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Liquefied natural gas (LNG) use as shipping fuel has increased in recent years. While LNG results in lower carbon dioxide (CO2) emissions as well as benefits in terms of air pollutants, the slip of unburned methane, the main component of LNG, has remained a concern. In this study, methane together with other climate warming agents, CO2 and black carbon (BC), as well as other emission compounds were characterized from 4-stroke low-pressure dual fuel engine on-board a newly build cruise ship utilizing LNG as well as marine gas oil (MGO). The brake specific methane slip was found to vary according to engine load, being 2.3–3.0 g/kWh at 54–80% loads, but increasing to 10 g/kWh at 25% load and 21 g/kWh at 12% load. The LNG combustion also resulted in higher formaldehyde emissions compared to MGO, but reduction in formaldehyde levels was observed over the SCR catalyst present in the exhaust line of the dual-fuel engine, without urea injection, suggesting it may provide a pathway for formaldehyde mitigation. In terms of particle emissions, LNG use reduced particle mass (PM) by 87–93% and BC by 94–99% compared to MGO combustion. Non-volatile particle number above 23 nm (PNnv,>23nm) and 10 nm (PNnv,>10nm) were reduced by 88–97% and 97–99%, except at lowest engine load where PNnv,>10nm increased by 26% compared to MGO utilization. When total greenhouse gas (GHG) emissions including CO2 and BC were considered, LNG use resulted in 13–15% lower GHG at high loads, but the benefit was undermined by the escaping methane at low load conditions. Following the engine activity profile during 8-months of vessel operation on the Mediterranean suggested, however, that in a diesel-electric cruise ship, low load conditions are used mainly during arrivals and departures from harbors, as the engine was operated at loads above 40% for 90% of the operation time. Weighted emission factor, representing the actual engine operation, resulted in methane slip of 2.8 g/kWh or 1.7% of the fuel use, which is below the value considered in the FuelEU Maritime. The results suggest that load specific methane slip, together with engine load profile should be considered when evaluating methane slip on vessel or fleet level.

Natural gas usage in the traffic and energy production sectors is a growing trend worldwide; thus, an assessment of its effects on air quality, human health and climate is required. Engine exhaust is a source of primary particulate emissions and secondary aerosol precursors, which both contribute to air quality and can cause adverse health effects. Technologies, such as cleaner engines or fuels, that produce less primary and secondary aerosols could potentially significantly decrease atmospheric particle concentrations and their adverse effects. In this study, we used a potential aerosol mass (PAM) chamber to investigate the secondary aerosol formation potential of natural gas engine exhaust. The PAM chamber was used with a constant UV-light voltage, which resulted in relatively long equivalent atmospheric ages of 11 days at most. The studied retro-fitted natural gas engine exhaust was observed to form secondary aerosol. The mass of the total aged particles, i.e., particle mass measured downstream of the PAM chamber, was 6–268 times as high as the mass of the emitted primary exhaust particles. The secondary organic aerosol (SOA) formation potential was measured to be 9–20 mg kgfuel−1. The total aged particles mainly consisted of organic matter, nitrate, sulfate and ammonium, with the fractions depending on exhaust after-treatment and the engine parameters used. Also, the volatility, composition and concentration of the total aged particles were found to depend on the engine operating mode, catalyst temperature and catalyst type. For example, a high catalyst temperature promoted the formation of sulfate particles, whereas a low catalyst temperature promoted nitrate formation. However, in particular, the concentration of nitrate needed a long time to stabilize – more than half an hour – which complicated the conclusions but also indicates the sensitivity of nitrate measurements on experimental parameters such as emission source and system temperatures. Sulfate was measured to have the highest evaporation temperature, and nitrate had the lowest. The evaporation temperature of ammonium depended on the fractions of nitrate and sulfate in the particles. The average volatility of the total aged particles was measured to be lower than that of primary particles, indicating better stability of the aged natural gas engine-emitted aerosol in the atmosphere. According to the results of this study, the exhaust of a natural gas engine equipped with a catalyst forms secondary aerosol when the atmospheric ages in a PAM chamber are several days long. The secondary aerosol matter has different physical characteristics from those of primary particulate emissions.

