213 research outputs found

    Assessment of an adjustment factor to model radar range dependent error

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    Quantitative radar precipitation estimates are affected by errors determined by many causes such as radar miscalibration, range degradation, attenuation, ground clutter, variability of Z-R relation, variability of drop size distribution, vertical air motion, anomalous propagation and beam-blocking. Range degradation ( including beam broadening and sampling of precipitation at an increasing altitude) and signal attenuation, determine a range dependent behavior of error. The aim of this work is to model the range-dependent error through an adjustment factor derived from the G/R ratio trend against the range, where G and R are the corresponding rain gauge and radar rainfall amounts computed at each rain gauge location. Since range degradation and signal attenuation effects are negligible close to the radar, resultsshowthatwithin 40 km from radar the overall range error is independent of the distance from Polar 55C and no range-correction is needed. Nevertheless, up to this distance, the G/R ratiocan showa concave trend with the range, which is due to the melting layer interception by the radar beam during stratiform events

    On precipitation measurements collected by a weather radar and a rain gauge network

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    Many phenomena (such as attenuation and range degradation) can influence the accuracy of rainfall radar estimates. They introduce errors that increase as the distance from radar increases, thereby decreasing the reliability of radar estimates for applications that require quantitative precipitation estimation. The present paper evaluates radar error as a function of the range, in order to correct the rainfall radar estimates. The radar is calibrated utilizing data from the rain gauges. Then, the G/R ratio between the yearly rainfall amount measured in each rain gauge position during 2008 and the corresponding radar rainfall amount is calculated against the slant range. The trend of the G/R ratio shows two behaviours: a concave part due to the melting layer effect close to the radar location and an almost linear, increasing trend at greater distances. A best fitting line is used to find an adjustment factor, which estimates the radar error at a given range. The effectiveness of the methodology is verified by comparing pairs of rainfall time series that are observed simultaneously by collocated rain gauges and radar. Furthermore, the variability of the adjustment factor is investigated at the scale of event, both for convective and stratiform events. The main result is that there is not a univocal range error pattern, as it also depends on the characteristics of the considered event. On the other hand, the adjustment factor tends to stabilize itself for time aggregations of the order of one year or greater

    A non-hydrolytic sol-gel approach for the preparation of MgxAl2(1-x)Ti(1+x)O5 powders

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    The study of non-hydrolytic reactions for the synthesis of MgxAl2(1-x)Ti(1+x)O5 solid solution with x = 0.6 is reported. The reagents chosen were Al(OsBu)(3), Ti(OiPr)(4), TiCl4 and Mg(NO3)(2).6H(2)O in toluene. The reactions were followed using C-13 Nuclear Magnetic Resonance (NMR) spectroscopy. Sol-gel synthesized powders were calcined in air at 300, 500, 1000, and 1200degreesC for 1 h. The powders were analysed by X-Ray Diffraction (XRD) demonstrating the formation of a Mg0.6Al0.8Ti1.6O5 phase in samples treated at the higher calcination temperature

    Data selection to assess bias in rainfall radar estimates. An entropy-based method

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    Miscalibration of radar determines a systematic error (i.e., bias) that is observed in radar estimates of rainfall. Although a rain gauge can provide a pointwise rainfall measurement, weather radar can cover an extended area. To compare the two measurements, it is necessary to individuate the weather radar measurements at the same location as the rain gauge. Bias is measured as the ratio between cumulative rain gauge measurements and the corresponding radar estimates. The rainfall is usually cumulated, taking into account all rainfall events registered in the target area. The contribution of this work is the determination of the optimal number of rainfall events that are necessary to calibrate rainfall radar. The proposed methodology is based on the entropy concept. In particular, the optimal number of events must fulfil two conditions, namely, maximisation of information content and minimisation of redundant information. To verify the methodology, the bias values are estimated with 1) a reduced number of events and 2) all available data. The proposed approach is tested on the Polar 55C weather radar located in the borough area of Rome (IT). The radar is calibrated against rainfall measurements of a couple of rain gauges placed in the Roman city centre. Analysing the information content of all data, it is found that it is possible to reduce the number of rainfall events without losing information in evaluating the bias

