Publications by authors named "Daniel Lehman"

As part of the Integrated Atmospheric Deposition Network, precipitation ( = 207) and air ( = 60) from five sites and water samples ( = 87) from all five Great Lakes were collected in 2021-2023 and analyzed for 41 per- and polyfluoroalkyl substances (PFAS). These measurements were combined with other available data to estimate the mass budget for four representative compounds, PFBA, PFBS, PFOS, and PFOA for the basin. The median ΣPFAS concentrations in precipitation across the five sites ranged between 2.

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Although diet is an important route of exposure for brominated flame retardants (BFRs), little is known of their presence in US food. Therefore, we purchased meat, fish, and dairy product samples ( = 72) in Bloomington, IN, from 3 stores representing national retail chains at different price levels. Composite samples ( = 42) were analyzed for polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), novel BFRs (NBFRs), and dechlorane plus (DP).

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Thirty-five polybrominated diphenyl ethers (PBDEs) and eight other alternative flame retardants were measured in air samples (vapor plus particles) collected at six sites near the North American Great Lakes between 2005 and 2019 as part of the Integrated Atmospheric Deposition Network (IADN). These data were analyzed using a multiple linear regression model to determine spatial and temporal trends. Overall, the levels of flame retardants remain significantly higher in urban sites compared to rural and remote sites except for pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), and total Dechlorane Plus (ΣDP).

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We define here "temporal environmental hysteresis" as the time lag between when a pollutant's input to the environment stops and when its concentration in the environment drops to some desired fraction of its maximum concentration. The goal of this paper is to investigate temporal environmental hysteresis for polybrominated diphenyl ethers (PBDEs), which were widely used as flame retardants in consumer goods. These compounds were taken off the North American market in two steps: At the end of 2004, the so-called Penta-BDE and Octa-BDE products were withdrawn, and at the end of 2013, the Deca-BDE product was also discontinued.

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Data on atmospheric levels of toxic pollutants in samples collected near the Great Lakes are now readily available online to scientists, researchers, and the public on a website called IADN Data Viz (https://iadnviz.iu.edu/).

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Dechlorane Plus (DP) is a chlorinated flame retardant manufactured only in Niagara Falls, New York and in Huai'an, China. To determine if the environmental levels of this compound were changing significantly, we measured the long-term temporal trends of its concentrations near the Great Lakes between 2005 and 2015 using air (vapor + particle phase) samples (N = 1047) and precipitation samples (N = 449). We used a multiple linear regression model of DP concentrations to isolate the variabilities due to sampling date and population near the sampling site.

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Environmental measurement programs are often undertaken with the assumption that measurements at a given location will be comparable to others that would be observed at the same time in the immediate vicinity, but this assumption has seldom been tested. This paper does so. We discuss here the precision of atmospheric concentration measurements of persistent organic pollutants (POPs) near the North American Great Lakes-measurements that we have been conducting since 1994.

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Purpose: The use of ureteral stents for ureteral obstruction and after ureteroscopy can result in substantial deterioration in patient quality of life due to pain, frequency and urgency. We postulated that many stent related symptoms may be related to detrusor muscle spasm in and around the intramural ureter, and evaluated the effect of botulinum toxin type A (Botox) in patients with indwelling stents after ureteroscopy.

Materials And Methods: A total of 51 patients between December 2007 and March 2009 were enrolled in an institutional review board approved, prospective, randomized, single-blind study comparing botulinum toxin type A injection at a concentration of 10 U/ml to 3 locations around the ureteral orifice (30) vs no injection after unilateral ureteral stent insertion (21).

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Objectives: To compare the optics, performance, and durability of digital (DC) and fiberoptic (FC) cystoscopes.

Methods: In an office setting, we randomly assigned staff urologists to 1 of the 4 cystoscopes, the Gyrus-ACMI ICN-0564 (AD), Gyrus-ACMI ACN-2 (AF), Olympus CYF-V2 EndoEYE Cysto-Nephro Videoscope (OD), Olympus CYF-5 Cysto-Fiberscope (OF), to perform diagnostic or surveillance cystoscopy and stent removal. The documented metrics included a subjective surgeon assessment of cystoscope optics and function characteristics on a 10-point scale (1, poor to 10, excellent).

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Objectives: To compare helium and carbon dioxide gas insufflation for the creation of pneumocystis during bladder cryoablation in an effort to optimize the technique.

Methods: Nine pigs were divided into 3 groups. The pigs in groups 1, 2, and 3 underwent bladder cryoablation in a normal saline, carbon dioxide gas, and helium gas environment, respectively.

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Background And Purpose: Recent preclinical data have indicated that erythropoietin (Epo) can protect organs from ischemic damage. We evaluated the ability of Epo to protect the kidney from the effects of ischemia.

Methods: Thirty dogs underwent a laparoscopic nephrectomy and were allowed to recover for 2 weeks.

