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This letter presents a wideband high gain substrate integrated waveguide horn antenna (SIWHA) loaded with half Maxwell fish‐eye (HMFE) fabricated by 3‐D‐Printing. The impedance bandwidth of the SIWHA is narrow, mainly caused by the discontinuity between the substrate with the air. By introducing the HMFE and a match layer between the SIWHA with HMFE, the impedance continuity can be realized, which can not only improve the impedance bandwidth but also enhance the antenna gain. Experimental results show that the proposed antenna can achieve more than 6 dBi gain and 60.9% relative impedance bandwidth with reflection coefficients lower than −10 dB. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy and safety of pulmonary rehabilitation for exercise tolerance and quality of life improvement in idiopathic pulmonary fibrosis. Methods: We searched PubMed, Cochrane Library, Embase, Web of Science, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, Wanfang Database, and Chongqing VIP for randomized controlled trials that compared pulmonary rehabilitation with usual care for idiopathic pulmonary fibrosis. The risk of bias and certainty of evidence were assessed using Cochrane Collaboration's Risk of Bias tool and the Grading of Recommendations, Assessment, Development and Evaluation criteria. Results: Eleven trials in total with 549 participants. Compared with usual care, pulmonary rehabilitation significantly increased 6-minute walking distance (mean difference: 35.2m, 95% confidence intervals: 25.4m–44.9m; ten trials; 447 participants; moderate), decreased the St George's Respiratory Questionnaire total scores (mean difference: −9.11, 95% confidence intervals: −10.78 to −7.43; six trials; 303 participants; moderate), and reduced the modified Medical Research Council scores were lower (mean difference: −0.76, 95% confidence intervals: −1.25 to −0.27; three trials; 196 participants; low). Improvements were noted in forced vital capacity percent-predicted (mean difference: 4.88, 95% confidence intervals: 2.67 to 7.10; four trials; 214 participants; moderate) and diffusing capacity for carbon monoxide (mean difference: 4.71, 95% confidence intervals: 0.96 to 8.46; six trials; 358 participants; low). Conclusions: Pulmonary rehabilitation may significantly improve exercise tolerance and quality of life in idiopathic pulmonary fibrosis patients, but the quality of evidence was low to moderate. Large sample, multicenter, randomized controlled trials are needed to verify the efficacy and safety of pulmonary rehabilitation. [ABSTRACT FROM AUTHOR]

The transition metal-modified VWTi structural catalysts hold great promise for simultaneously removing nitrogen oxides (NOx) and volatile organic compounds (VOCs) from industrial flue gases. A series of Cu@VWTi catalysts were prepared to investigate their synergistic low-temperature removal performance towards NO and typical VOCs, including toluene, benzene, chlorobenzene (CB), p-chlorotoluene (p-CT), and dichloromethane (DCM). The copper-enhanced samples prepared via ultrasound-assisted impregnation exhibited irregular globular and varying crystallinity. The catalysts displayed a typical anatase crystal structure with high TiO 2 content or high dispersion of V and W species along with a certain adjustment effect on the morphology. Various controlling factors affecting the synergistic removal of NO and VOCs were evaluated. It was observed that the presence of VOCs in flue gas has weak impact on NO removal, except for the waste incineration using the Cu@VWTi catalyst. However, a high initial NO concentration had an adverse effect on VOCs removal. Impressively, the optimized copper-doped catalyst (5 wt% Cu loaded of smelting plant and coal-fired power plant used catalyst) exhibited excellent performance for p-CT, toluene and DCM removal of 95.0%, 99.6% and 100% at 300 °C, respectively. The toluene and p-CT conversion efficiencies were highest over the catalyst used in the smelting plant after Cu loading, surpassing the benzene conversion efficiency. Cu@VWTi demonstrated excellent performance for p-CT, toluene, and DCM removal at 250 °C. Although 5 wt% Cu loading on the catalysts significantly enhanced the stability and anti-jamming of VOCs removal, as well as their tolerance to both SO 2 and water vapor. The enhanced mechanism of Cu decoration attributed to the enhanced intensity of acid sites and the stable relative proportion of O ads /O latt species in the used 5% Cu loaded catalyst due to the redox cycles of Cu and V species. Compared with Brønsted acid, which primarily adsorbs NH4+, Lewis acid mainly adsorbs gas phase acid and forms coordinated NH 3 in gas phase. The bonding between toluene and the Cu site was enhanced with an adsorption energy of −130.9 kJ mol−1, as well as the cracking adsorption of the CH 2 Cl 2 on the Ti site with a bonding energy of −436.7 kJ mol−1, both indicating strong chemical adsorption. The first step of dechlorination and demethylation was thermodynamically and kinetically favorable for DCM and toluene decomposition. [Display omitted] • Cu@VWTi catalyst endorsed prospect for the simultaneous removal of NO/VOCs. • Cu@VWTi deliver excellent performance for p-CT, toluene, and DCM removal at 250 °C. • Cu-doping enhanced resistance to interference from SO 2 /H 2 O in typical VOCs removal. • Strong adsorbed acidic and unsaturated coordinate bond on catalyst surface was enhanced. • Dechlorination and demethylation process was favorable for DCM/toluene decomposition. [ABSTRACT FROM AUTHOR]

• We propose the GDM to partition the sample space for improving the discriminability of the scene-specific object detector. • We propose the online gradual optimization procedure to automatically improve the performance of the GDM-based detector. • We propose a self-learning framework to train the GDM-based detector by marking several bounding boxes in the first frame. One object class may show large variations due to diverse illuminations, backgrounds, and camera viewpoints in the multi-scene object detection task. Traditional object detection methods generally perform poorly under unconstrained video environments. To address this problem, many modern approaches provide deep hierarchical appearance representations for object detection. Most of these methods require time-consuming training procedures on large manually annotated sample sets. In this paper, we propose a self-learning object detection framework to resolve the multi-scene detection problem in a bottom-up manner. A scene-specific objector is obtained from an autonomous learning process triggered by marking several bounding boxes around an object in the first video frame via a mouse. Here, artificially labeled training data or generic detectors are not needed. This learning process is conveniently replicated many times in different surveillance scenarios and produces scene-specific detectors from various camera viewpoints. Obviously, the initial scene-specific detector, initialized by several bounding boxes, exhibits poor detection performance and is difficult to be improved by traditional online learning algorithms. Consequently, we propose the Generative-Discriminative model (GDM) based detection method to partition detection response space and assign each partition an individual descriptor that progressively achieves high classification accuracy. Online gradual optimization process is proposed to optimize the Generative-Discriminative model and focus on those hard samples lying near the decision boundary. Experimental results on nine video datasets show that our approach achieves comparable performance to that of robust supervised methods, and outperforms state-of-the-art scene-specific object detection methods under varying imaging conditions. [ABSTRACT FROM AUTHOR]

