Geochemical Anomaly Detection in the Irankuh District Using Hybrid Machine Learning Technique and Fractal Modeling

Prediction of elemental concentrations is essential in mineral exploration as it plays a vital role in detailed exploration. New machine learning (ML) methods, such as hybrid models, are robust approaches infrequently used concerning other methods in this field; therefore, they have not been examined properly. In this study, a hybrid machine learning (HML) method was proposed based on combining K-Nearest Neighbor Regression (KNNR) and Random Forest Regression (RFR) to predict Pb and Zn grades in the Irankuh district, Sanandaj-Sirjan Zone.. The aim of the proposed study is to employ the hybrid model as a new method for grade distribution. The KNNR-RFR hybrid model results have been applied for the Pb and Zn anomalies classification. The hybrid (KNNR-RFR) method has shown more accurate prediction outputs based on the correlation coefficients than the single regression models with 0.66 and 0.54 correlation coefficients for Pb and Zn, respectively. The KNN-RF results were used to classify Pb and Zn anomalies in the study area. The concentration-area fractal model separated the main anomalous areas for these elements. The Pb and Zn main anomalies were correlated with mining activities and core drilling data. The current study demonstrates that the hybrid model has a substantial potential for the ore elemental distribution prediction. The presented model expresses a promising result and can predict ore grades in similar investigations

A novel phantom design for brachytherapy quality Assurance

Background: One major challenge in brachytherapy is to verify the accuracy of dose distributions calculated by the treatment planning system. In this project, a new phantom design has been introduced for quality assurance of dose distributions in gynocological (GYN) brachytherapy implants using EBT GafChromic film. Materials and Methods: This phantom has been designed and fabricated from 90 slabs of 18�16�0.2 cm3 Perspex to accommodate a tandem and ovoids assembly, which is normally used for GYN brachytherapy treatment. In addition, this phantom design is allowing the use EBT GafChromic films for dosimetric verification of GYN implants with Cs-137 Selectron LDR system. With this assembly, GafChromic films were exposed using a plan designed to deliver 2.5 Gy dose to point "A" in Manchester system for tandem and ovoids configurations and to deliver 1.5 Gy of dose to 0.5 cm distance from the lateral surface of ovoids for using ovoid-pair. The measured dose distributions with GafChromic films were compared with the TPS isodose lines both numerically and spatially. For a quantitative analysis of the results, the measured doses values at several points of interest were evaluated with the treatment planning data and values obtained following the TG-43 dose calculation formalism. Results: The results of these investigations have indicated that the new phantom design enables us to measure differences of greater than ±6 for LDR brachytherapy GYN treatments. Conclusion: The new phantom design could be utilized for the QA procedure of the brachytherapy remote after loading systems to confirm the accuracy of dose distribution in GYN implants

Salvage Brachytherapy for Biochemically Recurrent Prostate Cancer Following Primary Brachytherapy

Purpose. In this study, we evaluated our experience with salvage brachytherapy after discovery of biochemical recurrence after a prior brachytherapy procedure. Methods and Materials. From 2001 through 2012 twenty-one patients treated by brachytherapy within University of Kentucky or from outside centers developed biochemical failure and had no evidence of metastases. Computed tomography (CT) scans were evaluated; patients who had an underseeded portion of their prostate were considered for reimplantation. Results. The majority of the patients in this study (61.9%) were low risk and median presalvage PSA was 3.49 (range 17.41–1.68). Mean follow-up was 61 months. At last follow-up after reseeding, 11/21 (52.4%) were free of biochemical recurrence. There was a trend towards decreased freedom from biochemical recurrence in low risk patients (p = 0.12). International Prostate Symptom Scores (IPSS) increased at 3-month follow-up visits but decreased and were equivalent to baseline scores at 18 months. Conclusions. Salvage brachytherapy after primary brachytherapy is possible; however, in our experience the side-effect profile after the second brachytherapy procedure was higher than after the first brachytherapy procedure. In this cohort of patients we demonstrate that approximately 50% oncologic control, low risk patients appear to have better outcomes than others

Tracing human papillomavirus in skin and mucosal squamous cell carcinoma: a histopathological retrospective survey

