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Appropriate end of life (EOL) management in Internal Medicine wards is challanging. The aim of this study was to analyze the burden of an educational program on EOL management in a Internal Medicine ward. Materials and methods: We retrospectively analysed characteristics and management of patients consecutively died in an italian Internal Medicine ward along one year. We compared demographic, co-morbidity, pharmacological treatment in the last 48-hours of life and procedures during hospital stay in patients died six months before and after an educational program on palliative cares and EOL management addressed to a team of physicians and nurses.Study population was composed by 354 patients (190 females), with mean age ± DS 83.5 ± 10.6 years, one half admitted after the educational program. Eighty-four percent of deaths was exepected in the last 48 hours before exitus. Demographic characteristics and causes of hospitalization were not different before and after educational program. After the educational program the sharing of palliative care program with patient, relatives and/or caregivers (97.7% vs 85.8%, p=0.0001) and written order to withdrawal vital parameters relevation (39.5% vs 22%, p=0.0005) significantly increased, while difference in pharmacological classes prescribed in the last 48 hours of life was not find. Blood (54.8% vs 67.2%, p=0.0219) and arterial gas analysis (28.8% vs 39.5%, p=0.0435) samples in the last 48 hours of life were significantly reduced. Radiological and/or endoscopic examinations, red cells or platelets transfusion were reduced and palliative therapy was increased, despite difference between the two periods was not statistically significant.Educational program in Internal Medicine wards aimed to improve skills could contribute to make EOL management more appropriate and patient-oriented and it should be strongly encour-aged.

The multichromatic analysis (MCA) uses interferometric pairs of SAR images processed at range subbands and explores the phase trend of each pixel as a function of the dif- ferent central carrier frequencies to infer absolute optical path difference. This approach allows retrieving unambiguous height information on selected pixels, potentially solving the problem of spatial phase unwrapping, which is instead critical in the stan- dard monochromatic processing. The method, based on concepts originally introduced by Madsen and Zebker, has been developed in previous work both theoretically and through simulations. This paper presents the first MCA experimental validation of the procedure, through application to a wideband SAR single-pass interferometric data set acquired by the AES-1 airborne sensor. An evaluation of the impact of theMCA processing parameters on the height estimation performances is obtained through a para- metric analysis. The results confirm the indications derived by the theoretical analysis, demonstrating the feasibility of the MCA absolute phase measurement, provided that a sufficient bandwidth is available.

Because of possible multiple solutions allowed, the unwrapping of interferometric fringe patterns in the spatial domain is an ill-posed problem which needs some a priori knowledge of the ground morphology for the solution of ambiguities. This is especially true for interferometric SAR (Synthetic Aperture Radar) data. In this paper we propose a different approach to InSAR processing for retrieving the height of ground points independently from each other, unlike most conventional phase unwrapping procedures, which operate in the spatial domain. The basic idea is to repeat raw data focusing by using range sub-bands centered at different frequencies, in order to find a point history of the interferometric phase variation vs. frequency. We introduce the general framework of the method together with considerations on the theoretical limits of applicability, then we report results of our simulations related to a wide-band SAR system. We show that, under certain conditions, height values can be retrieved over a network of coherent and strong scatterers, even when enclosed into low-coherence areas.

This work investigates the possibility of performing target analysis through the Multi-Chromatic Analysis (MCA), a technique that basically explores the information content of sub-band images obtained by processing portions of the range spectrum of a synthetic aperture radar (SAR) image. According to the behavior of the SAR signal at the different sub-bands, MCA allows target classification. Two strategies have been experimented by processing TerraSAR-X images acquired over the Venice Lagoon, Italy: one exploiting the phase of interferometric sub-band pairs, the other using the spectral coherence derived by computing the coherence between sub-band images of a single SAR acquisition. The first approach introduces the concept of frequency-persistent scatterers (FPS), which is complementary to that of the time-persistent scatterers (PS). FPS and PS populations have been derived and analyzed to evaluate the respective characteristics and the physical nature of the targets. Spectral coherence analysis has been applied to vessel detection, according to the property that, in presence of a random distribution of surface scatterers, as for open sea surfaces, spectral coherence is expected to be proportional to sub-band intersection, while in presence of manmade structures it is preserved anyhow. First results show that spectral coherence is well preserved even for very small vessels, and can be used as a complementary information channel to constrain vessel detection in addition to classical Constant False Alarm Rate techniques based on the sole intensity channel.