In this paper, a wide-range leaky-wave antenna with fast scanning rate and open-stopband (OSB) suppression based on microstrip spoof surface plasmon polaritons (MSSPPs) is proposed. First, the high-scanning-rate theory is analyzed. And based on the theory, the MSSPPs is used to radiate the fan beam rather than quasi-omnidirectional beam. In order to suppress the OSB, a capacitive slot is introduced using the proposed method of impedance matching. The prototype of the proposed antenna is fabricated and the measured results show that the antenna has 140° scanning range from −72° to 68° with the scanning rate of 8.8 and reflection coefficient lower than −10 dB in 8.7–10.2 GHz. [ABSTRACT FROM AUTHOR]

Objective: The prognosis for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is not optimistic, and severe AECOPD leads to an increased risk of mortality. Prediction models help distinguish between high‐ and low‐risk groups. At present, many prediction models have been established and validated, which need to be systematically reviewed to screen out more suitable models that can be used in the clinic and provide evidence for future research. Methods: We searched PubMed, EMBASE, Cochrane Library and Web of Science databases for studies on risk models for AECOPD mortality from their inception to 10 April 2022. The risk of bias was assessed using the prediction model risk of bias assessment tool (PROBAST). Stata software (version 16) was used to synthesize the C‐statistics for each model. Results: A total of 37 studies were included. The development of risk prediction models for mortality in patients with AECOPD was described in 26 articles, in which the most common predictors were age (n = 17), dyspnea grade (n = 11), altered mental status (n = 8), pneumonia (n = 6) and blood urea nitrogen (BUN, n = 6). The remaining 11 articles only externally validated existing models. All 37 studies were evaluated at a high risk of bias using PROBAST. We performed a meta‐analysis of five models included in 15 studies. DECAF (dyspnoea, eosinopenia, consolidation, acidemia and atrial fibrillation) performed well in predicting in‐hospital death [C‐statistic = 0.91, 95% confidence interval (CI): 0.83, 0.98] and 90‐day death [C‐statistic = 0.76, 95% CI: 0.69, 0.82] and CURB‐65 (confusion, urea, respiratory rate, blood pressure and age) performed well in predicting 30‐day death [C‐statistic = 0.74, 95% CI: 0.70, 0.77]. Conclusions: This study provides information on the characteristics, performance and risk of bias of a risk model for AECOPD mortality. This pooled analysis of the present study suggests that the DECAF performs well in predicting in‐hospital and 90‐day deaths. Yet, external validation in different populations is still needed to prove this performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • The generation characteristics of ABS/AS under non-catalytic conditions were investigated. • SO 3 and NH 3 enhanced ABS/AS generation and deposition. • The initial deposition temperature of ABS/AS is exponentially correlated with the product of SO 3 and NH 3 concentration. • Liquid ABS deposited firstly, the mixture of H 2 O, ABS and H 2 SO 4 or AS and (NH 4) 3 H(SO 4) 2 deposited at low temperature. The generation and deposition of ammonium bisulfate (ABS) in flue gas caused serious blockage and corrosion to the air preheater, which seriously affect the safe and economic operation of coal-fired power plants. The generation and deposition of ABS/ammonium sulfate (AS) under non-catalytic conditions were studied on a simulated air preheater test bench, and FT-IR and XRD tests were performed to characterize the products under different conditions. Experimental results show that the generation of ABS/AS is complicated and controlled by the concentration of SO 3 and NH 3 , the ratio of SO 3 to NH 3 (SO 3 /NH 3) and deposition temperature. Under the same SO 3 conditions, ABS/AS generation rate under different SO 3 /NH 3 conditions is 1:2 > 2:1 > 1:1. The initial deposition temperature of ABS/AS will increase with the corresponding increase of SO 3 and NH 3 concentration, and is exponentially correlated with the product of SO 3 and NH 3 concentration in flue gas. In the temperature range 390–223 °C, ABS generated and deposited under all conditions, and in the temperature range 223–131 °C, the mixture of H 2 O, H 2 SO 4 , and ABS generated and deposited when SO 3 /NH 3 is 2:1, and AS with a small amount of (NH 4) 3 H(SO 4) 2 generated and deposited when SO 3 /NH 3 is 1:1 and 1:2. [ABSTRACT FROM AUTHOR]

In this article, a broadband dual circularly polarized (CP) antenna with simple structure and high gain is designed. A metal ridge septum with the shape of the cascade of a rectangle and a triangle is embedded into the square waveguide to excite CP wave, which is presented through analysis and simulation. By feeding the antenna at the two positions with respect to the symmetrical position of the septum, it can form the right‐handed circularly polarized (RHCP) and left‐handed circularly polarized (LHCP) wave, respectively. To verify the design, a prototype of the antenna is fabricated and measured. The measured and simulated results coincide with each other. According to the simulation and measurement, the designed antenna can work well within a relative bandwidth of 64% from 8.5 to 16.5 GHz. The proposed dual CP antenna has the simple configuration and good performance, and it can be a good candidate antenna for the broadband communication system. [ABSTRACT FROM AUTHOR]

Abstract In this paper, a 600 MWe Babcock & Wilcox boiler is selected as the research object. Numerical simulation and field experiments have been applied to this study under original and new combustion systems. The new approach mainly involves changing the operation mode of swirl burner, rearranging secondary air, and employing separated over-fire air. Numerical results showed that NO x emissions and the unburned combustible in flue dust decrease with the arrangement of the swirl burner changing from co-rotating mode to counter-rotating one. Consequently, counter-rotating mode of adjacent burners was chosen as the optimized arrangement. The introduction of separated over-fire air resulted in a remarkably reduction of the NO x emissions, which reduced from 1085 mg/m3 to 547 mg/m3. With increase of the distance between separated over-fire air and arch from 0.5 m to 3.0 m, NO x emissions changed slightly and the unburned combustible in flue dust were not greatly affected. When the distance continued increase to 6.0 m, NOx generation was suppressed and boiler efficiency declined. Considering the economic efficiency and NOx emissions reduction, the optimal sofa position is 3.0 m above the arch. In situ measurement results are consistent with the modelling predictions This work provides a feasible and economic approach for Babcock & Wilcox down-fired boilers to achieve high efficiency and low pollutant emissions. Highlights • Study the effects of burner rearrangement on low-nitrogen combustion. • Accurate calculate carbon content in fly ash by using CBK model. • Optimize the combustion system based on numerical simulations. • NOx at furnace exit decrease from 1085 mg/m3 to 547 mg/m3 by introduce SOFA. [ABSTRACT FROM AUTHOR]

