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In this paper we discuss the ordering properties of positive radial solutions of the equation Δ p u (x) + k | x | δ u q - 1 (x) = 0 where x ∈ R n , n > p > 1 , k > 0 , δ > - p , q > p . We are interested both in regular ground states u (GS), defined and positive in the whole of R n , and in singular ground states v (SGS), defined and positive in R n \ { 0 } and such that lim | x | → 0 v (x) = + ∞ . A key role in this analysis is played by two bifurcation parameters p JL (δ) and p jl (δ) , such that p JL (δ) > p ∗ (δ) > p jl (δ) > p : p JL (δ) generalizes the classical Joseph–Lundgren exponent, and p jl (δ) its dual. We show that GS are well ordered, i.e. they cannot cross each other if and only if q ≥ p JL (δ) ; this way we extend to the p > 1 case the result proved in Miyamoto (Nonlinear Differ Equ Appl 23(2):24, 2016), Miyamoto and Takahashi (Arch Math Basel 108(1):71–83, 2017) for the p ≥ 2 case. Analogously we show that SGS are well ordered, if and only if q ≤ p jl (δ) ; this latter result seems to be known just in the classical p = 2 and δ = 0 case, and also the expression of p jl (δ) has not appeared in literature previously. [ABSTRACT FROM AUTHOR]

We critically discuss both advantages and limitations of helicopter-borne GPR surveys in rugged mountainous areas by analyzing a pseudo 3D data set acquired over the Marmolada Glacier, which constitutes the largest ice body in the Dolomites (Eastern Alps) and contains several peculiar features both in terms of the internal structures and the surrounding topography. In this paper we analyze several possible issues that can be encountered when performing airborne surveys in mountain regions, related to both the local conditions in the particular survey areas, and the general performance of the data acquisition equipment, which includes the GPR device, the GPS system, and the helicopter itself. Based on our analyses and observations, we propose a few guidelines and optimization strategies in order to address several issues, including the choice of various data acquisition parameters, interpretation problems related to curvilinear or irregular flight paths, and trace positioning errors caused by GPS malfunctioning or oscillating antennas. Such results have general validity and can be used for helicopter-borne survey planning, as well as for data analysis and interpretation. [ABSTRACT FROM AUTHOR]

We consider a modification of the model proposed by Abrams and Strogatz to describe the death of a language when it competes with a stronger one within the same community of speakers. The modification opened the possibility of coexistence of both languages under some conditions, but so far it has not been possible to write down the expression of the equilibrium points. In this paper, we nontrivially use bifurcation theory to calculate under which conditions such coexistence arises; namely, we calculate the specific ranges of the parameters that describe the modified model to have this situation, paying special attention to the cases that yield a stable cohabitation of two monolingual populations along with a bilingual one. [ABSTRACT FROM AUTHOR]

We propose an integrated methodology to image the internal structure, evaluate the volume and estimate the densities of different units within ice bodies, useful for more precise mass estimation of very small glaciers. The procedure encompasses light detection and ranging (LiDAR) and ground penetrating radar (GPR) common offset data. The case study is the Canin Eastern Glacieret (CEG), a very small and maritime glacier in the Eastern Alps, and one of the lowermost glaciers of the European Alps. We calculate both volumetric and mass variations of the analysed ice body by integrating GPR measurements with LiDAR surveys acquired in different years (2006 and 2011). Between 2006 and 2011, the area of the glacieret increased from 8,510 to 17,530 m with a gain of 9,016 m. The observed volume increase has been estimated in 96,350 m (+97 %), which corresponds to a positive mass balance of 3.89 m w.e.. This quite unusual finding in the present global warming behaviour is mainly due to the above-average winter accumulation (c) in the considered period. Moreover, the winter season 2008-2009 represented an exceptional event with a c equal to 13.38 m, the highest of the available record. Thanks to density estimation, we infer the total mass of the CEG at the time of the geophysical surveys, comparing such results with the ones obtained with available empirical equations, observing an important mass gain in the 5 years considered. [ABSTRACT FROM AUTHOR]