The multichromatic analysis (MCA) can be applied to interferometric pairs of synthetic aperture radar (SAR) images processed at range subbands and consists of exploring the phase trend of each pixel as a function of the different central carrier frequencies. The phase of stable scatterers linearly evolves with the subband central frequency, with a slope proportional to the absolute electromagnetic path difference that can be estimated and used for both phase unwrapping and height computation. MCA has been theoretically evaluated and tested on airborne wideband SAR data, appearing optimally suited for the new generation of satellite sensors, which operate with larger bandwidths than previously available instruments, generally limited to few tens of megahertzs. In this letter, we illustrate MCA application to satellite SAR data acquired in spotlight mode over the Uluru monolith in Australia. The topographic measurements derived through MCA on the monolith are compared with those provided by a high-resolution digital elevation model from optical stereo imagery. The theoretical parametric model describing the MCA performances according to the processing parameters is also validated.

Multi-Chromatic Analysis (MCA) of SAR images relays on exploring sub-band images obtained by processing portions of range spectrum located at different frequency positions. It has been applied to interferometric pairs for phase uwrapping and height computation. This work investigates two promising applications: the comparison between the frequency-persistent scatterers (PS fd ) and the temporal-persistent scatterers (PS), and the use of inter-band coherence of a single SAR image for vessel detection. The MCA technique introduces the concept of frequency-stable targets, i.e. objects exhibiting stable radar returns across the frequency domain which is complementary to that of temporal stability at the base of PS interferometry. Both spotlight and stripmap TerraSAR-X images acquired on the Venice Lagoon have been processed to identify PS fd and PS. Different populations have been analyzed to evaluate the respective characteristics and the physical nature of PS fd and PS. Concerning the spectral coherence, it is derived by computing the coherence between sub-images of a single SAR acquisition. In the presence of a random distribution of surface scatterers, spectral coherence must be proportional to sub-band intersection of sub-images. This model is fully verified when observing measured spectral coherence on open see areas. If scatterers distribution departs from this distribution, as for manmade structures, spectral coherence is preserved. We investigated the spectral coherence to perform vessel detection on sea background by using spotlight images acquired on Venice Lagoon. Sea background tends to lead to very low spectral coherence while this latter is preserved on the targeted vessels, even for very small ones. A first analysis shows that all vessels observable in intensity images are easily detected in the spectral coherence images which can be used as a complementary information channel to constrain vessel detection.

The Multi-Chromatic Analysis (MCA) uses interferometric pairs of SAR images processed at range sub-bands and explores the phase trend of each pixel as a function of the different central carrier frequencies. The MCA technique introduces the concept of targets exhibiting stable radar returns across the frequency domain (PSfd). In this work we compare this stability along frequencies with the temporal stability which is at the base of persistent scatterers interferometry (PSI) techniques. Different populations of PSfd and “temporal” PS were derived by using COSMO-SkyMed SAR data. An ad hoc processing scheme was developed to derive PSI products by processing the same range sub-bandwidth used by the MCA in order to guarantee the same scattering conditions. The populations of PSfd and “temporal” PS were compared and preliminary considerations provided concerning the scattering properties of the targets selected by the two criteria.

The Multi-Chromatic Analysis can be applied to interferometric pairs of SAR images processed at range sub-bands, and consists of exploring the phase trend of each pixel as a function of the different central carrier frequencies. The phase of stable scatterers evolves linearly with the sub-band central wavelength, with a slope proportional to the absolute e. m. path difference. The technique appears optimally suited for the new generation of satellite sensors, which operate with larger bandwidths than previously available instruments, generally limited to few tens of MHz. A first experiment on satellite data was carried out by processing a spotlight interferometric pair of images acquired by TerraSAR-X on the well-known Uluru monolith in Australia. In the present work, we illustrate MCA processing on SAR data acquired over the same site by the COSMO-SkyMed constellation. The topographic profile of the monolith is successfully reconstructed. Furthermore, the results are also compared with those previously derived by processing TerraSAR-X data.

