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This study investigates the impact of baffles on fuel sloshing behavior within truck fuel tanks using numerical simulations. The volume of the fluid multiphase model is employed to analyze the flow dynamics of 25% diesel fuel in a 250 L tank, modeled in a 3D domain. Two configurations were compared: a tank with baffles and one without. The primary focus is to analyze fuel distribution within the intake port region during vehicle acceleration and deceleration maneuvers. The simulated scenario mimics a realistic driving situation. The vehicle accelerates from 0 km/h to 60 km/h over 10 s, followed by a 3-s braking period to reach a complete stop (0 km/h) at the 13-s mark. The simulation then observes the fuel behavior within the tank for an additional 7 s while the vehicle remains stationary. Results reveal significant differences in fuel behavior between baffled and unbaffled tanks. In the absence of baffles, the sloshing motion is substantial, leading to a complete depletion of fuel in the intake port region for a duration of 3 s during both the acceleration and deceleration phases (between 10 and 13 s). Compared to a standard tank, the presence of baffles significantly reduced the sloshing amplitude by approximately 70%. Furthermore, baffles led to a 50% decrease in pressure variations on the tank walls. Temporary fuel starvation can negatively impact engine performance and combustion efficiency. Conversely, the presence of baffles within the tank effectively mitigates sloshing and ensures continuous fuel presence at the intake port the entire simulation. This suggests that baffles play a crucial role in maintaining a stable and consistent fuel supply to the engine, even during dynamic vehicle maneuvers. [ABSTRACT FROM AUTHOR]

The effect of current on resistance spot welding joints on metallurgic and mechanical properties is investigated experimentally using galvanized unequal-thickness DP600 steel sheets. The specimens were chosen to be 1.5 and 1.8 mm thicknesses. The parameters of the welding process were preferred as an electrode force at 5 kN, welding currents at 7, 9, 11, 13 and 15 kA and welding times at 180, 240, 300, 360 and 420 ms. The welded joint specimens were subject to tensile-shear strength testing to determine the ultimate tensile strength. Optimal specimens were inspected using optical microscopes and scanning electron microscopy. The effect of spot welding variables on the ultimate tensile strength was determined and the lobe diagram, which shows optimal current-time values, was obtained. The optimal welding parameters were carried out on new sheet metals successfully. The experimental results show that the welding current plays an important role in the especially crash energy absorption and load-carrying capability. [ABSTRACT FROM AUTHOR]

Purpose: In our study, our aim was to investigate the role of [68 Ga]Ga-PSMA-11 PET /CT imaging in the diagnosis of clinically significant prostate cancer (csPCa) (ISUP GG 2 and higher) in patients initially diagnosed with ISUP GG 1 and 2 after prostate biopsy. Materials and methods: We retrospectively reviewed 147 patient records in whom [68 Ga]Ga-PSMA-11 PET/CT imaging was performed preoperatively. All patients were initially diagnosed with ISUP GG 1 and 2 PCa by biopsy. Final pathology reports were obtained after radical prostatectomy. The [68 Ga]Ga-PSMA-11 PET/CT images were evaluated to determine the PRIMARY score. Patients' mpMRI-PIRADS scores were also recorded when available and analyzed in correlation with the pathology results. Results: For the 114 patients scored using PRIMARY, 19 out of 37 patients with scores of 1 and 2 (51%) were diagnosed with csPCa. Of the 77 patients with PRIMARY scores between 3 and 5, 64 (83%) had csPCa. Notably, every patient with a PRIMARY score of 5 had csPCa. PRIMARY scoring had a sensitivity of 77% and specificity of 58%, with a positive predictive value of 83%. A moderate correlation was observed between PRIMARY scores and ISUP GG (Rho = 0.54, p < 0.001). In contrast, the PIRADS score displayed a sensitivity and specificity of 86% and 25% respectively, with a positive predictive value of 68%. No substantial correlation was found between PIRADS and ISUP GG. Statistical analysis revealed a significant correlation between PRIMARY and ISUP GG (p < 0.001), but not between PIRADS and ISUP GG (p = 0.281). Comparatively, PRIMARY scoring was significantly more reliable than PIRADS scoring in identifying csPCa. Conclusion: [68 Ga]Ga-PSMA-11 PET/CT imaging is promising for distinguishing high-risk prostate cancer patients from those apt for active surveillance, potentially aiding in the identification of csPCa. [ABSTRACT FROM AUTHOR]

