650 research outputs found
Smooth golden fleece and prickly golden fleece as potential new vegetables for the ready-to-eat production chain
Smooth golden fleece (Urospermum dalechampii (L.) F.W. Schmidt) and prickly golden fleece (Urospermum picroides (L.) Scop. ex F.W. Schmid) are two wild edible plants used in traditional cuisine and folk medicine. In this research, the domestication of both species was tested for the first time using a floating system and two plant densities (412 and 824 plants m−2) to evaluate yield and quality. Some quality traits were also compared in cultivated plants and wild ones gathered in grasslands. The results show that both species are suitable for cultivation, although prickly golden fleece showed highest total phenols (132 mg 100 g−1 fresh weight—f.w.) and total antioxidant activity (0.19 mg 100 g−1 f.w.). At low sowing density, smooth golden fleece showed a nitrate content of about 7200 mg kg−1 f.w., 38% higher than plants of the same species grown at high density and plants of prickly golden fleece. These results suggest that high density can be used to optimize yield in two harvests. By permitting modulation of nutrients and a product without soil residues, the floating system used in this study proved suitable for growing U. dalechhampii and U. picroides as new vegetables for the ready-to-eat production chain
Minimally invasive (flapless) crown lengthening by erbium: YAG laser in aesthetic zone
Crown lengthening is a surgical procedure aimed at exposure of a larger tooth surface by gingivectomy alone or with cortical bone remodelling for aesthetic purposes in the anterior zone of the maxilla or for reconstruction of teeth affected by subgingival caries. We report two cases of crown lengthening in the anterior maxilla for aesthetic purposes by gingival and bone re-contouring performed by erbium-doped yttrium aluminium garnet (erbium:YAG) laser. As highlighted in this report, the erbium:YAG laser-assisted crown lengthening is less invasive and also leads to faster clinical outcomes in contrast to the conventional surgical technique by scalpel incision, flap elevation and osteoplastic
A minimally invasive technique for short spiral implant insertion with contextual crestal sinus lifting in the atrophic maxilla: A preliminary report
The most recently reported techniques for the rehabilitation of the atrophic posterior maxilla are increasingly less invasive, as they are generally oriented to avoid sinus floor elevation with lateral access. The authors describe a mini-invasive surgical technique for short spiral implant insertion for the prosthetic rehabilitation of the atrophic posterior maxilla, which could be considered a combination of several previously described techniques based on the under-preparation of the implant site to improve fixture primary stability and crestal approach to the sinus floor elevation without heterologous bone graft. Eighty short spiral implants were inserted in the molar area of the maxilla in patients with 4.5–6 mm of alveolar bone, measured on pre-operative computed tomography. The surgical technique involved careful drilling for the preparation of implant sites at differentiated depths, allowing bone dislocation in the apical direction, traumatic crestal sinus membrane elevation, and insertion of an implant (with spiral morphology) longer than pre-operative measurements. Prostheses were all single crowns. In all cases, a spiral implant 2–4 mm longer than the residual bone was placed. Only two implants were lost due to peri-implantitis but subsequently replaced and followed-up. Bone loss values around the implants after three months (at the re-opening) ranged from 0 to 0.6 mm, (median value: 0.1 mm), while after two years, the same values ranged from 0.4 to 1.3 mm (median value: 0.7 mm). Clinical post-operative complications did not occur. After ten years, no implant has been lost. Overall, the described protocol seems to show good results in terms of predictability and patient compliance
Cosmic-ray interactions with the Sun
The solar disk is a bright gamma-ray source in the sky. The interactions of cosmic rays with the solar atmosphere produce secondary particles which can reach the Earth. In this work we present a comprehensive calculation of the yields of secondary particles such as gamma-rays, electrons, positrons, neutrons and neutrinos, performed with the FLUKA code. We also estimate the intensity at the Sun and the fluxes at the Earth of these secondary particles by folding their yields with the intensities of cosmic rays impinging on the solar surface. The results are sensitive to the assumptions on the magnetic field near the Sun and to the cosmic-ray transport in the magnetic field in the inner solar system
Search for Early Gamma-ray Production in Supernovae Located in a Dense Circumstellar Medium with the Fermi LAT
Supernovae (SNe) exploding in a dense circumstellar medium (CSM) are
hypothesized to accelerate cosmic rays in collisionless shocks and emit GeV
gamma rays and TeV neutrinos on a time scale of several months. We perform the
first systematic search for gamma-ray emission in Fermi LAT data in the energy
range from 100 MeV to 300 GeV from the ensemble of 147 SNe Type IIn exploding
in dense CSM. We search for a gamma-ray excess at each SNe location in a one
year time window. In order to enhance a possible weak signal, we simultaneously
study the closest and optically brightest sources of our sample in a
joint-likelihood analysis in three different time windows (1 year, 6 months and
3 months). For the most promising source of the sample, SN 2010jl (PTF10aaxf),
we repeat the analysis with an extended time window lasting 4.5 years. We do
not find a significant excess in gamma rays for any individual source nor for
the combined sources and provide model-independent flux upper limits for both
cases. In addition, we derive limits on the gamma-ray luminosity and the ratio
of gamma-ray-to-optical luminosity ratio as a function of the index of the
proton injection spectrum assuming a generic gamma-ray production model.
Furthermore, we present detailed flux predictions based on multi-wavelength
observations and the corresponding flux upper limit at 95% confidence level
(CL) for the source SN 2010jl (PTF10aaxf).Comment: Accepted for publication in ApJ. Corresponding author: A. Franckowiak
([email protected]), updated author list and acknowledgement
Multiwavelength Evidence for Quasi-periodic Modulation in the Gamma-ray Blazar PG 1553+113
We report for the first time a gamma-ray and multi-wavelength nearly-periodic
oscillation in an active galactic nucleus. Using the Fermi Large Area Telescope
(LAT) we have discovered an apparent quasi-periodicity in the gamma-ray flux (E
>100 MeV) from the GeV/TeV BL Lac object PG 1553+113. The marginal significance
of the 2.18 +/-0.08 year-period gamma-ray cycle is strengthened by correlated
oscillations observed in radio and optical fluxes, through data collected in
the OVRO, Tuorla, KAIT, and CSS monitoring programs and Swift UVOT. The optical
cycle appearing in ~10 years of data has a similar period, while the 15 GHz
oscillation is less regular than seen in the other bands. Further long-term
multi-wavelength monitoring of this blazar may discriminate among the possible
explanations for this quasi-periodicity.Comment: 8 pages, 5 figures. Accepted to The Astrophysical Journal Letters.
Corresponding authors: S. Ciprini (ASDC/INFN), S. Cutini (ASDC/INFN), S.
Larsson (Stockholm Univ/KTH), A. Stamerra (INAF/SNS), D. J. Thompson (NASA
GSFC
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