Exploring the structure of predecisional information search in risky choice

It is commonly assumed that there are qualitatively distinct cognitive strategies that underlie decision making. Because cognitive strategies differ in how information is processed, predecisional information search offers a window onto these strategies. Using a bottom-up approach, we examine whether predecisional information search actually reflects the use of distinct strategies. Specifically, we investigate the extent to which the heterogeneity in people's predecisional information search in a risky choice task reflects qualitatively distinct patterns that should emerge when people use distinct strategies. Our analysis takes into account the distribution of attention across attributes and transitions between attributes. Using cluster analysis, we find just two qualitatively different clusters with low separability: one characterized by balanced attention to all attributes and by transitions occurring mostly within the same option, and one characterized by a focus on outcome information and by frequent attribute-wise transitions. These two clusters were also associated with differences in people's choice behavior. The distribution of these clusters varied considerably across individuals, but less so across choice problems, suggesting that information search is not necessarily guided by features of the choice problem—this result challenges current theories on strategy selection. Our results challenge the common assumption that heterogeneity in predecisional information search is differentiated along clearly distinct information processing policies. Instead, the differentiation seems to fall into just two broad clusters—one resembling rational principles of expectation computation, the other reflecting heuristic principles that neglect probabilities—with considerable variability within each cluster

Positron annihilation study using 64CU positron source

This research is attributed to properties study of 64Cu isotope as a positron source. This isotope was obtained by neutron irradiation of copper foil in research nuclear reactor. The Doppler broadening spectrometer was used in this research to study the parameters of 64Cu. The experiment shows that, as 64Cu loses its activity, the peak to noise ratio increases, while the S parameter goes up and the W parameter goes down

Dose-escalated salvage radiotherapy after radical prostatectomy in high risk prostate cancer patients without hormone therapy: outcome, prognostic factors and late toxicity

Purpose: Evaluation of dose escalated salvage radiotherapy (SRT) in patients after radical prostatectomy (RP) who had never received antihormonal therapy. To investigate prognostic factors of the outcome of SRT and to analyze which patient subsets benefit most from dose escalation. Materials and methods: Between 2002 and 2008, 76 patients were treated in three different dose-groups: an earlier cohort treated with 66 Gy irrespective of pre-RT-characteristics and two later cohorts treated with 70 Gy or 75 Gy depending on pre-RT-characteristics. Biochemical-relapse-free-survival (bRFS), clinical-relapse-free-survival (cRFS) and late toxicity were evaluated. Results: Four-year bRFS and cRFS were 62.5% and 85%. Gleason score <8, positive surgical resection margin (PSRM) and low PSA (<= 0.5 ng/ml) before SRT resulted in higher bRFS. Analysis of the whole group showed no clear dose-outcome relationship. Patients with PSRM, however, had improved bRFS when escalating >66 Gy. While >70 Gy did not improve the overall results, 4-year bRFS for patients with manifest local recurrence in the high-dose group was still comparable to those without manifest local recurrences. No grade 4 and minimal grade 3 gastrointestinal and urinary toxicity were observed. Conclusions: Dose-escalated SRT achieves high biochemical control. The data strongly support the application of at least 70 Gy rather than 66 Gy. They do not prove positive effects of doses >70 Gy but do not disprove them as these doses were only applied to an unfavorable patients selection

Implications of TERT promoter mutations and telomerase activity for urothelial carcinogenesis

Telomerase activity imparts eukaryotic cells with unlimited proliferation capacity, one of the cancer hallmarks. Over 90% of human urothelial carcinoma of the bladder (UCB) are positive for telomerase activity. Telomerase activation can occur through several mechanisms. Mutations in the core promoter region of the human telomerase reverse transcriptase gene (TERT) cause telomerase reactivation in 60-80% of UCB, whereas the prevalence of these mutations is lower in urothelial cancers of other origins. TERT promoter mutations are the most frequent genetic alteration across all stages of UCB, indicating a strong selection pressure during neoplastic transformation.[Au:We avoid formulations referring to the article authors (“we”) in the abstract. I have edited the following text accordingly, OK?] TERT [Au:”promoter”?] promoter mutations could arise during regeneration of normal urothelium[Au:I tried to simplify here; is this what you meant?] and due to consequential telomerase reactivation, might be the basis of UCB initiation, which represents a new model for the origination of urothelial carcinogenesis. In the future, TERT promoter mutations and telomerase activity might have diagnostic and therapeutic applications in UCB