The Multi-Chromatic Analysis, as introduced in [1], uses interferometric pairs of SAR images processed at range sub-bands and explores the phase trend of each pixel as a function of the different central carrier frequencies. The phase of stable scatterers evolves linearly with the sub-band central wavelength, the slope being proportional to the absolute optical path difference. Unlike the standard "monochromatic" InSAR approach, this technique allows performing spatially independent and absolute topographic measurements, if the attention is focused on single targets exhibiting stable phase behaviour across the frequency domain. Potential applications for the study of frequency-stable targets include topographic measurement, atmospheric research, and urban monitoring. Through a simplified model [2], we obtained a first evaluation of the impact of the MCA processing parameters on the height estimation performances. A total bandwidth of at least 300 MHz seems to be required to provide reliable results. Thus, the technique appears optimally suited for the new generation of satellite sensors, which operate with larger bandwidths than previously available instruments, generally limited to few tens of MHz. SAR sensors such as those mounted on TerraSAR-X (TSX) or COSMO-SkyMed (CSK) spacecraft, all pose great expectations on the potential use of multi-chromatic methods. The practical feasibility of the technique was demonstrated in [2] by using a set of SAR data collected by the airborne AES-1 radar interferometer, operating at X-band by multi-channel electronics, which provides a total radar bandwidth of 400 MHz. A first successful application of the technique to satellite data was also shown in [3] by using a spotlight interferometric pair of images acquired by TSX on the well-known Uluru monolith in Australia. In the present work, we illustrate results obtained through MCA processing on spaceborne SAR data acquired by the CSK constellation both on Parkfield in California (USA), and on the Uuluru monolith. A CSK tandem pair acquired on the Uluru test site was used to validate the MCA-based height measurements by using a digital surface model (DSM) derived from optical stereo imagery captured at 15 cm resolution. The same dataset was also processed to validate the theoretical analysis [2] developed to assess the performance of the MCA with respect to the radiometric parameters involved in the processing (total bandwidth, sub-bandwidth, number of sub bands). The MCA technique introduces the concept of frequency-stable targets (PSfd), i.e. objects exhibiting stable radar returns across the frequency domain. This concept is complementary to that of temporal stability, which is at the base of persistent scatterers interferometry (PSI) techniques [4]. In PSI applications, stable targets (PS) are recognized as those exhibiting temporal stability through a stack of tens of SAR images. It is then natural to try to compare the two concepts, examining the assumptions which form the basis of the two definitions, and evaluating the respective characteristics of the two populations, with the final goal of ascertaining if any synergy can be identified between the two types of object. The Parkfield test site was used to attempt this comparison. A stack of 33 spotlight CSK acquisition was used to perform PSI through the SPINUA PSI algorithm [5]. Four tandem pairs selected within the multitemporal dataset were processed through MCA in order to derive four sets of PSfd to compare to the PS targets. An ad hoc processing scheme was developed to derive PSI products by processing the same range sub-bandwidth used by the MCA in order to guarantee the same scattering conditions. The populations of PSfd and "temporal" PS were compared and preliminary considerations provided concerning the scattering properties of the targets selected by the two criteria. Finally, we present potentials of MCA to measure absolute ranging by using a single SAR image. References [1]N. Veneziani, F. Bovenga, A. Refice, "A wide-band approach to absolute phase retrieval in SAR interferometry", Multidimensional Systems and Signal Processing, Vol. 14(1-2), pp. 183-205, 2003. [2]F. Bovenga, V. M. Giacovazzo, A. Refice, N. Veneziani, R. Vitulli, "Multi-Chromatic Analysis of InSAR data: validation and potential", Proceedings of FRINGE 2009, ESA-ESRIN, Frascati, Italy, Nov.30 - Dec. 4, 2009. [3]F. Bovenga, V. M. Giacovazzo, A. Refice, D. O. Nitti, N. Veneziani, "Interferometric multi-chromatic analysis of high resolution X-band data". Proceedings of FRINGE 2011, ESA-ESRIN, Frascati, Italy, Sept. 19-23, 2011. [4]A. Ferretti, C. Prati, and F. Rocca, "Permanent Scatterers in SAR Interferometry", IEEE Trans. Geosc. Remote Sens., vol. 39(1), pp. 8-20, 2001. [5]F. Bovenga, A. Refice, R. Nutricato, L. Guerriero, and M. T. Chiaradia, "SPINUA: a flexible processing chain for ERS/ENVISAT long term interferometry," in Proc. 2004 Envisat & ERS Symposium, Salzburg, Austria, 6-10 September, 2004.

