1,233 research outputs found

    Numerical simulations of mountain winds in an alpine valley

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    The meteorological model WRF is used to investigate the wind circulation in Valle Camonica, Italy, an alpine valley that includes a large subalpine lake. The aim was to obtain the information necessary to evaluate the wind potential of this area and, from a methodological point of view, to suggest how numerical modeling can be used to locate the most interesting spots for wind exploitation. Two simulations are carried out in order to analyze typical scenarios occurring in the valley. In the first one, the diurnal cycle of thermally-induced winds generated by the heating-cooling of the mountain range encircling the valley is analyzed. The results show that the mountain slopes strongly affect the low-level winds during both daytime and nighttime, and that the correct setting of the lake temperature improves the quality of the meteorological fields provided by WRF significantly. The second simulation deals with an event of strong downslope winds caused by the passage of a cold front. Comparisons between simulated and measured wind speed, direction and air temperature are also shown

    Intensive archaeological survey at Piscina Torta:use of a low-cost RTK portable kit to materialise a UTM grid on the ground

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    We tested the use of a low-cost GPS RTK to set up a grid during the intensive archaeological survey of the Piscina Torta site, in the framework of the Salt and Power project of the University of Groningen. We also suggest not using a local grid but the WGS84 UTM grid and naming the single cells with the coordinates of one of its vertices. This would facilitate the use and exchange of the data (e.g. about the potsherds collected in the cell) among the scientific community

    The breadth-degree type of a finite p-group

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    In the present paper we show that a stem finite p-group G has size bounded by min(p^(8d 122log2d+b 124)(b+1)/2,p^b(3b+4d 121)/2) where b is the breadth of G and pd is the maximum character degree of G. As a consequence there are only finitely many finite stem p-groups having breadth b and maximum character degree pd

    Intensive archaeological survey at Piscina Torta:use of a low-cost RTK portable kit to materialise a UTM grid on the ground

    Get PDF
    We tested the use of a low-cost GPS RTK to set up a grid during the intensive archaeological survey of the Piscina Torta site, in the framework of the Salt and Power project of the University of Groningen. We also suggest not using a local grid but the WGS84 UTM grid and naming the single cells with the coordinates of one of its vertices. This would facilitate the use and exchange of the data (e.g. about the potsherds collected in the cell) among the scientific community

    How to circumvent the limitations of open source software and orthorectify how (or better) than with commercial software

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    High and very high resolution satellite images are now an irreplaceable resource for earth observation in general and for the extraction of hydrogeological information in particular. In order to use them correctly and compare them with previous surveys and maps, they must be treated geometrically to removethedistortions introduced by the acquisition process. Orthorectification is not a simple georeferencing because the process must take into account the three-dimensional acquisition geometry of the sensor. For this reason orthorectification must be performed within specific commercial software with additional costs compared to image acquisition which, in some cases, is currently free of charge. Some orthorectification algorithms, mainly based on the RPC approach, are available in open source GIS software such as QGIS. OTB (Orpheus toolbox) for QGIS contains some of these algorithms but its interfaces are not clear and there are some incomprehensible limitations such as the impossibility to input three-dimensional ground control points (GCPs). This severely limits the final achievable accuracy because it does not allow to correctly estimate the influence of different ground morphologies on the acquisition geometry. To get around these limitations you can make a "pseudo DEM" and other expedients to complete the whole process obtaining absolute results comparable if not better than those of commercial software. The proposed procedure may not be the fastest but it can be a valid alternative for those who use satellite images as a tool in their research work

    Oncoplastic central quadrantectomies

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    Tumors localized in the central quadrant (centrally located breast tumors) have always represented a challenge for the surgeon because of the critical aesthetical matters related to the nipple-areola complex (NAC). Many years of experience with breast cancer patients treated by using various oncoplastic techniques, has allowed us to develop the modified hemibatwing for the treatment of central breast tumors, where the NAC is involved. Modified hemibatwing-along with the removal of the NAC-is a useful oncoplastic technique and it represents an ideal option for the treatment of central tumors because it assures oncological safety, a reduced surgical timetable and greater aesthetical results

    The metal-nonoate Ni(SalPipNONO) inhibits in vitro tumor growth, invasiveness and angiogenesis

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    Nitric oxide (NO) exerts conflicting effect on tumor growth and progression, depending on its concentration. We aimed to characterize the anti-cancer activity of a new NO donor, Ni(SalPipNONO) belonging to the class of metal-nonoates, in epithelial derived tumor cells, finally exploring its antiangiogenic properties. Tumor epithelial cells were screened to evaluate the cytotoxic effect of Ni(SalPipNONO), which was able to inhibit cell proliferation in a dose dependent manner, being more effective than the commercial DETA/NO. The human lung carcinoma cells A549 were chosen as model to study the anti-cancer mechanisms exerted by the compound. In these cells, Ni(SalPipNONO) inhibited clonogenicity and cell invasion, while promoting apoptosis. The antitumor activity was partly due to NO-cGMP dependent pathway, contributing to reduced cell number and apoptosis, and partly to the salicylaldehyde moiety and reactive oxygen species (ROS) activated ERK1/2 signaling converging on p53 dependent caspase-3 cleavage. An additional contribution by downstream cycloxygenase-2 (COX-2) derived cyclopentenones may explain the tumor inhibitory activities. As NO has been described to affect tumor angiogenesis, we checked this activity both on tumor and endothelial cell co-cultures and in Matrigel in vivo assay. Our data document that Ni(SalPipNONO) was able to both reduce angiogenic factor expression by tumor cells acting on hypoxia inducible factor-1α (HIF-1 α) level, and endothelial cell functions related to angiogenesis. Collectively, these data confirm the potential use of NO donors and in particular Ni(SalPipNONO) acting through multiple mechanisms, as an agent to be further developed to be used alone or in combination with conventional therapy
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