Objective: The annual incidence of squamous cell carcinoma (SCC) has been increasing worldwide. The causative role of human papillomavirus (HPV) in SCC development of cutaneous has been controversial in the literature. In this study, we aimed to assess the presence of the histopathological features of HPV in SCC samples. Materials and Methods: This retrospective study was conducted at a tertiary referral skin center in 2020. Specimens of patients with a definite SCC diagnosis were evaluated for histopathological features of HPV, including koilocytosis, hyperkeratosis, acanthosis, hypergranulosis, parakeratosis, solar elastosis, papillomatosis, as well as the grade of the tumor. All the samples were re-evaluated by two dermatopathologists independently. Results: a total of 331 (male:female ratio= 3.9:1) cases of SCC were analyzed. The mean age was 68.1, with a 15.1 standard deviation. Most lesions were located on the face (40.5%), followed by the scalp (22.7%) and extremities (20.8%). Koilocytes were detected in 50 (15.1%) of lesions. The koilocytosis proportion was significantly higher in lesions on nails (38.1%, P-value= 0.007), oral cavity (36.8%, P-value= 0.014), and genitalia lesions (60.0%, P-value= 0.026). Although SCCs in-situ were found in 6.6% of our specimens, the highest koilocytosis proportion (64.7%) was detected in in-situ tumors, which was significantly more than other grades (P-value< 0.001). Conclusions: The histopathological features of HPV and in specific koilocytes can be frequently seen in SCC pathology. This association is more prominent in nail, oral, and genital lesions and is significantly higher in well-differentiated SCC

Dose distribution verification for GYN brachytherapy using EBT Gafchromic film and TG-43 calculation

Aim Verification of dose distributions for gynecological (GYN) brachytherapy implants using EBT Gafchromic film. Background One major challenge in brachytherapy is to verify the accuracy of dose distributions calculated by a treatment planning system. Materials and methods A new phantom was designed and fabricated using 90 slabs of 18 cm � 16 cm � 0.2 cm Perspex to accommodate a tandem and Ovoid assembly, which is normally used for GYN brachytherapy treatment. This phantom design allows the use of EBT Gafchromic films for dosimetric verification of GYN implants with a cobalt-60 HDR system or a LDR Cs-137 system. Gafchromic films were exposed using a plan that was designed to deliver 1.5 Gy of dose to 0.5 cm distance from the lateral surface of ovoids from a pair of ovoid assembly that was used for treatment vaginal cuff. For a quantitative analysis of the results for both LDR and HDR systems, the measured dose values at several points of interests were compared with the calculated data from a commercially available treatment planning system. This planning system was utilizing the TG-43 formalism and parameters for calculation of dose distributions around a brachytherapy implant. Results The results of these investigations indicated that the differences between the calculated and measured data at different points were ranging from 2.4 to 3.8 for the LDR Cs-137 and HDR Co-60 systems, respectively. Conclusion The EBT Gafchromic films combined with the newly designed phantom could be utilized for verification of the dose distributions around different GYN implants treated with either LDR or HDR brachytherapy procedures. © 2016 Greater Poland Cancer Centr

Salvage Brachytherapy for Biochemically Recurrent Prostate Cancer following Primary Brachytherapy

. Purpose. In this study, we evaluated our experience with salvage brachytherapy after discovery of biochemical recurrence after a prior brachytherapy procedure. Methods and Materials. From 2001 through 2012 twenty-one patients treated by brachytherapy within University of Kentucky or from outside centers developed biochemical failure and had no evidence of metastases. Computed tomography (CT) scans were evaluated; patients who had an underseeded portion of their prostate were considered for reimplantation. Results. The majority of the patients in this study (61.9%) were low risk and median presalvage PSA was 3.49 (range 17.41-1.68). Mean follow-up was 61 months. At last follow-up after reseeding, 11/21 (52.4%) were free of biochemical recurrence. There was a trend towards decreased freedom from biochemical recurrence in low risk patients ( = 0.12). International Prostate Symptom Scores (IPSS) increased at 3-month follow-up visits but decreased and were equivalent to baseline scores at 18 months. Conclusions. Salvage brachytherapy after primary brachytherapy is possible; however, in our experience the side-effect profile after the second brachytherapy procedure was higher than after the first brachytherapy procedure. In this cohort of patients we demonstrate that approximately 50% oncologic control, low risk patients appear to have better outcomes than others

Longitudinal clinical, cognitive and biomarker profiles in dominantly inherited versus sporadic early-onset Alzheimer's disease