Cerebral ischemic stroke is a high-risk disease and imposes heavy burdens on patients in china. Acupuncture has been used for thousands of years to treat motor dysfunction, cognitive disorder and language barrier caused by cerebral ischemic stroke. Acupoint lines, vertex middle line and anterior oblique line of vertex temple, are always employed to treat cerebral ischemic stroke. However, the mechanism of the two acupoint lines in relieving cerebral ischemic stroke needs further exploration. In the present study, scalp acupuncture treatment alleviated the motor dysfunction, brain damage, and cell death induced by middle cerebral artery occlusion (MCAO) in rats. Proteomics analysis and ultrastructure observation indicated that endoplasmic reticulum and lysosomes might involve in the mechanism of the scalp acupuncture treatment in suppressing MCAO-triggered neural deficits. Effect of the scalp acupuncture treatment on ER stress was then investigated and found that the activation of ER stress mediators, including PERK, IRE1, and ATF6, was downregulated after the scalp acupuncture treatment. Co-localisation analysis of KDEL and CD63 showed that the engulfment of ER fragments by lysosomes was accelerated by the scalp acupuncture treatment. Moreover, expression of pro-apoptotic protein CHOP, phosphorylated-JNK, cleaved capases-3 and -9 also decreased after the scalp acupuncture. In conclusion, the present study showed that scalp acupuncture of vertex middle line and anterior oblique line of vertex temple may alleviate cerebral ischemic stroke by inhibiting ER stress-accelerated apoptosis. [ABSTRACT FROM AUTHOR]

SBRT is an increasingly popular treatment for localized prostate cancer, though considerable variation in technical approach is common and optimal dose constraints are uncertain. In this study, we sought to identify dosimetric and patient-related predictors of acute rectal toxicity. Patients included in this study were treated with prostate SBRT on a prospective institutional protocol. Physician-graded toxicity and patient-reported outcomes were captured at one week, one month, and three months following SBRT. DVH data were extracted and converted into relative volume differential DVHs for NTCP modeling. Patient- and disease-related covariates along with NTCP model predictions were independently tested for significant association with physician-graded toxicity or a decline in bowel-related QoL. A multivariate model was constructed using forward selection, and significant parameter cutoff values were obtained with Fischer's exact test to group patients by risk of developing physician-graded toxicity or detriments in patient-reported QoL. One hundred and three patients treated for localized prostate cancer with SBRT were included in our analysis. 52% of patients experienced a clinically significant decline in bowel-related QOL within 1 week of completion of treatment, while only 27.5% of patients developed grade 2+ physician-graded rectal toxicity. Sequential feature selection multivariate logistic regression identified rectal V22.5 Gy (p = 0.001) and D19% (p = 0.001) as independent predictors of clinically significant toxicity, while rectal V20Gy (p = 0.004) and D25.3% (p = 0.007) were independently correlated with physician-graded toxicity. Global multivariate step-wise logistic regression identified only D19% (p = 0.001) and V20Gy (p = 0.004) as independent predictors of acute bowel bother or physician-graded rectal toxicity respectively. Moderate doses to large rectal volumes, D19% and V20Gy, were associated with an increased incidence of a clinically significant decrease in patient-reported bowel QOL and physician-scored grade 2+ rectal toxicity, respectively. These dosimetric parameters may help practitioners mitigate acute toxicity in patients treated with prostate SBRT. [ABSTRACT FROM AUTHOR]

A fast and efficient method is proposed in this letter to characterize the dielectric permittivity of thin‐film materials. The measuring system is based on a TE103 rectangular split‐cavity resonator operating at around 10 GHz, which has the advantage of providing nondestructive measurements while maintaining a high level of accuracy. The thin‐film materials under test can be directly inserted in the split without being processed in a specific shape. Different dielectric materials are tested using this method. And the theoretical derivations and experimental measurements have been performed to confirm the validity and effectiveness of this approach. [ABSTRACT FROM AUTHOR]

[Display omitted] • The deposition and transformation of ammonium bisulfate (ABS) on fly ash under variable temperature conditions was investigated. • Fly ash enhanced ABS deposition by trapping and absorbing effects. • ABS deposition is positively correlated with the product of SO 3 and NH 3. • Along the flow direction of flue gas in the air preheater, the deposited products will gradually convert from ABS to the mixture of ABS and H 2 SO 4. • ABS will convert into sulfate with higher decomposition temperature on fly ash. Ammonium bisulfate (ABS) aggravates the corrosion and plugging of air preheaters, resulting in unplanned outages and expensive cleaning. Understanding its deposition and transformation process is important for the development of ABS control strategies. A multistage temperature control system was built to simulate the temperature gradient in the air preheater and the deposition and transformation of ABS in the presence of fly ash were studied using Fourier-transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and thermogravimetry. The presence of fly ash increases both the deposition amount and the temperature of ABS in the 25–200 ppm SO 3 concentration range; the initial ABS deposition temperature is between 202 and 290 ℃ and most likely occurs in the 230–250 ℃ range. The main product was ABS, and its formation temperature was much higher than the deposition temperature observed in the experiment. In the 224–180 ℃ range, the products gradually changed from ABS to sulfuric droplets. Fly ash has trapping and adsorbing effects on the gas-phase ABS in flue gas, and more ABS is captured at high temperatures owing to the higher concentrations of reactants. ABS deposition leads to the accumulation and adhesion of fly ash particles and reacts with the fly ash to convert it into a variety of ammonium salts and sulfates with higher decomposition temperatures. Compared with the sulfate formed after the deposition of sulfuric acid droplets, the sulfate formed by ABS conversion had a lower relative decomposition temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] • The performance and mechanism of CO 2 capture by amine blended solvents were reviewed. • The technology of simultaneous removal of CO 2 /NOx/SO 2 by ammonia was discussed. • The industrial challenges during CO 2 capture were summarized. • The specific directions have been proposed for the future development. Absorption/regeneration systems based on chemical solutions are considered a more appropriate option for post-combustion CO 2 capture, with amine solvents being the most commonly utilized. First, this paper provides a systematic review of the mechanisms and performance of CO 2 capture by blended solvents of amine–amine, amine-organic solutions, amine-inorganic solutions, and amine-ionic liquids. Furthermore, some process modifications that can reduce energy consumption and amine degradation during CO 2 capture are discussed. As a promising and challenging absorbent, aqueous ammonia shows potential for simultaneous removal of CO 2 /NOx/SO 2 , producing valuable byproducts like ammonium sulphate and ammonium nitrate fertilizers. Therefore, the current development of ammonia scrubbing techniques for CO 2 capture and simultaneous removal of CO 2 /NOx/SO 2 is subsequently reviewed in terms of reaction mechanisms, process modifications, and application challenges. Finally, specific directions have been proposed for the future development of amine and aqueous ammonia scrubbing techniques, which are expected to provide meaningful guidance for CO 2 capture by chemical absorption. [ABSTRACT FROM AUTHOR]

