Seasonal changes in dry matter yield from Karst pastures as influenced by morphoclimatic features

Pastures are strongly affected by local environmental variables in terms of their species richness, plant composition and herbage production. A multi-site monitoring study was conducted over three years to investigate the influence of morphoclimatic factors on the seasonal variations in dry matter (DM) yield from Karst pastures. Seven sites located on the Italian and Slovenian Karst regions were investigated that differed in terms of their geological and geomorphological features, as well as their soil types. At each site, the daily DM yield (kg ha-1 d-1) was determined using Corral-Fenlon method which permits to simulate herbage utilization from grazing herds. The morphoclimatic features were also analysed, with the aim to evaluate the link between seasonal DM yield and geomorphological and environmental factors. Generalized non-linear mixed models were built to study the observed seasonal variations in DM yield, using day of the year (DOY), growing degree days (GDD), and cumulative rainfall. Furthermore, environmental descriptors were included in the model in order to evaluate their effects on DM yield. The seasonal variations in yield showed two growing periods (spring and late summer), which were described by Gaussian curves. For the spring growing period, the model improved when the interaction between soil granulometry and growing degree days corresponding to the curve peak was taken into account. This confirms the influence of soil type and air temperature on pasture yield. For the late summer growing period, the interaction between the sand classes and the number of rainy days from the beginning of the period to the peak of the curve improved the model. The curve parameters of our models are correlated with environmental descriptors depending on the lithology and particle size of soils. The results are essential for the optimization of pasture management and avoiding degradation due to over- or under-grazing

“Over-SIRIX”: un nuovo metodo per calcolare l’oversizing delle endoprotesi utilizzando “OsiriX Imaging Software”. Esperienza preliminare nell’impiego di “chimney technique” dell’arco aortico

“Over-SIRIX”: a new method to calculate endograft oversizing by using “OsiriX Imaging Software”. Early experience with chimney technique and TEVAR for the aortic arch diseases Stefano Fazzini, Vittorio Alberti, Sonia Ronchey, Eugenia Serrao, Nicola Mangialardi SAN FILIPPO NERI HOSPITAL, ROME, ITALY STUDY AND PURPOSE The aim of this study is to apply the "Over-SIRIX", a new method to measure oversizing for CHIMPS, not a standard formula. The intention is to minimize the maximum risk of type IA endoleaks, often coming from the gutters. METHOD AND SOURCES From 2002 to 2014 were treated 31 patients with CHIMPS for aortic arch. 19 patients with antegrade single chimney were included, and divided in two groups (PRE/POST) with retrospective and prospective study. The method consists in the study of the proximal neck (MPR), exactly at the level of chimney-graft complex, drawing a circle/oval representing the stent and the perimeter of the endoprosthesis in order to eliminate the "gutters". RESULTS: The average ideal oversizing was of 19.57% (11.4% -27%) and Over-SIRIX 13%; the area of the gutters (cut-off:0.75 cm2) decreased from 0.74 to 0.15 (PRE/POST) and the rate of endoleaks from 28.5% to 0% (PRE/POST). The average neck (26 mm) was comparable between the groups PRE/POST (27/23 mm). CONCLUSION: Over-SIRIX appears to be a simple method that can customize oversizing for CHIMPS reducing the risk of endoleak IA, which is related significantly to the presence and size of the gutters

Successful conversion strategy in patient submitted to EVAR demanding open surgery: comparative analysis 1997-2011 vs 2012-2020

: Late open conversion in our center has been reviewed in the past 8 years, comparing 1997-2011 (first period group A) with 2012-2020 (second period group B). A retrospective analysis of patients treated at our centre by standard EVAR for infrarenal aortic aneurysm requiring late open conversion between January 1997 and February 2020 was performed. All stent grafts were implanted according to their current IFU all patients. The data concerning intra and postoperative complications were collected. Post-operative evaluated data include: ICU (Intensive Care Unit) stay, major peri-operative (<30 days) complications, in hospital mortality, length of hospital stay, 30-days mortality, and mid-term outcomes. Between January 2012 and February 2020 (group B), in our institution 8 patients previously treated by stent graft with endoleak underwent open surgery. The incidence of conversions and the 30-day mortality rate were compared with that of previous years, from January 1997 to December 2011 (group A). 481 patients submitted to EVAR in a second part of the analysis have been considered, 8 patients underwent late open conversion (1.7%) (Group B) due to endoleak. Among January 1997 and December 2011 overall 268 EVAR were performed; during this first study period, surgical conversion had been performed in 14 patients (5.2%) (Group A). The average time from EVAR to open conversion was four years (range 12-88 months) in Group B, and it was 30 months (range 1-82 months) in Group A. In most cases, in both group A and group B the proximal aortic cross-clamping were infrarenal. After the emergent procedure in Group B (12.5%), we have observed a death, whereas three patients died in Group A in urgent situations (21.4%). The more frequent indication for open surgery is the Endoleak type 1 and migration in the two considered periods. Adherence with current IFU and the technical progress in endoprosthesis design maintain lower rate incidence. In most cases, open surgery for prostheses that require explantation can be performed with infrarenal clamping. Partial removal of the endoprosthesis in selected cases makes open conversion easier and appears durable. The results are unfair by numerous comorbidities; in both periods, urgent graft removal seems to elevate both mortality and morbidity, compared to elective surgery

Use of the Orbital Atherectomy System in Isolated, Chronic Atherosclerotic Lesions of the Popliteal Artery

The treatment of isolated calcified lesions involving the popliteal artery are demanding and they often require stent placement to achieve acceptable luminal gain. This study evaluates the safety and performance of the orbital atherectomy system (Cardiovascular Systems Inc.) and percutaneous transluminal angioplasty with a drug-coated balloon (PTA-DCB) for the treatment of chronic atherosclerotic lesions within the popliteal artery segment. From November 2018 to November 2019, a series of six patients with Rutherford classification stage III peripheral arterial disease with isolated, focal, calcified occlusions of the popliteal artery were treated with orbital atherectomy followed by PTA-DCB. No embolic protection devices were used. The technical success rate was 100%, the primary patency rate was 100% at 7.0 (±4.2) months of follow-up. The Rutherford classification improved in all patients from stage III to stage II and the mean ankle brachial pressure index after the procedure was 0.97 (±0.08), with a preoperative mean ankle brachial pressure index of 0.69 (±0.21). In one instance, spasm was noted in a distal arterial bed and it was successfully treated with local nitroglycerine. No distal embolisation, perforation or aneurysmal degeneration was observed. During follow-up there were no deaths, major amputations or revascularisation of target lesions. The use of orbital atherectomy system in combination with PTA-DCB was found to be safe and effective in modifying focal, chronic, calcified plaques in the popliteal artery segment in these six cases

Endovascular Management of Juxtarenal and Pararenal Abdominal Aortic Aneurysms: Role of Chimney Technique

The use of chimney technique in endovascular repair of abdominal aortic aneurysms (ChEVAR) has had a secondary role. Although it was first developed in an emergent/urgent setting, the publication of various important studies has helped overcome scepticism towards this technique in elective procedures. This paper reviews current evidence about ChEVAR, focusing on clinical results, technical notes and comparisons with other techniques. The new ChEVAR findings show favourable mid- and long-term clinical outcomes, even in elective patients. These results, comparable to those related to fenestrated endografts, have been achieved through standardisation in planning and materials. An adequate endograft oversizing associated to the right aortic neck length is fundamental to avoid ChEVAR-related complications, such as type 1a endoleaks. These data indicate that ChEVAR, compared to other complex endovascular treatments, has comparable outcomes along with features that could make it an essential option in every clinical setting

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file