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The purpose of the study is to assess the suitability of synthetic aperture radar (SAR) data to provide sea surface wind (SSW) fields along with a spatial distribution of both SSW speed and direction uncertainty. A simple methodology based on geophysical model function (GMF) inversion to obtain a spatial distribution of both SSW speed and its uncertainty is proposed. Exploiting a dataset of Sentinel-1 images, a sensitivity analysis of the SSW speed uncertainty is carried out on both the uncertainties and the mean values of SAR normalised radar cross section (NRCS), incidence angle and SSW direction, at different spatial scales. The results show that SSW speed uncertainty significantly increases with wind vector cell (WVC) dimension. Moreover, the dominant contribution to the SSW speed uncertainty due to both NRCS and SSW direction uncertainty must always be taken into account. A better precision and accuracy in the estimation of SSW speed and its uncertainty is evidenced by C-band model 7 (CMOD7) GMF rather than the C-band model 5.N (CMOD5.N). To evaluate the results of SSW retrievals, wind data from the European Centre for Medium-Range Weather Forecasts (ECMWF) model are also exploited for comparisons. Findings indicate a high correlation between the uncertainty from SAR estimations and that from the comparison of SAR vs. ECMWF.

An improved version of the Local-Gradient-Modified (LG-Mod) algorithm for Sea Surface Wind (SSW) directions retrieval by means of Synthetic Aperture Radar (SAR) images is presented. A “local” multi-scale analysis of wind-aligned SAR patterns is introduced to improve the LG-Mod sensitivity to SAR backscattering modulations, occurring locally with various spatial wavelengths. The Marginal Error parameter is redefined, and the adoption of the Directional Accuracy Maximization Criterion (DAMC) allows for the novel Multi-Scale (MS) LG-Mod to automatically select the local processing scale that may be regarded as optimal for pattern enhancement, once a discrete set of scales has been already fixed. Hence, this optimal scale successfully gives evidence to guarantee the best achievable local direction estimation. The assessment of the MS LG-Mod is carried on both simulated SAR images and a Sentinel-1 (S-1) dataset, consisting of 350 Interferometric Wide Swath Ground Range Multi-Look Detected High-Resolution images, which cover the region of the Gulf of Maine. In the latter case, the removal of artifacts and non-wind features from SAR amplitudes is mandatory before directional estimations. In situ wind observations gathered by the National Oceanic and Atmospheric Administration National Data Buoy Center (NOAA NDBC) are exploited for validation. The findings obtained from S-1 data confirm the ones from simulated patterns. The MS LG-Mod analysis performs better than each single-scale one in terms of both percentages of reliable directions and directional Root Mean Square Error (RMSE) values achieved.

Snow cover plays an important role in biotic and abiotic environmental processes, as well as human activities, on both regional and global scales. Due to the difficulty of in situ data collection in vast and inaccessible areas, the use of optical satellite imagery represents a useful support for snow cover mapping. At present, several operational snow cover algorithms and products are available. Even though most of them offer an up-to-daily time scale, they do not provide sufficient spatial resolution for studies requiring high spatial detail. By contrast, the Let-It-Snow (LIS) algorithm can produce high-resolution snow cover maps, based on the use of both the normalized-difference snow index (NDSI) and a digital elevation model. The latter is introduced to define a threshold value on the altitude, below which the presence of snow is excluded. In this study, we revised the LIS algorithm by introducing a new parameter, based on a threshold in the shortwave infrared (SWIR) band, and by modifying the overall algorithm workflow, such that the cloud mask selection can be used as an input. The revised algorithm has been applied to a case study in Gran Paradiso National Park. Unlike previous studies, we also compared the performance of both the original and the modified algorithms in the presence of cloud cover, in order to evaluate their effectiveness in discriminating between snow and clouds. Ground data collected by meteorological stations equipped with both snow gauges and solarimeters were used for validation purposes. The changes introduced in the revised algorithm can improve upon the overall classification accuracy obtained by the original LIS algorithm (i.e., up to 89.17 from 80.88%). The producer’s and user’s accuracy values obtained by the modified algorithm (89.12 and 95.03%, respectively) were larger than those obtained by the original algorithm (76.68 and 93.67%, respectively), thus providing a more accurate snow cover map.

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.

