Mechanical properties of three-phase polyamide 6 nanocomposites

This work focus on the mechanical properties of three-phase nanocomposites using multiscale reinforcements. The influence of the nano-fillers content, as well as the temperature were studied. Polyamide-6 reinforced with short glass fibre 30 wt.% and with an addition of nanoclay (montmorillonite) and/or nanosilica (SiO2) were tested in order to characterise their tensile properties at room temperature and at 65oC just above the polyamide 6 glass transition temperature. SEM analysis were conducted on the fracture surface of the tensile bars. SEM investigations showed the importance of the interaction matrix/filler for the material behaviour. Our study also shows that the increase of OMMT percentage in polyamide-6/glass fibre composite made the material more brittle and had a negative effect on the tensile properties. Further, for the silica-based nanocomposites, an optimum was found for a nanofillers content of 1wt.%

The European VLF/LF radio network: current status

For several years researches about correlation between seismicity and disturbances in radio broadcasting are being carried out: in particular, the Japanese Pacific VLF radio network and the European VLF–LF radio network have been developed during the last years. The European network has been developed starting from two LF receivers located in central Italy in 1996. Up to now, 11 receivers of a new type, able to sample the VLF and LF intensity of ten radio signals, are being into operation in different European countries. The daily updating of data is effective and the data bank is located at the Department of Physics of the University of Bari (Italy) which is the central node of the network. In order to discover anomalies, the software able to carry out automatically a daily data analysis by the Wavelet spectra method has been planned and realized. At the moment, the software operates on four signals (two LF and two VLF) collected by one of the receiver located in Italy. If the anomaly is particularly strong a warning system gives an advise on the work station into operation in the central node of the Network. In any case, before assuming an anomaly as a seismic anomaly, geomagnetic and meteorological data must be checked as well as any possible instrumental malfunction. At present these controls are carried out only discontinuously by the researchers of the Bari Team

The Effect of Error-Correction on Testing the Rational-Expectations Neutrality Hypothesis

By adopting a VAR framework in first differences, recent literature has confirmed previous results in testing the macro rational-expectations hypotheses of rationality and neutrality: rationality is corroborated, neutrality is rejected. However, this paper shows that, by correctly incorporating a long-run cointegrating relationship between money, output and interest rate in the form of an error-correction term, the test results are reversed, in that neutrality is no longer rejected.rationality, neutrality, error-correction

Wavelet analysis of the LF radio signals collected by the European VLF/LF network from July 2009 to April 2011

In 2008, a radio receiver that works in very low frequency (VLF; 20-60 kHz) and LF (150-300 kHz) bands was developed by an Italian factory. The receiver can monitor 10 frequencies distributed in these bands, with the measurement for each of them of the electric field intensity. Since 2009, to date, six of these radio receivers have been installed throughout Europe to establish a ‘European VLF/LF Network’. At present, two of these are into operation in Italy, and the remaining four are located in Greece, Turkey, Portugal and Romania. For the present study, the LF radio data collected over about two years were analysed. At first, the day-time data and the night-time data were separated for each radio signal. Taking into account that the LF signals are characterized by ground-wave and sky-wave propagation modes, the day-time data are related to the ground wave and the night-time data to the sky wave. In this framework, the effects of solar activity and storm activity were defined in the different trends. Then, the earthquakes with M ≥5.0 that occurred over the same period were selected, as those located in a 300-km radius around each receiver/transmitter and within the 5th Fresnel zone related to each transmitter-receiver path. Where possible, the wavelet analysis was applied on the time series of the radio signal intensity, and some anomalies related to previous earthquakes were revealed. Except for some doubt in one case, success appears to have been obtained in all of the cases related to the 300 km circles in for the ground waves and the sky waves. For the Fresnel cases, success in two cases and one failure were seen in analysing the sky waves. The failure occurred in August/September, and might be related to the disturbed conditions of the ionosphere in summer

Treatment of Porphyromonas gulae infection and downstream pathology in the aged dog by lysine-gingipain inhibitor COR388.

COR388, a small-molecule lysine-gingipain inhibitor, is currently being investigated in a Phase 2/3 clinical trial for Alzheimer's disease (AD) with exploratory endpoints in periodontal disease. Gingipains are produced by two species of bacteria, Porphyromonas gingivalis and Porphyromonas gulae, typically associated with periodontal disease and systemic infections in humans and dogs, respectively. P. gulae infection in dogs is associated with periodontal disease, which provides a physiologically relevant model to investigate the pharmacology of COR388. In the current study, aged dogs with a natural oral infection of P. gulae and periodontal disease were treated with COR388 by oral administration for up to 90 days to assess lysine-gingipain target engagement and reduction of bacterial load and downstream pathology. In a 28-day dose-response study, COR388 inhibited the lysine-gingipain target and reduced P. gulae load in saliva, buccal cells, and gingival crevicular fluid. The lowest effective dose was continued for 90 days and was efficacious in continuous reduction of bacterial load and downstream periodontal disease pathology. In a separate histology study, dog brain tissue showed evidence of P. gulae DNA and neuronal lysine-gingipain, demonstrating that P. gulae infection is systemic and spreads beyond its oral reservoir, similar to recent observations of P. gingivalis in humans. Together, the pharmacokinetics and pharmacodynamics of COR388 lysine-gingipain inhibition, along with reduction of bacterial load and periodontal disease in naturally occurring P. gulae infection in the dog, support the use of COR388 in targeting lysine-gingipain and eliminating P. gingivalis infection in humans

