Perspectives of 2D and 3D mapping of atmospheric pollutants over urban areas by means of airborne DOAS spectrometers

tants, offering numerous advantages over conventional networks of in situ analysers. We propose some innovative solutions in the field of DOAS (Differential Optical Absorption Spectroscopy) remote systems, utilizing diffuse solar light as the radiation source. We examine the numerous potentialities of minor gas slant column calculations, applying the «off-axis» methodology for collecting the diffuse solar radiation. One of these particular approaches, using measurements along horizontal paths, has already been tested with the spectrometer installed on board the Geophysica aircraft during stratospheric flights up to altitudes of 20 km. The theoretical basis of these new measurement techniques using DOAS remote sensing systems are delineated to assess whether low altitude flights can provide 2D and 3D pollution tomography over metropolitan areas. The 2D or 3D trace gas total column mapping could be used to investigate: i) transport and dispersion phenomena of air pollution, ii) photochemical process rates, iii) gas plume tomography, iv) minor gas vertical profiles into the Planetary Boundary Layer and v) minor gas flux divergence over a large area

Status of the SPARC-X Project

SPARC-X is a two branch project consisting in the SPARC test facility dedicated to the development and test of critical subsystems such as high brightness photoinjector and a modular expandable undulator for SASE-FEL experiments at 500 nm with seeding, and the SPARX facility aiming at generation of high brilliance coherent radiation in the 1.5-13 nm range, based on the achieved expertise. The projects are supported by MIUR (Research Department of Italian Government) and Regione Lazio. SPARC has completed the commissioning phase of the photoinjector in November 2006. The achieved experimental results are here summarized together with the status of the second phase commissioning plans. The SPARX project is based on the generation of ultra high peak brightness electron beams at the energy of 1 and 2 GeV generating radiation in the 1.5-13 nm range. The construction is at the moment planned in two steps starting with a 1 GeV Linac. The project layout including both RF-compression and magnetic chicane techniques has been studied

Reply to "comment on 'new experimental data and reference models for the viscosity and density of squalane"

The authors would like to thank Professor Bair for his insightful comments on ultrahigh-pressure viscosities. The viscosity model used by Schmidt et al.1 was a Tait-like2,3 model that has been shown to correlate accurately the viscosity of many fluids in the original investigation’s pressure range (0.1–275.8 MPa (40000 psi)) of interest. The upper pressure is indicative of the high pressures found in the petroleum industry4. However, after discussions with Professor Bair, it became clear a reference model that can accurately model the viscosity of squalane at ultrahigh-pressures is of interest to those working in the area of tribology

Thermal Band Atmospheric Correction Using Atmospheric Profiles Derived from Global Positioning System Radio Occultation and the Atmospheric Infrared Sounder

This Rapid Prototyping Capability study explores the potential to use atmospheric profiles derived from GPS (Global Positioning System) radio occultation measurements and by AIRS (Atmospheric Infrared Sounder) onboard the Aqua satellite to improve surface temperature retrieval from remotely sensed thermal imagery. This study demonstrates an example of a cross-cutting decision support technology whereby NASA data or models are shown to improve a wide number of observation systems or models. The ability to use one data source to improve others will be critical to the GEOSS (Global Earth Observation System of Systems) where a large number of potentially useful systems will require auxiliary datasets as input for decision support. Atmospheric correction of thermal imagery decouples TOA radiance and separates surface emission from atmospheric emission and absorption. Surface temperature can then be estimated from the surface emission with knowledge of its emissivity. Traditionally, radiosonde sounders or atmospheric models based on radiosonde sounders, such as the NOAA (National Oceanic & Atmospheric Administration) ARL (Air Resources Laboratory) READY (Real-time Environmental Application and Display sYstem), provide the atmospheric profiles required to perform atmospheric correction. Unfortunately, these types of data are too spatially sparse and too infrequently taken. The advent of high accuracy, global coverage, atmospheric data using GPS radio occultation and AIRS may provide a new avenue for filling data input gaps. In this study, AIRS and GPS radio occultation derived atmospheric profiles from the German Aerospace Center CHAMP (CHAllenging Minisatellite Payload), the Argentinean Commission on Space Activities SAC-C (Satellite de Aplicaciones Cientificas-C), and the pair of NASA GRACE (Gravity Recovery and Climate Experiment) satellites are used as input data in atmospheric radiative transport modeling based on the MODTRAN (MODerate resolution atmospheric TRANsmittance) radiative transport software to separate out the atmospheric component of measured top of atmosphere radiance. Simulated water bodies across a variety of MODTRAN model atmospheres including desert, mid-latitude, tropical and sub-artic conditions provide test bed conditions. Atmospherically corrected radiance and surface temperature results were compared to those obtained using traditional radiosonde balloon data and models. In general, differences between the different techniques were less than 2 percent indicating the potential value satellite derived atmospheric profiles have to atmospherically correct thermal imagery