As the most produced thermoplastic after polyolefins, an urgent issue for polyesters is to improve their environmentally friendliness in processing, application, and recycling. However, the performance of polyesters significantly deteriorates in the above stages. This work breaks through the difficulties when applying traditional polyesters by the green in situ construction of a novel covalent adaptable network, which has an ultrafast exchange reaction rate attributed to the synergistic catalytic effect of neighboring group participation (NGP) and the tertiary amine structure. This polyester-based vitrimer shows advanced performance in repairability (fast self-healing), foamability (matching fast CO2 diffusion) and recyclability (efficient reprocessing), due to the ultrafast exchange reaction rate in the system. The obtained vitrimer then possesses excellent self-healing behavior, as the damage was recovered within 32 min at 245 °C, possesses great foamability, as the foam prepared via green scCO2 foaming technology has a density as low as 0.039 g cm−3 and has a thermal conductivity as low as 28 mW/(m K)−1, and, meanwhile, possesses an advanced reprocessing ability without performance loss. Furthermore, the proposed strategy shortens the preparation time of the vitrimer to 3.5 min, providing a practical green method for the continuous process and industrial production of the polyester vitrimer via the synergistic catalytic effect of NGP and the tertiary amine structure, which is also constructive to the improved performance, environmentally friendly upcycling, and green application of the polyester vitrimer. [ABSTRACT FROM AUTHOR]

Background and purpose This study is to determine if the overlap-volume histogram (OVH)-driven planning methodology can be adapted to robotic SBRT (CyberKnife Robotic Radiosurgery System) to further minimize the bladder and rectal doses achieved in plans manually-created by clinical planners. Methods and materials A database containing clinically-delivered, robotic SBRT plans (7.25 Gy/fraction in 36.25 Gy) of 425 patients with localized prostate cancer was used as a cohort to establish an organ’s distance-to-dose model. The OVH-driven planning methodology was refined by adding the PTV volume factor to counter the target’s dose fall-off effect and incorporated into Multiplan to automate SBRT planning. For validation, automated plans (APs) for 12 new patients were generated, and their achieved dose/volume values were compared to the corresponding manually-created, clinically-delivered plans (CPs). A two-sided, Wilcoxon rank-sum test was used for statistical comparison with a significance level of p < 0.05. Results PTV’s V (36.25 Gy) was comparable: 95.6% in CPs comparing to 95.1% in APs ( p = 0.2). On average, the refined approach lowered V (18.12 Gy) to the bladder and rectum by 8.2% ( p < 0.05) and 6.4% ( p = 0.14). A physician confirmed APs were clinically acceptable. Conclusions The improvements in APs could further reduce toxicities observed in SBRT for organ-confined prostate cancer. [ABSTRACT FROM AUTHOR]

In this letter, a simple approach to design a reconfigurable feeding network (RFN) for antenna array beam scanning is presented. By combining a 3 dB power divider and a reconfigurable delay line group (RDLG), the two output signals with 2 m+n sets of uniformly distributed phase gradients (PGs) can be obtained. And by adopting multi two-output RFNs and multi-stage design, a RFN for generating 2 m+n continuously distributed beams is constructed. For verifying the design method, a microstrip four-output RFN for generating four scanning beams is implemented, fabricated and measured. The measured results are consistent with the theoretical analysis, which provides the validity of the design. And the design of the RFN can be used as a candidate of the feeding network for antenna array beam scanning. [ABSTRACT FROM AUTHOR]

Abstract The performance of selective catalyst reduction systems highly depends on the degree of mixing between NH 3 and NO x and the flow uniformity of velocity and concentration, which are sensitive to several parameters such as the installment of gate leafs, a hybrid grid, a straightener, and the ammonia injection method. In this work, computational fluid dynamics was applied to investigate these parameters in heat recovery steam generators. Performance of gate leafs and a new type of hybrid grid was considered. Analyses showed that gate leafs significantly improved the uniformity of velocity distribution and that the new type of hybrid grid improved the uniformity of concentration distribution. The velocity relative standard deviation decreased from 19.6% to 5.4%, and the concentration relative standard deviation decreased from 70% to 12.7%. Experiments also qualitatively confirmed the reliability of simulation results. Moreover, the hybrid grid was optimized with different structures. Results indicated that a 30° crossed angle could obtain a better mixing between NH 3 and NO x with a slight decrease in pressure. In addition, an optimal injection method of the ammonia injection grid was designed, and it was helpful in conducting the field operation. The relationship between the thickness of the straightener and the incident angle at the entrance of catalyst layer was discussed. Highlights • Performance of gate leafs and a new type of hybrid grid was considered in heat recovery steam generators. • Gate leafs significantly improved the uniformity of velocity distribution. • New type of hybrid grid improved the uniformity of concentration distribution. • Hybrid grid with a 30° crossed angle could obtain a better mixing between NH 3 and NO x. • An optimal injection method of the ammonia injection grid was designed. [ABSTRACT FROM AUTHOR]

Background.Late urinary symptom flare has been shown to occur in a small subset of men treated with ultra- hypofractionated stereotactic body radiotherapy (SBRT) for prostate cancer. The purpose of this study was to use normal tissue complication probability modeling in an effort to derive SBRT specific dosimetric predictor's of late urinary flare. Material and methods.Two hundred and sixteen men were treated for localized prostate cancer using ultra- hypofractionated SBRT. A dose of 35–36.25 Gy in 5 fractions was delivered to the prostate and proximal seminal vesicles. Functional surveys were conducted before and after treatment to assess late toxicity. Phenomenologic NTCP models were fit to bladder DVHs and late urinary flare outcomes using maximum likelihood estimation. Results.Twenty-nine patients experienced late urinary flare within two years of completion of treatment. Fitting of bladder DVH data to a Lyman NTCP model resulted in parameter estimates of m, TD50, and n of 0.19 (0–0.47), 38.7 Gy (31.1–46.4), and 0.13 (-0.14–0.41), respectively. Subsequent fit to a hottest volume probit model revealed a significant association of late urinary flare with dose to the hottest 12.7% of bladder volume. Multivariate analysis resulted in a final model that included patient age and hottest volume probit model predictions. Kaplan-Meier analysis demonstrated a two-year urinary flare free survival of 95.7% in patients 65 years or older with a bladder D12.7% of 33.5 Gy or less, compared to 74.5% in patients meeting none of these criteria. Conclusion.NTCP modeling of late urinary flare after ultra-hypofractionated prostate SBRT demonstrates a relatively small volume effect for dose to the bladder, suggesting that reduction of volume receiving elevated dose will result in decreased incidence of late urinary toxicity. Future studies will be needed to examine the impact of dose to other potential sources of late genitourinary toxicity. [ABSTRACT FROM PUBLISHER]

The article presents a study for predictors of acute urinary symptom flare following stereotactic body radiation therapy (SBRT) in the definitive treatment of localized prostate cancer. Topics include use of SRBT in management of localized prostate cancer; relationship between the prostate, urethra, and the role of radiation dose to other genitourinary organs-at-risk; and understanding the nature of acute urinary morbidity caused by prostate SBRT.

