Patterns of nodal spread in stage III NSCLC: importance of EBUS-TBNA and 18F-FDG PET/CT for radiotherapy target volume definition

Purpose The aim of this study was to compare the pattern of intra-patient spread of lymph-node (LN)-metastases within the mediastinum as assessed by 18F-FDG PET/CT and systematic endobronchial ultrasound-guided transbronchial-needle aspiration (EBUS-TBNA) for precise target volume definition in stage III NSCLC. Methods This is a single-center study based on our preceding investigation, including all consecutive patients with initial diagnosis of stage IIIA-C NSCLC, receiving concurrent radiochemotherapy (12/2011–06/2018). Inclusion criteria were curative treatment intent, 18F-FDG PET/CT and EBUS-TBNA prior to start of treatment. The lymphatic drainage was classified into echelon-1 (ipsilateral hilum), echelon-2 (ipsilateral LN-stations 4 and 7) and echelon-3 (rest of the mediastinum, contralateral hilum). The pattern of spread was classified according to all permutations of echelon-1, echelon-2, and echelon-3 EBUS-TBNA findings. Results In total, 180 patients were enrolled. Various patterns of LN-spread could be identified. Skip lesions with an involved echelon distal from an uninvolved one were detected in less than 10% of patients by both EBUS-TBNA and PET. The pattern with largest asymmetry was detected in cases with EBUS-TBNA- or PET-positivity at all three echelons (p < 0.0001, exact symmetry test). In a multivariable logistic model for EBUS-positivity at echelon-3, prognostic factors were PET-positivity at echelon-3 (Hazard ratio (HR) = 12.1; 95%-CI: 3.2–46.5), EBUS-TBNA positivity at echelon-2 (HR = 6.7; 95%-CI: 1.31–31.2) and left-sided tumor location (HR = 4.0; 95%-CI: 1.24–13.2). There were significantly less combined ipsilateral upper (LN-stations 2 and 4) and lower (LN-station 7) mediastinal involvements (16.8% of patients) with EBUS-TBNA than with PET (38.9%, p < 0.0001, exact symmetry test). EBUS-TBNA detected a lobe specific heterogeneity between the odds ratios of LN-positivity in the upper versus lower mediastinum (p = 0.0021, Breslow-Day test), while PET did not (p = 0.19). Conclusion Frequent patterns of LN-metastatic spread could be defined by EBUS-TBNA and PET and discrepancies in the pattern were seen between both methods. EBUS-TBNA showed more lobe and tumor laterality specific patterns of LN-metastases than PET and skipped lymph node stations were rare. These systematic relations offer the opportunity to further refine multi-parameter risk of LN-involvement models for target volume delineation based on pattern of spread by EBUS-TBNA and PET.

Higher Number of Yeast-like Fungi in the Air in 2018 after an Emergency Discharge of Raw Sewage to the Gulf of Gdańsk—Use of Contingency Tables

This study aimed to investigate the differences between the number of yeast-like fungi and molds in the coastal air of five coastal towns of the Gulf of Gdańsk in 2014–2017 vs. 2018, which saw an emergency discharge of sewage. In 2014–2017, a total of 62 duplicate samples were collected in the coastal towns of Hel, Puck, Gdynia, Sopot, and Gdańsk-Brzeźno. In 2018, after the emergency disposal of raw sewage, 26 air samples were collected. A Pearson chi-squared test of independence showed that during 2018 in Hel and Sopot, the mean number of molds and yeast-like fungi was higher than in 2014–2017. The result was significantly positive, p ≤ 2.22 × 10−16. The analysis of the General Asymptotic Symmetry Test showed that in Puck and Gdańsk-Brzeźno, the average number of Aspergillus sp. mold fungi was higher in 2018 after an emergency discharge of sewage into the Gulf of Gdańsk compared to the period 2014–2017. The result was not statistically significant. In addition, the average number of Penicillium sp. molds in 2018 in Gdańsk-Brzeźno was higher than in 2014–2017, but statistically insignificant (p = 0.9593). In 2018, the average number of Cladosporium sp. molds in Sopot was higher, but also statistically insignificant (p = 0.2114) compared to 2014–2017. Our results indicate that the study of the number of yeast-like fungi in the air may indicate coastal areas that may be particularly at risk of bacterial or mycological pathogens, e.g., after an emergency discharge of raw sewage.

