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The use of image velocimetry techniques for river monitoring has been increasing in the last few years, but there are some limitations to be solved related mainly to natural environmental conditions and operative framework (Dal Sasso et al., 2021). Along with these issues, the need for surface tracking features or homogeneously distributed materials across the cross-section represents one of the challenges for outdoor applications. In a natural environment, flows can present low seeding densities or locally distributed tracer clusters. These conditions can introduce a high variance and underestimate the flow velocity field, especially near the riverbanks. In this work, the Farnebäck dense optical flow method (Farnebäck 2003) implemented in SSIMS-Flow software (Ljubicic, 2022) was tested and compared with LSPIV technique (Thielicke et al., 2021) to estimate surface flow velocities under different seeding conditions. The application was carried out on the Arrow River (UK) along two meandering river reaches during low-flow conditions. Four different seeding conditions were experimented from low (natural) to high (artificial) seeding density of tracers . Tracers were manually distributed onto the water surface and videos were acquired from DJI Phantom 4 Pro. Seeding metrics were used to estimate seeding conditions including: mean tracer area, seeding density, spatial tracer distribution, and the SDI index (Pizarro et al., 2020). Conventional velocity measurements were used as benchmark purposes along various transects. This study highlighted the good performances of the two tested image velocimetry methods, with results comparable to traditional techniques. On the one hand, the Farnebäck optical flow method proved to be more sensitive to changing setting parameters (e.g., feature extraction rate) with respect to LSPIV. On the other hand, optical flow showed low sensitivity to seeding density (error reduction 30-40%). This is due to the capacity of the Farnebäck method integrated with an ad-hoc pooling technique for spatial velocity averaging to represent surface velocity under sporadic and uneven seeding (e.g., near the convex bank). References Dal Sasso, S. F., Pizarro, A., Manfreda S. (2021). Recent Advancements and Perspectives in UAS-Based Image Velocimetry. Drones 5, 3: 81. Farnebäck, G. (2003). Two-frame motion estimation based on polynomial expansion, Scandinavian conference on Image analysis. Springer, Berlin, Heidelberg. Ljubicic, R. (2022). SSIMS-Flow: UAV image velocimetry workbench, https://github.com/ljubicicrobert/SSIMS-Flow Pizarro, A., Dal Sasso, S.F., Manfreda, S. (2020). Refining image-velocimetry performances for streamflow monitoring: Seeding metrics to errors minimization. Hydrol. Process. 2020, 34, 5167–5175. Thielicke, W., Sonntag, R. (2021). Particle Image Velocimetry for MATLAB: Accuracy and Enhanced Algorithms in PIVlab. Journal of Open Research Software, 9, Ubiquity Press, 2021.

Soil moisture (SM) is an essential element in the hydrological cycle influencing land-atmosphere interactions and rainfall-runoff processes. Quantification of the spatial and temporal behaviour of SM at field scale is vital for understanding water availability in agriculture, ecosystems research, river basin hydrology and water resources management. Uncrewed Arial Systems (UAS) offer an extraordinary opportunity to bridge the existing gap between point-scale field observations and satellite remote sensing providing high spatial details at relatively low costs. Moreover, UAS data can help the construction of downscaling models which can link the land surface features and SM to identify the importance level of each predictor. To optimize the usage of data from UAS surveys for generating high-resolution SM at field scale, a comparative study of various SM retrieval or downscaling methods can be beneficial.In this study, four methods, which include the apparent thermal inertia method, Kubelka–Munk method (KM), simplified temperature-vegetation triangle method, and random forest model (RF), were compared by theory background, data requirements, operation procedures and SM estimation results. The above-mentioned models have been tested using UAS data and point measurements collected on the Monteforte Cilento site (MFC2) in the Alento river basin (Campania, Italy) which is an 8 hectares cropland area (covered by walnuts, cherry, and olive trees). A number of long-term studies on the vadose zone have been conducted across a range of spatial scales. The thermal inertia model is built upon the dependence of the thermal diffusion on SM, which were inferred from diachronic thermal infrared data. The Kubelka–Munk Model is a spectral model to retrieve surface SM using optical data. The simplified temperature–vegetation triangle model, was used to map surface SM based on simultaneous information of the vegetation coverage and surface temperature. In addition, we also introduce an SM downscaling method using the RF model and SENTINEL-1 CSAR 1km SM product.The study is concluded with the inter-comparison of methods. The results from KM have the highest resolution which is the same as the input multispectral data. The results of RF and KM provides information only for bare soil pixels according to the principle of the model. Results show good performances for all methods, but the simplified triangle and thermal inertia model provides better performances in terms of correlation coefficient and RMSE measured with respect to in-situ measurements. In addition, it is worthy to say that the RF downscaling method reveals the features controlling the spatial distributions of SM at a different scale.This research is a part of EU COST-Action “HARMONIOUS” and waterJPI project “iAqueduct”.

