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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]

Copyright of Gazi Journal of Engineering Sciences (GJES) / Gazi Mühendislik Bilimleri Dergisi is the property of Gazi Journal of Engineering Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

Copyright of Molecular Imaging & Radionuclide Therapy is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Various grate inlets are commonly used for different purposes. Since the grate inlets' water-catching capacity depends on many factors, defining the best option is crucial for a sustainable drainage system. In this study, four cases with the same length, width, and void area but different geometries have been numerically studied to establish to which extent the design difference in the grate inlet affects the water-catching capacity. It has been determined how much of the approaching flow is caught by the grate inlets placed on the road with constant transverse and longitudinal slopes. The most efficient case is examined in more detail to determine the effect of the void area location on the water-catching capacity. The numerical results are discussed by comparing them with the analytical results. It has been confirmed that the location and shape of the void areas have an essential effect on the efficiency of grate inlets. Even though the void area is equal, it is concluded that the continuous void areas are more effective than the discontinuous areas. According to the results, choosing the most suitable grate among the alternative inlet designs is possible, or developing a more effective new design using numerical results provides the opportunity to compare the designs. [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]

In this study, a numerical investigation has been performed to examine the effect of the height of panel radiators above the floor. A radiator of the Panel-Convector-Convector-Panel (PCCPtype 22) was located in front of the wall where a window was placed in the 3D computational domain. Analyses were made using distances of 0.0, 1.0, 2.5, 5.0, 7.5 and 10.0 cm between radiator and floor. The results suggest that the thermal efficiency of the radiator is lowest at a level of 0 cm, which is the case when the radiator is placed on the floor. When the radiator level is insufficient, the air intake is not enough to obtain maximum heat transfer between the panels. If the radiator level is more than the optimum level, although the temperature decreases in the occupied zone, it is accumulated in the ceiling part of the room. This study also suggests that the air velocity in the collectors between the panels is a dominant parameter that affects the efficiency of the radiator. [ABSTRACT FROM AUTHOR]

Copyright of Molecular Imaging & Radionuclide Therapy is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Molecular Imaging & Radionuclide Therapy is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Molecular Imaging & Radionuclide Therapy is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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 behaviour of an inclined water jet, which is impinged onto hydrophobic and superhydrophobic surfaces, has been investigated experimentally. Water jet was impinged with different inclination angles (15°-45°) onto five different hydrophobic surfaces made of rough polymer, which were held vertically. The water contact angles on these surfaces were measured as 102°, 112°, 123°, 145° and 167° showing that the last surface was superhydrophobic. Two different nozzles with 1.75 and 4 mm in diameters were used to create the water jet. Water jet velocity was within the range of 0.5-5 m/s, thus the Weber number varied from 5 to 650 and Reynolds number from 500 to 8,000 during the experiments. Hydrophobic surfaces reflected the liquid jet depending on the surface contact angle, jet inclination angle and the Weber number. The variation of the reflection angle with the Weber number showed a maximum value for a constant jet angle. The maximum value of the reflection angle was nearly equal to half of the jet angle. It was determined that the viscous drag decreases as the contact angle of the hydrophobic surface increases. The drag force on the wall is reduced dramatically with superhydrophobic surfaces. The amount of reduction of the average shear stress on the wall was about 40%, when the contact angle of the surface was increased from 145° to 167°. The area of the spreading water layer decreased as the contact angle of the surface increased and as the jet inclination angle, Weber number and Reynolds number decreased. [ABSTRACT FROM AUTHOR]