Background The epidemiology of paraneoplastic neurological syndromes (PNS) remains to be defined. We present here the first population-based incidence study and report the clinical spectrum and antibody profile of PNS in a large area in Northeastern Italy. Methods We performed a 9-year (2009–2017) population-based epidemiological study of PNS in the provinces of Udine, Pordenone and Gorizia, in the Friuli-Venezia Giulia region (983,190 people as of January 1, 2017). PNS diagnosis and subgroups were defined by the 2004 diagnostic criteria. Age- and sex-adjusted incidence rates were calculated. Results We identified 89 patients with a diagnosis of definite PNS. Median age was 68 years (range 26–90), 52% were female. The incidence of PNS was 0.89/100,000 person-years. PNS incidence rates increased over time from 0.62/100,000 person-years (2009–2011), 0.81/100,000 person-years (2012–2014) to 1.22/100,000 person-years (2015–2017). The prevalence of PNS was 4.37 per 100,000. Most common PNS were limbic encephalitis (31%), cerebellar degeneration (28%) and encephalomyelitis (20%). Among antibody (Ab)-positive cases, most frequent specificities included: Yo (30%), Hu (26%), and Ma2 (22%), while the most frequent associated tumors were lung (17%) and breast cancer (16%), followed by lymphoma (12%). PNS developed in 1 in every 334 cancers in our region. Statistically significant associations were observed between cancer type and Ab-specificity ( P  < 0.001), and between neurological syndrome and Ab-specificity ( P  < 0.001). Conclusions This first population-based study found an incidence of PNS that approximates 1/100,000 person-years and a prevalence of 4/100,000. Moreover, the incidence of PNS is increasing over time, probably due to increased awareness and improved detection techniques.

Recent clinical trials demonstrated that mechanical thrombectomy (MT) using second-generation endovascular devices has beneficial effects in acute ischemic stroke (AIS) due to large vessel occlusion (LVO). However, it remains controversial if intravenous thrombolysis (IVT) prior to MT is superior compared to direct mechanical thrombectomy (DMT). The aims of this study were to compare short and long-term outcomes between IVT + MT and DMT patients. We prospectively recruited AIS patients with LVO in the anterior or posterior circulation eligible for MT with and without prior IVT. Modified Rankin Scale (mRS) and mortality were assessed at baseline, at discharge, 90-days and 1-year after stroke. Favorable outcome was defined as a mRS score ≤2. Of the 66 patients included, 33 (50%) were in IVT + MT group and 33 (50%) were in DMT group. Except for a higher prevalence of patients using anticoagulants at admission in DMT group, baseline characteristics did not differ in the two groups. Procedural characteristics were similar in IVT + MT and DMT group. Rate of favorable outcome was significantly higher in IVT + MT patients than DMT ones both 90-days (51.5 vs. 18.2%; p = 0.004) and 1-year (51.5 vs. 15.2%; p = 0.002) after stroke. DMT patients were six times more likely to die during the 1-year follow-up compared to IVT + MT patients. This study suggests that bridging therapy may improve short and long-term outcomes in patients eligible for endovascular treatment. Further studies with larger patient numbers and randomized design are needed to confirm our findings.

The CHA2DS2–VASc score is a validated tool to assess the thromboembolic risk in patients with atrial fibrillation. Pre-stroke CHA2DS2–VASc score may predict outcome in patients with acute ischemic stroke (AIS) without atrial fibrillation. The aim of this study was to investigate if the pre-stroke CHA2DS2–VASc score is able to predict short- and long-term outcomes in AIS patients treated with intravenous thrombolysis (IVT). The study group consisted of 256 consecutive patients admitted to the Udine University Hospital with AIS and underwent IVT between January 2015 to March 2017. The pre-stroke CHA2DS2–VASc score for each patient was calculated from the collected baseline data. Patients were classified into three groups according to their pre-stroke CHA2DS2–VASc score: a score of 0 of 1, a score of 2 or 3 and a score above 3. Primary outcome measures were: rate of favorable outcome at 90-days and at 1-year, and mortality at 90-days and at 1-year. Data on functional outcome and mortality 1 year after stroke were collected in 165 patients (65% of the entire sample). Favorable outcome was defined as a modified Rankin Scale score ≤ 2. Compared with the CHA2DS2–VASc score 0–1 group, patients with higher CHA2DS2–VASc scores had a worse outcome and a higher mortality 3 months and 1 year after stroke. The diagnostic performance of the CHA2DS2–VASc score as judged with AUC-ROC was 0.70 (95% CI, 0.64–0.76; p < 0.001) for favorable outcome at 90-days, 0.78 (95% CI, 0.71–0.85; p < 0.001) for favorable outcome at 1-year, 0.71 (95% CI 0.61–0.79) for mortality at 90-days, 0.73 (95% CI 0.64–0.80; p < 0.001) for mortality at 1-year. Pre-stroke CHA2DS2–VASc score represents a good predictor for short- and long-term outcomes in AIS patients treated with IVT.

