3,433 research outputs found
Diverter Decision Aiding for In-Flight Diversions
It was determined that artificial intelligence technology can provide pilots with the help they need in making the complex decisions concerning en route changes in a flight plan. A diverter system should have the capability to take all of the available information and produce a recommendation to the pilot. Phase three illustrated that using Joshua to develop rules for an expert system and a Statice database provided additional flexibility by permitting the development of dynamic weighting of diversion relevant parameters. This increases the fidelity of the AI functions cited as useful in aiding the pilot to perform situational assessment, navigation rerouting, flight planning/replanning, and maneuver execution. Additionally, a prototype pilot-vehicle interface (PVI) was designed providing for the integration of both text and graphical based information. Advanced technologies were applied to PVI design, resulting in a hierarchical menu based architecture to increase the efficiency of information transfer while reducing expected workload. Additional efficiency was gained by integrating spatial and text displays into an integrated user interface
Diverter AI based decision aid, phases 1 and 2
It was determined that a system to incorporate artificial intelligence (AI) into airborne flight management computers is feasible. The AI functions that would be most useful to the pilot are to perform situational assessment, evaluate outside influences on the contemplated rerouting, perform flight planning/replanning, and perform maneuver planning. A study of the software architecture and software tools capable of demonstrating Diverter was also made. A skeletal planner known as the Knowledge Acquisition Development Tool (KADET), which is a combination script-based and rule-based system, was used to implement the system. A prototype system was developed which demonstrates advanced in-flight planning/replanning capabilities
A Phase I/II Trial of Fairly Brief Androgen Suppression and Stereotactic Radiation Therapy for High-Risk Prostate Cancer (FASTR-2): Preliminary Results and Toxicity Analysis
Purpose: FASTR was designed to provide a compact treatment course for high-risk prostate cancer patients but was discontinued because of excess toxicity. We present the results of FASTR-2, which used a lower dose to the prostate (35 Gy vs 40 Gy), smaller posterior PTV margin (4 mm vs 5 mm) and omitted nodal radiation to lower the volumes of rectum receiving high and intermediate doses compared with FASTR. Gastrointestinal (GI) and genitourinary (GU) toxicities at baseline, 6 weeks, 6 months, and 1 year and biochemical control rates are presented. Methods and Materials: Eligibility included high-risk prostate cancer (cT3/4, prostate-specific antigen \u3e20 or Gleason Score ≥8), age ≥70 or refused standard treatment, and no evidence of metastatic disease. Patients received 18 months of androgen deprivation therapy starting 2 months before radiation. Clinical target volume was defined as prostate plus proximal 1-cm seminal vesicles. PTV was a nonuniform expansion around clinical target volume (4 mm posteriorly, 5 mm in all other directions). Volumetric arc therapy was used for treatment delivery (35 Gy delivered in 5 weekly fractions of 7 Gy each), and cone beam computed tomography with soft tissue matching (no fiducial placement) was used for daily image guidance. Toxicity was assessed at 6 weeks, 6 months, and 1 year according to Common Toxicity Criteria. Results: In the study, 30 patients were enrolled in FASTR-2 between 2015 and 2017. Two patients were withdrawn owing to ineligibility after enrollment. One patient (3.7%) reported grade 2 GI toxicity at 6 weeks. There was no reported grade ≥2 GI toxicity at 6 months or 1 year. There were no reported episodes of rectal bleeding. Four patients (14.8%), 5 patients (17.9%), and 5 patients (21.7%) reported grade 2 GU toxicity at 6 weeks, 6 months, and 1 year, respectively. There were no reported cases of grade ≥3 GU toxicity. The most common toxicities were nocturia and urinary frequency or urgency. Conclusions: FASTR-2 was more tolerable than FASTR, with no grade ≥3 toxicities reported, in keeping with expectations based on our previous FASTR analysis. Long-term follow-up is necessary to ensure disease control and toxicity outcomes are comparable to conventional high-risk treatment paradigms
Technology assessment of automated atlas based segmentation in prostate bed contouring