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We present the case of a 58-year-old man with advanced medullary thyroid carcinoma who had a treatment history with different types of modalities. In the follow-up, the patient had rising calcitonin and CEA levels. Metastatic lymph nodes, liver, and bone metastases with varying degrees of uptake were detected on 18F-fluorodeoxyglucose (FDG) and 68Ga-DOTATATE positron emission tomography/computed tomography (PET/CT). 68Ga prostate-specific membrane antigen (PSMA) PET/CT was performed to explore whether the patient might have a chance for PSMAtargeted radionuclide therapy, and increased PSMA expression was noted in most of the metastatic lesions, even some of which have higher PSMA uptake than 18F-FDG and 68Ga-DOTATATE. [ABSTRACT FROM AUTHOR]

Objective: Neuroendocrine tumors are rare neoplasms that often arise from neuroendocrine cells in gastro-entero-pancreatic and bronchopulmonary tissues. Bone metastases are observed less frequently than liver metastases. In current oncological practice, Ga-68 DOTA-labeled peptide positron emission tomography/computed tomography is performed in neuroendocrine tumor patients. Thanks to positron emission tomography/magnetic resonance imaging devices developed in recent years, it has become possible to obtain positron emission tomography images and magnetic resonance imaging sequences. This study aimed to compare the diagnostic efficiency between Ga-68 DOTA TATE positron emission tomography and magnetic resonance imaging components in detecting bone metastases in patients with neuroendocrine tumor undergoing Ga-68 DOTA TATE positron emission tomography/magnetic resonance imaging. Methods: This study included 63 patients with neuroendocrine tumor who underwent Ga-68 DOTA TATE positron emission tomography/magnetic resonance imaging screening. First, positron emission tomography images and magnetic resonance imaging sequences were evaluated separately to detect bone metastases. Afterward, both the components were assessed together, and their contribution was investigated according to positron emission tomography images alone. Results: Patient-based sensitivity, specificity, positive predictive value, negative predictive value, and accuracy analysis for bone metastasis were 0.96, 0.87, 0.82, 0.97, and 0.90 for positron emission tomography and 0.71, 0.87, 0.77, 0.82, and 0.80 for magnetic resonance imaging, respectively. Diffusion-weighted imaging and short-tau inversion recovery sequences do not seem to provide any additional benefit to the clinical approach. Conclusion: Ga-68 DOTA TATE positron emission tomography/magnetic resonance imaging evaluated bone lesions in neuroendocrine tumor patients with high sensitivity but low specificity. Our study shows that diffusion-weighted imaging and short-tau inversion recovery sequences do not contribute to the clinical approach and lead to ambiguous results. It is thought that removing these sequences from the protocol will increase patient compliance, and prospective studies involving large patient groups are needed. [ABSTRACT FROM AUTHOR]

Ovarian cancer is one of the deadliest tumors among women. It mostly metastasizes to the liver, pleura, lungs, and bones. We present a sixty-six-year-old patient with skin lesions. The patient who underwent biopsy due to skin lesions was diagnosed with ovarian cancer. 18F-fluorodeoxyglucose (FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) performed for metastasis search shows widespread skin involvement, especially in the lower abdomen and legs. Skin involvement it ovarian cancer can be rarely seen, and in this article we would like to share 18F-FDG PET/MRI of skin involvement in ovarian cancer. [ABSTRACT FROM AUTHOR]

Behcet's syndrome (BS) is a variable vessel vasculitis with multi-organ involvement. Recurrent episodes of oral and genital ulcers, papulopustular and erythema nodosum-like skin lesions, and arthritis are relatively more frequent, whereas uveitis, venous and arterial lesions, nervous system, and gastrointestinal involvement are less common, but are severe manifestations. The frequency of gastrointestinal involvement shows important variation between countries as more common in the Far East and the United States, and much less common in Turkey and the Middle East. The main clinical signs of gastrointestinal Behcet's disease include abdominal pain, diarrhea, blood in the stool, fever, and weight loss. Ulcers seen in the terminal ileum, cecum, and ascending colon are common endoscopic findings. Herein, we presented the positron emission tomography/magnetic resonance imaging findings of gastrointestinal involvement in BS. [ABSTRACT FROM AUTHOR]

In this study, the spreading profiles of the impinging liquid jets on the superhydrophobic/hydrophobic surfaces have been examined experimentally and predicted using experimental data. The liquid jet is sent on the flat and smooth hydrophobic surfaces, which have 93, 104 and 117° contact angles, using the glass tube nozzle with the 1.75 mm inner diameter. The inclination angles between the jet and surface are altered in the range of 15-45°. The predicted profiles compared with the experimental data. The spreading behaviour of the impinging liquid jet on the hydrophobic surface is clarified using the predicted equation. The inclination angle is a dominant parameter for the profile of the spreading liquid. The predicted equation is in a good agreement with the experiments. The front length of the spreading liquid takes the maximum value at a critical inclination angle. [ABSTRACT FROM AUTHOR]

