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Aim: A range of CT characteristics with potential prognostic value have previously been identified for gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs). Still, there is no widely accepted consensus on which characteristics should be reported as prognostic factors. This systematic review therefore aims to provide an overview of the available literature regarding CT characteristics and their prognostic significance for GEP-NET patients. Materials and methods: PubMed, Embase, and Scopus/Cochrane Library databases were searched and a forward and backward reference check of the identified studies was executed. Eligible studies were conducted in patients with GEP-NET, and reported on the prognostic significance (in terms of tumor grade, spread of disease, and survival) of CT-based biomarkers. Study selection, quality assessment and data extraction were performed by two reviewers independently, resolving disagreement by consensus. Results: In total, 5074 unique studies were identified, of which 37 were included. Given the paucity of data on GEP-NETs other than PNET, data extraction and analyses was restricted to PNETs. Fourteen CT characteristics were correlated to prognostic outcomes. Larger tumor size, hypo-enhancement, irregular shape and ill-defined margins, presence of locally invasive growth, lymphadenopathy and metastases were predictors of poorer prognosis according to 65–89% of the available studies. Most studies were regarded as having a low (65%) or moderate (24%) risk of bias. Conclusion: Evidence regarding prognostic value of CT-based biomarkers for PNETs is limited to heterogeneous, retrospective studies. Nonetheless, heterogeneity in data is more likely to obscure than to overestimate any correlation. Therefore, we feel that the before-mentioned characteristics should be regarded and reported as clinically relevant predictors of poorer prognosis.

This paper presents the project Earth Cooling by Water Vapor Radiation, an observational programme, which aims at developing a database of spectrally resolved far infrared observations, in atmospheric dry conditions, in order to validate radiative transfer models and test the quality of water vapor continuum and line parameters. The project provides the very first set of far-infrared spectral downwelling radiance measurements, in dry atmospheric conditions, which are complemented with Raman Lidar-derived temperature and water vapor profiles. Citation: Bhawar, R., et al. (2008), Spectrally resolved observations of atmospheric emitted radiance in the H2O rotation band.

Polar stratospheric clouds (PSC) were observed with the multi-wavelength lidar of the MOANA project (Modelling and Observations of Aerosols in the Northern Atmosphere) during SESAME (Second European Stratospheric Arctic and Mid-latitude Experiment). The physical state, liquid or solid, of the cloud particles can be inferred from the lidar data. Using isentropic back-trajectories to obtain the thermal history of the sampled air masses, it is possible to reconcile most of the observations with current ideas on PSC formation and evolution. When the cloud particles were identified as liquid, changes in the size distribution of the droplets along the trajectory were calculated using a micro-physical box model. Backscatter ratios calculated from the size distributions are in broad agreement with the lidar data, giving confidence in current understanding of the evolution of ternary solution (H2SO4, HNO3 and H2O) droplets. Results from two soundings are shown which bear on the problem of the formation of solid particles. In the first, solid particles were detected. The air mass had cooled to the frost point 12 hours earlier. In the second no solid particles were detected although the air temperature was below the nitric acid trihydrate existence point, and had decreased by 12K in the previous 14 hours.

ALISEO (Aerospace Leap-frog Imaging Stationary Interferometer for Earth Observation) belongs to the stationary interferometers representing a promising architecture for future Earth Observation (EO) sensors due to their simple optical layout. ALISEO has been selected by the Italian Space Agency as the principal payload for a new optical mission based on a micro-satellite (MIOsat). Payloads planned for MIOsat are an extensible telescope, a high-resolution panchromatic camera, a Mach-Zehnder MEMS interferometer, and ALISEO. MIOsat is expected to provide a platform with pointing capability for those advanced sensors. ALISEO operates in the common-path Sagnac configuration, and it does not employ any moving part to generate phase delay between the two rays. The sensor acquires the target images modulated by a pattern of autocorrelation functions: a fringe pattern that is fixed with respect to the instrument's field of view. The complete interferogram of each target location is retrieved introducing relative source-observer motion, which allows any image pixels to be observed under different phase delays. Recent laboratory measurements performed with ALISEO are described and discussed in this paper. In order to calibrate the optical path difference (OPD) of raw interferograms, a set of measurements have been carried out using a double planar diffuser system and several coloured He-Ne lasers. Standard reflectance tiles together doped with Holmium and Rare Earths have been used for validating the wavelength calibration of the instrument and proving the reliability of the reflectance retrieving procedure.

