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The value of proton therapy in managing prostate cancer is not yet defined. A recent study has reported promising long-term results for patients with localized prostate cancer who received proton therapy. However, results from ongoing clinical trials are required before determining the role of proton therapy for this indication.

Background/Objectives: Traditionally, proton therapy assumes a fixed relative biological effectiveness (RBE) value of 1.1, which can lead to inaccurate dose calculations in treatment planning. This study examines the effect of dynamic arc delivery and pencil beam scanning (PBS) linear energy transfer (LET) optimization on LET-dependent RBE dose escalation to nervous tissue structures in head and neck (H&N) cancer patients undergoing proton beam therapy, utilizing two RBE dose models. Methods: Fifteen head and neck cancer patients previously treated with PBS proton therapy at high risk of nervous tissue toxicity were retrospectively analyzed. Three plans were developed for each patient: PBS, dynamic arc, and PBS with LET optimization. RBE-weighted dose distributions were calculated and compared for all patient plans using a linear LET-weighted model and a tissue-specific α/β-dependent model. LET-dose (LETd) constraints were systematically tested to determine optimal values for plan quality and efficacy in altering LET spatial distribution in regions of concern. LET-dependent RBE enhancement was calculated for the three different planning methods. Results: Dynamic arc plans increased RBE enhancement when compared to PBS, while LET optimization for PBS consistently reduced RBE-enhanced dose to nervous tissue compared to non-optimized plans for both RBE models. Patient-specific variability in optimization benefit was observed, with the most significant improvements in cases with greater initial RBE enhancement. A maximum LETd constraint of 2.5 µm/keV above 80% of the maximum structure dose threshold was found to balance plan quality and RBE mitigation. Conclusions: Dynamic arc delivery increased RBE enhancement relative to static PBS. LET optimization successfully modified LETd spatial distributions to minimize RBE enhancement to nervous tissue structures when compared to non-LET optimized PBS and dynamic arc plans. Patient-specific risk stratification should be used when clinically deploying LET optimization.

Data comparing outcomes in prostate cancer and factors affecting treatment choice are sparse. To inform the design of a comparative effectiveness clinical trial, we engaged patients in developing a 28‐question survey about decision making on treatment and research participation and dispersed it among men greater than or equal to 50 years of age. The 1046 respondents ranked long‐term clinical outcomes as most important in making treatment decisions, specific functional outcomes as slightly less important, and duration, location, and cost of treatment as least important. Treatment choice was strongly impacted by side effect profile. Responses to whether the subject would agree to participation in a randomized trial between two types of radiation with minimal differences in outcomes were “yes” in 15%, “no” in 39%, and “undecided” in 46%. Responses to whether the subject would agree to participation in a randomized trial between two treatment durations with similar outcomes were yes in 36%, no in 24%, and undecided in 40%. Findings suggest many potential patients have strong treatment preferences and are averse to randomization, particularly when outcomes of importance may be affected. Patient engagement in study design and novel nonrandomized trial designs may offer a path to increase clinical trial success.

A relatively simple set of calculations was presented in 1994 to evaluate the effectiveness of each ASB cell as reactor, clarifier, and digester. The steady-state model, which incorporated estimates of solids settling and benthal feedback of BOD5 and nutrients, has been a reasonable diagnostic tool for municipal and industrial applications. Results have aided in understanding normal system function, the nature of chronic inefficiencies of individual systems, and appropriate modifications to meet changes in discharge requirements. For applications in the pulp and paper industry, several changes have been incorporated recently. Nitrogen limitation is not needed in modeling pulp and paper ASB reactions. Slowly biodegradable material is modeled as a contributor to soluble BOD5, and this contribution becomes a significant factor in the latter segments of an ASB. Phosphorus availability is modeled as a stoichiometric control of soluble BOD5 uptake. Anoxic microorganisms are assumed to be responsible for a portion of the soluble BOD5 consumption in the first ASB aeration zone. Finally, the long-term nutrient capture in ASBs is modeled as 3% for nitrogen and 28% for phosphorus.

In the current religious environment in the United States of America, religious disaffiliation has increased in every religion across the nation. This phenomenon has also affected the Church of Jesus Christ of Latter-day Saints. This case study will explore the religious aspects of the faith crises of individuals who have recently left the Church of Jesus Christ of Latter-day Saints. This qualitative case study will interview adult individuals in Utah. The research aims to find and research the similarities and themes in the individuals' stories.

Methods for preventing adolescent suicide are surveyed, and cognitive-behavioral therapy (CBT) is explored as a method for serving suicidal African American adolescents. Strengths, limitations, and compatibility of CBT with social work values are examined. Although CBT shows much promise in helping suicidal African American adolescents, research on the efficacy and effectiveness of CBT with this population is lacking. Suicide risk and protective factors and social inequities are evaluated as they relate to African American adolescents generally. In addition to relieving suicidal symptoms, CBT potentially could facilitate social liberation for this population.

