Search for first harmonic modulation in the right ascension distribution of cosmic rays detected at the Pierre Auger Observatory

We present the results of searches for dipolar-type anisotropies in different energy ranges above 2.5 x 10(17) eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% C.L. for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations. (C) 2011 Elsevier B.V. All rights reserved.

Cognitive, Mood, and Electroencephalographic Effects of Noninvasive Cortical Stimulation With Weak Electrical Currents

Objectives: The use of noninvasive cortical electrical stimulation with weak currents has significantly increased in basic and clinical human studies. Initial, preliminary studies with this technique have shown encouraging results; however, the safety and tolerability of this method of brain stimulation have not been sufficiently explored yet. The purpose of our study was to assess the effects of direct current (DC) and alternating current (AC) stimulation at different intensities in order to measure their effects on cognition, mood, and electroencephalogram. Methods: Eighty-two healthy, right-handed subjects received active and sham stimulation in a randomized order. We conducted 164 ninety-minute sessions of electrical stimulation in 4 different protocols to assess safety of (1) anodal DC of the dorsolateral prefrontal cortex (DLPFC); (2) cathodal DC of the DLPFC; (3) intermittent anodal DC of the DLPFC and; (4) AC on the zygomatic process. We used weak currents of 1 to 2 mA (for DC experiments) or 0.1 to 0.2 mA (for AC experiment). Results: We found no significant changes in electroencephalogram, cognition, mood, and pain between groups and a low prevalence of mild adverse effects (0.11% and 0.08% in the active and sham stimulation groups, respectively), mainly, sleepiness and mild headache that were equally distributed between groups. Conclusions: Here, we show no neurophysiological or behavioral signs that transcranial DC stimulation or AC stimulation with weak currents induce deleterious changes when comparing active and sham groups. This study provides therefore additional information for researchers and ethics committees, adding important results to the safety pool of studies assessing the effects of cortical stimulation using weak electrical currents. Further studies in patients with neuropsychiatric disorders are warranted.

Tipologia e diffusione delle produzioni ceramiche in Romagna tra XIII e XV secolo

In questo lavoro si è avuta la possibilità di studiare e confrontare i reperti ceramici provenienti da tre recenti scavi condotti nella zona della Romagna dall’Università di Bologna: il monastero di San Severo a Classe (RA), il castello di Rontana (Brisighella-RA) e la pieve di S. Reparata a Terra del Sole (FC). Si tratta di scavi ancora inediti differenti tra loro sia per connotazione distrettuale di appartenenza che per tipologia insediativa La cesura cronologica che si è preso in esame va dal XIII a XV secolo. Il XIII secolo corrisponde a un periodo in cui si assiste ad una riapertura dei trasporti a lunga distanza e si diffonde la tendenza al trasferimento dei saperi tecnici da Oriente verso Occidente, fenomeno che include l’introduzione di nuove tecnologie produttive in campo ceramico come l’ingobbio e la maiolica in diversi centri urbani. Si passa poi attraverso il XIV secolo, momento in cui alcune produzioni, come quella della maiolica, raggiungono la loro massima diffusione, con una diversificazione qualitativa dei prodotti, raggiungendo anche l’ambito rurale, e si assiste alla moltiplicazione dei centri di produzione. Si arriva così al XV secolo periodo in cui iniziano ad affermarsi dei veri e propri centri produttivi “industriali”, rappresentativi anche di una specializzazione regionale dei prodotti di qualità medio-alta. La possibilità di confrontare materiali di siti così differenti tra loro ha dato modo di sottolineare analogie e differenze anche tra città e campagna, in un territorio come quello romagnolo che ancora risente del peso della lunga tradizione antiquaria che ha caratterizzato gli studi fino al secolo scorso.

Impacts of changing climate and land use on vegetation dynamics in a Mediterranean ecosystem: insights from paleoecology and dynamic modeling

Forests near the Mediterranean coast have been shaped by millennia of human disturbance. Consequently, ecological studies relying on modern observations or historical records may have difficulty assessing natural vegetation dynamics under current and future climate. We combined a sedimentary pollen record from Lago di Massacciucoli, Tuscany, Italy with simulations from the LandClim dynamic vegetation model to determine what vegetation preceded intense human disturbance, how past changes in vegetation relate to fire and browsing, and the potential of an extinct vegetation type under present climate. We simulated vegetation dynamics near Lago di Massaciucoli for the last 7,000 years using a local chironomid-inferred temperature reconstruction with combinations of three fire regimes (small infrequent, large infrequent, small frequent) and three browsing intensities (no browsing, light browsing, and moderate browsing), and compared model output to pollen data. Simulations with low disturbance support pollen-inferred evidence for a mixed forest dominated by Quercus ilex (a Mediterranean species) and Abies alba (a montane species). Whereas pollen data record the collapse of A. alba after 6000 cal yr bp, simulated populations expanded with declining summer temperatures during the late Holocene. Simulations with increased fire and browsing are consistent with evidence for expansion by deciduous species after A. alba collapsed. According to our combined paleo-environmental and modeling evidence, mixed Q. ilex and A. alba forests remain possible with current climate and limited disturbance, and provide a viable management objective for ecosystems near the Mediterranean coast and in regions that are expected to experience a mediterranean-type climate in the future.