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OBJECTIVE: Cisplatin is a widely used and potent cytotoxic chemotherapy agent, but its nephrotoxicity is a significant limiting side effect. Various premedication approaches have been implemented to preserve renal function, including magnesium (Mg) preloading. However, the optimal Mg dosage is still unknown. Our study aimed to assess the protective effects of different Mg doses as premedication in cisplatin-based chemoradiotherapy for patients with local/locally advanced cervical and head-neck cancers. PATIENTS AND METHODS: This retrospective, multicenter study involved premedication with saline infusion containing potassium chloride and magnesium sulfate (MgSO4) for all patients before cisplatin treatment. Patients were divided into two groups: 12 mEq MgSO4 (lowdose Mg preload group, low-Mg) and 24 mEq MgSO4 (high-dose Mg preload group, high-Mg). Renal function was evaluated using serum creatinine (sCr, mg/dl) and estimated glomerular filtration rate (eGFR, ml/min). Acute kidney injury (AKI) was defined per the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Renal outcomes and efficacy were compared between the groups. RESULTS: In the low-Mg group (n = 159), sCr levels were significantly higher compared to baseline, various weeks during treatment, and at the 1st, 3rd, 6th, and 12th months post-treatment (p < 0.001). In the high-Mg group (n = 128), no significant changes were observed during treatment and at 1st, 3rd, and 12th months post-treatment (p > 0.05). A significant reduction in mean sCr level from baseline to 6 months was noted in the high-Mg group (p < 0.001). eGFR values are generally correlated with sCr levels. AKI occurred in 21 (13.2%) and 22 (17.7%) patients in the low-Mg and high-Mg groups, respectively (p = 0.292). There was no difference in progression-free or overall survival between the groups. CONCLUSIONS: We clearly demonstrated that saline hydration with 24 mEql MgSO4 supplementation before cisplatin treatment has a better renal protective effect than 12 mEql Mg-SO4 without reducing efficacy, especially in patients with local/local advanced cervical and head-neck cancer receiving cisplatin with concurrent radiotherapy. [ABSTRACT FROM AUTHOR]

Film-cooling effectiveness is measured on a rotating turbine blade platform for coolant injection through discrete holes using pressure sensitive paint technique. Most of the existing literatures provide information only for stationary endwalls. The effects of rotation on the platform film-cooling effectiveness are not well documented. Hence, the existing three-stage turbine research facility at the Turbomachinery and Flow Performance Laboratory, Texas A&M University was redesigned and installed to enable coolant gas injection on the first stage rotor platform. Two distinct coolant supply loops were incorporated into the rotor to facilitate separate feeds for upstream cooling using stator-rotor gap purge flow and downstream discrete-hole film cooling. As a continuation of the previously published work involving stator-rotor gap purge cooling, this study investigates film-cooling effectiveness on the first stage rotor platform due to coolant gas injection through nine discrete holes located downstream within the passage region. Filmcooling effectiveness is measured for turbine rotor frequencies of 2400 rpm, 2550 rpm, and 3000 rpm corresponding to rotation numbers of [R.sub.o] = 0.18, 0.19, and 0.23, respectively. For each of the turbine rotational frequencies, film-cooling effectiveness is determined for average film-hole blowing ratios Of [M.sub.holes] = 0.5, 0.75, 1.0, 1.25, 1.5, and 2.0. To provide a complete picture of hub cooling under rotating conditions, simultaneous injection of coolant gas through upstream stator-rotor purge gap and downstream discrete film-hole is also studied. The combined tests are conducted for gap purge flow corresponding to coolant to mainstream mass flow ratio of MFR = 1% with three downstream film-hole blowing ratios of [M.sub.holes] = 0.75, 1.0, and 1.25 for each of the three turbine speeds. The results for combined upstream stator-rotor gap purge flow and downstream discrete holes provide information about the optimum purge flow coolant mass, average coolant hole blowing ratios for each rotational speed, and coolant injection location along the passage to obtain efficient platform film cooling. [DOI: 10.1115/1.3142860]

This paper experimentally investigates the individual and combined effects of periodic unsteady wake flows and freestream turbulence intensity (FSTI) on flow separation along the suction surface of a low-pressure turbine blade. The experiments were carried out at a Reynolds number of 110,000 based on the suction surface length and the cascade exit velocity. The experimental matrix includes freestream turbulence intensities of 1.9%, 3.0%, 8.0%, and 13.0%, and three different unsteady wake frequencies with the steady inlet flow as the reference configuration. Detailed boundary layer measurements are performed along the suction surface of a highly loaded turbine blade with a separation zone. Particular attention is paid to the aerodynamic behavior of the separation zone at different FSTIs at steady and periodic unsteady flow conditions. The objective of the research is (i) to quantify the effect of FSTIs on the dynamics of the separation bubble at steady inlet flow conditions and (ii) to investigate the combined effects of Tuin and the unsteady wake flow on the behavior of the separation bubble. [DOI: 10.1115/1.2734188]

The paper experimentally studies the effects of periodic unsteady wake flow and Reynolds number on boundary, layer development, separation, reattachment, and the intermittency behavior along the suction surface of a low pressure turbine blade. Extensive unsteady boundary layer experiments were carried out at Reynolds numbers of 110,000 and 150,000 based on suction surface length and exit velocity. One steady and two different unsteady inlet flow conditions with the corresponding passing frequencies, wake velocities, and turbulence intensities were investigated. The analysis of the experimental data reveals details of boundary layer separation dynamics which is essential for understanding the physics of the separation phenomenon under periodic unsteady wake flow and different Reynolds numbers. To provide a complete picture of the transition process and separation dynamics, extensive intermittency analysis was conducted. Ensemble-averaged maximum and minimum intermittency functions were determined, leading to the relative intermittency function. In addition, the detailed intermittency analysis was aimed at answering the question as to whether the relative intermittency of a separated flow fulfills the universality criterion. [DOI: 10.1115/1.2219762]

The paper experimentally studies the effects of periodic unsteady wake flow on boundary layer development, separation and reattachment along the suction surface of a low pressure turbine blade. The experimental investigations were performed on a large scale, subsonic unsteady turbine cascade research facility at the Turbomachinery Performance and Flow Research Laboratory (TPFL), Texas A&M University. The experiments were carried out at a Reynolds number of 110,000 (based on suction surface length and exit velocity) with a free-stream turbulence intensity of 1.9%. One steady and two different unsteady inlet flow conditions with the corresponding passing frequencies, wake velocities, and turbulence intensities were investigated. The reduced frequencies cover the entire operating range of LP turbines. In addition to the unsteady boundary layer measurements, blade surface measurements were performed at the same Reynolds number. The surface pressure measurements were also carried out at one steady and two periodic unsteady inlet flow conditions. The results presented in ensemble-averaged, and the contour plot forms help to understand the physics of the separation phenomenon under periodic unsteady wake flow. It was found that the suction surface displayed a strong separation bubble for these three different reduced frequencies. For each condition, the locations and the heights defining the separation bubble were determined by carefully analyzing and examining the pressure and the mean velocity profile data. The location of boundary layer separation was independent of the reduced frequency level. However, the extent of the separation was strongly dependent on the reduced frequency level. Once the unsteady wake started to penetrate into the separation bubble, the turbulent spot produced in the wake paths caused a reduction of the separation bubble height.