Background. Stereotactic body radiotherapy (SBRT) has emerged as an effective treatment for localized prostate cancer. However, prostate specific antigen (PSA) kinetics after prostate SBRT have not been well characterized. The purpose of this study was to analyze the trend in PSA decline following robotic SBRT from a prospective cohort of patients. Material and methods. In total 175 patients were treated definitively for localized prostate cancer to a dose of 35-36.25 Gy in 5 fractions using robotic SBRT in the absence of androgen deprivation therapy (ADT). PSA and testosterone were collected at regular intervals following treatment and patients were assessed for biochemical failure and benign PSA bounce. A PSA nadir threshold of 0.5 ng/ml was used as a predictor of long-term disease-free survival. Multivariate logistic regression was used to assess the effect of disease specific covariates on the likelihood of achieving a PSA nadir less than threshold. PSA kinetics were analyzed a multi-component exponential model accounting for benign and malignant sources of PSA. Results and conclusion. At a median follow-up of 3 years, 70% of patients achieved a PSA nadir below 0.5 ng/ml with a median PSA nadir of 0.3 ng/ml at a median time to nadir of 30 months. In our cohort, 36.2% experienced a benign PSA bounce. Absence of PSA bounce, initial PSA, and testosterone at the time of nadir proved to be significant predictors of achieving a PSA nadir below threshold. PSA kinetics after prostate SBRT were well described with a functional volume model with fitted half-lives of 4.4 and 14.8 months for malignant and benign sources of PSA, respectively. Patients treated with prostate SBRT experience an initial period of rapid PSA decline followed by a slow decline which will likely result in lower PSA nadirs after longer follow-up. The long-term disease specific impacts of these results remain to be determined. [ABSTRACT FROM AUTHOR]

Background Proctitis after radiation therapy for prostate cancer remains an ongoing clinical challenge and critical quality of life issue. SBRT could minimize rectal toxicity by reducing the volume of rectum receiving high radiation doses and offers the potential radiobiologic benefits of hypofractionation. This study sought to evaluate the incidence and severity of proctitis following SBRT for prostate cancer. Methods Between February 2008 and July 2011, 269 men with clinically localized prostate cancer were treated definitively with SBRT monotherapy at Georgetown University Hospital. All patients were treated to 35-36.25Gy in 5 fractions delivered with the CyberKnife Radiosurgical System (Accuray). Rectal bleeding was recorded and scored using the CTCAE v.4. Telangiectasias were graded using the Vienna Rectoscopy Score (VRS). Proctitis was assessed via the Bowel domain of the Expanded Prostate Index Composite (EPIC)-26 at baseline and at 1, 3, 6, 9, 12, 18 and 24 months post-SBRT. Results The median age was 69 years with a median prostate volume of 39 cc. The median follow-up was 3.9 years with a minimum follow-up of two years. The 2-year actuarial incidence of late rectal bleeding ≥ grade 2 was 1.5%. Endoscopy revealed VRS Grade 2 rectal telangiectasias in 11% of patients. All proctitis symptoms increased at one month post-SBRT but returned to near-baseline with longer follow-up. The most bothersome symptoms were bowel urgency and frequency. At one month post-SBRT, 11.2% and 8.5% of patients reported a moderate to big problem with bowel urgency and frequency, respectively. The EPIC bowel summary scores declined transiently at 1 month and experienced a second, more protracted decline between 6 months and 18 months before returning to near-baseline at two years post-SBRT. Prior to treatment, 4.1% of men felt their bowel function was a moderate to big problem which increased to 11.5% one month post-SBRT but returned to near-baseline at two years post-SBRT. Conclusions In this single institution cohort, the rate and severity of proctitis observed following SBRT is low. QOL decreased on follow-up; however, our results compare favorably to those reported for patients treated with alternative radiation modalities. Future prospective randomized studies are needed to confirm these observations. [ABSTRACT FROM AUTHOR]

Highlights: [•] MnO x –CeO2–ZrO2/γ-Al2O3 catalyst showed high SCR activity at low temperature. [•] MnO x –CeO2–ZrO2/γ-Al2O3 catalyst was well-behaved in the presence of SO2 and H2O. [•] NO and NH3 could be adsorbed on the catalyst in different forms. [•] The SCR reaction route followed both of the E–R mechanism and L–H mechanism. [Copyright &y& Elsevier]

Background: Treating prostate cancer with SBRT could potentially minimize radiation proctitis by reducing high-dose rectal irradiation. In addition, it offers the potential radiobiologic benefits of hypofractionation. This study reports the endoscopic changes and the associated clinical rectal toxicity in these patients. Methods: We reviewed the records of patients treated from 2008-2011 for localized prostate cancer who had rectal endoscopy following SBRT. SBRT was delivered either as primary treatment in 5 fractions of 7-7.25 Gy, or as an initial boost in 3 fractions of 6.5 Gy followed by conventionally fractionated radiotherapy to 45-50.4 Gy. Endoscopic changes were graded using the Vienna Rectoscopy Score (VRS). Rectal toxicity was graded via CTCAEv.4. Rectal quality of life (QOL) was assessed via the bowel domain of the EPIC-26 questionnaire. Results: Fifty-one patients with a median 23 months follow-up were analyzed. Thirty-five patients completed SBRT monotherapy and 16 patients received SBRT as a boost to conventionally fractionated IMRT. The median interval from SBRT to rectal endoscopy was 13 months. Endoscopy revealed VRS Grade 1-2 telangiectasias for 10 patients and VRS Grade 1-2 mucosal edema for 12 patients. No rectal ulcerations, strictures or necrosis were observed. Grade 1-2 late rectal bleeding occurred in 10 patients. There were no CTCAEv.4 Grade ⩾3 toxicities. Mean EPIC bowel scores decreased from a baseline value of 96.9 to 82.3 at 1-month, but subsequently increased to 91.0 at 24 months. Conclusions: In this cohort that is skewed towards patients with rectal complaints, the rate and severity of endoscopic changes following SBRT is low. Rectal toxicity and QOL were comparable to patients treated with other radiation modalities. Prospective trials examining the endoscopic outcomes following SBRT for prostate cancer are needed for confirmation of the findings of this study. Trial registration: The Georgetown Institutional Review Board has approved this retrospective study (IRB 2009-510). [ABSTRACT FROM AUTHOR]

