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This paper presents the novel estimation algorithm that generates all signals of an object described by nonlinear ordinary differential equations based only on easy-to-implement measurements. Unmeasured signals are estimated by using an adaptive approach. For this purpose, a filtering equation with a continuously modified gain vector is used. Its value is determined by an incremental method, and the amount of correction depends on the current difference between the generated signal and its measured counterpart. In addition, the study takes into account the aging process of measurements and their random absence. The application of the proposed approach can be realized for any objects with a suitable mathematical description. A biochemically polluted river with an appropriate transformation of the notation of partial differential equations was chosen as an object. The results of numerical experiments are promising, and the process of obtaining them involves little computational necessity, so the approach is aimed at the needs of control implemented online. [ABSTRACT FROM AUTHOR]

Introduction: Chronic thromboembolic pulmonary hypertension (CTEPH), characterized by thromboembolic changes affecting the pulmonary bed, leads to ventricular function deterioration and premature death. The introduction of balloon pulmonary angioplasty (BPA) has significantly improved the prognosis of CTEPH patients. Aim: The authors of this article decided to summarize the experience of the BPA program, conducted between 2014 and 2022, at the reference center. Material and methods: Among 111 CTEPH patients, 55 were included in the analysis. A total of 226 sessions were performed, with a significant percentage of intravascular imaging and pressure catheter use. Results: Mean pulmonary pressure decreased significantly from 42 (22–66) to 26.5 mm Hg (11–54) (p < 0.05). Pulmonary vascular resistance and natriuretic peptide concentration decreased from 6.67 (1.66–14) to 3.295 Wood units (1.09–11.11), respectively, and from 1934 (60–16963) to 296 (21–9901) ng/ml (p < 0.05). There was also an improvement in the functional class (WHO) from 2.85 ±0.61 to 2.15 ±0.62 and an increase in the 6-minute walking distance from 300 ±131 to 367 ±154 m (p < 0.05). There were no in-hospital deaths or within 30 days of the procedure. Arterial damage occurred during nine sessions (n = 9/226, 4%), while 0.9% (n = 2/226) were complicated by acute right ventricular failure. Post-reperfusion pulmonary edema (RPE 0 – none) was observed in almost 90% of the sessions, grade 1 to 3 RPE occurred in 10.2%, and grade 4 RPE was not noted. Conclusions: BPA programs conducted in experienced centers are a safe and effective treatment option for inoperable CTEPH patients. [ABSTRACT FROM AUTHOR]

Spinal involvement by chronic non-bacterial osteomyelitis (CNO) has been increasingly reported in recent years, often being presented as a diagnostic dilemma requiring differential diagnosis with bacterial spondylodiscitis and/or neoplasia. This study was aimed at identifying the imaging features of CNO facilitating its differentiation from other spinal diseases. Two radiologists assessed the imaging studies of 45 patients (16 male and 29 female, aged from 6 to 75 years, 15 children) with CNO collected from 5 referential centers. Spinal lesions were found in 17 patients (2 children and 15 adults), most often in the thoracic spine. In children, the lesions involved short segments with a destruction of vertebral bodies. In adults, the main findings were prominent bone marrow edema and osteosclerosis, endplate irregularities, and ankylosing lesions extending over long segments; paraspinal inflammation was mild and abscesses were not observed. In both children and adults, the involvement of posterior elements (costovertebral and facet joints) emerged as an important discriminator between CNO and neoplasia/other inflammatory conditions. In conclusion, a careful inspection of imaging studies may help to reduce the number of biopsies performed in the diagnostic process of CNO. [ABSTRACT FROM AUTHOR]

Glycoalkaloids (GAs) are produced naturally by plants and affect insect survivability and fertility. These compounds can be considered potential bioinsecticides; however, the mechanisms and effects of their action remain undiscovered. As lipids are essential molecules for the proper functioning of an insect organism, this research aimed to determine the effects of GAs on the lipid metabolism of the Tenebrio molitor beetle. Solanine, chaconine, tomatine, and tomato leaf extract were applied to larvae by injection at two concentrations, 10−8 and 10−5 M. Then, the tissue was isolated after 2 and 24 h to determine the levels of free fatty acids, sterols and esters using the GC–MS technique. Moreover, the triacylglyceride level and the activity of the key β-oxidation enzyme, 3-hydroxyacyl-CoA dehydrogenase (HADH), were measured. The results indicate that GAs affect the content and composition of lipid compounds in the beetles' haemolymph and fat body. The effects depend on the GA concentrations, incubation time, and kind of tissue. Moreover, the tested compounds decrease HADH activity, especially in the fat body, which may affect energy production. To our knowledge, this is the first study concerning lipid metabolism in T. molitor after GA application. Our results provide some insights into that topic. [ABSTRACT FROM AUTHOR]

The presented systems with magnetically coupled windings are solved with the finite element method. If the issue of voltage supply is analyzed, a system of linear equations with a partially skew-symmetric sparse matrix is obtained. Iterative methods used to solve a system of equations are particularly effective for symmetric matrices. Resultant equations can be reduced to this symmetrical form by using the method known from the literature [1]. The ratio of the maximum to the minimum eigenvalue of the main matrix of this circuit, which is the condition number, is however very high. This means that the problem is ill-conditioned and leads to a very long iterative solution process. The method presented in the article allows for a direct solution of a system of equations on its part, corresponding to high eigenvalues of the system matrix. The remaining part of the system of equations is solved by iterative methods. This part has much better condition number, and therefore the computational process is fast. The proposed iterative process depends on multiplication of a sparse matrix by vectors. It is not necessary (and possible) to store the entire matrix. This is especially important for larger sizes of a matrix.

In this paper the MTPA, MTPF, constant torque and constant flux control trajectories are presented. These trajectories are calculated for a 6-phase asymmetric insettype SMPMSM generator with the assumption of a certain level of 3rd harmonic current injection. This injection technique increases the generator performance due to the cooperation of the fundamental and 3rd harmonic. The presented trajectories are used for fast control of the generator working in the gearless wind turbine system.

In this paper a system of a grid side and a generator side converters, both working with a common capacitor, is presented. The 6-phase asymmetric inset-type SMPMSM generator is used. A large pole pair number of this generator enables a gearless wind turbine operation. The fundamental and 3rd harmonic cooperation is used to increase the generator performance. This is accomplished by means of the 3rd harmonic current injection. For that reason the generator side converter must have a neutral connection.