The use of nonsteroidal anti-inflammatory drugs (NSAIDs) can be associated with severe adverse digestive effects. In clinical settings, proton pump inhibitors have proven to be effective in preventing and healing NSAID-induced gastroduodenal lesions. The present study investigates the mechanisms of protection afforded by pantoprazole against gastric injury induced by different NSAIDs in rats. Animals were orally treated with indomethacin (100 μmol/kg), diclofenac (60 μmol/kg), piroxicam (150 μmol/kg) or ketoprofen (150 μmol/kg). Thirty minutes before NSAIDs, animals received pantoprazole 6 or 60 μmol/kg orally. Four hours after NSAIDs, the following parameters were assessed: histomorphometric evaluation of gastric mucosal damage; gastric mucosal levels of myeloperoxidase (MPO), malondialdehyde (MDA), reduced glutathione as an index of non-proteic sulfhydryl compounds (GSH), and prostaglandin E2 (PGE2); mucosal cyclooxygenase-1 and -2 (COX-1, COX-2) mRNA expression by reverse transcription-polymerase chain reaction (RT-PCR). Separate experiments were carried out to assay the effects of pantoprazole on gastric acid secretion in pylorus-ligated rats. The in vitro influence of pantoprazole (1–10 μM) on the oxidation of low density lipoproteins (LDLs) induced by copper sulphate was also examined. All NSAIDs elicited mucosal necrotic lesions associated with neutrophil infiltration and reduction of PGE2 levels. Increments of MPO and MDA contents, as well as a decrease in GSH levels, were detected in the gastric mucosa of indomethacin-, piroxicam- or ketoprofen-treated animals. Indomethacin enhanced mucosal COX-2 expression, while not affecting COX-1. At the oral dose of 6 μmol/kg pantoprazole did not affect NSAID-induced mucosal damage, whereas at 60 μmol/kg it markedly reduced injuries provoked by all test NSAIDs. Pantoprazole 60 μmol/kg also reversed the effects of NSAIDs on MPO, MDA, and GSH mucosal contents, without interfering with the decrease in PGE2 levels or indomethacin-induced COX-2 expression. However, at both doses, pantoprazole inhibited acid secretion in pylorus-ligated rats. Furthermore, pantoprazole concentration dependently reduced the in vitro oxidation of LDLs. Our results suggest that besides inhibiting acid secretion, the protection afforded by pantoprazole against NSAID-induced gastric damage depends on a reduction in mucosal oxidative injury, which may also account for an increment of sulfhydryl radical mucosal bioavailability. It is also suggested that pantoprazole does not influence the down-regulation of gastric prostaglandin production associated with NSAID treatment. [ABSTRACT FROM AUTHOR]

Meloxicam is an enolcarboxamide with preferential COX-2 inhibitory activity. In vitro studies with human tissues have confirmed the high affinity of meloxicam for COX-2, whereas COX-1 was inhibited only at the highest concentrations (ratio of 50% inhibitory concentration for COX-2 : COX-1 = 0.09 in whole blood assays). Meloxicam has a bioavailability of 89% after oral administration, is strongly bound to plasma proteins, and its half-life is 20-24 hours. It readily penetrates into synovial fluid, reaching 45-57% of plasma concentrations. Meloxicam pharmacokinetics are not significantly altered in elderly patients or in those with mild renal/hepatic impairment. The efficacy and tolerability of meloxicam in the treatment of pain and inflammation associated with rheumatic and musculoskeletal disorders has been evaluated in numerous studies comparing meloxicam 7.5-15 mg/day (up to 22.5 mg/day in ankylosing spondylitis), administered for 2 weeks to 12 months, with placebo or other nonsteroidal anti-inflammatory drugs (NSAIDs). Overall, the efficacy of meloxicam was significantly superior to that of placebo and similar to that of other NSAIDs, whereas the incidence of adverse events (especially gastrointestinal) was lower than with other NSAIDs. Intramuscular meloxicam provided faster pain relief than the oral drug in patients with rheumatoid arthritis. Meloxicam also appears to be effective in the prevention of postoperative pain, as shown in patients undergoing abdominal hysterectomy or inguinal hernia repair. Meloxicam may also have a cardioprotective role: in patients with acute coronary syndrome without ST-segment elevation, a lower incidence of cardiovascular events was observed in those who received meloxicam plus aspirin and heparin versus aspirin and heparin alone, both during coronary care stay and at 90-day follow-up. Meloxicam has demonstrated a favourable tolerability profile in large-scale comparative trials, where its gastrointestinal tolerability was superior to that of nonselective NSAIDs. In particular, meloxicam 7.5 mg/day was associated with a lower incidence of gastrointestinal adverse events compared with diclofenac (13% vs 19%; p < 0.001) or piroxicam (10.3% vs 15.4%; p < 0.001). This was confirmed by a prescription-event monitoring study that found a relatively low incidence of dyspepsia, upper gastrointestinal haemorrhage and peptic ulcer (28.3, 0.4 and 0.3 per 1000 patient-months, respectively) among first-time users of meloxicam. In conclusion, meloxicam is at least as effective as nonselective NSAIDs in the treatment of rheumatic disease or postoperative pain, but has a more favourable gastrointestinal tolerability profile. Further investigations into the potential role of meloxicam as a cardioprotective agent are warranted. [ABSTRACT FROM AUTHOR]

