The vertical and horizontal distribution of Mesocriconema xenoplax (Raski, 1952) in Trentino vineyards (Northern Italy)

Spatial distribution of Mesocriconema xenoplax (Raski, 1952) was investigated in vineyards in the Trentino region (Northern Italy). Horizontal distribution showed characteristic aggregate pattern for nematodes, correlated to the symptomatology of the localized spots of infestations. The vertical distribution, in compact texture soils, revealed maximum population levels of the nematode in the top layers depending on the root occurrence that, in such conditions, is lower at the deeper levels. Higher nematode number was found at greater depths in loose soils, where roots easier penetrate. The knowledge gained from the spatial distribution of this species is fundamental to investigate the effectiveness of different sampling patterns in order to improve efficacy of control strategies

MANAGEMENT OF THE ROOT-KNOT NEMATODE MELOIDOGYNE INCOGNITAON TOMATO WITH DIFFERENT COMBINATIONS OF NEMATICIDESAND A RESISTANT ROOTSTOCK: PRELIMINARY DATA

In south Italy, tomato growers commonly face severe root-knot nematode infestations. Alternative methods ofcontrol are required because of the high toxicity of current pesticides. Therefore, the potential of an integrated pestmanagement strategy for the control of root-knot nematodes on tomato in greenhouse was investigated. The nematodesusceptible tomato cv. Ikram, non-grafted or grafted onto the tomato rootstock cv. Armstrong, with intermediate resistanceto the nematode, in combination with soil applications of the nematicides fosthiazate, oxamyl, and abamectin were tested.The resistant rootstock significantly reduced nematode soil population levels and root galling index until one month aftertransplanting, when soil temperature was below 28°C, but not by harvest due to increased soil temperature. Fosthiazate,abamectin and oxamyl increased tomato yield and reduced root galling caused by Meloidogyne incognita. The synergisticeffect of the rootstock resistant to root-knot nematodes and soil treatments of fosthiazate in combination with abamectin oroxamyl could successfully be employed in integrated pest management programs to control M. incognita in tomato

Middle Stone Age Ochre Processing and Behavioural Complexity in the Horn of Africa : Evidence from Porc-Epic Cave, Dire Dawa, Ethiopia

Ochre is a common feature at Middle Stone Age (MSA) sites and has often been interpreted as a proxy for the origin of modern behaviour. However, few ochre processing tools, ochre containers, and ochre-stained artefacts from MSA contexts have been studied in detail within a theoretical framework aimed at inferring the technical steps involved in the acquisition, production and use of these artefacts. Here we analyse 21 ochre processing tools, i.e. upper and lower grindstones, and two ochre-stained artefacts from the MSA layers of Porc-Epic Cave, Dire Dawa, Ethiopia, dated to ca. 40 cal kyr BP. These tools, and a large proportion of the 4213 ochre fragments found at the site, were concentrated in an area devoted to ochre processing. Lower grindstones are made of a variety of raw materials, some of which are not locally available. Traces of use indicate that different techniques were employed to process ochre. Optical microscopy, XRD, μ-Raman spectroscopy, and SEM-EDS analyses of residues preserved on worn areas of artefacts show that different types of ferruginous rocks were processed in order to produce ochre powder of different coarseness and shades. A round stone bearing no traces of having been used to process ochre is half covered with residues as if it had been dipped in a liquid ochered medium to paint the object or to use it as a stamp to apply pigment to a soft material. We argue that the ochre reduction sequences identified at Porc-Epic Cave reflect a high degree of behavioural complexity, and represent ochre use, which was probably devoted to a variety of functions

Bulk detection of time-dependent topological transitions in quenched chiral models

The topology of one-dimensional chiral systems is captured by the winding number of the Hamiltonian eigenstates. Here we show that this invariant can be read-out by measuring the mean chiral displacement of a single-particle wavefunction that is connected to a fully localized one via a unitary and translational-invariant map. Remarkably, this implies that the mean chiral displacement can detect the winding number even when the underlying Hamiltonian is quenched between different topological phases. We confirm experimentally these results in a quantum walk of structured light

A low-cost radiation detection system to monitor radioactive environments by unmanned vehicles

AbstractUnconventional scenarios with hazardous radioactive levels are expected as consequences of accidents in the industrial sector of the nuclear energy production or following intentional releases of radioactive materials for terrorist purposes (dirty bombs, indoor contaminations, etc.). Nowadays, the need to balance the high standards of safety and security through an effective detection network is a matter of paramount importance. In this work, the authors' challenge has been to design, realize and test a low-cost gamma detection and spectroscopy system which may be used in unmanned vehicles in general and/or drones with low payload capabilities. The designed platform may be used to carry out mapping or localization operations in order to reduce the risk factor for first responders or for the population affected by radiological and nuclear events. In this paper, the design process of a gamma ray detection and spectroscopy system based on affordable and commercially available technologies is presented along with the results of our ongoing characterization of the prototype

