Search

The goal of this work is first to include a hysteresis model in the classical equivalent circuit model (ECM) for a battery system and then to improve the estimation of the state of charge (SoC) by applying the Extended Kalman Filter (EKF). The hysteretic behavior of the open circuit voltage (OCV) is modelled with the classical Preisach model used for magnetic materials. The construction of the Preisach operator is made by means of the Everett function identified from experimental data which only involve the charging curves of the battery. Thus, a significant reduction in the time necessary to obtain the measurements is achieved. The model is assessed with some laboratory experiments performed on a lithium-ion battery and the results show that with this procedure hysteresis is very well reproduced, even when interior loops are present. In addition, the use of the EKF allows us to eliminate the measurements noise and ensure the accuracy of SoC estimation. The high computational efficiency and precision of the method, joined to the limited computational resources needed for the numerical implementation, make it particularly suitable for real-time embedded battery management system (BMS) applications. In addition, the proposed methodology is well-adapted to any battery type, independently of the SoC-OCV profile of the hysteresis cycle. [ABSTRACT FROM AUTHOR]

• MRI is the gold standard in rectal cancer staging but presents some limitations. • Understanding anatomical landmarks on MRI is crucial for appropriate tumor staging. • Lymph node involvement in rectal cancer is a key factor in prognosis and treatment. • Risk-based MRI staging in rectal cancer guides tailored therapeutic strategies. • We provide a structured template to facilitate radiology reports. Magnetic resonance imaging (MRI) plays a pivotal role in primary staging of rectal cancer, enabling the determination of appropriate management strategies and prediction of patient outcomes. However, inconsistencies and pitfalls exist in various aspects, including rectal anatomy, MRI protocols and strategies for artifact resolution, as well as in T- and N-staging, all of which limit the diagnostic value of MRI. This narrative and pictorial review offers a comprehensive overview of factors influencing primary staging of rectal cancer and the role of MRI in assessing them. It highlights the significance of the circumferential resection margin and its relationship with the mesorectal fascia, as well as the prognostic role of extramural venous invasion and tumor deposits. Special attention is given to tumors of the lower rectum due to their complex anatomy and the challenges they pose in MRI staging. The review also addresses current controversies in rectal cancer staging and the need for personalized risk stratification. In summary, this review provides valuable insights into the role of MRI in the primary staging of rectal cancer, emphasizing key aspects for accurate assessment to enhance patient outcomes. [ABSTRACT FROM AUTHOR]

Amphibian populations are globally declining at an alarming rate, and infectious diseases are among the main causes of their decline. Two micro-parasites, the fungus Batrachochytrium dendrobatidis (Bd) and the virus Ranavirus (RV) have caused mass mortality of amphibians and population declines. Other, less understood epizootics are caused by macro-parasites, such as Trombiculoidea chiggers. Infection with chiggers can affect frog behavior and survival. Furthermore, synergistic effects of co-infection with both macro and micro-parasites may lead to higher morbidity. To better understand these potential synergies, we investigated the presence and co-infection by chiggers, Bd and RV in the endemic frog Tlalocohyla smithii (T. smithii). Co-infection of Bd, RV, and/or chiggers is expected in habitats that are suitable for their co-occurrence; and if infection with one parasite facilitates infection with the others. On the other hand, co-infection could decrease if these parasites were to differ in their micro-environmental requirements (i.e. niche apportionment). A total of 116 frogs of T. smithii were studied during 2014 and 2016 in three streams within the Chamela-Cuixmala Biosphere Reserve in Jalisco, Mexico. Our results show that 31% of the frogs were infected with Trombiculoidea chiggers (Hannemania sp. and Eutrombicula alfreddugesi); Hannemania prevalence increased with air temperature and decreased in sites with high canopies and with water pH values above 8.5 and below 6.7. Bd prevalence was 2.6%, RV prevalence was 0%, and none of the frogs infected with chiggers were co-infected with Bd. Together, this study suggests that chiggers do not facilitate infection with Bd, as these are apportioned in different micro-habitats. Nevertheless, the statistical power to assure this is low. We recommend further epidemiological monitoring of multiple parasites in different geographical locations in order to provide insight on the true hazards, risks and conservation options for amphibian populations. Image 1 • This is the first report of Hannemania sp. and Eutrombicula alfreddugesi chiggers in Tlalocohyla smithii. • 31% of the frogs (Tlalocohyla smithii) were infected with Hannemania sp. and Eutrombicula alfreddugesi. • Hannemania prevalence rose with air temperature and fell at sites with high canopies and water pH over 8.5 and below 6.7. • Batrachochytrium dendrobatidis prevalence was 2.6% and Ranavirus prevalence was 0%. • None of the frogs infected with chiggers were coinfected with Bd. [ABSTRACT FROM AUTHOR]

This paper presents a novel and efficient methodology to reduce the time needed to reach the steady-state in the finite element simulation of induction machines. More precisely, the work focuses on induction motors with squirrel cage rotor, where sources in the stator coil sides are given in terms of periodic currents. Essentially, the procedure consists in computing suitable initial conditions for the currents in the rotor bars, thus allowing to obtain the steady-state fields of the machine by solving a transient magnetic model in just a few revolutions. Firstly, the mathematical model that simulates the behavior of the machine is introduced. Then, an approximation of this model is developed, from which suitable initial currents are derived by computing the solution in the least-square sense to an overdetermined problem with only two unknowns. Finally, the method is applied to a particular induction machine working under different operating conditions. The results show important computational savings to reach the motor steady-state in comparison with assuming zero initial conditions, which validate the efficiency of the procedure. [ABSTRACT FROM AUTHOR]