The Multi-Chromatic Analysis (MCA) consists of performing sub-bands splitting in range frequency domain, thus generating chromatic views of lower range resolution, centered at different carrier frequencies. Multi-chromatic interferograms can be then generated by coupling chromatic views coming from an interferometric pair of SAR images. The interferometric phase of spectrally-stable scatterers evolves linearly with the sub-band central frequency, the slope being proportional to the absolute optical path difference. Unlike the standard "monochromatic" InSAR approach, this new technique allows performing spatially independent and absolute phase unwrapping (PU). Potential applications for the study of spectrally-stable targets include topographic measurements, atmospheric research or urban monitoring. The technique appears optimally suited for new-generation, wide-band, high-resolution satellite SAR sensors. This work presents first successful applications of the technique using both TerraSAR-X (TSX) and COSMO/SkyMed (CSK) spotlight data. In particular, we provide results concerning the use of MCA for performing absolute PU as well as for height measurement on a pixel-by-pixel basis. Moreover, the impact of coregistration procedure on the MCA-based inference is investigated.

L'osservazione della Terra da piattaforme spaziali, integrata con misure in situ e con acquisizione da piattaforme aeree, è una tecnologia di riferimento per il monitoraggio di ampie zone del Territorio con una elevata frequenza spaziale. Queste ca-ratteristiche sono essenziali per investigare, da un lato, l'effetto di modifiche indotte da cambiamenti climatici, dall'altro la presenza di situazioni che siano precursori di cambiamenti, in un'ottica di previsione ed allerta. Nel presente lavoro vengono presentati alcuni esempi applicativi in questo scenario.

The present paper presents the results of the application of Multi Chromatic Analysis (MCA) for height retrieval by processing both AES-1 airborne data and satellite TerraSAR-X data. In particular, a test of the robustness of the MCA technique with respect to total processed bandwidth has been performed through comparison of results from datasets with bandwidths spanning form 100 to 400 MHz. A first validation of the mentioned technique has been carried out by comparing the retrieved heights w.r.t. ground elevation from external SRTM DEM, as well as by verifying the reliability of the fringe classifications based on the integer number of phase cycles computed through MCA. Results are presented and commented by addressing potential and limitation of the technique.

On sequential computers, the prime factor algorithm (PFA) allows the Computation of the discrete Fourier transform (DFT) with a higher efficiency than the traditional Cooley-Tukey FFT algorithm (CTA). However, the PFA requires substantial data movement, which poses a challenging problem for distributed-memory multi-processor systems. In this paper, two approaches for a concurrent implementation of the PFA on these structures are presented. In the first approach, the concurrent PFA runs on all nodes of the multi-processor system, which is inefficient on large configurations due to the large communication overhead. A second approach developed to reduce this bottleneck is also presented. These solutions have been benchmarked on Caltech hypercubes, and the performances achieved are reported. In both approaches, the crystal_router algorithm was exploited as a concurrent technique for communicating data among nodes.

The prime factor algorithm (PFA) is an efficient discrete Fourier transform (DFT) computation algorithm in which a one-dimensional DFT is tuned into a multidimensional DFT, consisting of a few short DFTs whose lengths are mutually prime, and then an efficient algorithm is used for the short DFTs. The PFA was implemented on a hypercube using CrOS III communication routines, taking 120 ms to compute the DFT of 5040 complex points using 32 nodes of the Caltech-JPL MARK III Hypercube. It took 105 ms to do a DFT of 4096 complex points using the Cooley-Tukey algorithm with the same hardware configuration. The performance of hypercubes MARK III, NCUBE, and iPSC and the relative importance of communication and calculation are analyzed. With the current communication speed the Cooley-Tukey algorithm performs fast on a massively concurrent processor and the PFA is advantageous when the number of processors is less than 64 or so. The experience with using the PFA also serves as a useful guide to a multidimensional fast Fourier transform implementation using any algorithm. >

Use of mean-field annealing theory is proposed for solving the phase-unwrapping (PU) problem. PU is formulated as a constrained optimization problem for the field of integer corrections to be added to the wrapped gradient field. A deterministic algorithm is described to provide an approximation of the average of the correction field over the global minima of the cost function. The proposed algorithm can be applied for any choice of the cost function. Using a cost function based on second-order differences, we obtain results close to those from simulated annealing and spend less computational time.