    New Insight on Medieval Painting in Sicily: The Virgin Hodegetria Panel in Monreale Cathedral (Palermo, Italy)

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    : The Virgin Hodegetria, located in the Cathedral of Santa Maria Nuova in Monreale, near Palermo (Italy), probably dating the first half of the 13th century, is one of the earliest examples of medieval panel painting in Sicily. A diagnostic campaign was carried out on the panel aiming to identify the constituting materials and the executive technique, as well as to assess the state of conservation for supporting the methodological choice of the restoration intervention. Both non invasive (X-ray radiography, digital microscope, multispectral imaging, ED-X-ray fluorescence) and micro-invasive (polarised light microscopy, ESEM-EDX, ATR-FTIR spectroscopy and micro-Raman spectroscopy) analyses were performed. According to the results, the executive technique followed the 13th–14th-century Italian painting tradition. A complex structure was applied on the wooden support, consisting of a double layer of canvas and several ground layers of gypsum and glue based binder. The underdrawing was made by a brush using carbonaceous black pigment. The original palette includes red ochre, red lead, azurite, carbon black and bone black. During the several restorations, mercury-based red, indigo, smalt blue, orpiment and synthetic mars were used. The original silver leaf of the frame was covered with red tin-based lake and subsequently regilded with gold leaf. Proteinaceous and oil binders were also detecte

    CAN METABOLIC SYNDROME AFFECT THE EFFICACY OUTCOMES OF COMBINATION THERAPY WITH DAILY TADALAFIL 5MG PLUS TAMSULOSIN 0.4MG IN MEN WITH LUTS AND ED?

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    INTRODUCTION AND OBJECTIVE: Metabolic Syndrome (METS) has a high prevalence (26.5%–55.6%) in men with LUTS and erectile dysfunction (ED). Daily tadalafil 5mg intake is currently recognized as an effective pharmacological treatment for male LUTS, alone or in combination with alpha-lithics such as tamsulosin 0,4mg, ensuring a greater LUTS relieve. Aim of this study is to assess if METS could affect the efficacy of combination therapy with daily tadalafil 5mg plus tamsulosin 0,4mg in men with LUTS and ED. METHODS: Across 12 months, fifty consecutive patients aged >40 to 80 years, with moderate to severe LUTS (IPSS >7) and mild to severe ED (IIEF-5 <22) were enrolled and treated with the previous combination therapy for 12 weeks. The assessment of patients included age, body mass index (BMI), METS features - waist circumference (WC), blood pressure, clinical laboratory parameters- digital rectal examination, IPSS, OABq, uroflowmetry and postvoid residual (PVR) volume, IIEF-5. METS was defined according to NCEP ATP III. Differences were calculated by unpaired sample t-test at baseline and 12 weeks. The analysis of variance (ANOVA) was used for between-group differences. RESULTS: Among 50 patients enrolled, 31 (62.0%) had METS. Mean age was similar with 65.5 years (9.1) in patients without METS and 67.1 years (7.2) in METS patients, p=0.133. Baseline IPSS, OAB-q and IPSS QoL were significantly higher in patients with METS (p<0.05), while IIEF was higher in patients without METS (p=0.039) at baseline (Table1). After 3 months of combination therapy, IIEF, total IPSS and subscores, OAB-q and Qmax significantly improved in both groups. DeltaIPSS, deltaQMax and deltaIIEF were similar between groups (p>0.05). However, total IPSS, IPSS QoL, IPSS Voiding and IPSS Storage were significantly better at the end of the trial in men without METS. Conversely, 12wks IIEF was similar in patients with or without METS (16.3 vs 17.7 p=0.238) (Table2). CONCLUSIONS: Tadalafil plus tamsulosin combi therapy represents an effective LUTS treatment in male, independently from METS. Despite a similar improvement of LUTS (delta), patients without METS obtained a significantly better LUTS relieve. Interestingly, the efficacy in ED was greater in men with METS and, at the end of trial, IEEF-5 scores were similar in the two groups

    Esperienze di monitoraggio integrato: il caso della Rete Sismometrica dell’Italia centro orientale e dei suoi servizi