Highlights: [•] It is the first time of using CuO–MnO2–Fe2O3/γ-Al2O3 catalysts on Hg0 oxidation. [•] This study showed a potential for SCR and Hg0 oxidation in a single-step process. [•] We investigated the impacts of acid gases on Hg0 oxidation. [•] Increasing information on Hg0 oxidation mechanism over SCR catalysts was achieved. [Copyright &y& Elsevier]

Background: Hypofractionated stereotactic body radiation therapy (SBRT) has been advanced as monotherapy for low-risk prostate cancer. We examined the dose distributions and early clinical outcomes using this modality for the treatment of intermediate-risk prostate cancer. Methods: Forty-one sequential hormone-naïve intermediate-risk prostate cancer patients received 35-36.25 Gy of CyberKnife-delivered SBRT in 5 fractions. Radiation dose distributions were analyzed for coverage of potential microscopic ECE by measuring the distance from the prostatic capsule to the 33 Gy isodose line. PSA levels, toxicities, and quality of life (QOL) measures were assessed at baseline and follow-up. Results: All patients completed treatment with a mean coverage by the 33 Gy isodose line extending >5 mm beyond the prostatic capsule in all directions except posteriorly. Clinical responses were documented by a mean PSA decrease from 7.67 ng/mL pretreatment to 0.64 ng/mL at the median follow-up of 21 months. Forty patients remain free from biochemical progression. No Grade 3 or 4 toxicities were observed. Mean EPIC urinary irritation/ obstruction and bowel QOL scores exhibited a transient decline post-treatment with a subsequent return to baseline. No significant change in sexual QOL was observed. Conclusions: In this intermediate-risk patient population, an adequate radiation dose was delivered to areas of expected microscopic ECE in the majority of patients. Although prospective studies are needed to confirm long-term tumor control and toxicity, the short-term PSA response, biochemical relapse-free survival rate, and QOL in this interim analysis are comparable to results reported for prostate brachytherapy or external beam radiotherapy. [ABSTRACT FROM AUTHOR]

Abstract: Currently, selective catalytic reduction (SCR) of NO x with NH3 has been widely applied to reduce the emission of nitrogen oxides from mobile and stationary sources. But the detailed SCR reaction mechanism is still controversial and lacks the related comparative study of molecule modeling. The SCR reaction belongs to the gas–solid multiphase reaction, in which the adsorption of NH3 and NO by the catalysts plays an important role. In the present study, the adsorption properties of NH3 and NO on both the dry and partially hydroxylated γ-Al2O3 (110) surfaces supported CuO were revealed using the density-function theory (DFT) calculations. The results showed that NH3 could be adsorbed strongly on the dry (110) surface in the form of coordinated NH3 and NH4 +. Some of the coordinated NH3 could then undergo H-abstraction and form the –NH2 species. NO could be adsorbed weakly on the dry surface, and could also be adsorbed as bidentate nitrates or bridged nitrites. However, the adsorption activation of NH3 and NO on the partially hydroxylated surface was much weaker. The results of the DFT calculations are in good agreement with the experimental results and provided detailed clues to understand the adsorption mechanism of NH3 and NO on the CuO/γ-Al2O3 catalysts. [Copyright &y& Elsevier]

Background: Stereotactic body radiation therapy (SBRT) delivers high doses of radiation to the prostate while minimizing radiation to adjacent normal tissues. Large fraction sizes may increase the risk of functional decrements. Treatment-related bother may be more important to a patient than treatment-related dysfunction. This study reports on patient-reported outcomes following SBRT for clinically localized prostate cancer.Methods: Between August 2007 and July 2011, 228 consecutive hormone-naïve patients with clinically localized prostate cancer were treated with 35-36.25 Gy SBRT delivered using the CyberKnife Radiosurgical System (Accuray) in 5 fractions. Quality of life was assessed using the American Urological Association Symptom Score (AUA) and the Expanded Prostate Cancer Index Composite (EPIC)-26. Urinary symptom flare was defined as an AUA score 15 or more with an increase of 5 or more points above baseline 6 months after treatment.Results: 228 patients (88 low-, 126 intermediate- and 14 high-risk) at a median age of 69 (44-90) years received SBRT with a minimum follow-up of 24 months. EPIC urinary and bowel summary scores declined transiently at 1 month and experienced a second, more protracted decline between 9 months and 18 months before returning to near baseline 2 years post-SBRT. 14.5% of patients experienced late urinary symptom flare following treatment. Patients who experienced urinary symptom flare had poorer bowel quality of life following SBRT. EPIC scores for urinary bother declined transiently, first at 1 month and again at 12 months, before approaching pre-treatment scores by 2 years. Bowel bother showed a similar pattern, but the second decline was smaller and lasted 9 months to 18 months. EPIC sexual summary and bother scores progressively declined over the 2 years following SBRT without recovery.Conclusions: In the first 2 years, the impact of SBRT on urination and defecation was minimal. Transient late increases in urinary and bowel dysfunction and bother were observed. However, urinary and bowel function and bother recovered to near baseline by 2 years post-SBRT. Sexual dysfunction and bother steadily increased following treatment without recovery. SBRT for clinically localized prostate cancer was well tolerated with treatment-related dysfunction and bother comparable to conventionally fractionated radiation therapy or brachytherapy. [ABSTRACT FROM AUTHOR]

Background: Obstructive voiding symptoms (OVS) are common following prostate cancer treatment with radiation therapy. The risk of urinary retention (UR) following hypofractionated radiotherapy has yet to be fully elucidated. This study sought to evaluate OVS and UR requiring catheterization following SBRT for prostate cancer.Methods: Patients treated with SBRT for localized prostate cancer from February 2008 to July 2011 at Georgetown University were included in this study. Treatment was delivered using the CyberKnife® with doses of 35 Gy-36.25 Gy in 5 fractions. UR was prospectively scored using the CTCAE v.3. Patient-reported OVS were assessed using the IPSS-obstructive subdomain at baseline and at 1, 3, 6, 9, 12, 18 and 24 months. Associated bother was evaluated via the EPIC-26.Results: 269 patients at a median age of 69 years received SBRT with a median follow-up of 3 years. The mean prostate volume was 39 cc. Prior to treatment, 50.6% of patients reported moderate to severe lower urinary track symptoms per the IPSS and 6.7% felt that weak urine stream and/or incomplete emptying were a moderate to big problem. The 2-year actuarial incidence rates of acute and late UR ≥ grade 2 were 39.5% and 41.4%. Alpha-antagonist utilization rose at one month (58%) and 18 months (48%) post-treatment. However, Grade 3 UR was low with only 4 men (1.5%) requiring catheterization and/or TURP. A mean baseline IPSS-obstructive score of 3.6 significantly increased to 5.0 at 1 month (p < 0.0001); however, it returned to baseline in 92.6% within a median time of 3 months. Late increases in OVS were common, but transient. Only 7.1% of patients felt that weak urine stream and/or incomplete emptying was a moderate to big problem at two years post-SBRT (p = 0.6854).Conclusions: SBRT treatment caused an acute increase in OVS which peaked within the first month post-treatment, though acute UR requiring catheterization was rare. OVS returned to baseline in > 90% of patients within a median time of three months. Transient Late increases in OVS were common. However, less than 10% of patients felt that OVS were a moderate to big problem at two years post-SBRT. [ABSTRACT FROM AUTHOR]

