Probing the Surface Chemistry of Nanoporous Gold via Electrochemical Characterization and Atom Probe Tomography.

Surface chemistry information is crucial in understanding catalytic and sensing mechanisms. However, resolving the outermost monolayer composition of metallic nanoporous materials is challenging due to the high tortuosity of their morphology. In this study, we first elaborate on the capabilities and limitations of atom probe tomography (APT) in resolving interfaces.

A percolation theory for designing corrosion-resistant alloys.

Iron-chromium and nickel-chromium binary alloys containing sufficient quantities of chromium serve as the prototypical corrosion-resistant metals owing to the presence of a nanometre-thick protective passive oxide film. Should this film be compromised by a scratch or abrasive wear, it reforms with little accompanying metal dissolution, a key criterion for good passive behaviour. This is a principal reason that stainless steels and other chromium-containing alloys are used in critical applications ranging from biomedical implants to nuclear reactor components.

Enabling near-atomic-scale analysis of frozen water.

Transmission electron microscopy went through a revolution enabling routine cryo-imaging of biological and (bio)chemical systems, in liquid form. Yet, these approaches typically lack advanced analytical capabilities. Here, we used atom probe tomography to analyze frozen liquids in three dimensions with subnanometer resolution.

A novel application of nanoporous gold to humidity sensing: a framework for a general volatile compound sensor.

Volatile organic compounds (VOC) are ubiquitous in industrial applications creating a pressing desire for novel transduction pathways to build a broad family of new gas sensors. Nanoporous gold (NPG) is a material with a vast range of untapped potential applications; offering a high surface area found generally in nanomaterials, while also being comparatively simple to fabricate. NPG based sensors can also leverage the unique physics of gold at the nanoscale.

Nanoscale mechanism of the stabilization of nanoporous gold by alloyed platinum.

Nanoporous gold (NPG) is usually made by electrochemical dealloying of Ag from binary AgAu alloys. The resulting nanoscale ligaments are not very stable, and tend to coarsen with time by surface self-diffusion, especially in electrolyte, which may lead to inferior electrocatalytic properties. Addition of a small amount of Pt to the precursor alloy is known to refine and stabilize the nanoporous product (NPG-Pt).

Pitting of steam-generator tubing alloys in solutions containing thiosulfate and sulfate or chloride.

The pitting of nuclear steam generator tubing alloys 600, 690 and 800 was studied at 60 °C using dilute thiosulfate solutions containing excess sulfate or (for Alloy 600) chloride. A potentiostatic scratch method was used. In sulfate solutions, all alloys pitted at low potentials, reflecting their lack of protective Mo.

Using novel methodologies to examine the impact of artificial light at night on the cortisol stress response in dispersing Atlantic salmon (Salmo salar L.) fry.

Artificial light at night (ALAN) is gaining recognition as having an important anthropogenic impact on the environment, yet the behavioural and physiological impacts of this stressor are largely unknown. This dearth of information is particularly true for freshwater ecosystems, which are already heavily impacted by anthropogenic pressures. Atlantic salmon (Salmo salar L.

Analytical electron microscopy of a crack tip extracted from a stressed Alloy 800 sample exposed to an acid sulfate environment.

Alloy 800 (Fe-21Cr-33Ni) has been found susceptible to cracking in acid sulfate environments, but the mechanism is not well understood. Alloy 800 C-ring samples were exposed to an acid sulfate environment at 315°C and cracks were found with depths in excess of 300μm after 60h. Preparation of a TEM sample containing crack tips is challenging, but the ability to perform high-resolution microscopy at the crack tip would lend insight to the mechanism of acid sulfate stress corrosion cracking (AcSCC).

A tribute to the life and accomplishments of Birdwell Finlayson.

Purpose: Birdwell Finlayson was a talented researcher and clinician whose pioneering work in the field of urolithiasis led him to worldwide prominence in urology. We researched his life and accomplishments to provide a historical account of his career.

Materials And Methods: The archives of the Department of Urology and the University of Florida Health Science Center Library were searched for publications, photographs and other records relating to Doctor Finlayson.

Study of the resistance of SAMs on aluminium to acidic and basic solutions using dynamic contact angle measurement.

