. Detection of endogenously activated caspase-3 and NO revealed the existence of a spatial correlation between the diminution of the NO signal and caspase-3 activation during the last phases of tail regression. Real-time PCR during development, from early larva to early juveniles, showed that during all stages examined, NO synthase (NOS) is always more expressed than arginase and it reaches the maximum value at late larva, the stage immediately preceding tail resorption. The spatial expression pattern of NOS is very dynamic, moving rapidly along the body in very few hours, from the anterior part of the trunk to central nervous system (CNS), tail and new forming juvenile digestive organs. NO detection revealed free diffusion from the production sites to other cellular districts. Overall, the results of this study provide a new important link between NO signalling and apoptosis during metamorphosis in C. intestinalis and hint at novel roles for the NO signalling system in other developmental and metamorphosis-related events preceding and following tail resorption. 相似文献
115.
Hyperpolarization-activated cyclic nucleotide-sensitive (HCN) channels mediate the I(f) current in heart and I(h) throughout the nervous system. In spiking neurons I(h) participates primarily in different forms of rhythmic activity. Little is known, however, about its role in neurons operating with graded potentials as in the retina, where all four channel isoforms are expressed. Intriguing evidence for an involvement of I(h) in early visual processing are the side effects reported, in dim light or darkness, by cardiac patients treated with HCN inhibitors. Moreover, electroretinographic recordings indicate that these drugs affect temporal processing in the outer retina. Here we analyzed the functional role of HCN channels in rod bipolar cells (RBCs) of the mouse. Perforated-patch recordings in the dark-adapted slice found that RBCs exhibit I(h), and that this is sensitive to the specific blocker ZD7288. RBC input impedance, explored by sinusoidal frequency-modulated current stimuli (0.1-30 Hz), displays band-pass behavior in the range of I(h) activation. Theoretical modeling and pharmacological blockade demonstrate that high-pass filtering of input signals by I(h), in combination with low-pass filtering by passive properties, fully accounts for this frequency-tuning. Correcting for the depolarization introduced by shunting through the pipette-membrane seal, leads to predict that in darkness I(h) is tonically active in RBCs and quickens their responses to dim light stimuli. Immunohistochemistry targeting candidate subunit isoforms HCN1-2, in combination with markers of RBCs (PKC) and rod-RBC synaptic contacts (bassoon, mGluR6, Kv1.3), suggests that RBCs express HCN2 on the tip of their dendrites. The functional properties conferred by I(h) onto RBCs may contribute to shape the retina's light response and explain the visual side effects of HCN inhibitors. 相似文献
116.
Ammar Bader Lirio Panizzi Pier Luigi Cioni Guido Flamini 《Central European Journal of Biology》2007,2(2):206-212
The composition of the essential oils obtained from the leaves and the flowers of Achillea ligustica (Asteraceae) growing in Sicily has been studied. The main constituents of the leaves were 4-terpineol (19.3%), carvone (8.9%),
γ-terpinene (7.2%) and β-phellandrene (6.8%). 4-terpineol (12.0%), carvone (10.0%), and β-phellandrene (5.4%), along with linalool (20.4%) and cedrol (4.3%) were detected in the flower’s oil. Furthermore, the antimicrobial
activity of the essential oils and of some of the main constituents were assayed on bacteria and fungi.
In memory of Prof. Ivano Morelli (1940–2005) 相似文献
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118.
Seasonal variation of the chemical constituents of the essential oil of Santolina etrusca from Italy
The seasonal variation of the essential oil, in terms of both yield and composition, of a population of Santolina etrusca (Asteraceae) is reported in detail for different aerial parts, including sterile branches, fertile branches, and capitula. The yields generally increased from November to June, and then decreased in August and September. The main constituents of the sterile branches were 1,8-cineole and viridiflorol. The oil from fertile branches was characterized by myrcene as principal compound, whereas the essential oil obtained from the capitula contained germacrene D as the main constituent. Several compounds, as identified by GC and GC/MS, were found to prevail during the cold season. 相似文献
119.
Matthew A Schrager E Jeffrey Metter Eleanor Simonsick Alessandro Ble Stefania Bandinelli Fulvio Lauretani Luigi Ferrucci 《Journal of applied physiology》2007,102(3):919-925
The aging process is often paralleled by decreases in muscle and increases in fat mass. At the extreme these two processes lead to a condition known as "sarcopenic obesity" (Roubenoff R. Ann NY Acad Sci 904: 553-557, 2000). Research suggests that inflammatory cytokines produced by adipose tissue, especially visceral fat, accelerate muscle catabolism and thus contribute to the vicious cycle that initiates and sustains sarcopenic obesity. We tested the hypothesis that obesity and poor muscle strength, hallmarks of sarcopenic obesity, are associated with high circulating levels of proinflammatory cytokines in a random sample of the residents of two municipalities in the Chianti geographic area (Tuscany, Italy). The study sample consisted of 378 men and 493 women 65 yr and older with complete data on anthropometrics, handgrip strength, and inflammatory markers. Participants were cross-classified according to sex-specific tertiles of waist circumference and grip strength and according to a cut point for obesity of body mass index > or =30 kg/m(2). After adjusting for age, sex, education, smoking history, physical activity, and history of comorbid diseases, components of sarcopenic obesity were associated with elevated levels of IL-6, C-reactive protein, IL-1 receptor antagonist, and soluble IL-6 receptor (P < 0.05). Our findings suggest that global obesity and, to a greater extent, central obesity directly affect inflammation, which in turn negatively affects muscle strength, contributing to the development and progression of sarcopenic obesity. These results suggest that proinflammatory cytokines may be critical in both the development and progression of sarcopenic obesity. 相似文献
120.