There are a lot of mosques which have panel radiators for heating purposes since this method is very common in Turkey. In this study, the effect of the efficiency of panel radiators, which are used for heating mosque, was investigated numerically using the STAR CCM+ software. The 3D mosque model which has a 20x20 m floor area and 29.5 m dome height is used for modelling. The temperatures of the radiators are kept at 60 °C. The temperature distribution is investigated at the end of 1 and 1.5 hours. The heating of the volume of space in which worship takes place, which is less than ~2 m in height, can be achieved after the other volume is heated. Given that the heating takes a long time, there are large differences in temperature between these volumes. Therefore, this study has proved numerically that the use of radiators for heating of mosque in heating of mosques of a large internal volume is absolutely unsuitable. [ABSTRACT FROM AUTHOR]

In this study, the differences between the hydrophobic and superhydrophobic surfaces from the hydrophilic surfaces and dynamics of a liquid droplets, gas bubbles and liquid jets have been examined. For a droplet, there remains a large contact angle on the superhydrophobic surfaces, while the gas bubble spreads on the surface with a low contact angle. There are two different conditions for superhydrophobic surfaces (i.e., Cassie and Wenzel) and the contact angles are high for those two surfaces. However, contact angle hysteresis is low and high for the Cassie and Wenzel states, respectively. The droplet remains on the superhydrophobic surface touching a small area with the surface, and it can be removed from the surface by a very low external forces. When the superhydrophobic surfaces are submerged in a liquid, it is covered by a thin air layer. In this case, the air bubble, which is sent from underneath of the surface, bursts and disappears on the surface. The superhydrophobic surfaces have potential applications for icing, film/dropwise condensation and boiling. [ABSTRACT FROM AUTHOR]

Abstract: Amyloidosis is a protein misfolding disorder characterized by the extracellular deposition of insoluble amyloid fibrils, derived from abnormally folded proteins. These fibrils disrupt tissue structure and function, leading to organ dysfunction. The condition encompasses various subtypes, each associated with distinct precursor proteins and clinical manifestations. 99mTc-PYP scintigraphy is used widely and holds significant importance for diagnosis. 68Ga-FAPI is also a promising radiotracer for various diseases. To our knowledge, this is the first case of a patient with hereditary transthyretin amyloidosis with cardiac involvement, which FAPI PET showed diffuse increased myocardial uptake., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

We present the case of a 58-year-old man with advanced medullary thyroid carcinoma who had a treatment history with different types of modalities. In the follow-up, the patient had rising calcitonin and CEA levels. Metastatic lymph nodes, liver, and bone metastases with varying degrees of uptake were detected on 18 F-fluorodeoxyglucose (FDG) and 68 Ga-DOTATATE positron emission tomography/computed tomography (PET/CT). 68 Ga prostate-specific membrane antigen (PSMA) PET/CT was performed to explore whether the patient might have a chance for PSMA-targeted radionuclide therapy, and increased PSMA expression was noted in most of the metastatic lesions, even some of which have higher PSMA uptake than 18 F-FDG and 68 Ga-DOTATATE., Competing Interests: Conflict of Interest: No conflicts of interest were declared by the authors., (Copyright© 2024 The Author. Published by Galenos Publishing House on behalf of the Turkish Society of Nuclear Medicine.)

Ovarian cancer is one of the deadliest tumors among women. It mostly metastasizes to the liver, pleura, lungs, and bones. We present a sixty-six-year-old patient with skin lesions. The patient who underwent biopsy due to skin lesions was diagnosed with ovarian cancer. 18 F-fluorodeoxyglucose (FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) performed for metastasis search shows widespread skin involvement, especially in the lower abdomen and legs. Skin involvement it ovarian cancer can be rarely seen, and in this article we would like to share 18 F-FDG PET/MRI of skin involvement in ovarian cancer., Competing Interests: Conflict of Interest: No conflict of interest was declared by the authors., (©Copyright 2023 by the Turkish Society of Nuclear Medicine / Molecular Imaging and Radionuclide Therapy published by Galenos Publishing House.)

Behcet's syndrome (BS) is a variable vessel vasculitis with multi-organ involvement. Recurrent episodes of oral and genital ulcers, papulopustular and erythema nodosum-like skin lesions, and arthritis are relatively more frequent, whereas uveitis, venous and arterial lesions, nervous system, and gastrointestinal involvement are less common, but are severe manifestations. The frequency of gastrointestinal involvement shows important variation between countries as more common in the Far East and the United States, and much less common in Turkey and the Middle East. The main clinical signs of gastrointestinal Behcet's disease include abdominal pain, diarrhea, blood in the stool, fever, and weight loss. Ulcers seen in the terminal ileum, cecum, and ascending colon are common endoscopic findings. Herein, we presented the positron emission tomography/magnetic resonance imaging findings of gastrointestinal involvement in BS.