Critical evaluation of in situ analyses for the characterisation of red pigments in rock paintings: A case study from El Castillo, Spain

Paint technology, namely paint preparation and application procedures, is an important aspect of painting traditions. With the expansion of archaeometric studies and in situ non-destructive analytical methods, a renewal of technological studies is being observed in rock art. In situ analyses have several limitations that are widely discussed in the literature, however. It is not yet clear whether they provide accurate information on paint technology, except under certain conditions. Here, we evaluated digital microscopic and pXRF in situ analyses for the characterisation of a large set of red and yellow paintings from the El Castillo cave, Cantabria, Spain. We have set experiments and used statistical methods to identify differences between paint components and determine factors impacting pXRF measurements. We found that the compositional heterogeneity of the paintings’ environment, especially variations in secondary deposits, was responsible for most of the differences observed between the pXRF signals recorded on the paintings. We concluded that the El Castillo cave environment is not suitable for non-destructive technological studies, but that more favourable contexts might exist. Following previous works and our own results, we advocate a combination of both in situ and laboratory invasive analyses for the study of paint composition and paint technology. Our research protocol, based on the comparison of rock paintings, their substrate, experimental paintings and Fe-normalisation of the signals can improve the reliability of pXRF results. We also propose to include more systematic characterisation of rock wall heterogeneity and the use of microscopic analyses in non-destructive approaches.publishedVersio

Biphoton State Reconstruction via Phase Retrieval Methods

The complete measurement of the quantum state of two correlated photons requires reconstructing the amplitude and phase of the biphoton wavefunction. We show how, by means of spatially resolved single photon detection, one can infer the spatial structure of bi-photons generated by spontaneous parametric down conversion. In particular, a spatially resolved analysis of the second-order correlations allows us to isolate the moduli of the pump and phasematching contributions to the two-photon states. When carrying this analysis on different propagation planes, the free space propagation of pump and phasematching is observed. This result allows, in principle, to gain enough information to reconstruct also the phase of pump and phasematching, and thus the full biphoton wavefunction. We show this in different examples where the pump is shaped as a superposition of orbital angular momentum modes or as a smooth amplitude with a phase structure with no singularities. The corresponding phase structure is retrieved employing maximum likelihood or genetic algorithms. These findings have potential applications in fast, efficient quantum state characterisation that does not require any control over the source

Testing the Hypothesis of Fire Use for Ecosystem Management by Neanderthal and Upper Palaeolithic Modern Human Populations

BACKGROUND: It has been proposed that a greater control and more extensive use of fire was one of the behavioral innovations that emerged in Africa among early Modern Humans, favouring their spread throughout the world and determining their eventual evolutionary success. We would expect, if extensive fire use for ecosystem management were a component of the modern human technical and cognitive package, as suggested for Australia, to find major disturbances in the natural biomass burning variability associated with the colonisation of Europe by Modern Humans. METHODOLOGY/PRINCIPAL FINDINGS: Analyses of microcharcoal preserved in two deep-sea cores located off Iberia and France were used to reconstruct changes in biomass burning between 70 and 10 kyr cal BP. Results indicate that fire regime follows the Dansgaard-Oeschger climatic variability and its impacts on fuel load. No major disturbance in natural fire regime variability is observed at the time of the arrival of Modern Humans in Europe or during the remainder of the Upper Palaeolithic (40-10 kyr cal BP). CONCLUSIONS/SIGNIFICANCE: Results indicate that either Neanderthals and Modern humans did not influence fire regime or that, if they did, their respective influence was comparable at a regional scale, and not as pronounced as that observed in the biomass burning history of Southeast Asia

Remote light source for silicon photonic transceivers in mobile fronthaul applications

The design and experimental characterisation of a depolarised light source for feeding a remote transceiver based on silicon photonics are presented. Since the transceiver only works in TE mode, the source is designed to deliver, over up to 10 km standard single-mode fibre links, a continuous-wave light with almost constant power along this polarisation direction, whatever be the random polarisation rotation because of the fibre link. The depolarised light source is realised by combining the output of two independent distributed feedback lasers, having orthogonal polarisation and controlled frequency difference. The transmission performance and stability of the remote light source are successfully tested