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We derive analytic approximations to the solutions of the Lane–Emden equation, a basic equation in Astrophysics that describes the Newtonian equilibrium structure of a self-gravitating polytropic fluid sphere. After recalling some basic results, we focus on the construction of rational approximations, discussing the limitations of previous attempts, and providing new accurate approximate solutions. [ABSTRACT FROM AUTHOR]

Medication overuse headache (MOH) is a challenging, debilitating disorder that develops from the frequent use of medications taken for the treatment of migraine headache pain. MOH affects an estimated 3–5% of the general population. The mechanisms underlying the development of MOH remain unknown. Opiates are one of the major classes of medications used for the treatment of migraine at least in some countries, including the USA. Although the effects of repeated opiate use for headache are unknown, it is possible that opiate use may contribute to increased frequency and occurrence of such headaches. Recent preclinical studies exploring the neuroadaptive changes following sustained exposure to morphine may give some insights into possible causes of MOH. Peripherally, these changes include increased expression of calcitonin gene-related peptide (CGRP) in trigeminal primary afferent neurons. Centrally, they include increased excitatory neurotransmission at the level of the dorsal horn and nucleus caudalis. Critically, these neuroadaptive changes persist for long periods of time and the evoked release of CGRP is enhanced following morphine pretreatment. Stimuli known to elicit migraine, such as nitric oxide donors or stress, produce hyperalgesia in morphine- but not in saline-pretreated rats even long after the discontinuation of the opiate. CGRP plays a prominent role in initiating vasodilation of the intracranial blood vessels and subsequent headache. Furthermore, studies have demonstrated increased excitability of the nociceptive pathway in migraine sufferers, and CGRP receptor antagonists have been shown to be efficacious in migraine pain. Thus, such persistent neuroadaptive changes may be relevant to the processes that promote MOH. [ABSTRACT FROM AUTHOR]

The variance of soil moisture, vegetation and evapotranspiration over land has been recognized to be strongly connected to the variance of precipitation. However, the feedbacks and couplings between these variables are still not well understood and quantified. Furthermore, soil moisture and vegetation processes are associated to a memory and therefore they may have important implications for predictability. In this study we apply a generalized linear method, specifically designed to assess the reciprocal forcing between connected fields, to the latest available observational datasets of global precipitation, evapotranspiration, vegetation and soil moisture content. For the first time a long global observational dataset is used to investigate the spatial and temporal land variability and to characterize the relationships and feedbacks between land and precipitation. The variables considered show a significant coupling among each other. The analysis of the response of precipitation to soil moisture evidences a robust coupling between these two variables. In particular, the first two modes of variability of the precipitation forced by soil moisture appear to have a strong link with volcanic eruptions and ENSO cycles, respectively, and these links are modulated by the effects of evapotranspiration and vegetation. It is suggested that vegetation state and soil moisture provide a biophysical memory of ENSO and major volcanic eruptions, revealed through delayed feedbacks on rainfall patterns. The third mode of variability reveals a trend very similar to the trend of the inter-hemispheric contrast in SST and appears to be connected to greening/browning trends of vegetation over the last three decades. [ABSTRACT FROM AUTHOR]

The use of the extra virgin olive oil as covering in food preserves presents some problems and still today object of study. With this research it was investigate the changes of some analytical parameters that occur during the storage in the olive oils used as covering in eggplant preserves. It was ascertained that in the oils in presence of the eggplants a drastic decrease of the total phenols was verified immediately after the thermal treatment affecting the oxidative processes. Besides it was observed that in all the oils stored under light the values of the K270. ∆K, the total chlorophylls and the 1,2-DG36/1,3-DG36 ratio were significantly changed. [ABSTRACT FROM AUTHOR]

Climate simulations consistently show an increase in European near-surface air temperature by the late 21st century, although projections for near-surface wind speeds and irradiance differ between models, and are accompanied by large natural variability. These factors make it difficult to estimate the effects of physical climate change on power system planning. Here, the impact of climate change on future European power systems is estimated. We show for the first time how a set of divergent future power system scenarios lead to marked differences in Europe's total energy balance (demand-net-renewable supply) by 2050, which dominate over the uncertainty associated with climate change (∼50% and ∼5% respectively). However, within any given power system scenario, national power systems may be subject to considerable impacts from climate change, particularly for seasonal differences between renewable resources (e.g., wind power may be impacted by ∼20% or more). There is little agreement between climate models in terms of the spatio-temporal pattern of these impacts, and even in the direction of change for wind and solar. More thorough consideration of climate uncertainty is therefore needed, as it is likely to be of great importance for robust future power system planning and design. • Future climate affects European power systems simulated with EURO-CORDEX models. • Significant climate uncertainty in key power system properties (demand, renewables). • Climate uncertainty exacerbated in renewable-intensive power system scenarios. • Spatio-temporal and multi-model aggregation masks complex patterns of change. • Better understanding of climate uncertainty in power system design is needed. [ABSTRACT FROM AUTHOR]