The protective effects of the proton pump inhibitor lansoprazole on gastric mucosal damage induced by ethanol-HCl or hemorrhagic shock were investigated in the present study. The morphometric analysis of gastric histological sections revealed that lansoprazole dose-dependently reduced mucosal injury evoked by ethanol-HCl (ED50 = 24.3 micromol/kg) or hemorrhagic shock (ED50 = 38.9 micromol/kg), these effects being associated with marked increments of Alcian blue recovery from gastric bound mucus (ED50 = 31.4 micromol/kg and 27.6 micromol/kg, respectively). In addition, lansoprazole inhibited gastric acid secretion from pylorus-ligated rats (ED50 = 9.8 micromol/kg). Further experiments, performed on rats with ethanol-HCl-induced gastric injury, indicated that the protective effects of lansoprazole were not modified by L-365,260, suramin, N(G)-nitro-L-arginine, or systemic ablation of capsaicin-sensitive sensory nerves, whereas they were partly blocked by indomethacin and fully prevented by N-ethyl-maleimide. In addition, lansoprazole did not modify somatostatin concentrations in gastric mucosa. The present results provide evidence that lansoprazole prevents the necrotic damage of gastric mucosa induced by ethanol-HCl or hemorrhagic shock. According to the rank order of ED50 values, these effects appear to depend mainly on the enhancement of the gastric mucus barrier rather than on the reduction of acid secretion. It is also proposed that an increased production of prostaglandins, as well as an increased availability of sulfhydryl compounds at level of gastric mucosa may account for the gastroprotective effects of lansoprazole. [ABSTRACT FROM AUTHOR]

Suramin is currently used in clinical practice as antineoplastic agent because of its complex interaction with the biological activity of various growth factors involved in tumor progression. The influence exerted by suramin on gastric injury induced in rats by intraluminal injection of absolute ethanol was investigated in the present study. The morphometric analysis of gastric histological sections revealed that suramin, 18 mg/kg, administered intraperitoneally for 14 days every other day, caused a marked enhancement of ethanol-induced mucosal damage. This effect was more pronounced 1-8 hr following ethanol administration, and it was still significant after 48 hr. In suramin-treated animals the evaluation of Alcian blue recovery from gastric-bound mucus showed that the levels of adherent mucus were significantly lower than those detected in untreated rats. In addition, pretreatment with suramin did not modify basal acid secretion, but caused potentiation of acid output stimulated by pylorus ligation or electrical vagal stimulation. Overall, the present results indicate that suramin exerts a negative influence on both gastric protective and repairing mechanisms. Due to the peculiar pharmacodynamic profile of suramin, it is suggested that interference with endogenous growth factors, endowed with physiological protective activity on gastric mucosa, might account for the damage-enhancing action of this drug. [ABSTRACT FROM AUTHOR]