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This article focuses on the laparoscopic approaches to radical and partial nephrectomy for the managment of renal cell carcinoma and on the laparoscopic and endoscopic approaches for treating upper tract urothelial carcimoma. An in-depth discussion of treatment for transitional cell carcinoma is also presented.

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Purpose: Energy-based surgical devices (ESDs) are critical for maintaining hemostasis during laparoscopy; however, there are no studies that have evaluated the function of ESDs under different physiologic conditions. We evaluated the effect of intraluminal vessel content on bursting pressure (BP) after ligation with two ESDs: the Harmonic ACE and the LigaSure V.

Materials And Methods: Bursting trials were performed on the vasculature of 24 pigs.

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Objective: To assess the risk factors for haemorrhage and renal fracture associated with renal cryoablation.

Materials And Methods: In a porcine model, 120 cryoablations were administered in 26 pigs, with five groups of 24 ice-balls each; in groups 1 and 2 asynchronous cryoprobe activation was evaluated for the 1.47- and 3.

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Background And Purpose: In expanding our indications for cryoablation of renal cortical neoplasms, there was an increased morbidity with laparoscopic cryoablation. As such, we evaluated our single institution experience with laparoscopic renal cryoablation for complications and oncologic effectiveness as a function of tumor size.

Materials And Methods: We retrospectively evaluated our prospectively established urologic oncology database and identified 44 laparoscopic cryoablation procedures performed for the management of 51 renal masses.

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Objective: To assess surgeons' training and current understanding of existing energy-based surgical instrumentation (ESI), we disseminated an online questionnaire to urology residents, fellows and attending urologists.

Subjects And Methods: A two part 24-question survey was disseminated to 1000 urology residents, fellows and attending physicians. The first part of the questionnaire assessed the respondents' demographics and education about ESI; the second part evaluated the respondent's knowledge of surgical energy methods and ESI, and was stratified into nine basic- and six advanced-knowledge questions.

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The detection of incidental and asymptomatic renal cortical neoplasms has concomitantly increased with radiographic imaging use. The gold standard for treating small renal tumors includes open and laparoscopic partial nephrectomy. Ablative renal procedures intend to duplicate the excellent oncologic outcomes of partial nephrectomy, while decreasing complications and shortening hospitalization time and convalescence.

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The increased application of radiographic imaging has paralleled a simultaneous increase in the detection of incidental and asymptomatic renal neoplasms. The reference standard for treating small renal tumors includes open and laparoscopic partial nephrectomy. The primary objectives of ablative renal procedures are to duplicate the excellent oncologic outcomes of partial nephrectomy while decreasing patient morbidity and shortening hospitalization and overall convalescence.

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Objectives: There is little data available on the effects of energy-based surgical devices (ESD) on tissues other than arteries and veins. As such, we quantified the lateral thermal damage associated with contemporary ESD: the Harmonic ACE, a prototype bipolar device known as the Gyrus Trisector, the Harmonic LCS-C5, and the LigaSure V.

Methods: We divided 24 domestic pigs into 4 groups, 1 group for each ESD tested.

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Purpose: To compare the efficiency and cost effectiveness of a combined pneumatic and ultrasonic lithotrite (Lithoclast Ultra) and a standard ultrasonic lithotrite, (LUS-1) during percutaneous nephrolithotomy.

Materials And Methods: In a prospective randomized trial, 30 patients undergoing percutaneous nephrolithotomy (PCNL) were randomized to PCNL with either the combined pneumatic and ultrasonic lithotrite (PUL) or a standard ultrasonic lithotrite (SUL). Patient demographics, stone composition, location, pre- and post-operative stone burden, fragmentation rates, and device failures were compared.

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Objective: To characterize the physiological fatigue in bladder smooth muscles that can occur within 60 s of stimulation, which is closer to the duration of normal voiding.

Materials And Methods: Longitudinal and transverse strips of rat bladder were used; the muscles were mounted in an in vitro multi-muscle chamber, and the decline in contractile tension recorded during continuous electrical stimulation at frequencies of 5-30 Hz for 60 s. The effect of muscle length on fatigue was assessed by monitoring the decline in tension during 30 Hz stimulation at rest length, and at 60% and 100% stretched lengths of the bladder strips.

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Genital human papillomavirus (HPV) infection is the most common sexually transmitted disease. Each year 1 million new cases of genital warts are diagnosed, two thirds of which are in women. The estimated prevalence rate in the US population is 15 percent.

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A 32-year-old black man presented with two separate eruptions on his penis (Figure). He has had a 10-year history of asymptomatic 1-3 mm shiny papules on the shaft of his penis. He also has had one asymptomatic verrucous brown plaque 1.

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Complications following hallux valgus surgery can occur and are a frequent source of patient dissatisfaction. The treatment of these complications begins with careful preoperative planning to ensure that the chosen procedure is appropriate for the specific patient. When complications occur, treatment must also be individualized to address the symptoms of the patient.

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