Achieving carbon-neutrality is increasing the demand of renewable electricity which is raising the competition for land and associated acquisition costs. Installation of floating photovoltaic (FPV) on existing hydropower reservoirs offers one solution to limited land availability while providing solar electricity, leveraging water bodies, and reducing water evaporation losses. This work assesses the potential electricity output of FPVs at regional and national levels on 337 hydropower reservoirs in the EU27 considering four scenarios and two types of floaters. Evaporation, water losses and water savings due to FPVs installation are also estimated using climatic parameters for the year 2018. The reservoirs' total water losses are estimated at 9380 mcm. The installation of FPVs of equal installed capacity as the hydropower plants, has the potential to generate 42.31 TWh covering 2.3% of the total reservoir area. In this case, up to 557 mcm could be saved by installing FPV. The FPVs' multiple benefits and the potential offered by existing hydropower reservoirs are compatible with the EU's goals for net zero emissions and more autonomy from imported fossil fuels and energy transformation. • Potential FPV elect. generation corresponds to 20%–87%, of the total EU solar PV. • Using only 2.3% of total hydropower reservoir areas could produce 42.3 TWh/yr. • Using <15% of EU's reservoir area, FPV output ∼50% of the hydropower generation. • A 10% reservoir area coverage with FPV results in 1717.8 mcm annual water savings. [ABSTRACT FROM AUTHOR]

BACKGROUND AND PURPOSE The amphibian peptide Bv8 induces potent nociceptive sensitization in rodents. Its mammalian homologue, prokineticin 2 (PROK2), is strongly up-regulated in inflamed tissues and is a major determinant in triggering inflammatory pain. Bv8 and PROK2 activate two closely related GPCRs, PK1 and PK2, in a relatively non-selective fashion. To characterize better the roles of the two receptors in hyperalgesia and to obtain ligands whose binding affinity and efficacy differed for the two receptors, we modified the Bv8 molecule in regions essential for receptor recognition and activation. EXPERIMENTAL APPROACH We modified the Bv8 molecule by substituting Trp in position 24 with Ala (A-24) and compared it with Bv8 for binding and activating PK1 and PK2 receptors in cell preparations and in affecting nociceptive thresholds in rodents. KEY RESULTS A-24 preferentially bound to PK2 receptors and activated them with a lower potency (5-fold) than Bv8. When systemically injected, A-24 induced Bv8-like hyperalgesia in rats and in mice, at doses 100 times higher than Bv8. Locally and systemically injected at inactive doses, A-24 antagonized Bv8-induced hyperalgesia. In rat and mouse models of inflammatory and post-surgical pain, A-24 showed potent and long-lasting anti-hyperalgesic activity. Unlike Bv8, A-24 increased β-endorphin levels in mouse brain. CONCLUSIONS AND IMPLICATIONS A-24 induced its anti-hyperalgesic effect in rodents by directly blocking nociceptor PK1 receptors and by activating the central opioid system and the descending pain control pathway through brain PK2 receptors. [ABSTRACT FROM AUTHOR]

Aims: To isolate and characterize spore-former bacteria able to colonize the human gastrointestinal tract (GIT). Methods and Results: A total of 25 spore-formers was isolated from faeces and ileal biopsies of healthy human volunteers and identified at the species level. Physiological analysis was performed to evaluate the ability of the various isolates to form biofilms, to swarm, to produce surfactants and molecules that have antimicrobial activity against selected pathogens. To assess the potential probiotic activity of the isolates, we tested the resistance of cells and spores to simulated gastric conditions, the ability to grow and sporulate in anaerobic conditions and the presence of toxin-encoding genes in their genome. Conclusions: Spore-formers belonging to various bacterial species have been isolated from the gut of healthy human volunteers. These strains appear to be well adapted to the intestinal environment and we propose them as potential probiotic strains for human use and as oral vaccine vehicles. Significance and Impact of the Study: To our knowledge this is the first detailed characterization of spore-forming Bacilli from the human GIT. Our data suggest that the isolated species do not transit, but rather colonize this specific habitat and propose them as probiotic strains for human use. [ABSTRACT FROM AUTHOR]

The thyroid-stimulating hormone/thyrotropin (TSH) is the most relevant hormone in the control of thyroid gland physiology in adulthood. TSH effects on the thyroid gland are mediated by the interaction with a specific TSH receptor (TSHR). We studied the role of TSH/TSHR signaling on gland morphogenesis and differentiation in the mouse embryo using mouse lines deprived either of TSH (pit[sup dW]/pit[sup dw]) or of a functional TSHR (tshr[sup hyt]/tshr[sup hyt] and TSHRknockout lines). The results reported here show that in the absence of either TSH or a functional TSHR, the thyroid gland develops to a normal size, whereas the expression of thyroperoxidase and the sodium/iodide symporter are reduced greatly. Conversely, no relevant changes are detected in the amounts of thyroglobulin and the thyroid-enriched transcription factors TTF-1, TTF-2, and Pax8. These data suggest that the major role of the TSH/TSHR pathway is in controlling genes involved in iodide metabolism such as sodium/iodide symporter and thyroperoxidase. Furthermore, our data indicate that in embryonic life TSH does not play an equivalent role in controlling gland growth as in the adult thyroid. [ABSTRACT FROM AUTHOR]