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ABSTRACTIn this paper, we present the results of the accelerator mass spectrometry radiocarbon (AMS14C) dating campaign performed on samples selected from different levels in Grotta Romanelli (Castro, Italy). Grotta Romanelli is one of the key sites for the chronology of Middle Pleistocene–Holocene in Mediterranean region. After the first excavation campaigns carried out in the first decades of the 1900s, the cave has been systematically re-excavated only since 2015. During the last excavation campaigns different faunal remains were selected and submitted for 14C dating in order to confirm the chronology of the cave with a higher resolution. Isotopic ratio mass spectrometry (IRMS) measurements were also carried out on faunal remains.

AbstractA new sputtering ion source has been installed at CEDAD (Centre for Dating and Diagnostics) at the University of Salento in Lecce, Italy. The installation of the new ion source, capable of accepting both solid and gas samples, required significant modifications of the existing low energy injector of the accelerator mass spectrometry (AMS) system. The new ion source is connected, through an in-house designed gas handling interface, to an elemental analyzer which combusts the samples to carbon dioxide and splits the gas into an IRMS system and also to the gas feed line of the ion source. This arrangement allows the simultaneous measurement of C, N content (in the EA), carbon and nitrogen stable isotopic ratios by IRMS and radiocarbon (14C) by AMS on samples with masses in the microgram range. The results of different tests performed to find optimal operational conditions and to improve the system performances are presented. The performances of the system as a function of the diameter of the glass capillary used to feed the source and the pressure of the gas mixture in the syringe are also presented. The achievable precision and blank levels are discussed together with the results obtained in environmental studies.

The Multiplicative MIDAS Realized DCC (MMReDCC) model simultaneously accounts for short and long term dynamics in the conditional (co)volatilities of asset returns, in line with the empirical evidence suggesting that their level is changing over time as a function of economic conditions. Herein the applicability of the model is improved along two directions. First, by proposing an algorithm that relies on the maximization of an iteratively re-computed moment-based profile likelihood function and keeps estimation feasible in large dimensions by mitigating the incidental parameter problem. Second, by illustrating a conditional bootstrap procedure to generate multi-step ahead predictions from the model. In an empirical application on a dataset of forty-six equities, the MMReDCC model is found to statistically outperform the selected benchmarks in terms of in-sample fit as well as in terms of out-of-sample covariance predictions. The latter are mostly significant in periods of high market volatility.

We propose a scalar variation of the multivariate HEAVY model of Noureldin et al. (2012) featuring a time-varying long run (co)volatility component coupled with DCC dynamics. The new model outperforms the original HEAVY model by delivering more accurate multi-step-ahead predictions. [ABSTRACT FROM AUTHOR]

ABSTRACTExperimental animal models of bacterial meningitis are useful to study the host-pathogen interactions occurring at the cerebral level and to analyze the pathogenetic mechanisms behind this life-threatening disease. In this study, we have developed a mouse model of meningococcal meningitis based on the intracisternal inoculation of bacteria. Experiments were performed with mouse-passaged serogroup C Neisseria meningitidis.Survival and clinical parameters of infected mice and microbiological and histological analysis of the brain demonstrated the establishment of meningitis with features comparable to those of the disease in humans. When using low bacterial inocula, meningococcal replication in the brain was very efficient, with a 1,000-fold increase of viable counts in 18 h. Meningococci were also found in the blood, spleens, and livers of infected mice, and bacterial loads in different organs were dependent on the infectious dose. As glutamate uptake from the host has been implicated in meningococcal virulence, mice were infected intracisternally with an isogenic strain deficient in the ABC-type l-glutamate transporter GltT. Noticeably, the mutant was attenuated in virulence in mixed infections, indicating that wild-type bacteria outcompeted the GltT-deficient meningococci. The data show that the GltT transporter plays a role in meningitis and concomitant systemic infection, suggesting that meningococci may use l-glutamate as a nutrient source and as a precursor to synthesize the antioxidant glutathione.

The aim of this study was to assess the efficacy and tolerability of single doses of nimesulide beta cyclodextrin compared with nimesulide in patients with dental pain following surgical procedures. This was a randomised, double‐blind, between‐patient, multicentre study involving 148 outpatients suffering from moderate to severe pain, who received single doses of either 400 mg nimesulide beta cyclodextrin or 100 mg nimesulide. The principal criterion for efficacy was pain intensity assessed on a visual analogue scale (VAS) 15 minutes after drug intake. Pain intensity was further evaluated 30, 45, 90, 120, 180, 240 and 360 minutes after dosing. Pain relief was evaluated at the same time points by means of a categorical scale. The time point of first pain relief, the use of rescue medication and the global evaluation of efficacy were also recorded. The reduction in pain intensity was significantly more pronounced in the nimesulide beta cyclodextrin group at 15, 30, 45 and 60 minutes (p<0.01). Pain relief was significantly greater (p<0.05) and more rapid with nimesulide beta cyclodextrin. In the patient overall assessment of efficacy, nimesulide beta cyclodextrin and nimesulide were rated excellent or good by 95% and 92% respectively; only one patient in the nimesulide beta cyclodextrin group needed rescue medication. Both study drugs were effective and well tolerated in the treatment of acute dental pain, with nimesulide beta cyclodextrin showing a faster onset of analgesic action.