<p>Abstract</p> <p>Background</p> <p>Prostate bed (PB) contouring is time consuming and associated with inter-observer variability. We evaluated an automated atlas-based segmentation (AABS) engine in its potential to reduce contouring time and inter-observer variability.</p> <p>Methods</p> <p>An atlas builder (AB) manually contoured the prostate bed, rectum, left femoral head (LFH), right femoral head (RFH), bladder, and penile bulb of 75 post-prostatectomy cases to create an atlas according to the recent RTOG guidelines. 5 other Radiation Oncologists (RO) and the AABS contoured 5 new cases. A STAPLE contour for each of the 5 patients was generated. All contours were anonymized and sent back to the 5 RO to be edited as clinically necessary. All contouring times were recorded. The dice similarity coefficient (DSC) was used to evaluate the unedited- and edited- AABS and inter-observer variability among the RO. Descriptive statistics, paired t-tests and a Pearson correlation were performed. ANOVA analysis using logit transformations of DSC values was calculated to assess inter-observer variability.</p> <p>Results</p> <p>The mean time for manual contours and AABS was 17.5- and 14.1 minutes respectively (p = 0.003). The DSC results (mean, SD) for the comparison of the unedited-AABS versus STAPLE contours for the PB (0.48, 0.17), bladder (0.67, 0.19), LFH (0.92, 0.01), RFH (0.92, 0.01), penile bulb (0.33, 0.25) and rectum (0.59, 0.11). The DSC results (mean, SD) for the comparison of the edited-AABS versus STAPLE contours for the PB (0.67, 0.19), bladder (0.88, 0.13), LFH (0.93, 0.01), RFH (0.92, 0.01), penile bulb (0.54, 0.21) and rectum (0.78, 0.12). The DSC results (mean, SD) for the comparison of the edited-AABS versus the expert panel for the PB (0.47, 0.16), bladder (0.67, 0.18), LFH (0.83, 0.18), RFH (0.83, 0.17), penile bulb (0.31, 0.23) and rectum (0.58, 0.09). The DSC results (mean, SD) for the comparison of the STAPLE contours and the 5 RO are PB (0.78, 0.15), bladder (0.96, 0.02), left femoral head (0.87, 0.19), right femoral head (0.87, 0.19), penile bulb (0.70, 0.17) and the rectum (0.89, 0.06). The ANOVA analysis suggests inter-observer variability among at least one of the 5 RO (p value = 0.002).</p> <p>Conclusion</p> <p>The AABS tool results in a time savings, and when used to generate auto-contours for the femoral heads, bladder and rectum had superior to good spatial overlap. However, the generated auto-contours for the prostate bed and penile bulb need improvement.</p
Oral anticoagulant treatment in rheumatoid arthritis patients with atrial fibrillation results of an international audit
Objective: To describe the prevalence of atrial fibrillation (AF) in patients with rheumatoid arthritis (RA), and to evaluate the proportion of patients with AF receiving guideline-recommended anticoagulation for prevention of stroke, based on data from a large international audit. Methods: The cohort was derived from the international audit SUrvey of cardiovascular disease Risk Factors in patients with Rheumatoid Arthritis (SURF-RA) which collected data from 17 countries during 2014-2019. We evaluated the prevalence of AF across world regions and explored factors associated with the presence of AF with multivariable logistic regression models. The proportion of AF patients at high risk of stroke (CHA(2)DS(2)-VASc & GE; 2 in males and & GE; 3 in females) receiving anticoagulation was examined. Results: Of the total SURF-RA cohort (n = 14,503), we included RA cases with data on whether the diagnosis of AF was present or not (n = 7,665, 75.1% women, mean (SD) age 58.7 (14.1) years). A total of 288 (3.8%) patients had a history of AF (4.4% in North America, 3.4% in Western Europe, 2.8% in Central and Eastern Europe and 1.5% in Asia). Factors associated with the presence of AF were older age, male sex, atherosclerotic cardiovascular disease, heart failure and hypertension. Two-hundred and fifty-five (88.5%) RA patients had a CHA(2)DS(2)-VASc score indicating recommendation for oral anticoagulant treatment, and of them, 164 (64.3%) were anticoagulated. Conclusion: Guideline-recommended anticoagulant therapy for prevention of stroke due to AF may not be optimally implemented among RA patients, and requires special attention.Peer reviewe
Supplementary data: Chemoradiotherapy in octogenarians as primary treatment for muscle-invasive bladder cancer
Chemoradiotherapy in octogenarians as primary treatment for muscle-invasive bladder cancer