Cirrhosis has been long considered a risk factor for bleeding due to the co-existence of the so-called ‘coagulopathy’. More recently, however, compelling evidences have been provided on the occurrence of thrombotic events in the portal and systemic circulation.3–5 Portal vein thrombosis (PVT) is predominantly observed in patients with moderate to severe liver failure with a variable prevalence ranging from 0.6 to 25%. Only fewstudies have provided a longitudinal assessment of the PVT incidence and its sequelae, including recurrence and survival.9–14 Due to the variability of PVT incidence and the paucity of data regarding recurrence and survival,15–20 we prospectively analysed the incidence and the recurrence of PVT in the population of Portal vein thrombosis Relevance On Liver cirrhosis: ItalianVenous thromboticEventsRegistry (PROLIVER), a multi-centre study,8 which involved 43 enrolling centres in Italy (ClinicalTrials.gov Identifier: NCT01470547).

To assess the potential role of ticks as carriers of West Nile virus (WNV) and Usutu virus (USUV), we tested 1721 ticks from 379 wild birds in Northwestern Italy between 2012 and 2014. Ticks were analyzed in pools using a pan-flavivirus real-time RT-PCR and positive pools were subjected to RT-PCR for USUV and WNV genome detection. All the tested samples resulted negative, suggesting that Ixodes spp. ticks, at least in our study area, are not competent vectors and not even exploitable sentinels for USUV and WNV.

We report the preparations and electron spin resonance (ESR) studies of a series of Cs + and Rb + crown ether (15-crown-5 and 18-crown-6) salts of [TcNCl 4 ] - and [MoOCl 4 ] - , and a new refinement of the X-ray structure of [Cs(18-crown-6)] [TcNCl 4 ] involving a twinned P4/n scattering model. This refinement addresses some unsatisfactory aspects of the original disordered model. The structure consists of an ‘infinite sandwich’ Cs + cation/crown ether configuration and polymeric [TcNCL 4 ] - anions, with Tc≡N distances of 1.561(36) Å, and anti-parallel chains of –––Tc≡N–––Tc≡N –––with Tc···Tc separations of 4.275(4) Å. The structure determination of [Rb(15-crown-5) 2 ][TcNCl 4 (OH 2 )] is also described and shows a lattice containing 2:1 ‘sandwich’-type crown ether/alkali-metal cations and isolated anions in the disordered lattice. The presence of Tc≡N infrared stretching frequencies at ca . 1074 cm -1 indicates the absence of strong electron donors coordinated to Tc in the sixth position (i. e. isolated anions), whereas the polymeric chain structure of [Cs(18-crown-6)] [TcNCL 4 ] is characterized by a Tc≡N stretching frequency of 1041 cm -1 . Three product compounds, the ‘infinite sandwich’ [Cs(18-crown6)][TcNCl 4 ], [Cs(18-crown-6)] [TcNCL 4 (OH 2 )] with two Tc≡N stretching frequencies at 1055 and 1046.5 cm -1 , and [Cs(18-crown-6) 2 ][TcNCl 4 containing 2:1 crown ether/Cs + ‘sand­wich’ cations and isolated [TcNCl 4 ] - anions, could be obtained from reaction of Cs + /18-crown-6 and [TcNCL 4 ] - depending on reaction conditions and solvent. The ESR spectra of [Cs(18-crown-6)] [TcNCl 4 ] over the temperature range 130-290 K indicate the presence of exchange interactions along the linear ––– Tc≡N––– Tc≡N––– chains. Spectra for other crown ether salts are consistent with isolated [TcNCL 4 ] - or [TcNCL 4 (OH 2 )] - anions, with dipolar broadening effects apparent.