In recent years, attention has been devoted to the possibility of retrieving accurate phase information from stable targets in long SAR data series through Permanent Scatterers Interferometry (PSI), SBAS approach or equivalent methods. Recently, alternative methods for detecting stable targets on single images have been investigated. In particular, the availability of new SAR sensors provided with innovative features, including a wider transmitted bandwidth, allows to explore backscatter stability in the new dimension given by spectral diversity. The Multi-Chromatic Phase (MCP) approach, introduced in [2], uses images processed at range sub-bands and explores the phase trend of each pixel as a function of the different central carrier frequencies. In this paper we present the results of the application of this technique to point target detection. We compare the results with an alternative method proposed in [5] which identifies scatterers with stable spectral behavior.

Objective:Perioperativemyocardialischemiaislesspronouncedinoff-pumpcoronaryarterybypass(OPCAB)comparedtoon-pumpcoronary arterybypass;however,thethreshold overwhichthepostoperativereleaseofcardiactroponinI(cTnI)releaseand creatinekinase-MB(CK-MB) after OPCAB should be considered clinically relevant is unknown. The study was designated to evaluate if perioperative myocardial damage, measured by means of postoperative release of cTnI and CK-MB, has an influence on short- and mid-term outcome after OPCAB operations. Methods: Two hundred and sixty-one unselected patients undergoing OPCAB had cTnI and CK-MB measured preoperatively and nine times postoperatively. Postoperative peak values were evaluated and the 80thpercentiles wereused to segregate the populationinto two groups for each marker. The following cut-offs were used: 7.1 ng/dl for cTnI peak and 36.3 ng/dl for CK-MB peak.Results:Patients with cTnI >7.1 ng/ml (n =5 1) and CK-MB>36.3 ng/ml (n = 48) had a longer mechanical ventilation and ICU length of stay. Nevertheless, hospital mortality did not differ between groups. Survival after 3 years was 92.8 2.3% and 81.8 6.2 for patients with postoperative cTnI peak 7.1 ng/ml and >7.1 ng/ml, respectively (p = 0.003). It was 93 2.2% and 80 6.8% for patients with CK-MB 36.3 ng/ml and >36.3 ng/ml, respectively (p = 0.005). Adjusted hazard ratios for mid-term mortality were HR 2.7 (CI 1—7.6),p =0 .05 for cTnI>7.1 ng/dl and HR 3.1 (CI 1—9.1),p =0 .04 for CK-MB >36.3 ng/ml. Conclusion: Perioperative myocardial damage should not be considered an innocuous event following OPCAB operations since the survival rate over 3 years is significantly worse in patients with the highest postoperative peak release of cTnI and CK-MB.

The differential analysis in the frequency domain, or multi-chromatic approach to SAR-interferometry, offers as its main advantage the retrieval of the absolute phase of targets, providing an alternative to the phase unwrapping algorithms in the spatial domain. On the other hand, a correct segmentation of fringe pattern obtained from wrapped phase fields is essential to the aim of assigning at each pixel of a fringe the right value of integer 2pi-multiples. In this paper the authors show that interferograms at adjacent frequencies can be combined in order to improve the edge detection among interferometrical fringes in areas affected by different kind of phase ambiguities, thus widening the extension of segmented areas.

This study examines the relationship between temperature and chlorophyll-a in the Gulf of Manfredonia, a coastal zone on the Italian side of the Adriatic Sea. During May 2003, images of [chl-a] and sea surface temperature of the test area have been collected by SeaWiFS and MODIS spectroradiometers. MODIS case2-3band algorithm and SST4 algorithm derived values matched well to the measures obtained from ship surveys. Multivariate statistical measures were computed to determine how MODIS derived pigment and sea surface temperature distributions covaried in the Gulf of Manfredonia. All (except on 16th May) couples of [chl-a] and temperature images with a number of pixels greater than a threshold of around 5000 have a positive correlation coefficient R-CT. These greater images are more suitable to study the correlation, because they have a better geometric resolution and for each pixel is smaller the loose of punctual information.

In SAR interferometry a new approach to height retrieval has been defined, with the aim to obtain the elevation of selected targets in the scene without performing phase unwrapping procedures in the space domain. Following our preliminary simulations, in the paper the results of a first experimentation of this approach with actual SAR data will be introduced.