Long-term versus short-term deformation processes at Tenerife (Canary Islands)

Several geophysical investigations have identified that the Tenerife volcanic complex is affected by crustal deformation processes occurring at timescales of millions of years. Recently, space-based geodetic observations have also detected a short-term surface deformation, characterized by a broad subsidence pattern with maximum ground velocities of about 4 mm yr−1. For the purpose of investigating the relationship between these long-term and short-term deformation processes, we performed an advanced fluid dynamic analysis (FDA). We first carried out a standard dimensionless FDA to discriminate the deformation style of Tenerife and found that, at million year timescales, basement flexure mainly controls its long-term structural evolution. Secondly, to highlight the driving forces of the short-term deformation process, we simulated a numerical FDA based on finite element models that include topography as well as vertical and lateral material heterogeneities. Our results show that the recent surface deformation is mainly caused by a progressive sagging of the denser (less viscous) core of the island onto the weaker (but more viscous) lithosphere. Moreover, over periods comparable to the hypothesized age of loading of the oceanic crust beneath Tenerife, this tendency would result in a total flexure of about 3–4 km, which is in agreement with independent estimations based on geophysical analyses. Our study shows that a unitary physical model may explain both the deformation recorded in deep geological structures and the current active ground deformation processes occurring at the Tenerife volcano.Peer reviewe

Gravity-driven deformation of Tenerife measured by InSAR time series analysis,

We study the state of deformation of Tenerife (Canary Islands) using Differential Synthetic Aperture Radar Interferometry (DInSAR). We apply the Small BAseline Subset (SBAS) DInSAR algorithm to radar images acquired from 1992 to 2005 by the ERS sensors to determine the deformation rate distribution and the time series for the coherent pixels identified in the island. Our analysis reveals that the summit area of the volcanic edifice is characterized by a rather continuous subsidence extending well beyond Las Cañadas caldera rim and corresponding to the dense core of the island. These results, coupled with GPS ones, structural and geological information and deformation modeling, suggest an interpretation based on the gravitational sinking of the dense core of the island into a weak lithosphere and that the volcanic edifice is in a state of compression. We also detect more localized deformation patterns correlated with water table changes and variations in the deformation time series associated with the seismic crisis in 2004.Peer reviewe

Sources of Resistance to Phytophthora cinnamomi in Juglans spp. for Potential Rootstocks

diverse collection of Juglans species and hybrids with potential to serve as walnut rootstocks was evaluated to identify resistance to Phytophthora cinnamomi, a destructive pathogen affecting commercial production of Persian walnuts worldwide. A total of 35 Juglans genotypes, comprising hybrids and Juglans microcarpa, plus three Juglans regia genotypes as comparison, were inoculated during two seasons (spring and autumn) for 3 years, with two isolates of P. cinnamomi. Inoculations were carried out on excised shoots of the different genotypes by replacing a bark disk with a P. cinnamomi culture plug. After incubation, necrosis length caused by the pathogen was measured. Data were collected and statistically analyzed with generalized linear mixed models. This work pointed out a seasonal influence on some Juglans genotype response to P. cinnamomi: both hybrids and J. microcarpa groups were significantly less sensitive in autumn compared with spring (P = 0.0006), thus this condition must be considered when selecting Juglans for resistance to this pathogen. Three genotypes of J. regia, known for its susceptibility to P. cinnamomi, were used as comparison. Results show good levels of resistance to P. cinnamomi in J. microcarpa genotypes, confirming literature results. Among J. microcarpa genotypes, the Jmi03 is quite promising for its in vitro propagation. A number of Juglans hybrids, H5/18, 7/28,8/29, 10/43, and 6/22, showed significantly higher levels of resistance to P. cinnamomi, compared with susceptible J. regia genotypes. Evaluation, in naturally infected fields, of clonal genotypes and seedlingprogenies of resistant genotypes, grafted with commercial walnut varieties, is currently under way and will provide additional information for successful usage