Purpose: Urinary incontinence (UI) following prostate radiotherapy is a rare toxicity that adversely affects a patient's quality of life. This study sought to evaluate the incidence of UI following stereotactic body radiation therapy (SBRT) for prostate cancer.Methods: Between February, 2008 and October, 2010, 204 men with clinically localized prostate cancer were treated definitively with SBRT at Georgetown University Hospital. Patients were treated to 35-36.25 Gray (Gy) in 5 fractions delivered with the CyberKnife (Accuray). UI was assessed via the Expanded Prostate Index Composite (EPIC)-26.Results: Baseline UI was common with 4.4%, 1.0% and 3.4% of patients reporting leaking > 1 time per day, frequent dribbling and pad usage, respectively. Three year post treatment, 5.7%, 6.4% and 10.8% of patients reported UI based on leaking > 1 time per day, frequent dribbling and pad usage, respectively. Average EPIC UI summary scores showed an acute transient decline at one month post-SBRT then a second a gradual decline over the next three years. The proportion of men feeling that their UI was a moderate to big problem increased from 1% at baseline to 6.4% at three years post-SBRT.Conclusions: Prostate SBRT was well tolerated with UI rates comparable to conventionally fractionated radiotherapy and brachytherapy. More than 90% of men who were pad-free prior to treatment remained pad-free three years following treatment. Less than 10% of men felt post-treatment UI was a moderate to big problem at any time point following treatment. Longer term follow-up is needed to confirm late effects. [ABSTRACT FROM AUTHOR]

Background: Hypofractionated stereotactic body radiation therapy (SBRT) has been advanced as monotherapy for low-risk prostate cancer. We examined the dose distributions and early clinical outcomes using this modality for the treatment of intermediate-risk prostate cancer.Methods: Forty-one sequential hormone-naïve intermediate-risk prostate cancer patients received 35-36.25 Gy of CyberKnife-delivered SBRT in 5 fractions. Radiation dose distributions were analyzed for coverage of potential microscopic ECE by measuring the distance from the prostatic capsule to the 33 Gy isodose line. PSA levels, toxicities, and quality of life (QOL) measures were assessed at baseline and follow-up.Results: All patients completed treatment with a mean coverage by the 33 Gy isodose line extending >5 mm beyond the prostatic capsule in all directions except posteriorly. Clinical responses were documented by a mean PSA decrease from 7.67 ng/mL pretreatment to 0.64 ng/mL at the median follow-up of 21 months. Forty patients remain free from biochemical progression. No Grade 3 or 4 toxicities were observed. Mean EPIC urinary irritation/obstruction and bowel QOL scores exhibited a transient decline post-treatment with a subsequent return to baseline. No significant change in sexual QOL was observed.Conclusions: In this intermediate-risk patient population, an adequate radiation dose was delivered to areas of expected microscopic ECE in the majority of patients. Although prospective studies are needed to confirm long-term tumor control and toxicity, the short-term PSA response, biochemical relapse-free survival rate, and QOL in this interim analysis are comparable to results reported for prostate brachytherapy or external beam radiotherapy.Trial Registration: The Georgetown Institutional Review Board has approved this retrospective study (IRB 2009-510). [ABSTRACT FROM AUTHOR]

Background: Concurrent chemoradiation is a standard option for locally advanced pancreatic cancer (LAPC). Concurrent conventional radiation with full-dose gemcitabine has significant toxicity. Stereotactic body radiation therapy (SBRT) may provide the opportunity to administer radiation in a shorter time frame with similar efficacy and reduced toxicity. This Pilot study assessed the safety of concurrent full-dose gemcitabine with SBRT for LAPC.Methods: Patients received gemcitabine, 1000 mg/m2 for 6 cycles. During week 4 of cycle 1, patients received SBRT (25 Gy delivered in five consecutive daily fractions of 5 Gy prescribed to the 75-83% isodose line). Acute and late toxicities were assessed using NIH CTCAE v3. Tumor response was assessed by RECIST. Patients underwent an esophagogastroduodenoscopy at baseline, 2, and 6 months to assess the duodenal mucosa. Quality of life (QoL) data was collected before and after treatment using the QLQ-C30 and QLQ-PAN26 questionnaires.Results: Between September 2009 and February 2011, 11 patients enrolled with one withdrawal during radiation therapy. Patients had grade 1 to 2 gastrointestinal toxicity from the start of SBRT to 2 weeks after treatment. There were no grade 3 or greater radiation-related toxicities or delays for cycle 2 of gemcitabine. On endoscopy, there were no grade 2 or higher mucosal toxicities. Two patients had a partial response. The median progression free and overall survival were 6.8 and 12.2 months, respectively. Global QoL did not change between baseline and immediately after radiation treatment.Conclusions: SBRT with concurrent full dose gemcitabine is safe when administered to patients with LAPC. There is no delay in administration of radiation or chemotherapy, and radiation is completed with minimal toxicity. [ABSTRACT FROM AUTHOR]