To comply with environmental regulations, ship operators may adopt exhaust after-treatment devices such as scrubbers or selective catalytic reduction (SCR). Beyond gaseous emission control, these technologies impact the exhaust particles emitted from marine engines to the atmosphere. This study characterizes comprehensively the chemical composition and physical properties of exhaust aerosol particles upstream and downstream a hybrid scrubber operating in open loop mode on-board a modern cruise ship. The study considers two engines, one equipped with SCR and both with scrubber, during engine load conditions of 75 % and 40 %, and the influence of marine gas oil (MGO) use in addition to heavy fuel oil (HFO). At least 4 different particle types were observed in the exhaust based on transmission electron microscopy (TEM) studies both upstream and downstream scrubber, and both scrubber and SCR affected the particle number size distribution (PSD). The geometric mean diameter (GMD) of the particles increased over scrubber both due to removal of nucleation mode particles and particle growth in the scrubber. The scrubber effectively decreased particle number (PN) and, also, non-volatile particles, but the effect depended on particle size and no significant decrease was observed in number of particles above 50 nm, typically comprising black carbon (BC) and in the case of HFO combustion, also asymmetrical metal containing particles. In addition to PN, concentrations of PAH compounds were reduced in the scrubber. The results may be further utilized when including the exhaust aerosol characteristics from ships applying scrubbers to emission inventories, as well as climate and air quality models., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Niina Kuittinen reports financial support was provided by K. F. and Maria Dunderberg Foundation. Niina Kuittinen reports financial support was provided by Merenkulun säätiö Foundation. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Shipping is the main source of anthropogenic particle emissions in large areas of the globe, influencing climate, air quality, and human health in open seas and coast lines. Here, we determined, by laboratory and on-board measurements of ship engine exhaust, fuel-specific particle number (PN) emissions for different fuels and desulfurization applied in shipping. The emission factors were compared to ship exhaust plume observations and, furthermore, exploited in the assessment of global PN emissions from shipping, utilizing the STEAM ship emission model. The results indicate that most particles in the fresh ship engine exhaust are in ultrafine particle size range. Shipping PN emissions are localized, especially close to coastal lines, but significant emissions also exist on open seas and oceans. The global annual PN produced by marine shipping was 1.2 × 10 28 (±0.34 × 10 28 ) particles in 2016, thus being of the same magnitude with total anthropogenic PN emissions in continental areas. The reduction potential of PN from shipping strongly depends on the adopted technology mix, and except wide adoption of natural gas or scrubbers, no significant decrease in global PN is expected if heavy fuel oil is mainly replaced by low sulfur residual fuels. The results imply that shipping remains as a significant source of anthropogenic PN emissions that should be considered in future climate and health impact models.

Particle emissions from marine traffic affect significantly air quality in coastal areas and the climate. The particle emissions were studied from a 1.4 MW marine engine operating on low-sulfur fuels natural gas (NG; dual-fuel with diesel pilot), marine gas oil (MGO) and marine diesel oil (MDO). The emitted particles were characterized with respect to particle number (PN) emission factors, PN size distribution down to nanometer scale (1.2-414 nm), volatility, electric charge, morphology, and elemental composition. The size distribution of fresh exhaust particles was bimodal for all the fuels, the nucleation mode highly dominating the soot mode. Total PN emission factors were 2.7 × 10 15 -7.1 × 10 15 #/kWh, the emission being the lowest with NG and the highest with MDO. Liquid fuel combustion generated 4-12 times higher soot mode particle emissions than the NG combustion, and the harbor-area-typical lower engine load (40%) caused higher total PN emissions than the higher load (85%). Nonvolatile particles consisted of nanosized fuel, and spherical lubricating oil core mode particles contained, e.g., calcium as well as agglomerated soot mode particles. Our results indicate the PN emissions from marine engines may remain relatively high regardless of fuel sulfur limits, mostly due to the nanosized particle emissions.