Sources of Resistance to Phytophthora cinnamomi in Juglans spp. for Potential Rootstocks

diverse collection of Juglans species and hybrids with potential to serve as walnut rootstocks was evaluated to identify resistance to Phytophthora cinnamomi, a destructive pathogen affecting commercial production of Persian walnuts worldwide. A total of 35 Juglans genotypes, comprising hybrids and Juglans microcarpa, plus three Juglans regia genotypes as comparison, were inoculated during two seasons (spring and autumn) for 3 years, with two isolates of P. cinnamomi. Inoculations were carried out on excised shoots of the different genotypes by replacing a bark disk with a P. cinnamomi culture plug. After incubation, necrosis length caused by the pathogen was measured. Data were collected and statistically analyzed with generalized linear mixed models. This work pointed out a seasonal influence on some Juglans genotype response to P. cinnamomi: both hybrids and J. microcarpa groups were significantly less sensitive in autumn compared with spring (P = 0.0006), thus this condition must be considered when selecting Juglans for resistance to this pathogen. Three genotypes of J. regia, known for its susceptibility to P. cinnamomi, were used as comparison. Results show good levels of resistance to P. cinnamomi in J. microcarpa genotypes, confirming literature results. Among J. microcarpa genotypes, the Jmi03 is quite promising for its in vitro propagation. A number of Juglans hybrids, H5/18, 7/28,8/29, 10/43, and 6/22, showed significantly higher levels of resistance to P. cinnamomi, compared with susceptible J. regia genotypes. Evaluation, in naturally infected fields, of clonal genotypes and seedlingprogenies of resistant genotypes, grafted with commercial walnut varieties, is currently under way and will provide additional information for successful usage

Clinical Outcomes of Percutaneous Left-Atrial Appendage Occlusion with Conscious Sedation without an Anesthesiologist on Site: Results from a Multicenter Study

Background and Objectives: Percutaneous left-atrial appendage (LAA) occlusion is an important therapeutic option for preventing cardioembolic stroke in patients with non-valvular atrial fibrillation (AF) at high risk of thromboembolic events and with contraindications for oral anticoagulation (OAC). It is usually performed with transesophageal echocardiography (TOE) guidance under general anesthesia (GA). In this retrospective study, we present a multicenter experience of LAA occlusion performed with conscious sedation (CS) without an anesthesiologist on site. Materials and Methods: All the patients on the waiting list for LAA occlusion procedure at Infermi Hospital, Rivoli, and San Luigi Gonzaga University Hospital, Orbassano, from October 2018 to October 2022 were analyzed. All the procedures were performed with a Watchman/FLX LAA closure device under TOE and fluoroscopic guidance without an anesthesiologist on site. CS was performed with a combination of midazolam and fentanyl as needed. Results: One-hundred fifteen patients were included (age 76.4 ± 7.6 years, median CHA2DS2Vasc 4.4 ± 1.4). CS was performed using midazolam (mean dose 5.9 ± 2.1 mg), adding fentanyl for thirty-nine (33.9%) patients in case of poor tolerance for the procedure despite midazolam. The acute procedural success rate was 99.1%. We observed seven acute severe complications. No patients needed anesthesiological assistance during the procedure, and no cases of respiratory failure necessitating ventilation were reported. In a follow-up after 10 ± 9 months, one case of stroke (0.9%) and one case (0.9%) of transient ischemic attack (TIA) occurred. Conclusions: LAA occlusion performed under CS and without the presence of an anesthesiologist on site appears to be safe and effective. It can be an attractive alternative to general anesthesia (GA), as fewer resources are required

Appropriateness of antiplatelet therapy for primary and secondary cardio- and cerebrovascular prevention in acutely hospitalized older people

Aims: Antiplatelet therapy is recommended for the secondary prevention of cardio- and cerebrovascular disease, but for primary prevention it is advised only in patients at very high risk. With this background, this study aims to assess the appropriateness of antiplatelet therapy in acutely hospitalized older people according to their risk profile. Methods: Data were obtained from the REPOSI register held in Italian and Spanish internal medicine and geriatric wards in 2012 and 2014. Hospitalized patients aged ≥65 assessable at discharge were selected. Appropriateness of the antiplatelet therapy was evaluated according to their primary or secondary cardiovascular prevention profiles. Results: Of 2535 enrolled patients, 2199 were assessable at discharge. Overall 959 (43.6%, 95% CI 41.5–45.7) were prescribed an antiplatelet drug, aspirin being the most frequently chosen. Among patients prescribed for primary prevention, just over half were inappropriately prescribed (52.1%), being mainly overprescribed (155/209 patients, 74.2%). On the other hand, there was also a high rate of inappropriate underprescription in the context of secondary prevention (222/726 patients, 30.6%, 95% CI 27.3–34.0%). Conclusions: This study carried out in acutely hospitalized older people shows a high degree of inappropriate prescription among patients prescribed with antiplatelets for primary prevention, mainly due to overprescription. Further, a large proportion of patients who had had overt cardio- or cerebrovascular disease were underprescribed, in spite of the established benefits of antiplatelet drugs in the context of secondary prevention