A polarization lidar operating at 532 nm was converted into an automatic, polarimetric lidar capable of measuring the entire Stokes vector of backscattered light and its derived quantities. Among these quantities, circular and linear depolarizations were studied as tools for investigating the presence of anisotropic scattering media. Isotropic scatterers show a simple relationship between linear and circular depolarization, a relation that we confirm theoretically and experimentally. Deviations from this relation, which are possible in the presence of anisotropic scatterers such as horizontally oriented ice plates when they are observed with a slant lidar, were studied both numerically and experimentally.

The first spectral measurement of Earth’s emitted radiation to space in the widebandrange from 100 to 1400cm −1 with 0.5cm −1 spectral resolution is presented. The mea-surement was performed from a stratospheric balloon in tropical region using a Fourier 5 transform spectrometer, during a field campaign held in Brazilin June2005. The instru-ment, which has uncooled components including the detector module, is a prototypedeveloped as part of the study for the REFIR (Radiation Explorer in the Far InfraRed)space mission. This paper shows the results of the field campaign with particular atten-tion to the measurement capabilities of the prototype. The results are compared with 10 measurements taken by IASI-balloon (Infrared Atmospheric Sounding Interferometer –Balloon version), aboard the same platform, and with forward model estimations. Theinfrared signature of clouds is observed in the measurements. 1 Introduction The observation of the upwelling emission in the full relevant spectral range, from the

In preparation for a possible space mission, a breadboard version named REFIR-BB of the Radiation Explorer in the Far Infrared (REFIR) instrument has been built. The REFIR is a Fourier-transform spectrometer with a new optical layout operating in the spectral range 100-1100 cm(-1) with a resolution of 0.5 cm(-1), a 7-s acquisition time, and a signal-to-noise ratio of better than 100. Its mission is the spectral measurement in the far infrared of the Earth's outgoing emission, with particular attention to the long-wavelength spectral region, which is not covered by either current or planned space missions. This measurement is of great importance for deriving an accurate estimate of the radiation budget in both clear and cloudy conditions. The REFIR-BB permits the trade-off among all instrument parameters to be studied, the optical layout to be tested, and the data-acquisition strategy to be optimized. The breadboard could be used for high-altitude ground-based campaigns or could be flown for test flights on aircraft or balloon stratospheric platforms. The breadboard's design and the experimental results are described, with particular attention to the acquisition strategy and characterization of the interferometer. Tests were performed both in laboratory conditions and in vacuum. Notwithstanding a loss of efficiency above 700 cm(-1) caused by the poor performance of the photolithographic polarizers used as beam splitters, the results demonstrate the feasibility of using the spectrometer for space applications.

Pyrgi, cittadina etrusca e colonia romana, posta sulle coste del Tirreno fra Roma e Civitavecchia, fu visitata e descritta da molti archeologi e topografi del secolo scorso, ma non é stata oggetto di studi topografici recenti. Queste brevi note vogliono illustrare con maggior precisione alcuni punti fondamentali della sua topografia. La ricerca é stata molto facilitata dall'uso delle fotografie aeree esistenti nella Scuola Britannica, una delle quali ripresa nel maggio 1944 é qui riprodotta (pl. III; cfr. fig. 1, dove indichiamo gli elementi ricavati dalla fotografia o accertati sul terreno e, a trattini, le linee fondamentali della topografia moderna).Sul luogo di Pyrgi esiste oggi il castello di Santa Severa (pl. IV, a) al quale conduce una breve strada che si distacca dall'Aurelia al chilometro 52,550. Un recinto medievale di fortificazione con piccole torri sporgenti, costruito in blocchetti quadrangolari di arenaria, fa capo ad un'alta rocca quadrilatera con torri ai quattro angoli. Separate da essa e collegato solamente con un aereo ponte di legno é il torrione maestro cilindrico, in posizione dominante sulla riva del mare.Una memoria del martirio di Santa Severa si legge negli Acta Sanctorum 29 gennaio vol. ii, p. 946 sg. dove si hanno le seguenti determinazioni topografiche: Centumcellae, milliario XXXV ab urbe iuxta mare … in loco qui dicitur Pignus.

International audience; The first spectral measurement of Earth's emitted radiation to space in the wideband range from 100 to 1400 cm-1 with 0.5 cm-1 spectral resolution is presented. The measurement was performed from a stratospheric balloon in tropical region using a Fourier transform spectrometer, during a field campaign held in Brazil in June 2005. The instrument, which has uncooled components including the detector module, is a prototype developed as part of the study for the REFIR (Radiation Explorer in the Far InfraRed) space mission. This paper shows the results of the field campaign with particular attention to the measurement capabilities of the prototype. The results are compared with measurements taken by IASI-balloon (Infrared Atmospheric Sounding Interferometer – Balloon version), aboard the same platform, and with forward model estimations. The infrared signature of clouds is observed in the measurements.