Background: It remains unclear whether patients with positive surgical margins or extracapsular extension benefit from adjuvant radiotherapy following radical prostatectomy., Objective: To compare the effectiveness and tolerability of adjuvant radiotherapy following radical prostatectomy., Design, Setting, and Participants: This was a randomised, open-label, parallel-group trial. A total of 250 patients were enrolled between April 2004 and October 2012 in eight Finnish hospitals, with pT2 with positive margins or pT3a, pN0, M0 cancer without seminal vesicle invasion., Intervention: A total of 126 patients received adjuvant radiotherapy at 66.6Gy., Outcome Measurements and Statistical Analysis: The primary endpoint was biochemical recurrence-free survival, which we analysed using the Kaplan-Meier method and Cox proportional hazard regression. Overall survival, cancer-specific survival, local recurrence, and adverse events were secondary endpoints., Results and Limitations: The median follow-up time for patients who were alive when the follow-up ended was 9.3yr in the adjuvant group and 8.6yr in the observation group. The 10-yr survival for biochemical recurrence was 82% in the adjuvant group and 61% in the observation group (hazard ratio [HR] 0.26 [95% confidence interval {CI} 0.14-0.48], p<0.001), and for overall survival 92% and 87%, respectively (HR 0.69 [95% CI 0.29-1.60], p=0.4). Two and four metastatic cancers occurred, respectively. Out of the 43 patients with biochemical recurrence in the observation group, 37 patients received salvage radiotherapy. In the adjuvant group, 56% experienced grade 3 adverse events, versus 40% in the observation group (p=0.016). Only one grade 4 adverse event occurred (adjuvant group). A limitation of this study was the number of patients., Conclusions: Adjuvant radiotherapy following radical prostatectomy is generally well tolerated and prolongs biochemical recurrence-free survival compared with radical prostatectomy alone in patients with positive margins or extracapsular extension., Patient Summary: Radiotherapy given immediately after prostate cancer surgery prolongs prostate-specific antigen progression-free survival, but causes more adverse events, when compared with surgery alone., (Copyright © 2019 European Association of Urology. Published by Elsevier B.V. All rights reserved.)

In order to meet stringent fuel sulfur limits, ships are increasingly utilizing new fuels or, alternatively, scrubbers to reduce sulfur emissions from the combustion of sulfur-rich heavy fuel oil. The effects of these methods on particle emissions are important, because particle emissions from shipping traffic are known to have both climatic and health effects. In this study, the effects of lower sulfur level liquid fuels, natural gas (NG), and exhaust scrubbers on particulate mass (PM) and nonvolatile particle number (PN greater than 23 nm) emissions were studied by measurements in laboratory tests and in use. The fuel change to lower sulfur level fuels or to NG and the use of scrubbers significantly decreased the PM emissions. However, this was not directly linked with nonvolatile PN emission reduction, which should be taken into consideration when discussing the health effects of emitted particles. The lowest PM and PN emissions were measured when utilizing NG as fuel, indicating that the use of NG could be one way to comply with up-coming regulations for inland waterway vessels. Low PN levels were associated with low elemental carbon. However, a simultaneously observed methane slip should be taken into consideration when evaluating the climatic impacts of NG-fueled engines.

To meet stringent NOx emission limits, selective catalytic reduction (SCR) is increasingly utilized in ships, likely also in combination with low-priced higher sulfur level fuels. In this study, the performance of SCR was studied by utilizing NOx, NH3, and particle measurements. Urea decomposition was studied with ammonia and isocyanic acid measurements and was found to be more effective with heavy fuel oil (HFO) than with light fuel oil. This is suggested to be explained by the metals found in HFO contributing to metal oxide particles catalyzing the hydrolysis reaction prior to SCR. At the exhaust temperature of 340 °C NOx reduction was 85-90%, while at lower temperatures the efficiency decreased. By increasing the catalyst loading, the low temperature behavior of the SCR was enhanced. The drawback of this, however, was the tendency of particle emissions (sulfate) to increase at higher temperatures with higher loaded catalysts. The particle size distribution results showed high amounts of nanoparticles (in 25-30 nm size), the formation of which SCR either increased or decreased. The findings of this work provide a better understanding of the usage of SCR in combination with a higher sulfur level fuel and also of ship particle emissions, which are a growing concern.