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    Viene presentata l’esperienza maturata dagli operatori della sede di Ancona dell’INGV (INGV-AN) nell’ambito delle collaborazioni tra l’Istituto Nazionale di Geofisica e Vulcanologia (INGV) e la Regione Marche per il miglioramento delle attività di monitoraggio sismico. L’attività dell’INGV-AN aveva due scopi: migliorare le conoscenze sulla sismicità regionale a fini scientifici e perfezionare il servizio di informazione svolto per il Dipartimento per le Politiche Integrate di Sicurezza e per la Protezione Civile (DPISPC). Per il raggiungimento degli scopi si è proceduto all’incremento del numero di stazioni, alla trasformazione in real- time della vecchia rete dial-up, alla installazione di nuove stazioni accelerometriche, e all’utilizzo del complesso dei dati raccolti dalle stazioni accelerometriche e velocimetriche in funzione nel territorio regionale e in quelli immediatamente limitrofi, nonché allo scambio dati tra la sede INGV di Ancona e quella di Roma. I costi dell’intera operazione sono stati contenuti grazie all’utilizzo delle infrastrutture radio wireless della Regione Marche, della economica trasmissione UMTS, di acquisitori GAIA sviluppati dall’INGV e di economici ma efficaci accelerometri MEMS SF3000L della Colybris. Gli obiettivi raggiunti sono i presupposti per il proseguimento della collaborazione tra i due enti rivolta alla copertura più ampia possibile del territorio regionale con reti di rilevamento accelerometrico a basso costo e alla realizzazione di servizi sempre più finalizzati all’emergenza sismica

    Male Lower Urinary Tract Symptoms and Cardiovascular Events: A Systematic Review and Meta-analysis

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    Context The correlation among metabolic syndrome, lower urinary tract symptoms (LUTS), and cardiovascular disease (CVD) is well established. In particular, CVD has been proposed as a potential risk factor for both LUTS progression and severity. Objective To evaluate whether LUTS severity can be considered as a significant risk factor of major adverse cardiac events (MACE) in the male population. Evidence acquisition A systematic literature search was performed using PubMed, Google Scholar, and Scopus. The combination of the following keywords was adopted in a free-text strategy: benign prostatic hyperplasia (BPH) or lower urinary tract symptoms (LUTS) and cardiovascular, cardio, major adverse cardiac events, MACE, heart disease, heart, myocardial infarction, myocardial, infarction, stroke, ischemic events, ischemic, cardiac death, coronary syndrome. We included all cross-sectional and longitudinal trials enrolling men and comparing the prevalence or incidence of MACE in men with moderate to severe LUTS compared with those without LUTS or with mild LUTS. The studies in which only nocturia was evaluated were excluded from the analysis. Evidence synthesis Of 477 retrieved articles, 5 trials longitudinally reported the incidence of MACE in patients with moderate to severe LUTS in comparisons to those with mild or no LUTS and 10 studies reported the prevalence of history of MACE at enrollment. All were included in the present meta-analysis. Among cross-sectional studies, 38 218 patients and 2527 MACE were included in the meta-analysis. The mean age of enrolled patients was 62.2 Â± 8.0 yr. Presence of moderate to severe LUTS significantly increased the risk of reported history of MACE (p < 0.001). Metaregression analyses showed that the risk of MACE was lower in older patients and higher in those with diabetes. The association between LUTS-related MACE and diabetes was confirmed in a multivariate regression model after adjusting for age (adjusted r = 0.498; p < 0.0001). Longitudinal trials included 25 494 patients and 2291 MACE. The mean age of enrolled patients was 52.5 Â± 5.5 yr, and mean follow-up was 86.8 Â± 22.1 mo. Presence of moderate to severe LUTS was associated with an increased incidence of MACE compared with the rest of the sample (odds ratio: 1.68; 95% confidence interval, 1.13–2.50; p = 0.01). Conclusions Men with moderate to severe LUTS seem to have an increased risk of MACE. A holistic approach in considering the morbidities of aging men should be strongly encouraged and represents an important role for the practicing urologist. Patient summary We evaluated whether the severity of lower urinary tract symptoms could be considered as a significant risk factor for major adverse cardiac events (MACE) in the male population. We demonstrated that men with moderate to severe LUTS have an increased risk of MACE
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