RESUMO
Rising temperatures in the Arctic cause accelerated mass loss from the Greenland Ice Sheet and reduced sea ice cover. Tidewater outlet glaciers represent direct connections between glaciers and the ocean where melt rates at the ice-ocean interface are influenced by ocean temperature and circulation. However, few measurements exist near outlet glaciers from the northern coast towards the Arctic Ocean that has remained nearly permanently ice covered. Here we present hydrographic measurements along the terminus of a major retreating tidewater outlet glacier from Flade Isblink Ice Cap. We show that the region is characterized by a relatively large change of the seasonal freshwater content, corresponding to ~2 m of freshwater, and that solar heating during the short open water period results in surface layer temperatures above 1 °C. Observations of temperature and salinity supported that the outlet glacier is a floating ice shelf with near-glacial subsurface temperatures at the freezing point. Melting from the surface layer significantly influenced the ice foot morphology of the glacier terminus. Hence, melting of the tidewater outlet glacier was found to be critically dependent on the retreat of sea ice adjacent to the terminus and the duration of open water.
RESUMO
BACKGROUND AND PURPOSE: The endourologic community is in search of safer and efficient alternatives to conventional transurethral resection of the prostate (TURP). This research compared the efficacy of two transurethral resection techniques - conventional loop and rotoresection - in the surgical management of benign prostatic hyperplasia (BPH). PATIENTS AND METHODS: From January 2000 through December 2001, we randomized 128 BPH patients aged 55 to 74 years (average 61.4 +/- 2.7 years), all complaining of symptoms for prostatism for 1 to 14 years (average 4.5 +/- 1.5 years), to either transurethral rotoresection (TURotor; N = 58) or TURP (N = 70). The mean ages in the two groups were 67.53 +/- 7.21 years and 62.93 +/- 6.43 years, respectively. The diagnosis of BPH was made on the basis of patient history, International Prostate Symptom Score (IPSS), digital rectal examination, transrectal ultrasonography, uroflowmetry, and serum prostate specific antigen (PSA) concentration. Three months after surgery, we again measured the residual urine volume, uroflow, IPSS, and prostate size by ultrasonography. RESULTS: The TURotor took 30.1 +/- 10.2 minutes with an intraoperative blood loss of 130 +/- 25 mL. During the immediate postoperative period, an insignificant amount of blood was visible in the urine and irrigation fluid. We removed the catheter at 1.8 +/- 0.69 days. At 3 months' follow-up, the maximum uroflow rate (Q(max)) had increased to 19.87 +/- 6.77 mL/sec, and the residual urine volume had fallen to 38.75 +/- 18.84 mL. The average TURP lasted 42.1 +/- 13.2 minutes, or almost 30% longer than TURotor. The intraoperative blood loss averaged 21050 mL. The catheter was removed in 2.2 +/- 0.78 days. At 3 months, the Q(max) was 20.78 +/- 6.56 mL/sec, and the average amount of residual urine had fallen to 35.48 +/- 8.71 mL. CONCLUSION: Rotoresection is a promising alternative to conventional TURP because it affords almost bloodless, 30% faster removal of prostate tissue.