Purpose: To investigate the feasibility of using cone-beam computed tomography (CBCT)-derived synthetic CTs to monitor the daily dose and trigger a plan review for adaptive proton therapy (APT) in head and neck cancer (HNC) patients. Methods: For 84 HNC patients treated with proton pencil-beam scanning (PBS), same-day CBCT and verification CT (vfCT) pairs were retrospectively collected. The ground truth CT (gtCT) was created by deforming the vfCT to the same-day CBCT, and it was then used as a dosimetric baseline and for establishing plan review trigger recommendations. Two different synthetic CT algorithms were tested; the corrected CBCT (corrCBCT) was created using an iterative image correction method and the virtual CT (virtCT) was created by deforming the planning CT to the CBCT, followed by a low-density masking process. Clinical treatment plans were recalculated on the image sets for evaluation. Results: Plan review trigger criteria for adaptive therapy were established after closely reviewing the cohort data. Compared to the vfCT, the corrCBCT and virtCT reliably produced dosimetric data more similar to the gtCT. The average discrepancy in D99 for high-risk clinical target volumes (CTV) was 1.1%, 0.7%, and 0.4% and for standard-risk CTVs was 1.8%, 0.5%, and 0.5% for the vfCT, corrCBCT, and virtCT, respectively. Conclusion: Streamlined APT has been achieved with the proposed plan review criteria and CBCT-based synthetic CT workflow.

Background The dose‐averaged linear energy transfer (LETD) in proton therapy (PT) has in pre‐clinical studies been linked to the relative biological effectiveness (RBE) of protons. Until recently, the most common PT delivery method in prostate cancer has been double‐scattered PT, with LETD only available through dedicated Monte Carlo (MC) simulations. However, as most studies of the relationship between LETD and RBE in double scattered PT have been focused on the head and neck region, existing MC implementations have not been capable of calculating LETD for the longer field ranges used, for example, in the pelvic region. Purpose The initial aim of this study was to implement a MC code allowing for LETD calculations in double‐scattered PT of prostate cancer. Additionally, we explored LETD profiles and LETD as a function of field configuration, by performing MC calculations for a large prostate cancer cohort treated with double‐scattered PT. Methods The components of a passive scattered clinical treatment nozzle used for delivery of extended field ranges, with two associated modulation wheels, were implemented into an existing FLUKA MC framework for LETD calculations. The code was validated to spread out Bragg peak (SOBP) measurements conducted using the treatment nozzle with 11 different range and modulation width configurations. After validation, LETD distributions were calculated on the planning computed tomographies of 582 prostate cancer patients treated with two‐field double‐scattered PT. All patients had symmetric field configurations with respect to the sagittal plane, with one pair of posterior oblique, lateral opposing, or anterior oblique fields. Dose and LETD volume parameters and the mean LETD ratio between the bladder and rectum were compared across the three groups. Results The range differences were below 1 mm for all SOBP scenarios used for calibration. For 9 of 11 SOBP scenarios, the modulation width differences were below 2 mm. For the patient simulations, the mean gamma pass rates (3 mm/3%) were at least 98% in the PTV, bladder, and rectum. Comparing anterior to posterior field configurations, the mean LETD in the bladder increased within both the 10 and 70 Gy iso‐dose regions, and conversely, the mean LETD decreased for the rectum. There was a marked difference in the mean bladder‐to‐rectum LETD ratios between anterior oblique, lateral opposing and posterior oblique field configurations. Conclusion A MC code allowing for accurate calculations of dose and LETD in double‐scattered PT of prostate cancer was implemented and validated. The LETD distributions in the rectum and bladder showed a systematic dependence on the field configuration.

Statins have shown promise as radiosensitizers in photon-based radiotherapy (RT), with studies demonstrating improved biochemical recurrence-free survival and reduced toxicity in prostate and other solid tumors. However, existing data derived entirely from photon-based RT and the potential synergy with proton therapy remain hypothetical at this stage. The current narrative review extrapolates the therapeutic benefits of statins observed in photon-based RT to proton therapy (PBT) to enhance therapeutic efficacy. The proposed combination of statins and PBT is a theoretical extension grounded in the mechanistic overlap between statin-induced radiosensitization and proton-specific advantages in dose conformity and linear energy transfer (LET). The hypothesis of enhanced synergy between statins and PBT warrants systematic preclinical testing and clinical trials before translation into standard practice.

The traditional black church has suffered in recent years from declining attendance. The biggest cause for the decline is linked to the massive exodus of younger generations from the traditional context. This phenomenon has inspired pastors, preachers, and thought leaders to engage in conversation about how to address the issue. That conversation has revealed generational engagement in preaching as one solution to stimulating congregational life within a traditional worship context. This thesis explores the use of a multigenerational preaching approach to inspire congregational engagement. This thesis will posit that preaching where sermons intentionally reach different generations in a similar context will result in engagement for both older and younger generations. The principles of this strategy will also prove useful beyond the current virtual settings imposed by the Coronavirus.