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Segmented radial seals are modern technologies used in aeronautic engines and space turbopumps. They consist of several circumferential segments assembled as an annular ring freely mounted on the rotor. A circumferential (garter) spring tightens the segments around the shaft. The segments can move radially relative to each other, sliding against a casing and following the dynamic displacements of the rotor. Two similar segmented seals made of different materials were tested. The results showed different leakage flow rates and different correlations between leakage and wear rate. For example, the leakage rate decreases with wear for one seal and increases for the other. For explaining these results, wear was correlated with the microstructure of the materials of the two seals. Profilometric analyses were made for the two seals, highlighting that wear was not localised in the same areas. Raman spectra maps were taken on the pads of the segment in contact with the rotor and microstructural changes caused by friction were enlightened. The evolution of residual stresses was measured for new and worn segments. These findings strengthen the results obtained from profilometric wear analyses. They also allow a more precise understanding of tribological degradation scenarios depending on the operating conditions and the properties of the material.

Abstract Background The relationship between liver fibrosis and left atrial (LA) remodeling in atrial fibrillation (AF) remains uncertain. We examined the associations between the fibrosis‐4 (FIB4) index, an indicator of liver fibrosis, and both LA low‐voltage areas (LVAs) on electroanatomic mapping and AF recurrence postablation. Methods We recruited 343 patients who underwent radiofrequency catheter ablation (RFCA) or cryoballoon ablation (CBA) for AF. First, the association between the FIB4 index and LA LVAs (5 cm2) compared to those without. Additionally, the quantitative size of LVAs showed a positive correlation with the FIB4 index (R = .642, p

In this work, we investigate a class of generalized affine fractal interpolation functions (FIF) with variable parameters, where ordinate scaling is substituted by a real-valued control function. Let $ {\mathcal S} $ be an iterated function system (IFS) with the attractor $ G_\Delta $, where $ \Delta $ is a given data set. We consider an affine transformation $ \omega(\Delta) $ of $ \Delta $, and we define the IFS $ \hat {\mathcal S} $ with the attractor $ G_{\omega(\Delta)} $. We give a sufficient condition so that $ G_{\omega(\Delta)} = \omega(G_\Delta) $. In addition, we compare the definite integrals of the corresponding FIF and study the additivity property. Some examples will be given, highlighting the effectiveness of our results.

Fractal interpolation function (FIF) is a fixed point of the Read–Bajraktarević operator defined on a suitable function space and is constructed via an iterated function system (IFS). In this paper, we considered the generalized affine FIF generated through the IFS defined by the functions $ W_n(x, y) = \big(a_n(x)+e_n, \alpha_n(x) y +\psi_n(x)\big) $, $ n = 1, \ldots, N $. We studied the shift of the fractal interpolation curve, by computing the error estimate in response to a small perturbation on $ \alpha_n(x) $. In addition, we gave a sufficient condition on the perturbed IFS so that it satisfies the continuity condition. As an application, we computed an upper bound of the maximum range of the perturbed FIF.

Mahasiswa yang kurang terampil dalam public speaking cenderung mengalami kesulitan saat harus melakukan presentasi di kelas. Hal ini bisa berdampak pada penilaian mereka karena presentasi sering kali menjadi bagian penting dari evaluasi akademik. Penelitian ini bertujuan untuk menguji tingkat kemampuan public speaking mahasiswa sebelum dan sesudah diberikan konseling analisis transaksional. Jenis penelitian yang digunakan adalah kuantitatif eksperimen, dengan pendekatan pre-eksperiment one-group pretest and posttest design. Subjek pada penelitian ini adalah mahasiswa Universitas Muhammadiyah Sumatera Barat. Metode pengumpulan data menggunakan angket kemampuan public speaking mahasiswa dengan analisis uji rank bertanda Wilcoxon. Hasil analisis data menunjukkan bahwa terdapat perbedaan antara skor pretest dan posttest yang terlihat dari rata-rata nilai pretest yaitu sebesar 126 dengan kategori sedang dan posttest sebesar 186 dengan kategori tinggi. Dalam hal ini, konseling analisis transaksional efektif meningkatkan kemampuan public speaking mahasiswa Universitas Muhammadiyah Sumatera Barat

Fractal interpolation function (FIF) is a new method of constructing new data points within the range of a discrete set of known data points. Consider the iterated functional system defined through the functions $ W_n(x, y) = \big(a_n x+e_n, \alpha_n(x) y +\psi_n(x)\big) $, $ n = 1, \ldots, N $. Then, we may define the generalized affine FIF $ f $ interpolating a given data set $ \big\{ (x_n, y_n) \in I\times \mathbb R, n = 0, 1, \ldots, N \big\} $, where $ I = [x_0, x_N] $. In this paper, we discuss the smoothness of the FIF $ f $. We prove, in particular, that $ f $ is $ \theta $-hölder function whenever $ \psi_n $ are. Furthermore, we give the appropriate upper bound of the maximum range of FIF in this case.