Deep learning-based classification of blue light cystoscopy imaging during transurethral resection of bladder tumors

Bladder cancer is one of the top 10 frequently occurring cancers and leads to most cancer deaths worldwide. Recently, blue light (BL) cystoscopy-based photodynamic diagnosis was introduced as a unique technology to enhance the detection of bladder cancer, particularly for the detection of flat and small lesions. Here, we aim to demonstrate a BL image-based artificial intelligence (AI) diagnostic platform using 216 BL images, that were acquired in four different urological departments and pathologically identified with respect to cancer malignancy, invasiveness, and grading. Thereafter, four pre-trained convolution neural networks were utilized to predict image malignancy, invasiveness, and grading. The results indicated that the classification sensitivity and specificity of malignant lesions are 95.77% and 87.84%, while the mean sensitivity and mean specificity of tumor invasiveness are 88% and 96.56%, respectively. This small multicenter clinical study clearly shows the potential of AI based classification of BL images allowing for better treatment decisions and potentially higher detection rates

Radical nephroureterectomy for pathologic T4 upper tract urothelial cancer: can oncologic outcomes be improved with multimodality therapy?

Purpose To report the outcomes of patients with pathologic T4 UTUC and investigate the potential impact of peri-operative chemotherapy combined with radical nephroureterectomy (RNU) and regional lymph node dissection (LND) on oncologic outcomes. Materials and Methods Patients with pathologic T4 UTUC were identified from the cohort of 1464 patients treated with RNU at 13 academic centers between 1987 and 2007. Oncologic outcomes were stratified according to utilization of perioperative systemic chemotherapy and regional LND as an adjunct to RNU. Results The study included 69 patients, 42 males (61%) with median age 73 (range 43-98). Median follow-up was 17 months (range: 6-88). Lymphovascular invasion was found in 47 (68%) and regional lymph node metastases were found in 31 (45%). Peri-operative chemotherapy was utilized in 29 (42%) patients. Patients treated with peri-operative chemotherapy and RNU with LND demonstrated superior oncologic outcomes compared to those not treated by chemotherapy and/or LND during RNU (3Y-DFS: 35% vs. 10%; P = 0.02 and 3Y-CSS: 28% vs. 14%; P = 0.08). In multivariate Cox regression analysis, administration of peri-operative chemotherapy and utilization of LND during RNU was associated with lower probability of recurrence (HR: 0.4, P = 0.01), and cancer specific mortality (HR: 0.5, P = 0.06). Conclusions Pathological T4 UTUC is associated with poor prognosis. Peri-operative chemotherapy combined with aggressive surgery, including lymph node dissection, may improve oncological outcomes. Our findings support the use of aggressive multimodal treatment in patients with advanced UTUC

The Impact of Previous Ureteroscopic Tumor Ablation on Oncologic Outcomes After Radical Nephrouretectomy for Upper Urinary Tract Urothelial Carcinoma

We investigated whether a history of endoscopic tumor ablation impacts oncologic outcomes after radical nephroureterectomy (RNU) for upper urinary tract urothelial carcinoma (UTUC). Using a multi-institutional database that contained patients who were treated with RNU, oncologic outcomes were assessed according to history of ureteroscopic tumor ablation. Disease-free survival (DFS) and cancer-specific survival (CSS) were estimated using the Kaplan-Meier survival analysis. Multivariate Cox regression analyses were performed to determine independent predictors of disease recurrence and cancer-specific mortality after RNU. The study included 1268 patients, 853 men and 415 women, with a mean age of 67.5 years (range 32-94 y) and 52.8 months median follow-up after RNU. A total of 175 (13%) patients underwent RNU after endoscopic tumor ablation and 1093 (87%) patients underwent RNU without a history of endoscopic ablation. The 5-year DFS and CSS rates were 72% and 77% in those with a history of tumor ablation vs 69% and 73% in those without a history of ablation (P = 0.171 and P = 0.365, respectively). In multivariate Cox regression analysis, history of ablation therapy was not associated with disease recurrence or cancer-specific mortality (hazard ratio [HR]: 0.79, P = 0.185 and HR: 0.7, P = 0.078, respectively). Our collaborative international efforts suggest that in selected patients, endoscopic tumor ablation does not adversely affect the recurrence and survival after subsequent RNU for UTUC. Our data support the continued role of ureteroscopic ablation of UTUC in appropriately selected patients.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90497/1/end-2E2010-2E0396.pd