Quantification of not-dipolar components of atrial depolarization by principal component analysis of the P-wave

BACKGROUND: Principal component analysis (PCA) of the T-wave has been demonstrated to quantify the dipolar and not-dipolar components of the ventricular activation, the latter reflecting repolarization heterogeneity. Accordingly, the PCA of the P-wave could help in analyzing the heterogeneous propagation of sinus impulses in the atria, which seems to predispose to fibrillation. AIM: The aim of this study is to perform the PCA of the P-wave in patients prone to atrial fibrillation (AF). METHODS: PCA is performed on P-waves extracted by averaging technique from ECG recordings acquired using a 32-lead mapping system (2048 Hz, 24 bit, 0-400 Hz bandwidth). We extracted PCA parameters related to the dipolar and not dipolar components of the P-wave using the first 3 eigenvalues and the cumulative percent of variance explained by the first 3 PCs (explained variance EV). RESULTS AND CONCLUSIONS: We found that the EV associated to the low risk patients is higher than that associated to the high risk patients, and that, correspondingly, the first eigenvalue is significantly lower while the second one is significantly higher in the high risk patients respect to the low risk group. Factor loadings showed that on average all leads contribute to the first principal component

A Systems Biology Strategy on Differential Gene Expression Data Discloses Some Biological Features of Atrial Fibrillation

Atrial fibrillation (AF), the most common cardiac arrhythmia, is associated with extensive structural, contractile, and electrophysiological remodeling. In this manuscript we re-analyzed gene expression data from a microarray experiment on AF patients and control tissues, using a new paradigm based on a posteriori unsupervised strategy in which the discrimination of patients comes out from purely syntactical premises. This paradigm, more adherent to biological reality where genes work in highly connected networks, allowed us to get both a very precise patients/control discrimination and the discovery of cell adhesion/tissue modeling and inflammation processes as the main dimensions of AF

Use of Azolla as a growing medium component in the nursery production of olive trees

Peat is used in olive-tree nurseries as a component in commercial growing media. Environmental and economic pressures are questioning the use of peat as a component of substrates. In order to remain competitive and to satisfy environmental concerns, it is necessary to identify and evaluate possible alternatives to peat. This study involves the use of Azolla filiculoides, as a growing media component in olive nurseries (Olea europaea L.) for containerized plants. Four treatments were established, based on the addition of increasing quantities of Azolla (0%, 25%, 50%, and 100 %). Were determined some physical and chemical properties of media, the growth, the physiological parameters and nutritional state of olive plants. The physical and chemical properties of the media were significantly affected by the Azolla content. Nursery-produced olive plants grown in substrates supplemented by 50 % Azolla displayed linear growth and the total biomass production greater than those of the control medium. The research indicated that Azolla might be suitable substrate component for olive plants grown in containers

Complexity of MRI induced heating on metallic leads: Experimental measurements of 374 configurations

<p>Abstract</p> <p>Background</p> <p>MRI induced heating on PM leads is a very complex issue. The widely varying results described in literature suggest that there are many factors that influence the degree of heating and that not always are adequately addressed by existing testing methods.</p> <p>Methods</p> <p>We present a wide database of experimental measurements of the heating of metallic wires and PM leads in a 1.5 T RF coil. The aim of these measurements is to systematically quantify the contribution of some potential factors involved in the MRI induced heating: the length and the geometric structure of the lead; the implant location within the body and the lead path; the shape of the phantom used to simulate the human trunk and its relative position inside the RF coil.</p> <p>Results</p> <p>We found that the several factors are the primary influence on heating at the tip. Closer locations of the leads to the edge of the phantom and to the edge of the coil produce maximum heating. The lead length is the other crucial factor, whereas the implant area does not seem to have a major role in the induced temperature increase. Also the lead structure and the geometry of the phantom revealed to be elements that can significantly modify the amount of heating.</p> <p>Conclusion</p> <p>Our findings highlight the factors that have significant effects on MRI induced heating of implanted wires and leads. These factors must be taken into account by those who plan to study or model MRI heating of implants. Also our data should help those who wish to develop guidelines for defining safe medical implants for MRI patients. In addition, our database of the entire set of measurements can help those who wish to validate their numerical models of implants that may be exposed to MRI systems.</p

International Winter Wheat nurseries data: Facultative and Winter Wheat Observation Nurseries and International Winter Wheat yield trials for semi-arid and irrigated conditions

This data paper describes the content of 16 datasets collected under the International Winter Wheat Improvement Program (IWWIP), an alliance between Turkey-CIMMYT-ICARDA (TCI), during the 2015–2016, 2016–2017, 2017–2018 and 2018–2019 seasons. Data was collected from the Facultative and Winter Wheat Observation Nursery (FAWWON) and the International Winter Wheat Yield Trials (IWWYT) conducted under semi-arid and irrigated conditions across different countries. Data on all nurseries was collected during the growing season by IWWIP's team and cooperators in their local environments. It was compiled at the end of the wheat season by IWWIP's team. Multi-locational data can be used to select advanced lines that fit to collaborators’ growing environment. The selected germplasm can either be used as a parent in their breeding programs or be released as a variety in their country

