Applicability of Low-Cost Binders for the Quantitative Elemental Analysis of Urinary Stones Using EDXRF Based on Fundamental Parameter Approach.

The pressed powder sample is a common method for elemental analysis using X-ray fluorescence analysis whereas suitable light hydrocarbon materials should be added to the sample as a binder. The present study demonstrates the applicability of using different commercial binders for elemental analysis of urinary stone samples. In order to confirm the obtained results, a comparison with pure chemical grade binders was presented. Different commercial and pure binders were tested for quantitative elemental analysis of urinary stones, namely, cellulose, starch, wax, and urea. Energy dispersive X-ray fluorescence (EDXRF) was used for elemental analysis. Differential thermal analysis was used to estimate the loss on ignition (LOI) in the urinary stone samples. The signal to background ratios (I/IB) of the different detected elements in the commercial and pure binders were calculated, compared, and studied at eight different photon energies starting from 2.5 up to 37 keV. Standard-less quantitative analysis method based on the fundamental parameter approach was applied for elemental analysis of selected urinary stones. The commercial and low-cost binders could be an excellent alternative binder for urinary stone analysis using energy dispersive X-ray fluorescence. The commercial binders could provide an advantage as pure chemical grade binders or even better especially at photon energy higher than 10 keV. The best commercial binder candidate was found to be the wax. The quantitative analysis results using commercial and pure chemical grade binders give good agreement results, which indicate the applicability of commercial binders for quantitative elemental analysis of urinary stones in the form of pressed powder samples.

Patient-reported health-related quality of life for men treated with low-dose-rate prostate brachytherapy as monotherapy with 125-iodine, 103-palladium, or 131-cesium: Results of a prospective phase II study.

PURPOSE: To compare quality of life (QoL) after brachytherapy with one of the three approved radioactive isotopes. METHODS AND MATERIALS: Patients with mostly favorable intermediate-risk prostate cancer were treated on this prospective phase II trial with brachytherapy as monotherapy, without hormonal therapy. QoL was recorded at baseline and each follow-up by using the Expanded Prostate Cancer Index Composite instrument. The minimal clinically important difference was defined as half the standard deviation of the baseline score for each domain. Mixed effect models were used to compare the different isotopes, and time-driven activity-based costing was used to compute costs. RESULTS: From 2006 to 2013, 300 patients were treated with iodine-125 (I-125, n = 98, prescribed dose [PD] = 145 Gy), palladium-103 (Pd-103, n = 102, PD = 125 Gy), or cesium-131 (Cs-131, n = 100, PD = 115 Gy). Median age was 64.9 years. Median follow-up time was 5.1 years for the entire cohort, and 7.1, 4.8 and 3.3 years for I-125, Pd-103, and Cs-131 groups, respectively. All three isotope groups showed an initial drop in QoL at first follow-up, which gradually improved over the first 2 years for urinary and bowel domains. QoL profiles were similar between I-125 and Pd-103, whereas Cs-131 showed a statistically significant decrease in QoL regarding bowel and sexual function at 12 months compared with Pd-103. However, these differences did not reach the minimal clinically important difference. Compared with I-125, the use of Pd-103 or Cs-131 resulted in cost increases of 18% and 34% respectively. CONCLUSIONS: The three different isotopes produced a similar QoL profile. Statistically significant differences favored Pd-103/I-125 over Cs-131 for bowel and sexual QoL, but this did not reach clinical significance.

Stylized facts of intraday precious metals.

This paper examines the stylized facts, correlation and interaction between volatility and returns at the 5-minute frequency for gold, silver, platinum and palladium from May 2000 to April 2015. We study the full sample period, as well as three subsamples to determine how high-frequency data of precious metals have developed over time. We find that over the full sample, the number of trades has increased substantially over time for each precious metal, while the bid-ask spread has narrowed over time, indicating an increase in liquidity and price efficiency. We also find strong evidence of periodicity in returns, volatility, volume and bid-ask spread. Returns and volume both experience strong intraday periodicity linked to the opening and closing of major markets around the world while the bid-ask spread is at its lowest when European markets are open. We also show a bilateral Granger causality between returns and volatility of each precious metal, which holds for the vast majority subsamples.

Sulfuration resistance of five experimental Ag-Pd-Au-Cu alloys with low Pd content of 10 or 12%.

Commercial Ag-based alloy (46Ag-20Pd-12Au-20Cu alloy) is widely used in Japan as a casting alloy. As opposed to the commercial composition, we prepared five experimental Ag-based alloys with reduced Pd content of 10 or 12%, increased Au content of 20 to 30%, and reduced Cu content of 12 to 20%. We then evaluated their sulfuration resistance by analyzing cast specimen surfaces dipped in 0.1% Na2S solution with SEM/EPMA, TF-XRD, and XPS. It became evident that all alloys were susceptible to sulfuration in the segregated Ag-rich Pd-poor phases. The degree and speed of sulfuration, however, differed among the six alloys examined. In particular, one experimental alloy (46Ag-10Pd-30Au-12Cu) possessed a sulfuration resistance equal or superior to that of commercial Ag-based alloy, while the other four experimental alloys were inferior in sulfuration resistance. Based on the results of this study, we concluded that our newly developed 46Ag-10Pd-30Au-12Cu alloy could be employed as a new sulfuration-resistant Ag-based casting alloy--which is especially useful if the price of Pd is skyrocketing again.

Palladium-103 plaque radiotherapy for choroidal melanoma: results of a 7-year study.

OBJECTIVE: To describe the first clinical experience with palladium-103 (103Pd) ophthalmic plaque radiotherapy for choroidal melanoma. DESIGN: Phase-I (nonrandomized) clinical trial. PARTICIPANTS: Eighty patients with uveal melanomas were diagnosed by clinical examination, found to be negative for metastatic disease, and offered 103Pd radioactive plaque treatment. Nine patients were concurrently treated with microwave hyperthermia. INTERVENTION: Palladium-103 ophthalmic plaque radiotherapy was employed for each patient. Eye plaques were sewn to the episclera to cover the base of the intraocular tumor, radiation was continuously delivered over 5 to 7 days, and then the plaques were removed. A mean apical dose of 81 Gy was delivered. MAIN OUTCOME MEASURES: The authors evaluated the ease of use of 103Pd seeds within standard gold eye plaques. Patient-related outcomes were control of tumor growth, change in visual acuity, the development of radiation damage (retinopathy, optic neuropathy, and cataract), and metastatic disease. RESULTS: From September 1990 to December 1997, 80 patients were treated with 103Pd and followed for an average of 38 months. Two patients were lost to follow-up. During this time, the authors found that 103Pd seeds were equivalent to iodine-125 (125I) with respect to plaque manufacture and ease of dosimetric calculations. Two patients in this series were treated for tumor recurrence after 125I plaque radiotherapy. They both failed secondary 103Pd treatment and were enucleated. When 103Pd was used as a primary treatment, it controlled the growth of 75 of 78 tumors (96%). Overall, there have been six enucleations: three failures of primary treatment, two failures of retreatment, and one for neovascular glaucoma. Visual acuity evaluations at the 36-month follow-up visit (including the enucleated patients) revealed that 38% of eyes had decreased 3 or more lines of vision, and 77% were 20/200 or better. CONCLUSION: Palladium-103 plaque radiotherapy can be used to treat uveal melanomas. Compared with 125I, computerized dosimetry suggests a more favorable dose distribution with 103Pd. Treatment of most patients resulted in tumor shrinkage and preservation of functional vision. The authors have noted no complications that might preclude the use of 103Pd ophthalmic plaque radiotherapy for choroidal melanoma.