The annual per caput effective dose and the genetically significant dose to the Australian population, arising from the practice of nuclear medicine, were estimated from the results of a survey of all major hospitals. The survey was conducted for a 4-wk time period during June-July 1991. Patients were characterized by age and gender. The use of diagnostic radiopharmaceuticals resulted in values of 64 microSv and 26 microSv per caput for effective dose and the genetically significant dose, respectively. The effective dose has shown a marked increase in the last decade. These values may be compared to the estimated 2 mSv from natural background radiation.

The di-µ-oxo technetium(VI) complexes [{TcN(S2CNEt2)}2(µ-O)2]1, [{TcN(S2CNC4H8)}2(µ-O)2]2, [AsPh4]2[{TcN(CN)2}2(µ-O)2]4 and [AsPh4]2[{TcN(edt)}2(µ-O)2]5(H2edt = ethane-1,2-dithiol) have been prepared either by reaction of [{TcN(OH2)3}2(µ-O)2]2+ or Cs2[TcNCl5] in Na4P2O7 solution with the appropriate ligand. The ESR spectra of solutions of 1 and 2 in SOCl2 and of 4 in MeCN with added AsPh4Cl·HCl showed that cleavage of the dimer occurs to give the nitridotechnetium(VI) monomers [TcNCl2(S2CNR2)](R = Et or R2= C4H8) or [TcNCl2(CN)2]–. Reaction of [TcVINCl2(S2CNEt2)] with K2[SCOCOS] gave the mixed-ligand complex [AsPh4][TcVN(S2CNEt2)(SCOCOS)]3. Single-crystal X-ray structures (Cu-Kα radiation) were determined for 1, 2 and 3. Complexes 1 and 2 are dimeric and are best described as two edge-sharing square pyramids, with TcN and Tc–Tc distances of 1.623(4), 1.624(4), 2.543(1), and 1.65(2), 1.59(2) and, 2.542(2)A for 1 and 2 respectively. Complex 3 is monomeric with the technetium atom having a square pyramidal geometry, and a TcN distance of 1.54(2)A.

Addition of NEt 4 X to a conc. HX solution of [TcNX 4 (OH 2 )] − (X= Cl or Br) yields crystals of (NEt 4 )[TcNX 4 (OH 2 )] (X=Cl ( 1 ) or Br ( 2 )). Complex 2 crystallises in the orthorhombic space group Pnma with a = 11.366(1), b = 12.930(2), c = 11.540(1) A and Z = 4. Refinement with 1434 data measured with Cu K α radiation converged with R = 0.047. The complex anion has distorted octahedral geometry with a water molecule trans to the nitrido ligand (TcN 1.599(9) and TcOH 2 2.443(7) A). Crystals of Cs 2 [TcNCl 5 ] ( 3 ) belong to the cubic space group Fm m with a = 10.211(1) A and Z = 4. The ligands of the complex anion are statistically disordered over six octahedral sites as required by the cubic space group. Refinement based on 78 data measured with Cu Kα radiation, and with a fixed TcN distance of 1.6 A, converged with R = 0.034. In this model Tc is displaced 0.401(3) A from the plane of the cis ligands towards the nitrido ligand with TcCl cis = 2.373(5), TcCl tras = 2.740(5) A.

The Visual Computing Laboratory of ISTI-CNR, Pisa, frequently collaborates with museums and conservators-restorers in the development of new instruments that can be used in cultural heritage preservation, restoration and display. We present a small but interesting case study in which a broken artifact is virtually reconstructed and can be displayed with a user-friendly visualization tool.