Approximately 5% of Alzheimer's disease cases have an early age at onset (<65 years), with 5-10% of these cases attributed to dominantly inherited mutations and the remainder considered as sporadic. The extent to which dominantly inherited and sporadic early-onset Alzheimer's disease overlap is unknown. In this study, we explored the clinical, cognitive and biomarker profiles of early-onset Alzheimer's disease, focusing on commonalities and distinctions between dominantly inherited and sporadic cases. Our analysis included 117 participants with dominantly inherited Alzheimer's disease enrolled in the Dominantly Inherited Alzheimer Network and 118 individuals with sporadic early-onset Alzheimer's disease enrolled at the University of California San Francisco Alzheimer's Disease Research Center. Baseline differences in clinical and biomarker profiles between both groups were compared using t-tests. Differences in the rates of decline were compared using linear mixed-effects models. Individuals with dominantly inherited Alzheimer's disease exhibited an earlier age-at-symptom onset compared with the sporadic group [43.4 (SD ± 8.5) years versus 54.8 (SD ± 5.0) years, respectively, P < 0.001]. Sporadic cases showed a higher frequency of atypical clinical presentations relative to dominantly inherited (56.8% versus 8.5%, respectively) and a higher frequency of APOE-ϵ4 (50.0% versus 28.2%, P = 0.001). Compared with sporadic early onset, motor manifestations were higher in the dominantly inherited cohort [32.5% versus 16.9% at baseline (P = 0.006) and 46.1% versus 25.4% at last visit (P = 0.001)]. At baseline, the sporadic early-onset group performed worse on category fluency (P < 0.001), Trail Making Test Part B (P < 0.001) and digit span (P < 0.001). Longitudinally, both groups demonstrated similar rates of cognitive and functional decline in the early stages. After 10 years from symptom onset, dominantly inherited participants experienced a greater decline as measured by Clinical Dementia Rating Sum of Boxes [3.63 versus 1.82 points (P = 0.035)]. CSF amyloid beta-42 levels were comparable [244 (SD ± 39.3) pg/ml dominantly inherited versus 296 (SD ± 24.8) pg/ml sporadic early onset, P = 0.06]. CSF phosphorylated tau at threonine 181 levels were higher in the dominantly inherited Alzheimer's disease cohort (87.3 versus 59.7 pg/ml, P = 0.005), but no significant differences were found for t-tau levels (P = 0.35). In summary, sporadic and inherited Alzheimer's disease differed in baseline profiles; sporadic early onset is best distinguished from dominantly inherited by later age at onset, high frequency of atypical clinical presentations and worse executive performance at baseline. Despite these differences, shared pathways in longitudinal clinical decline and CSF biomarkers suggest potential common therapeutic targets for both populations, offering valuable insights for future research and clinical trial design

Longitudinal clinical, cognitive and biomarker profiles in dominantly inherited versus sporadic early-onset Alzheimer's disease

Approximately 5% of Alzheimer's disease cases have an early age at onset (<65 years), with 5-10% of these cases attributed to dominantly inherited mutations and the remainder considered as sporadic. The extent to which dominantly inherited and sporadic early-onset Alzheimer's disease overlap is unknown. In this study, we explored the clinical, cognitive and biomarker profiles of early-onset Alzheimer's disease, focusing on commonalities and distinctions between dominantly inherited and sporadic cases. Our analysis included 117 participants with dominantly inherited Alzheimer's disease enrolled in the Dominantly Inherited Alzheimer Network and 118 individuals with sporadic early-onset Alzheimer's disease enrolled at the University of California San Francisco Alzheimer's Disease Research Center. Baseline differences in clinical and biomarker profiles between both groups were compared using t-tests. Differences in the rates of decline were compared using linear mixed-effects models. Individuals with dominantly inherited Alzheimer's disease exhibited an earlier age-at-symptom onset compared with the sporadic group [43.4 (SD +/- 8.5) years versus 54.8 (SD +/- 5.0) years, respectively, P < 0.001]. Sporadic cases showed a higher frequency of atypical clinical presentations relative to dominantly inherited (56.8% versus 8.5%, respectively) and a higher frequency of APOE-epsilon 4 (50.0% versus 28.2%, P = 0.001). Compared with sporadic early onset, motor manifestations were higher in the dominantly inherited cohort [32.5% versus 16.9% at baseline (P = 0.006) and 46.1% versus 25.4% at last visit (P = 0.001)]. At baseline, the sporadic early-onset group performed worse on category fluency (P < 0.001), Trail Making Test Part B (P < 0.001) and digit span (P < 0.001). Longitudinally, both groups demonstrated similar rates of cognitive and functional decline in the early stages. After 10 years from symptom onset, dominantly inherited participants experienced a greater decline as measured by Clinical Dementia Rating Sum of Boxes [3.63 versus 1.82 points (P = 0.035)]. CSF amyloid beta-42 levels were comparable [244 (SD +/- 39.3) pg/ml dominantly inherited versus 296 (SD +/- 24.8) pg/ml sporadic early onset, P = 0.06]. CSF phosphorylated tau at threonine 181 levels were higher in the dominantly inherited Alzheimer's disease cohort (87.3 versus 59.7 pg/ml, P = 0.005), but no significant differences were found for t-tau levels (P = 0.35). In summary, sporadic and inherited Alzheimer's disease differed in baseline profiles;sporadic early onset is best distinguished from dominantly inherited by later age at onset, high frequency of atypical clinical presentations and worse executive performance at baseline. Despite these differences, shared pathways in longitudinal clinical decline and CSF biomarkers suggest potential common therapeutic targets for both populations, offering valuable insights for future research and clinical trial design