Background: Stereotactic body radiation therapy (SBRT) delivers fewer high-dose fractions of radiation which may be radiobiologically favorable to conventional low-dose fractions commonly used for prostate cancer radiotherapy. We report our early experience using SBRT for localized prostate cancer.Methods: Patients treated with SBRT from June 2008 to May 2010 at Georgetown University Hospital for localized prostate carcinoma, with or without the use of androgen deprivation therapy (ADT), were included in this retrospective review of data that was prospectively collected in an institutional database. Treatment was delivered using the CyberKnife® with doses of 35 Gy or 36.25 Gy in 5 fractions. Biochemical control was assessed using the Phoenix definition. Toxicities were recorded and scored using the CTCAE v.3. Quality of life was assessed before and after treatment using the Short Form-12 Health Survey (SF-12), the American Urological Association Symptom Score (AUA) and Sexual Health Inventory for Men (SHIM) questionnaires. Late urinary symptom flare was defined as an AUA score ≥ 15 with an increase of  ≥ 5 points above baseline six months after the completion of SBRT.Results: One hundred patients (37 low-, 55 intermediate- and 8 high-risk according to the D'Amico classification) at a median age of 69 years (range, 48-90 years) received SBRT, with 11 patients receiving ADT. The median pre-treatment prostate-specific antigen (PSA) was 6.2 ng/ml (range, 1.9-31.6 ng/ml) and the median follow-up was 2.3 years (range, 1.4-3.5 years). At 2 years, median PSA decreased to 0.49 ng/ml (range, 0.1-1.9 ng/ml). Benign PSA bounce occurred in 31% of patients. There was one biochemical failure in a high-risk patient, yielding a two-year actuarial biochemical relapse free survival of 99%. The 2-year actuarial incidence rates of GI and GU toxicity ≥ grade 2 were 1% and 31%, respectively. A median baseline AUA symptom score of 8 significantly increased to 11 at 1 month (p=0.001), however returned to baseline at 3 months (p=0.60). Twenty one percent of patients experienced a late transient urinary symptom flare in the first two years following treatment. Of patients who were sexually potent prior to treatment, 79% maintained potency at 2 years post-treatment.Conclusions: SBRT for clinically localized prostate cancer was well tolerated, with an early biochemical response similar to other radiation therapy treatments. Benign PSA bounces were common. Late GI and GU toxicity rates were comparable to conventionally fractionated radiation therapy and brachytherapy. Late urinary symptom flares were observed but the majority resolved with conservative management. A high percentage of men who were potent prior to treatment remained potent two years following treatment. [ABSTRACT FROM AUTHOR]

Background: Erectile dysfunction after prostate radiation therapy remains an ongoing challenge and critical quality of life issue. Given the higher dose of radiation per fraction using stereotactic body radiation therapy (SBRT) there is concern that post-SBRT impotency would be higher than conventional radiation therapy approaches. This study sought to evaluate potency preservation and sexual function following SBRT for prostate cancer.Methods: Between February 2008 and March 2011, 216 men with clinically localized prostate cancer were treated definitively with SBRT monotherapy at Georgetown University Hospital. Potency was defined as the ability to have an erection firm enough for intercourse with or without sexual aids while sexual activity was defined as the ability to have an erection firm enough for masturbation and foreplay. Patients who received androgen deprivation therapy (ADT) were excluded from this study. Ninety-seven hormone-naïve men were identified as being potent at the initiation of therapy and were included in this review. All patients were treated to 35-36.25 Gy in 5 fractions delivered with the CyberKnife Radiosurgical System (Accuray). Prostate specific antigen (PSA) and total testosterone levels were obtained pre-treatment, every 3 months for the first year and every 6 months for the subsequent year. Sexual function was assessed with the Sexual Health Inventory for Men (SHIM), the Expanded Prostate Index Composite (EPIC)-26 and Utilization of Sexual Medication/Device questionnaires at baseline and all follow-up visits.Results: Ninety-seven men (43 low-, 50 intermediate- and 4 high-risk) at a median age of 68 years (range, 48-82 years) received SBRT. The median pre-treatment PSA was 5.9 ng/ml and the minimum follow-up was 24 months. The median pre-treatment total serum testosterone level was 11.4 nmol/L (range, 4.4-27.9 nmol/L). The median baseline SHIM was 22 and 36% of patients utilized sexual aids prior to treatment. Although potency rates declined following treatment: 100% (baseline); 68% (6 months); 62% (12 months); 57% (18 months) and 54.4% (24 months), 78% of previously potent patients had erections sufficient for sexual activity at 24 months post-treatment. Overall sexual aid utilization increased from 36% at baseline to 49% at 24 months. Average EPIC sexual scores showed a slow decline over the first two years following treatment: 77.6 (baseline); 68.7 (6 months); 63.2 (12 months); 61.9 (18 months); 59.3 (24 months). All sexual functions including orgasm declined with time. Prior to treatment, 13.4% of men felt their sexual function was a moderate to big problem which increased to 26.7% two years post treatment. Post-treatment testosterone levels gradually decreased with a median value at two year follow-up of 10.7 nmol/L. However, the average EPIC hormonal scores did not illustrate a statistically significant difference two years post-treatment. Review of the radiation doses to the penile bulb in this study, a potential marker of post-treatment sexual function, revealed that the dose was relatively low and at these low doses the percentage of the penile bulb receiving 29.5 Gy did not correlate with the development of ED.Conclusions: Men undergoing SBRT monotherapy for prostate cancer report sexual outcomes comparable to those reported for conventional radiation modalities within the first 24 months after treatment. Longer follow-up is required to confirm the durability of these findings. [ABSTRACT FROM AUTHOR]

Background: Treating prostate cancer with SBRT could potentially minimize radiation proctitis by reducing high-dose rectal irradiation. In addition, it offers the potential radiobiologic benefits of hypofractionation. This study reports the endoscopic changes and the associated clinical rectal toxicity in these patients.Methods: We reviewed the records of patients treated from 2008-2011 for localized prostate cancer who had rectal endoscopy following SBRT. SBRT was delivered either as primary treatment in 5 fractions of 7-7.25 Gy, or as an initial boost in 3 fractions of 6.5 Gy followed by conventionally fractionated radiotherapy to 45-50.4 Gy. Endoscopic changes were graded using the Vienna Rectoscopy Score (VRS). Rectal toxicity was graded via CTCAEv.4. Rectal quality of life (QOL) was assessed via the bowel domain of the EPIC-26 questionnaire.Results: Fifty-one patients with a median 23 months follow-up were analyzed. Thirty-five patients completed SBRT monotherapy and 16 patients received SBRT as a boost to conventionally fractionated IMRT. The median interval from SBRT to rectal endoscopy was 13 months. Endoscopy revealed VRS Grade 1-2 telangiectasias for 10 patients and VRS Grade 1-2 mucosal edema for 12 patients. No rectal ulcerations, strictures or necrosis were observed. Grade 1-2 late rectal bleeding occurred in 10 patients. There were no CTCAEv.4 Grade ≥3 toxicities. Mean EPIC bowel scores decreased from a baseline value of 96.9 to 82.3 at 1-month, but subsequently increased to 91.0 at 24 months.Conclusions: In this cohort that is skewed towards patients with rectal complaints, the rate and severity of endoscopic changes following SBRT is low. Rectal toxicity and QOL were comparable to patients treated with other radiation modalities. Prospective trials examining the endoscopic outcomes following SBRT for prostate cancer are needed for confirmation of the findings of this study.Trial Registration: The Georgetown Institutional Review Board has approved this retrospective study (IRB 2009-510). [ABSTRACT FROM AUTHOR]