BackgroundEfficiency of care chain response and hospital reactivity were and are challenged for stroke acute care management during the pandemic period of coronavirus disease 2019 (COVID-19) in North-Eastern Italy (Veneto, Friuli-Venezia-Giulia, Trentino-Alto-Adige), counting 7,193,880 inhabitants (ISTAT), with consequences in acute treatment for patients with ischemic stroke.MethodsWe conducted a retrospective data collection of patients admitted to stroke units eventually treated with thrombolysis and thrombectomy, ranging from January to May 2020 from the beginning to the end of the main first pandemic period of COVID-19 in Italy. The primary endpoint was the number of patients arriving to these stroke units, and secondary endpoints were the number of thrombolysis and/or thrombectomy. Chi-square analysis was used on all patients; furthermore, patients were divided into two cohorts (pre-lockdown and lockdown periods) and the Kruskal-Wallis test was used to test differences on admission and reperfusive therapies.ResultsIn total, 2536 patients were included in 22 centers. There was a significant decrease of admissions in April compared to January. Furthermore, we observed a significant decrease of thrombectomy during the lockdown period, while thrombolysis rate was unaffected in the same interval across all centers.ConclusionsOur study confirmed a decrease in admission rate of stroke patients in a large area of northern Italy during the lockdown period, especially during the first dramatic phase. Overall, there was no decrease in thrombolysis rate, confirming an effect of emergency care system for stroke patients. Instead, the significant decrease in thrombectomy rate during lockdown addresses some considerations of local and regional stroke networks during COVID-19 pandemic evolution.

This study aimed to investigate lymphocyte populations in non-diabetic patients with early clinical presentation of coronary heart disease (CHD). Twenty-five consecutive middle-aged (<55 years) out-patients with CHD (acute myocardial infarction in the previous 3 months) and stable clinical conditions (>1 month) underwent venous blood sampling in order to determinate CD3 + (T-lymphocytes), CD19 + (B-lymphocytes), CD4 + (helper/inducer lymphocytes) and CD8 + (suppressor/cytotoxic lymphocytes) populations. Patients with diabetes, heart failure symptoms, recent revascularization (<30 days) were excluded. Twenty-five patients matched for age, gender and risk factors were enrolled as controls. All patients with CHD previously underwent coronary angiography. CHD patients showed lower CD3 + levels (70.96 ± 4.72 vs. 74.12 ± 4.93 %, p  < 0.05) and CD8 + (37.80 ± 7.15 vs. 46.36 ± 5.22 %, p  < 0.001) but higher CD4 + (37.32 ± 7.99 vs. 31.64 ± 4.72 %, p  < 0.01) and CD4 + /CD8 + ratio (1.06 ± 0.43 vs. 0.69 ± 0.13, p  < 0.001). Difference in CD19 + levels was not statistically significant. Subjects with an impaired (≤55 %) left ventricular ejection fraction were characterized by lower levels of CD8 + (33.23 ± 7.04 vs. 43.76 ± 7.40 %, p  < 0.05) and higher levels of CD4 + (38.31 ± 8.23 vs. 32.73 ± 6.08 %, p  < 0.05) and CD4 + /CD8 + ratio (1.06 ± 0.38 vs. 0.79 ± 0.34, p  < 0.05). CD8 + levels inversely related to severity of coronary atherosclerosis ( r  = −0.37, p  < 0.01). In conclusion, subjects with early clinical presentation of CHD are characterized by an altered CD4 + /CD8 + ratio and lower CD3 + levels.

Kidney transplantation from donors with human immunodeficiency virus (HIV) to recipients with HIV is an emerging practice. It has been performed since 2016 under the U.S. congressional HIV Organ Policy Equity Act and is currently approved for research only. The Department of Health and Human Services is considering expanding the procedure to clinical practice, but data are limited to small case series that did not include donors without HIV as controls. In an observational study conducted at 26 U.S. centers, we compared transplantation of kidneys from deceased donors with HIV and donors without HIV to recipients with HIV. The primary outcome was a safety event (a composite of death from any cause, graft loss, serious adverse event, HIV breakthrough infection, persistent failure of HIV treatment, or opportunistic infection), assessed for noninferiority (margin for the upper bound of the 95% confidence interval, 3.00). Secondary outcomes included overall survival, survival without graft loss, rejection, infection, cancer, and HIV superinfection. We enrolled 408 transplantation candidates, of whom 198 received a kidney from a deceased donor; 99 received a kidney from a donor with HIV and 99 from a donor without HIV. The adjusted hazard ratio for the composite primary outcome was 1.00 (95% confidence interval [CI], 0.73 to 1.38), which showed noninferiority. The following secondary outcomes were similar whether the donor had HIV or not: overall survival at 1 year (94% vs. 95%) and 3 years (85% vs. 87%), survival without graft loss at 1 year (93% vs. 90%) and 3 years (84% vs. 81%), and rejection at 1 year (13% vs. 21%) and 3 years (21% vs. 24%). The incidence of serious adverse events, infections, surgical or vascular complications, and cancer was similar in the groups. The incidence of HIV breakthrough infection was higher among recipients of kidneys from donors with HIV (incidence rate ratio, 3.14; 95%, CI, 1.02 to 9.63), with one potential HIV superinfection among the 58 recipients in this group with sequence data and no persistent failures of HIV treatment. In this observational study of kidney transplantation in persons with HIV, transplantation from donors with HIV appeared to be noninferior to that from donors without HIV. (Funded by the National Institute of Allergy and Infectious Diseases; ClinicalTrials.gov number, NCT03500315.).