Linear increase in crystallite size (16–24 nm) of MnxZn1−xFe2O4 nanostructures and mixed behavior of lattice constant (8.429–8.462 Å) is reported. The system exhibits considerable promise for microwave applications due to its elevated dielectric constants and minimal dispersion losses from 20 Hz to 20 MHz. With x = 0.75, sample is good for energy storage devices like supercapacitors due to large specific surface area (53 m2/g) and dielectric constant. These samples exhibit maximum relaxation times ranging from 1.97 × 10−7 s to 2.43 × 10−4 s, with corresponding relaxation energy values spanning from 159.22 meV to 341 meV for x = 0 and x = 1 samples. The Cole-Cole plots reveal that grains exhibit conductive behavior at lower frequencies, while grain boundaries contribute significantly to the resistive behavior. Additionally, we have introduced Bode diagrams and equivalent electronic circuit models for the first time, offering valuable insights into the electrical behavior of the nanomaterial samples.

Clozapine, renowned for its efficacy in treatment-resistant schizophrenia, is associated with rare yet potentially severe side effects, including hematological disorders, myocarditis, seizures and gastrointestinal obstruction. Dermatological adverse effects, though less serious, can profoundly impact patients’ quality of life. We present the first reported case of cholinergic urticaria induced by clozapine, in a 25-year-old male with treatment-resistant schizophrenia. Four months into clozapine therapy, the patient developed intensely pruritic erythematous lesions triggered by sweating, significantly impairing his daily activities. Despite attempts at management, including dose reduction and antihistamine therapy, the urticaria persisted. However, a favorable outcome was achieved upon switching to quetiapine. This case underscores the importance of recognizing and managing treatment-related adverse effects, even when they arise late in treatment, and highlights the need for individualized therapeutic approaches.We discuss potential mechanisms underlying clozapine-induced cholinergic urticaria and emphasize the significance of patient-centered care in optimizing treatment outcomes in schizophrenia.

MRI-guided focused ultrasound (MRgFUS) lesioning is an innovative, safe and effective treatment which provides an innovative development in the field of minimally invasive stereotactic neurosurgery. Based on the application of focused ultrasound energy under full MR planning and thermal imaging control, unilateral lesioning of the thalamus, subthalamic nucleus, and globus pallidus is indicated for the treatment of movement disorders, including essential tremor, Parkinson’s disease, and dystonia. We started to apply this technique in February 2019 for the treatment of patients with movement disorders. The authors developed a diagnostic therapeutic care pathway, which is herewith proposed and applied as an explication of standard clinical practice in use. The project was the result of the application of different methods such as Health Technology Assessment (HTA), Strengths, Weaknesses, Opportunities and Threats analysis (SWOT) and Demin -Plan, Do, Check, Act (PDCA) cycle. The aim of this project was to standardize the MRgFUS diagnostic-therapeutic pathway (DTP), describe its application and the appropriateness of different phases (patient selection, intervention phase and follow-up). Here, we described in detail our experience in the DTP application from 2019 up to now in 610 patients with movement disorders.

Lead is a pollutant that is often found in various locations that may affect the behavior of living things. The purpose of this study was to analyze the effect of lead exposure on behavior changes in Drosophila melanogaster. Flies were grouped into four levels of lead exposure: 0, 100, 150 and 200 ppm for two generations. Behavioral observations were made before and after lead exposure. The observed behavior was the ability of the pupae to climb through the pupa position assay and the success and speed of the imago climbing through the adult climbing assay. As a result, higher exposure to lead tends to increase the percentage of pupae in the low zone. Pupae with tilted orientation always have the highest percentage in all groups, both in generation 0 and generation 2. Furthermore, the results of the analysis of covariance inform that lead exposure have no significant effect on climbing duration and climbing success. Overall, lead exposure has the potential to affect the behavior of D. melanogaster. Further studies involving other behavioral assays need to be conducted to observe the effect of lead on all behavioral variables.