Purpose: In a previous retrospective analysis, cyclosporine A (CyA) was highly efficient in treating patients with interstitial cystitis. A prospective randomized study with this immunosuppressive agent was warranted. We compared CyA to pentosan polysulfate sodium (PPS) in patients with interstitial cystitis., Materials and Methods: A total of 64 patients with interstitial cystitis meeting the National Institute of Diabetes and Digestive and Kidney Diseases criteria were enrolled in a randomized prospective study. Patients were randomized in a 1:1 ratio to 1.5 mg/kg CyA twice daily (27 women, 5 men) or 100 mg PPS 3 times daily (26 women, 6 men) for a period of 6 months. The primary end point was daily micturition frequency, and secondary end points were mean and maximal voided volume, number of nocturia episodes, O'Leary-Sant symptom and problem indexes, visual analogue scale for pain, and subjective global response assessment., Results: CyA was superior to PPS in all clinical outcome parameters measured at 6 months. Micturition frequency in 24 hours was significantly reduced in the CyA arm compared to the PPS arm (-6.7 +/- 4.7 vs -2.0 +/- 5.1 times). The clinical response rate (according to global response assessment) was 75% for CyA compared to 19% for PPS (p <0.001). Although there were more adverse events in the CyA arm than in the PPS arm, 29 patients completed the 6-month followup in both groups., Conclusions: CyA is more effective than PPS in interstitial cystitis.

Purpose: Interstitial cystitis (IC) is a clinical condition occurring predominantly in women that is characterized by irritative voiding symptoms, including urinary frequency, urgency and pain. To our knowledge its etiology is unknown and little is known about its occurrence. We evaluated the prevalence of IC in women in Finland., Materials and Methods: A total of 2,000 participants were randomly selected from the Finnish population register. Urinary symptoms were evaluated using the validated O'Leary-Sant IC symptom and problem index questionnaire. Women with moderate or severe symptom scores (7 or higher) without any urinary tract infection during the last month were invited to undergo clinical examination., Results: Of the 1,331 respondents 32 had moderate or severe symptoms involving a suspicion of IC, of whom 21 underwent clinical evaluation. Three women were found to have probable IC and 4 had possible IC. Thus, the prevalence of clinically confirmed probable IC in women was 230/100.000 (95% CI 100 to 360) and that of possible/probable IC was 530/100.000 (95% CI 140 to 910). Considering the lack of information on 8 patients with urinary symptoms the corrected estimates were 300/100,000 (95% CI 120 to 770) and 680/100,000 women (95% CI 360 to 1,300), respectively., Conclusions: Our results based on a large and representative population, and clinically confirmed diagnoses indicate that IC is substantially more common than previously thought.

Objective: To determine the pharmacokinetics of oxybutynin and its main active metabolite, N-desethyloxybutynin, after multiple dosage (5 mg/30 ml three times daily) of intravesical oxybutynin formulation. Furthermore, to determine the efficacy and safety of intravesical oxybutynin in the symptomatic relief of urge incontinence or urgency in adult patients with detrusor hyperreflexia or instability., Material and Methods: Nine patients were randomly allocated to treatment with a special bladder instillation formulation of oxybutynin or placebo for two 14-day treatment periods in a double-blind, cross-over manner. The third, open study period was designed for pharmacokinetic purposes with all patients on the active drug. The pharmacokinetics was depicted by AUC0-24, Cmax, Cmin, and t(max), The efficacy was evaluated from the data collected from urinary voiding diaries and cystometries. The safety was measured by recording adverse events on questionnaires. Patients who were willing to continue with the intravesical oxybutynin treatment entered the 1-year extension part of the study., Results: Oxybutynin was absorbed from the bladder with a geometric mean Cmax of 9.4 ng/ml and AUC0-24 of 92 ng x h/ml. For N-desethyloxybutynin, the geometric mean Cmax was 14.4 ng/ml and AUC0-24 186 ng x h/ml. Elimination of the drug was protracted, as there were detectable serum concentrations of both oxybutynin and N-desethyloxybutynin even 24 hours post-dose. The mean number of toilet visits/day decreased from the baseline value of 6.9 to 5.7 during oxybutynin treatment, whereas during the placebo period the value increased to 7.4 (p = 0.022). It remained at the same decreased level during the one-year follow-up period., Conclusions: Oxybutynin is readily absorbed from the bladder after intravesical administration. The serum concentrations of oxybutynin after single 5 mg intravesical doses are at least as high as those reported after oral drug intake, but the parent drug/metabolite ratio is much higher after intravesical administration. The elimination of oxybutynin as well as its metabolite is prolonged after intravesical administration compared with that reported after oral drug intake. The mean number of daily toilet visits decreased significantly in the oxybutynin group.