MRI-Induced Heating on Patients with Implantable Cardioverter-Defibrillators and Pacemaker: Role of the Lead Structure

Abstract Magnetic Resonance Imaging (MRI

Towards coordinated site monitoring and common strategies for mitigation of Radio Frequency Interference at the Italian radio telescopes

We present a project to implement a national common strategy for the mitigation of the steadily deteriorating Radio Frequency Interference (RFI) situation at the Italian radio telescopes. The project involves the Medicina, Noto, and Sardinia dish antennas and comprised the definition of a coordinated plan for site monitoring as well as the implementation of state-of-the-art hardware and software tools for RFI mitigation. Coordinated monitoring of frequency bands up to 40 GHz has been performed by means of continuous observations and dedicated measurement campaigns with fixed stations and mobile laboratories. Measurements were executed on the frequency bands allocated to the radio astronomy and space research service for shared or exclusive use and on the wider ones employed by the current and under-development receivers at the telescopes. Results of the monitoring campaigns provide a reference scenario useful to evaluate the evolution of the interference situation at the telescopes sites and a case series to test and improve the hardware and software tools we conceived to counteract radio frequency interference. We developed a multi-purpose digital backend for high spectral and time resolution observations over large bandwidths. Observational results demonstrate that the spectrometer robustness and sensitivity enable the efficient detection and analysis of interfering signals in radio astronomical data. A prototype off-line software tool for interference detection and flagging has been also implemented. This package is capable to handle the huge amount of data delivered by the most modern instrumentation on board of the Italian radio telecsopes, like dense focal plane arrays, and its modularity easen the integration of new algorithms and the re-usability in different contexts or telescopes.Comment: 39 pages, 10 Figures and 7 Tables. INAF Technical Report n. 149 (2022). http://hdl.handle.net/20.500.12386/3208

Experimental on-farm trials data of faba bean and wheat intercropping field validation in Lebanon and Morocco

This data paper describes the content of four datasets col- lected by the International Center for Agricultural Research in the Dry Areas (ICARDA) as a partner in the project “Designing InnoVative plant teams for Ecosystem Resilience and agricultural Sustainability (DIVERSify)”with the objec- tive of assessing the feasibility of faba bean-wheat mix- ture in Mediterranean environments under diverse rainfed conditions. Data was collected during the trials conducted in Kfardan-Lebanon during 2017/2018 where 40 faba bean varieties were evaluated as sole and as mixture with 2 wheat cultivars ‘Margherita’ and ‘Miki’ and during 2018/2019 where 40 faba bean varieties and one durum wheat cultivar ‘Margherita’ were evaluated under low rainfall environments. Trials were also conducted in Tal Amara-Lebanon during 2019/2020 where 20 faba bean lines and one durum wheat cultivar ‘Margherita’ were evaluated under high rainfall en- vironments and in Marchouch-Morocco during 2019/2020 where 7 faba bean lines with 3 cultivars and one durum wheat cultivar ‘Margherita’ were evaluated under extremely low rainfall environments. A detailed list of the different bi- ological traits collected for wheat and faba bean is found in the specification table in this article. The Kfardan 2018/ 2019, Tal Amara and Marchouch data is related to the conference paper “Performance of faba bean-wheat mixture under di- verse Mediterranean environments”

Giovanni Sartori e la democrazia della Seconda Repubblica

Il saggio ripercorre e analizza criticamente tutti i passaggi istituzionali della cosiddetta Seconda Repubblica, ossia della peculiare democrazia maggioritaria che si imposta in Italia a partire dal 1994. Tali passaggi sono visti all'interno del pensiero di Giovanni Sartori e in particolare della sua teoria della democrazia. Tale pensiero si è manifestato sia attraverso opere scientifiche sia attraverso una continua attività pubblicistica, in particolare dalle colonne, come editorialista, del Corriere della Sera. Dall'esame di questo pensiero emerge una serrata e continua critica dei caratteri istituzionali della peculiare democrazia maggioritaria all'italiana.The essay traces and critically analyzes all the institutional steps of the so-called Italian Second Republic, that is the peculiar majoritarian democracy that is set in Italy since 1994. These steps are seen within the thoughts of Giovanni Sartori and in particular of his theory of democracy . Such thinking has manifested both through scientific works both through continuous publications, in particular from the columns, as a columnist, of the Corriere della Sera. From an examination of this thinking emerges a close and continuous criticism of the institutional character of the distinctive Italian style majoritarian democracy