A Novel Method of Hyperbola Recognition in Ground Penetrating Radar (GPR) B-Scan Image for Tree Roots Detection

Ground penetrating radar (GPR), as a newly nondestructive testing technology (NDT), has been adopted to explore the spatial position and the structure of the tree roots. Due to the complexity of soil distribution and the randomness of the root position in the natural environment, it is difficult to locate the root in the GPR B-Scan image. In this study, a novel method for root detection in the B-scan image by considering both multidirectional features and symmetry of hyperbola was proposed. Firstly, a mixed dataset B-Scan images were employed to train Faster RCNN (Regions with CNN features) to obtain the potential hyperbola region. Then, the peak area and its connected region were filtered from the four directional gradient graphs in the proposed region. The symmetry test was applied to segment the intersecting hyperbolas. Finally, two rounds of coordinate transformation and line detection based on Hough transform were employed for the hyperbola recognition and root radius and position estimation. To validate the effectiveness of this approach for tree root detection, a mixed dataset was made, including synthetic data from gprMax as well as field data collected from 35 ancient tree roots and fresh grapevine controlled experiments. From the results of hyperbola recognition as well as the estimation for the radius and position of the root, our method shows a significant effect in root detection.

Supplemental Material: Deformation-induced Japan twinning in quartz during incipient mylonitization

Methods, twinning in quartz, and Japan-Law twin symmetry test.<br>

Supplemental Material: Deformation-induced Japan twinning in quartz during incipient mylonitization

Methods, twinning in quartz, and Japan-Law twin symmetry test.<br>

Topical Estrogen, Testosterone, and Vaginal Dilator in the Prevention of Vaginal Stenosis after Radiotherapy in Women with Cervical Cancer

Background: we aimed to evaluate the effects of different therapeutic options to prevent the evolution of vaginal stenosis after pelvic radiotherapy in women with cervical cancer. Methods: open-label randomized clinical trial of 195 women, stage I-IIIB, aged 18-75 years, using topical estrogen (66), topical testosterone (34), water-based intimate lubricant gel (66), and vaginal dilators (29) to assess the incidence and severity of vaginal stenosis after radiotherapy at UNICAMP-Brazil, from January/2013 to May/2018. The main outcome measure was vaginal stenosis assessed using the Common Terminology Criteria for Adverse Events (CTCAE) scale and percental changes in vaginal volume. The women were evaluated at four different times: shortly after the end of radiotherapy, and four, eight, and 12 months after the beginning of the intervention. Statistical analysis was carried out using Symmetry test, Kruskal-Wallis test and multiple regression. Results: the mean age of women was 46.78 (±13.01) years, 61,03% were premenopausal and 73,84% had stage IIB-IIIB tumors. The mean reduction in vaginal volume in the total group was 25.47%, with similar worsening in the four treatment groups with no statistical difference throughout the intervention period. There was worsening of vaginal stenosis evaluated by CTCAE scale after 1 year in all groups (p<0.01), except for the users of vaginal dilator (p=0.37). Conclusions: there was a reduction in vaginal volume in all treatment groups analyzed, with no significant difference between them. However, women who used vaginal dilators had a lower frequency and severity of vaginal stenosis assessed by the CTCAE scale after one year of treatment.Trial registration: Brazilian Registry of Clinical Trials, RBR-23w5fv. Registered 10 January 2017 - Retrospectively registered, https://ensaiosclinicos.gov.br/rg/RBR-23w5fv

Emergence of reflexivity relation without identity matching-to-sample training in hooded crows (Corvus cornix)

The ability to form equivalent relations between sign and referent—symbolization—is one of the important cognitive components of language. Equivalent relations have the properties of symmetry (if A→B then B→A), reflexivity (A→A, B→B), and transitivity (if A→B and B→C, then A→C). The current study evaluates whether reflexivity can be spontaneously revealed in hooded crows (Corvus cornix) without training after the formation of the symmetry relation. These birds were previously taught an arbitrary matching-to-sample task with the letters “S” and “V” as samples, and sets of images (same-sized and different-sized figures) as comparisons. Positive results in the transfer tests showed that the crows associated letters with the concepts of sameness/difference. After that, they successfully passed the symmetry test, in which samples and comparisons were switched around. In the present experiment we found out that the crows passed the reflexivity test (A→A, B→B) without identity training. We hypothesize that if the subject associates the sample not with certain stimuli but rather with concepts, it facilitates the formation of equivalence relations between them.