Objective: To evaluate the results of Holmium:YAG (Ho:YAG) laser lithotripsy in the treatment of urinary stones., Material and Methods: Between 1993 and 1997, 59 patients with 85 urinary stones were treated with the Ho:YAG laser lithotripsy. Retrospective evaluation was done on the 64 procedures available, comprising 53 ureteric, 8 bladder, and 2 renal calculi, and one stone in a ureterocele., Results: The Ho:YAG laser fragmented all types of calculi. Of 38 patients, 29 (76%) with ureteric stones were stone-free and 7 (18%) had stone fragments smaller than 2 mm left 1-3 months after the lithotripsy, resulting in a total clinical success rate of 95%. The procedure caused four ureteric perforations. One ureteric stricture, after repeated treatments for a Steinstrasse formation, led to nephrectomy., Conclusions: The Ho:YAG laser was reliable and effective for most of the urinary stones. The largest stones in any location, and stones of hard composition, however, were treated with combined disintegration methods. Four minor ureteric perforations and one ureteric stricture were related to laser use.

Purpose: A randomized controlled study was done to evaluate the efficacy of the self-reinforced polyglycolic acid spiral stent compared to a suprapubic catheter, and combined suprapubic and indwelling catheters in the prevention of urinary retention after visual laser ablation of the prostate., Materials and Methods: We studied 72 men with benign prostatic hyperplasia who underwent placement of a suprapubic catheter and visual laser ablation of the prostate. In 27 men in group 1 the self-reinforced polyglycolic acid spiral stent was inserted into the prostatic urethra after visual laser ablation of the prostate, while 23 in group 2 received no other devices. In 22 men in group 3 an indwelling catheter was left in situ for an average of 6.5 days., Results: Voiding began 1 or 2 days postoperatively in 20 of 27 patients (median 1 day) in group 1, and 8 of 23 (median 6 days) in group 2. In 16 of 22 men in group 3 voiding began 1 or 2 days (median 6) after removal of the indwelling catheter. Improvements in patient weighted symptom score, mean peak urinary flow rate and post-void residual volume were significant (p < 0.001) at 6 months of followup in all groups. The overall infection rate was 30%., Conclusions: The self-reinforced polyglycolic acid spiral stent is superior to the suprapubic catheter alone, and to combined indwelling and suprapubic catheters for the treatment of postoperative urinary retention after laser therapy, offering possibilities for shorter catheterization time.

The cost and effectiveness of seventy-six consecutive percutaneous nephrolithotomy (PNL) procedures performed during the years 1990-1992, a sample of 425 ESWL patients with 675 treatments from 1991-1992, and 45 successive open pyelolithotomies (PL) performed before the advent of the new stone treatment techniques during the years 1981-1985, were studied for each of the treatment modalities. The costs were counted per patient and based on the cumulative charge of the procedures, cost for in-patient care, and treatment of additional procedures and operatively treated complications. The results showed that the great majority of ESWL patients were treated at a low cost and with few additional procedures and complications compared to PNL, particularly, when stones smaller than 20 mm were treated. Considering all the patients, the cumulative mean hospital cost per patient without the cost for the follow-up was as follows, FIM (pound): PL 33860(4200), PNL 63360(7860), and ESWL 17430(2160). The remarkable number of additional and auxiliary measures (including the pre- and post-operative ESWL procedures) resulted in considerable extra costs for the PNL patients until they were rendered stone-free. Another series comprising 42 successive patients with 48 stone basket procedures (SB) from the years 1981-1985 was retrospectively compared to 42 patients with 50 ureteroscopic stone extractions (URS) between January 1985 and April 1988 before the beginning of the ESWL practice in Finland as well as to 54 patients with 79 ESWL treatments for a lower ureteric stone during the years 1991-1992. The stone-free status after the three procedures until one month was 71, 66, and 60%, with no statistically significant difference. In the group of lower ureteric stones the cumulative mean hospital cost per patient was as follows, FIM (pound): SB 19520(2420), URS 17750(2200), and ESWL 17810(2210). Also in the treatment of lower ureteric stones, ESWL is an equally cost-effective method representing an alternative worth consideration, particularly for patients preferring a minimally invasive urinary stone treatment.