We report the development of a method to determine the aqueous stability of self-assembled monolayers (SAMs) using the Wilhelmy plate dynamic contact angle (DCA) experiment. The DCA is measured in solutions over a range of pH values for alkyl carboxylic and alkyl phosphonic acid SAMs formed on magnetron-sputtered aluminum. The change in DCA on repeated immersion is used as a measure of the degradation of the SAMs by hydrolytic attack.

Spurious hypocalcemia after gadodiamide-enhanced magnetic resonance imaging: a case report and review of the literature.

Gadolinium-enhanced magnetic resonance imaging is a diagnostic modality widely used in urologic practice. We report on a 54-year-old woman in whom a critically low serum calcium level was measured with standard colorimetric assay after gadodiamide-enhanced magnetic resonance imaging. The same phenomenon was noted in 2 other patients seen in our practice.

Patient-reported outcomes for open versus laparoscopic living donor nephrectomy.

Background: Rates of living kidney donation have increased dramatically in recent years, in large part because of improved surgical techniques such as laparoscopic nephrectomy.

Objective: To compare patient-reported outcomes of laparoscopic nephrectomy versus open donor nephrectomy in 84 adult live kidney donors.

Outcome Measures: Outcomes included perceptions of pain and surgical scarring, number of surgical/medical complications, hospital length of stay, physical health problems related to donation, return to work, financial impact, health-related quality of life, and satisfaction with the donation experience.

The expectancies of living kidney donors: do they differ as a function of relational status and gender?

Background: While two-thirds of the living kidney donors continue to be genetically related to the recipient, there has been a 300% increase in unrelated living donors over the last 10 years. Also, women continue to represent more than half of all the living kidney donors. This study examined whether donor expectancies varied as a function of relational status or gender.

Vibrational lifetimes and isotope effects of interstitial oxygen in silicon and germanium.

Decay dynamics of local vibrational modes provides unique information about energy relaxation processes to solid-state phonon bath. In this Letter the lifetimes of the asymmetric stretch mode of interstitial 16O and 17O isotopes in Si are measured at 10 K directly by time-resolved, transient bleaching spectroscopy to be 11.5 and 4.

Ureteroscopic management of ureteral and ureteroenteral strictures.

The ureteroscopic approach to ureteral strictures has diminished morbidity because of smaller-caliber equipment, improved optics, Ho:YAG laser, and a better understanding of the risk factors for ureteral strictures. Direct visualization by means of retrograde ureteroscopy provides a safe and effective approach to treat ureteral strictures without the need for an open incision or percutaneous nephrostomy access. All patients with a ureteral stricture require an extensive evaluation and planning before treatment.

Lower pole I: a prospective randomized trial of extracorporeal shock wave lithotripsy and percutaneous nephrostolithotomy for lower pole nephrolithiasis-initial results.

Purpose: The efficacy of shock wave lithotripsy and percutaneous stone removal for the treatment of symptomatic lower pole renal calculi was determined.

Materials And Methods: A prospective randomized, multicenter clinical trial was performed comparing shock wave lithotripsy and percutaneous stone removal for symptomatic lower pole only renal calculi 30 mm. or less.

Three-dimensional measurement of essential tremor.

A mechanical linkage device was used to measure the three-dimensional position of the fingertip during a postural task. Thirty patients with essential tremor were tested simultaneously with the device, uniaxial accelerometry, and clinical tremor measures. Eighteen patients were tested again 16+/-4 days later.

Laparoscopic complications in markedly obese urologic patients (a multi-institutional review).

Objectives: Significant obesity is considered to be a relative contraindication to laparoscopic surgery. This study reviews the complications encountered in massively obese patients undergoing urologic laparoscopic surgery.

Methods: Body mass index (BMI) was used as an objective index to indicate massive obesity.

Treatment of pediatric urolithiasis between 1984 and 1994.

Purpose: We report our experience with the management of pediatric urolithiasis during a 10-year period. Our aim was to assess the impact of new technology in the treatment of pediatric urolithiasis.

Materials And Methods: We retrospectively reviewed the records of all patients up to age 18 years in whom urolithiasis was treated from 1984 to 1994.