43 research outputs found
The role of ocelli in cockroach optomotor performance
Insect ocelli are relatively simple eyes that have been assigned various functions not related to pictorial vision. In some
species they function as sensors of ambient light intensity, from which information is relayed to various parts of the nervous
system, e.g., for the control of circadian rhythms. In this work we have investigated the possibility that the ocellar light
stimulation changes the properties of the optomotor performance of the cockroach Periplaneta americana. We used a virtual
reality environment where a panoramic moving image is presented to the cockroach while its movements are recorded with
a trackball. Previously we have shown that the optomotor reaction of the cockroach persists down to the intensity of moonless
night sky, equivalent to less than 0.1 photons/s being absorbed by each compound eye photoreceptor. By occluding the
compound eyes, the ocelli, or both, we show that the ocellar stimulation can change the intensity dependence of the optomotor
reaction, indicating involvement of the ocellar visual system in the information processing of movement. We also measured
the cuticular transmission, which, although relatively large, is unlikely to contribute profoundly to ocellar function, but may
be significant in determining the mean activity level of completely blinded cockroaches
Measurement of J/ψ -pair production in pp collisions at √s = 13 TeV and study of gluon transverse-momentum dependent PDFs
The production cross-section of J/ψ pairs in proton-proton collisions at a centre-of-mass energy of √s = 13 TeV is measured using a data sample corresponding to an integrated luminosity of 4.2 fb−1 collected by the LHCb experiment. The measurement is performed with both J/ψ mesons in the transverse momentum range 0 < pT< 14 GeV/c and rapidity range 2.0 < y < 4.5. The cross-section of this process is measured to be 16.36 ± 0.28 (stat) ± 0.88 (syst) nb. The contributions from single-parton scattering and double-parton scattering are separated based on the dependence of the cross-section on the absolute rapidity difference ∆y between the two J/ψ mesons. The effective cross-section of double-parton scattering is measured to be σeff = 13.1 ± 1.8 (stat) ± 2.3 (syst) mb. The distribution of the azimuthal angle ϕCS of one of the J/ψ mesons in the Collins-Soper frame and the pT-spectrum of the J/ψ pairs are also measured for the study of the gluon transverse-momentum dependent distributions inside protons. The extracted values of ⟨cos 2ϕCS⟩ and ⟨cos 4ϕCS⟩ are consistent with zero, but the presence of azimuthal asymmetry at a few percent level is allowed
Effects of recombinant human granulocyte-macrophage colony-stimulating factor on intracellular pH in mature granulocytes
Soil loss, productivity and cropland values GIS-based analysis and trends in the Basilicata region (Southern Italy) from 1980 to 2013
This paper concerns the trends assessment of the productivity values and croplands values of specific crops (cereals (arable cereals land), vineyards, olive-growing lands) in the Basilicata region at regional scale, from 1980 to 2013, in relation to the soil loss evaluated through the USPED method. The comparative analysis shows the interrelations between the soil loss by erosion and the economic value deriving from the erosive phenomenon affecting the croplands considered
Thermal, rheological and barrier properties of waterborne acrylic nanocomposite coatings based on boehmite or organo-modified montmorillonite
An organo-modified montmorillonite (Cloisite®30B) or an unmodified boehmite (Disperal®40) have been added to two acrylic latex dispersions (one of them UV-curable) for obtaining nanocomposite coatings. X-ray diffraction and transmission electron microscopy show a high degree of exfoliation in the nanocoatings based on montmorillonite, together with the deagglomeration of the micrometer sized boehmite powder and the presence of single boehmite crystallites within the polymer matrix. Such morphologies are found to enhance the thermal and thermo-oxidative stability of the latexes and to significantly decrease their oxygen permeability, as wel
Soil Ecosystem Services and Sediment Production: The Basilicata Region Case Study
The conservation of soil and multiple ecosystem services it provides, is crucial for human well-being, for pursuing many of the Sustainable Development Goals and for addressing some of the most important challenges of our society. However several factors contribute to soil degradation, including climatic characteristics, lithological and morphological features and transformation processes. Only the last ones can be governed and that is the reason why spatial planning needs tools and analyses to interpret the role of land use changes in complex dynamics such as the erosive phenomena. This work presents the results obtained from the implementation of the InVEST SDR module on the territory of Basilicata Region and considering the evolution occurred between 1990 and 2018. Our outcomes show an intensification of erosion phenomena mainly along the Apennine chain and the coastal area of the Tyrrhenian Sea. Although this area corresponds to the higher average rainfall erosivity over the entire period, the most significant soil loss occurs in correspondence with unfavorable land use changes. The negative connotation typically associated with deforestation, conversion of agricultural soils to arable lands and thinning or total loss of vegetation becomes a measurable quantity, at least from one of several points of view