Kidneys of 35 renal stone patients treated with percutaneous nephrolithotomy (PNL) were examined at 12-36 months (mean 23 months) after the procedure by plain radiography (PR), conventional linear tomography (LT), computed tomography (CT), and ultrasonography (US) to find out the long-term stone-free rate as well as the accuracy of these imaging methods to detect residual or recurrent renal stones. The present series included 36 kidneys with a 56% postoperative stone-free status examined by plain radiography and a 58% one examined by linear tomography at 12-36 months. CT showed 47% and US 72% of the kidneys to be stone-free, respectively. The sensitivity of CT was superior to plain radiography (P < 0.05), linear tomography (P < 0.05) or US (P < 0.001) in the detection of residual or recurrent stones after percutaneous nephrolithotomy analyzed statistically by McNemar's test. In the same group of 35 patients, which consisted of the above 36 postoperative kidneys together with 19 contralateral kidneys, a total of 55 kidneys were evaluated by the above methods, revealing 56 stones in 31 kidneys. Of these stones 95% were detected by CT, 70% by plain radiography, 68% by linear tomography, and 32% by renal US. Of the 55 kidneys, 14 contained 20 stone fragments smaller than 3 mm, and 26 kidneys carried 43 concrements smaller than 6 mm. The sensitivities of the four imaging methods in the detection of these small fragments were as follows: plain radiography 60% and 60%, linear tomography 55% and 58%, CT 95% and 93%, and US 15% and 26%.(ABSTRACT TRUNCATED AT 250 WORDS)

A total of 1641 ESWL-treatments were performed in 948 patients at Helsinki University Central Hospital between June 1989 and December 1991. In a series of 816 patients and 1287 treatments with data available 681 (76.4%) stones were located in the kidney, 208 (23.3%) in the ureter, and three (0.3%) in the urinary bladder. Auxiliary procedures were performed in 156 (19.1%) and repeated treatments in 300 (36.8%) patients. The most common complication was intensive pain during the procedure in 138 (16.9%) patients. The first 139 patients were followed until six months after their last ESWL-procedure. The six-month stone-free rates of renal and ureteric stones of these patients were 67.4% and 86.7%, respectively. The overall six-month clearance rate was 72.4%.

Eighty ureterorenoscopies (URS) were performed for stone removal in 67 patients between January 1985 and April 1988. The success rates for stone removal were 54% in the lower third of the ureter, 70% in the middle third, 38% in the upper third, and 33% in the renal pelvis. The overall success rate was 42%. Open ureterolithotomy was performed after failed ureteroscopy nine times. There were two perforations of the ureter: one by the hook of the forceps and the other by the dormia basket. No significant late complications occurred in 51 patients after six to 36 months postoperatively. At the moment ureteroscopy is of value particularly in the treatment of lower or middle ureteric stones.

Fifty-four percutaneous nephrolithotomy (PNL) procedures were performed in 41 patients between May 1986 and December 1987. Six patients required more than one procedure and there was one failure which was treated by open ureterolithotomy. Most of the stones were initially found in the pelvicalyceal system, one in the lower third and nine in the middle or upper third of the ureter. There were five significant complications: one "steinstrasse" (accumulation of stone fragments in the distal ureter after the procedure), one massive perirenal haematoma, one intramural perforation by a ureteric catheter and two extravasations of irrigation fluid one of which necessitated intensive care. Most of the renal and upper ureteric stones have now been successfully removed percutaneously with good patient tolerance.