One-Step Synthesis of Tunable-Size Gold Nanoplates on Graphene Multilayers.

Au nanoplates (quasi-two-dimensional single crystals) are most commonly synthesized using a mixture of Au precursors via approaches involving multiple processing steps and the use of seed crystals. Here, we report the synthesis of truncated-hexagonal {111}-oriented micrometer-scale Au nanoplates on graphene multilayers using only potassium tetrabromoaurate (KAuBr4) as the precursor. We demonstrate that the nanoplate sizes can be controllably varied from tens of nanometers up to a few micrometers by introducing desired concentrations of chloroauric acid (HAuCl4) to KAuBr4 and their thicknesses from ∼13 to ∼46 nm with the synthesis time. Through a series of experiments carried out as a function of synthesis time and precursor composition [mixtures of HAuCl4 and KAuBr4, KBr, or ionic liquid 1-butyl-3-methylimidazolium bromide ([Bmim]Br)], we identify the optimal HAuCl4 and KAuBr4 concentrations and synthesis times that yield the largest and the thinnest size nanoplates. We show that the nanoplates are kinetically limited morphologies resulting from preferential growth of {111} facets facilitated by bromide ions in KAuBr4 solutions; we suggest that the presence of chloride ions enhances the rate of Au deposition and the relative concentration of chloride and bromide ions determines the shape anisotropy of resulting crystals. Our results provide new insights into the kinetics of nanoplate formation and show that a single precursor containing both Au and Br is sufficient to crystallize nanoplates on graphitic layers, which serve as reducing agent while enabling the nucleation and growth of Au nanoplates. We suggest that a similar approach may be used for the synthesis of nanoplates of other metals on weakly interacting van der Waals layers for, potentially, a variety of new applications.

Association of vesicoureteral reflux and gastroesophageal reflux disease in children: A population-based study.

INTRODUCTION: Practitioners have anecdotally hinted at a possible association between gastroesophageal reflux disease (GERD) and vesicoureteral reflux (VUR). We sought to identify an association in diagnosis between GERD and VUR using a population-based dataset in a well-defined geographic area covered by a single-payer healthcare system. METHODS: A retrospective review of individuals aged 0-16 years registered in the Nova Scotia Medical Service Insurance database from January 1997 to December 2012 was completed. Presence of GERD and VUR were ascertained based on billing codes. The baseline prevalence of GERD and VUR was calculated for this population for the same time period. Proportions of VUR patients with and without GERD were compared. The risk of being diagnosed with VUR in patients with GERD controlling for sex was calculated. RESULTS: Of 404 300 patients identified, 6.6% had a diagnosis of GERD (n=27 092), 0.33% had a diagnosis of VUR (n=1348), and 0.08% were diagnosed with both (n=327). Among patients with VUR, the prevalence of GERD was 24.3% compared to 6.6% in patients without VUR (p<0.0001). Among patients with GERD, the prevalence of VUR was 1.2% compared to 0.27% in patients without (p<0.0001). The risk of being diagnosed with VUR was higher in the presence of GERD (odds ratio [OR] 4.49; 95% confidence interval [CI] 3.96-5.09; p<0.0001), irrespective of sex. CONCLUSIONS: The odds of being diagnosed with VUR is more than 4.5 times higher in an individual with GERD. The clinical significance of this association remains to be explored.

Shockwave Lithotripsy Practice Pattern Variations Among and Between American and Canadian Urologists: In Support of Guidelines.

PURPOSE: Shockwave lithotripsy (SWL) is a widely utilized form of treatment for urolithiasis. There are new evidence-based recommendations regarding pre-SWL patient work-up and the performance of SWL. The purpose of this study is to determine practice patterns for SWL and to determine if regional variation exists between Canada and the United States. MATERIALS AND METHODS: A 19-question survey was prepared. Canadian urologists were surveyed through e-mail correspondence. In the United States, members of the Endourologic Society and members of two large stone management groups were surveyed. Canadian and American results were compared using the chi-square and Fisher's exact tests. RESULTS: Ninety-four Canadian urologists and 187 U.S. urologists completed the survey. Practice patterns differed between countries. Intravenous sedation was more commonly used in Canada (Canada 94.7% vs United States 17.9%, p < 0.001); routine antibiotics were more commonly given in United States (Canada 2.1% vs United States 78.1%, p < 0.001); a shock rate of 2 Hz was more common in Canada (Canada 76.6% vs United States 16.2%, p < 0.00001); rate of discontinuing ASA for renal and ureteral stone treatment was higher in the United States (renal Canada 88.3% vs United States 95.7%, p < 0.02; ureteral Canada 62.4% vs 90.3%, p < 0.0001); and ureteral stents were more commonly used if treating a large stone or patients with solitary kidneys in the United States (large stones Canada 58.2% vs United States 88.8%, p = 0.0001; solitary kidney Canada 50.6% vs 66.3%, p = 0.02). CONCLUSIONS: This study highlights the absence of standardization of SWL. Significant regional differences exist in practice patterns and performance of SWL between Canadian and American urologists.

Inguinoscrotal hernias involving urologic organs: A case series.

We report 2 cases of inguinoscrotal hernias involving urologic organs. The first case involved an elderly gentleman with a history of micturition by squeezing his scrotum. He was diagnosed as having a right-sided indirect inguinal hernia involving the right ureter and bladder. Treatment was surgical. The second case involved an achondroplastic male who presented with acute kidney injury. He had bilateral hydronephrosis and ureteric obstruction secondary to an ureteroinguinal herniation bilaterally. The presentation, diagnosis, and treatment of inguinoscrotal hernias involving the bladder and ureters are discussed.