La surexploitation des nappes génère un coût économique et environnemental qui se traduit par la diminution de la disponibilité de l’eau et l’augmentation de son coût de pompage. Les études portant sur la distribution de ces coûts à travers les types d’exploitations et leur impact sur l’équité d’accès aux eaux souterraines demeurent limitées en Tunisie. À travers l’élaboration d’indicateurs par le modèle de programmation mathématique appliqué à des exploitations types, ce travail a montré que les coûts résultant de la surexploitation des nappes sont inégalement répartis. Les petites exploitations, disposant de moins de 3 ha, sont les plus affectées. Elles encourent des coûts de pompage de 1,25 à 1,5 fois plus élevés que les exploitations disposant d’une superficie beaucoup plus large. Le ratio bénéfice-coût de l’irrigation est également le plus faible dans cette catégorie, suggérant la non-rentabilité de l’irrigation dans un futur proche. Ce travail a révélé que l’accès économique à l’eau souterraine est désormais tributaire de la dotation de deux facteurs clés : le capital foncier et le capital financier. Les exploitations disposant de moyens fonciers et financiers vont continuer à profiter des eaux souterraines, tandis que les petites exploitations risquent d’en perdre rapidement l’accès, se trouvant ainsi exclues de leur part de cette ressource collective. Afin de préserver l’égalité d’accès pour toutes les catégories d’exploitations, et de prévenir une accentuation de la dégradation de la nappe, une politique robuste de gouvernance devrait être mise en place, avec une implication plus forte des usagers locaux et de l’administration agricole régionale.

[Display omitted] • Comparison of theoretical and experimental values of lattice and oxygen positional parameters. • Concentration dependent dielectric properties study at room temperature. • Relaxation phenomenon within the prepared samples and relaxation energy. • Three types of semicircles observed on Nyquist plots along with Bode diagrams. • Conductive/resistive behavior of grains/grain boundaries explained using Cole-Cole plots. Linear increase in crystallite size (16–24 nm) of Mn x Zn 1−x Fe 2 O 4 nanostructures and mixed behavior of lattice constant (8.429–8.462 Å) is reported. The system exhibits considerable promise for microwave applications due to its elevated dielectric constants and minimal dispersion losses from 20 Hz to 20 MHz. With x = 0.75, sample is good for energy storage devices like supercapacitors due to large specific surface area (53 m2/g) and dielectric constant. These samples exhibit maximum relaxation times ranging from 1.97 × 10−7 s to 2.43 × 10−4 s, with corresponding relaxation energy values spanning from 159.22 meV to 341 meV for x = 0 and x = 1 samples. The Cole-Cole plots reveal that grains exhibit conductive behavior at lower frequencies, while grain boundaries contribute significantly to the resistive behavior. Additionally, we have introduced Bode diagrams and equivalent electronic circuit models for the first time, offering valuable insights into the electrical behavior of the nanomaterial samples. [ABSTRACT FROM AUTHOR]

MRI-guided focused ultrasound (MRgFUS) lesioning is an innovative, safe and effective treatment which provides an innovative development in the field of minimally invasive stereotactic neurosurgery. Based on the application of focused ultrasound energy under full MR planning and thermal imaging control, unilateral lesioning of the thalamus, subthalamic nucleus, and globus pallidus is indicated for the treatment of movement disorders, including essential tremor, Parkinson's disease, and dystonia. We started to apply this technique in February 2019 for the treatment of patients with movement disorders. The authors developed a diagnostic therapeutic care pathway, which is herewith proposed and applied as an explication of standard clinical practice in use. The project was the result of the application of different methods such as Health Technology Assessment (HTA), Strengths, Weaknesses, Opportunities and Threats analysis (SWOT) and Demin -Plan, Do, Check, Act (PDCA) cycle. The aim of this project was to standardize the MRgFUS diagnostic-therapeutic pathway (DTP), describe its application and the appropriateness of different phases (patient selection, intervention phase and follow-up). Here, we described in detail our experience in the DTP application from 2019 up to now in 610 patients with movement disorders., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Rinaldo, Cilia, Leta, Gammone, Andreasi, Colucci, Braccia, Telese, Poli, Levi, Romito, Ghilemetti, De Martin, Fumagalli, Epifani, Prioni, Amami, Piacentini, Elia, Devigili, Nazzi, Ciceri, Stanziano, Grisoli, Caldiera, Catotti, DiMeco, Moreschi and Eleopra.)

Background: Magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy is increasingly used to treat drug-resistant essential tremor (ET). Data on MRgFUS thalamotomy in dystonic tremor (DT) are anecdotal., Objectives: To investigate efficacy, safety, and differences in target coordinates of MRgFUS thalamotomy in DT versus ET., Methods: Ten patients with DT and 35 with ET who consecutively underwent MRgFUS thalamotomy were followed for 12 months. Although in both groups the initial surgical planning coordinates corresponded to the ventralis intermediate (Vim), the final target could be modified intraoperatively based on clinical response., Results: Tremor significantly improved in both groups. The thalamic lesion was significantly more anterior in DT than ET. Considering both ET and DT groups, the more anterior the lesion, the lower the odds ratio for adverse events., Conclusions: MRgFUS thalamotomy is safe and effective in DT and ET. Compared to classical Vim coordinates used for ET, more anterior targeting should be considered for DT., (© 2023 The Authors. Movement Disorders Clinical Practice published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.)