Introduction: While radical cystectomy is the gold standard for muscle-invasive bladder cancer (MIBC), in octogenarians cystectomy results in a higher perioperative mortality rate (6.8‒11.1%) than in younger patients (2.2%). Trimodality therapy is a bladder-sparing regimen composed of transurethral resection of bladder tumour (TURBT) and chemoradiotherapy, with intent for salvage cystectomy, and has a 62.5‒90% initial complete response rate. In this study, we evaluate TURBT and chemoradiotherapy without salvage cystectomy in medically inoperable octogenarian patients. Methods: We identified a retrospective cohort of patients aged 80‒89 years with invasive urothelial carcinoma who received combination chemoradiotherapy between 2008 and June 2014. Outcomes were evaluated by Kaplan-Meier (KM) and Cox regression. Results: In 40 patients, the mean age was 84.5 years (interquartile range [IQR] 83‒86). Seventeen patients received hypofractionated, low-dose radiotherapy (LD) (37.5‒40 Gy), while 23 received conventionally fractionated radiotherapy (high-dose [HD]) (50‒65 Gy). Mean overall survival (OS) was 20.7 months (IQR 12.75‒23.25), while mean recurrence-free survival (RFS) was 13.75 months (IQR 3.75‒16.5). Patients receiving HD radiotherapy showed improved OS and local RFS (LRFS) without significant differences in Grade 3‒4 toxicities. Univariate Cox regression identified hydronephrosis as a predictor of worse OS and local recurrence and HD radiotherapy as a predictor of improved OS and local recurrence rates. Multivariate Cox regression identified hydronephrosis to be a significant predictor of LRFS. Conclusions: Primary chemoradiotherapy for inoperable patients with MIBC resulted in a three-year OS of 54.9% (comparable to cystectomy) and three-year RFS of 42.3%. Superior outcomes were associated with more aggressive chemoradiotherapy treatment. The results of the local control subanalyses in this study are hypothesis-generating due to the limited patient numbers in the cohort
Human Spotted Fever Rickettsial Infections
Serum specimens from patients at 4 sites in Peru were tested for evidence of spotted fever group rickettsial infection. Results showed that 30 (18%) of 170 patients had spotted fever group rickettsial infections, which likely caused their illnesses. These findings document laboratory-confirmed spotted fever from diverse areas of Peru
Diabetes mellitus and cardiovascular risk management in patients with rheumatoid arthritis: an international audit
Aim: The objective was to examine the prevalence of atherosclerotic cardiovascular disease (ASCVD) and its risk factors among patients with RA with diabetes mellitus (RA-DM) and patients with RA without diabetes mellitus (RAwoDM), and to evaluate lipid and blood pressure (BP) goal attainment in RA-DM and RAwoDM in primary and secondary prevention.
Methods: The cohort was derived from the Survey of Cardiovascular Disease Risk Factors in Patients with Rheumatoid Arthritis from 53 centres/19 countries/3 continents during 2014-2019. We evaluated the prevalence of cardiovascular disease (CVD) among RA-DM and RAwoDM. The study population was divided into those with and without ASCVD, and within these groups we compared risk factors and CVD preventive treatment between RA-DM and RAwoDM.
Results: The study population comprised of 10 543 patients with RA, of whom 1381 (13%) had DM. ASCVD was present in 26.7% in RA-DM compared with 11.6% RAwoDM (p<0.001). The proportion of patients with a diagnosis of hypertension, hyperlipidaemia and use of lipid-lowering or antihypertensive agents was higher among RA-DM than RAwoDM (p<0.001 for all). The majority of patients with ASCVD did not reach the lipid goal of low-density lipoprotein cholesterol <1.8 mmol/L. The lipid goal attainment was statistically and clinically significantly higher in RA-DM compared with RAwoDM both for patients with and without ASCVD. The systolic BP target of <140 mm Hg was reached by the majority of patients, and there were no statistically nor clinically significant differences in attainment of BP targets between RA-DM and RAwoDM.
Conclusion: CVD preventive medication use and prevalence of ASCVD were higher in RA-DM than in RAwoDM, and lipid goals were also more frequently obtained in RA-DM. Lessons may be learnt from CVD prevention programmes in DM to clinically benefit patients with RA .The work was supported by grants from the South Eastern Regional Health Authorities of Norway (2013064 for AGS and 2016063 for SR) and FOREUM (the Foundation for Research in Rheumatology for AMK). Further support was through a collaborative agreement for independent research from Eli Lilly who had no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript
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