MAXILLARY SINUS LIFT THROUGH HETEROLOGOUS BONE GRAFTS AND SIMULTANEOUS ACID-ETCHED IMPLANTS PLACEMENT. FIVE YEAR FOLLOW-UP

Abstract AIM: The aim of this study was to assess retrospectively at 5 years the clinical outcome of bone regeneration in patients who underwent maxillary sinus lift with different equine-derived, enzyme-deantigenated equine bone grafts, and simultaneous placement of acid-etched surface implants. METHODS: Eighteen patients (10 males and 8 females, age between 55 and 61 years) were considered. They were divided into 2 groups according to the type of bone graft used: a combination of an equine flexible heterologous spongy bone layer (Osteoplant Flex, Bioteck) and equine heterologous cortical and spongy granules (Bio-Gen Mix, Bioteck), group A, or a block of equine heterologous spongy bone (Bio-Gen Block, Bioteck), group B. Surface-treated implants (''TRE'' type, Biotec) were placed simultaneously to sinus augmentations and usual clinical and radiological tests were performed at 6 months and every year up to 5 years after surgery. RESULTS: At 5 years, 45 out of 49 total implants placed (91.8%) were successful according to the Albrektsson and Zarb criteria. The loss of the 4 failed implants was observed in 2 patients of group B during the first days following surgery. CONCLUSION: These results show that the heterologous bone grafts supported properly the bone regeneration inside the sinuses, and that the type of implants used allowed to achieve a satisfying rate of success according to the current standards in implantology. PMID: 18427440 [PubMed - indexed for MEDLINE

Region Merging Driven by Deep Learning for RGB-D Segmentation and Labeling

Among the various segmentation techniques, a widely used family of approaches are the ones based on region merging, where an initial oversegmentation is progressively refined by joining segments with similar characteristics. Instead of using deterministic approaches to decide which segments are going to be merged we propose to exploit a convolutional neural network which takes a couple of segments as input and decides whether to join or not the segments. We fitted this idea into an existent iterative semantic segmentation scheme for RGB-D data. We were able to lower the number of free parameters and to greatly speedup the procedure while achieving comparable or even higher results, thus allowing for its usage in free navigation systems. Furthermore, our method could be extended straightforwardly to other fields where region merging strategies are exploited

Perspectives of 2D and 3D mapping of atmospheric pollutants over urban areas by means of airborne DOAS spectrometers

tants, offering numerous advantages over conventional networks of in situ analysers. We propose some innovative solutions in the field of DOAS (Differential Optical Absorption Spectroscopy) remote systems, utilizing diffuse solar light as the radiation source. We examine the numerous potentialities of minor gas slant column calculations, applying the «off-axis» methodology for collecting the diffuse solar radiation. One of these particular approaches, using measurements along horizontal paths, has already been tested with the spectrometer installed on board the Geophysica aircraft during stratospheric flights up to altitudes of 20 km. The theoretical basis of these new measurement techniques using DOAS remote sensing systems are delineated to assess whether low altitude flights can provide 2D and 3D pollution tomography over metropolitan areas. The 2D or 3D trace gas total column mapping could be used to investigate: i) transport and dispersion phenomena of air pollution, ii) photochemical process rates, iii) gas plume tomography, iv) minor gas vertical profiles into the Planetary Boundary Layer and v) minor gas flux divergence over a large area