Anomalies Observed in VLF and LF Radio Signals on the Occasion of the Western Turkey Earthquake (Mw = 5.7) on May 19, 2011

VLF radio signals lie in the 10 - 60 kHz frequency band. These radio signals are used for worldwide navigation support, time signals and for military purposes. They are propagated in the earth-ionosphere wave-guide mode along great circle propagation paths. So, their propaga-tion is strongly affected by the ionosphere conditions. LF signals lie in 150 - 300 kHz frequency band. They are used for long way broadcasting by the few (this type of broadcasting is going into disuse) transmitters located in the world. These radio signals are characterized by the ground wave and the sky wave propagation modes [1]. The first generates a stable signal that propagates in the channel Earth-troposphere and is affected by the surface ground and troposphere condition. The second instead gives rise to a signal which varies greatly between day and night, and between summer and winter, and which propagates using the lower ionosphere as a reflector; its propagation is mainly affected by the ionosphere condi-tion, particularly in the zone located in the middle of the transmitter-receiver path. The propagation of the VLF/LF radio signals is affected by different factors such as the meteorological condition, the solar bursts and the geo-magnetic activity. At the same time, variations of some parameters in the ground, in the atmosphere and in the ionosphere occurring during the preparatory phase of earthquakes can produce disturbances in the above men-tioned signals. As already reported by many previous studies [2-18] the disturbances are classified as anoma-lies and different methods of analysis as the residual dA/ dP [15], the terminator time TT [9], the Wavelet spectra and the Principal Component Analysis have been used [6,7]. Here the analysis carried out on LF and VLF radio signals using three different methods on the occasion of a strong earthquake occurred recently in Turkey is pre-sented

Analisi della suscettibilità da frana a scala di bacino (Bacino del Fiume Arno, Toscana-Umbria, Italia)

In questa nota vengono presentati i metodi applicati e i risultati ottenuti in una recente analisi della pericolosità da frana, condotta sul territorio del Bacino del Fiume Arno nell’ambito di una convenzione tra l’Autorità di Bacino e il Dipartimento di Scienze della Terra dell’Università di Firenze (2002-2005). Tutti i dati acquisiti, confluiti in una banca dati GIS, sono stati sintetizzati in carte tematiche e in una carta inventario delle frane. La sovrapposizione dei fattori predisponenti selezionati (pendenza, litologia, uso del suolo, curvatura di profilo e area drenata) ha permesso di definire le unità elementari per il trattamento statistico (Unità Territoriali Omogenee: UTO). La valutazione della pericolosità è stata estesa alle aree prive di movimenti franosi utilizzando metodi statistici multivariati implementati in Reti Neurali Artificiali. L’area di studio è stata suddivisa in cinque Macroaree morfologicamente e geologicamente omogenee: per ogni Macroarea, i predittori neurali sono stati addestrati su un opportuno sottoinsieme di dati, applicando poi i migliori all’intero data-set al fine di generare valori previsti dell’indice di suscettibilità per ogni UTO. Infine, i valori di uscita sono stati riclassificati in differenti livelli di pericolosità in base a criteri di soglia e validati per confronto con l’inventario. Una percentuale di area in frana compresa tra l’81 e il 96% risulta correttamente classificata dalla previsione nelle varie Macroare

Present status and preliminary results of the VLF/LF radio recording European network installed in 2009.

In January 2009 a European network of receivers able to measure the electric field intensity from various VLF/LF broadcasting stations located throughout Europe, was installed. Five new receivers constructed by an Italian enterprise have been delivered to Greece, Romania, Turkey and to the Italian team. The motivation of this effort is to study the possible connections between the preparatory phase of earthquakes and perturbations in the transmitted radio signals. The receivers can be reached via ftp and gsm mobile connection, thus allowing a real time data collection. We present here the status of the network and the various testing steps performed in order to achieve a correct set up. We show how antennas variations, receivers locations and changes of selected frequencies affect the performances of the whole network. After this necessary testing period, several LF/VLF radio signals are now simultaneously and continuously being sampled by the five receivers. As a preliminary result we inspect also specific cases in which an anomaly in the radio signals is clearly related to the transmitter or to the receiver (e.g. meteorological conditions around the sampling site). At a basic level, the analysis adopted consists in a simple statistical evaluation of the signals by comparing the instantaneous values to the trend of the signal