Search

The objective of the study is to conduct a comprehensive examination of how different neighbourhood types, namely spherical, cylindrical, and k-nearest neighbour (kNN), influence the feature extraction capabilities of the PointNet++ architecture in the semantic segmentation of Airborne Laser Scanning (ALS) point clouds. Two datasets are utilized for semantic segmentation analysis: the Dayton Annotated LiDAR Earth Scan (DALES) and the ISPRS 3D Semantic Labelling Benchmark datasets. In the experiments, the kNN method exhibited approximately 1% higher accuracy in weighted mean F1 and intersection over union (IoU) metrics compared to the spherical and cylindrical neighbourhood types on the DALES dataset. However, in the generalization experiment conducted on the ISPRS dataset, the spherical neighbourhood achieved the best results in these metrics, outperforming the cylindrical neighbourhood by a small margin. Notably, the kNN method was the least accurate, with a decrease in accuracy of approximately 1% in both weighted mean IoU and F1 scores. These findings suggest that the features extracted from spherical and cylindrical neighbourhood types are more generalizable compared to those from the kNN method. [ABSTRACT FROM AUTHOR]

The automatic extraction of objects from airborne laser scanner data and images has been a topic of research for decades. Laser scanner data have proven to be a powerful source for a wide range of 2D-3D geographic information system object tasks. This paper presents the Fourier transform as an image enhancement tool for determination of buildings from the images generated by laser signal. Spatial and frequency domain filtering techniques have been utilized for extraction of building from enhanced images. While Gaussian and Wiener filterings were selected in frequency domain, Sobel and Unsharp were selected for the spatial domain. The boundaries of buildings have been delineated from the generated images, which were obtained from inverse Fourier transform, by using edge detectors, such as Canny, Sobel, and Prewitt. Frequency domain filters using Fourier transformation were compared with spatial domain filters in the way of kernel function and windows. The reason for doing the filtering in the frequency domain is that it is computationally faster to perform two-dimensional Fourier transforms and a filter is more applicable than to perform a convolution in the spatial domain. Results showed that using Fourier transformation has a great advantage in enhancing images and detecting the buildings on images. Filtering in the frequency domain is more efficient computationally than spatial domain filtering when the filter size is big. The conclusion proved that Fourier transformation can be used as an image enhancement tool to detect and extract buildings automatically. [ABSTRACT FROM AUTHOR]

Urbanization often incurs environmental costs, as fertile agricultural and forested lands are converted into urban areas. Herat City is currently undergoing significant urban transformation. This research aims to assess the impact of urban sprawl on Herat City's urban ecological status during 2000, 2013, and 2021, using GIS and remote sensing. The urban expansion intensity index was used to measure urban sprawl. The Mean Remote Sensing Ecological Index (MRSEI), integrating known granulation entropy (KGE) and comprehensive distance-based ranking (COBRA) algorithms, was utilized to evaluate urban ecological status. The random forest (RF) supervised machine learning-based algorithm was used to classify the study area into four categories (Built-up, Bare-land, Water, and Vegetation). Findings indicate rapid development from 2000 to 2013, followed by moderate expansion until 2021. Urban ecological quality degradation is observed in various directions over time, with the southeast consistently demonstrating excellent status. Interestingly, while good and excellent urban ecological status decreases over two decades, poor and very poor conditions improve. The research underscores an inverse relationship between urban expansion intensity and ecological status, highlighting the need for improved strategies to mitigate environmental decline. These findings will inform Afghan governmental bodies and international organizations, enabling them to better address resource consumption, ecological disruptions, social inequalities, and foster sustainable development., Competing Interests: Declarations. Ethical approval: All authors have read, understood, and have complied as applicable with the statement on “Ethical responsibilities of Authors” as found in the Instructions for Authors. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Objective: To investigate the involvement of lymph nodes in para-aortic (PA) region particularly above and below the inferior mesenteric artery (IMA) in patients with endometrial cancer who had complete systemic pelvic and PA lymphadenectomy., Methods: A total of 165 consecutive patients with endometrial cancer surgically staged from January 2008 to March 2011 in the gynecologic oncology unit of a tertiary maternity center, Zekai Tahir Burak Hospital, Ankara, Turkey, were included retrospectively. All patients had complete pelvic and PA lymphadenectomy., Results: Nineteen women had any metastasis in pelvic and/or PA region. Twelve women (7.3%) had only pelvic, 5 women (3%) had both pelvic and PA, and 2 women had isolated PA metastasis. There were 6 patients (3.7%) with PA nodal metastasis above the IMA. Four patients with PA node involvement had positive nodes above the IMA without any metastasis below the IMA. In binary logistic regression analysis, PA metastasis above the IMA was associated with lymphovascular space invasion, pelvic metastasis, and tumor size., Conclusions: Isolated PA metastasis is rare in endometrial cancer. If pelvic nodes are involved, PA metastasis is likely, and PA lymphadenectomy should be performed up to renal vessels so as not to miss occult metastasis in higher regions particularly above the IMA.

Coastline mapping and coastline change detection are critical issues for safe navigation, coastal resource management, coastal environmental protection, and sustainable coastal development and planning. Changes in the shape of coastline may fundamentally affect the environment of the coastal zone. This may be caused by natural processes and/or human activities. Over the past 30 years, the coastal sites in Turkey have been under an intensive restraint associated with a population press due to the internal and external touristic demand. In addition, urbanization on the filled up areas, settlements, and the highways constructed to overcome the traffic problems and the other applications in the coastal region clearly confirm an intensive restraint. Aerial photos with medium spatial resolution and high resolution satellite imagery are ideal data sources for mapping coastal land use and monitoring their changes for a large area. This study introduces an efficient method to monitor coastline and coastal land use changes using time series aerial photos (1973 and 2002) and satellite imagery (2005) covering the same geographical area. Results show the effectiveness of the use of digital photogrammetry and remote sensing data on monitoring large area of coastal land use status. This study also showed that over 161 ha areas were filled up in the research area and along the coastal land 12.2 ha of coastal erosion is determined for the period of 1973 to 2005. Consequently, monitoring of coastal land use is thus necessary for coastal area planning in order to protecting the coastal areas from climate changes and other coastal processes.

Objective: The goal of this study was to determine the role of gadolinium-enhanced 3D MR angiography (MRA) in patients with suspected pulmonary hypoplasia and aplasia in a retrospective analysis of MRA and digital subtraction angiography in 11 patients with clinical and/or radiologic suspicion of pulmonary hypoplasia and aplasia., Conclusion: Gadolinium-enhanced 3D MRA is capable of diagnosing pulmonary hypoplasia and aplasia rapidly and accurately. Both pulmonary hypoplasia and aplasia can be shown morphologically in a noninvasive manner, obviating digital subtraction angiography.

The relative role of different adhesion molecules in the ischemia-reperfusion injury after cardioplegic arrest in the clinical setting is unknown, because of protective effects of cardioplegia and hypothermia. The aim of this study is to determine the relationship between the method of the cardioplegia and endothelial derived soluble adhesion molecules; soluble vascular adhesion molecule-1 (sVCAM-1) and soluble intercellular adhesion molecule-1 (sICAM-1) in myocardial ischemia- reperfusion injury. Fourteen male patients who underwent aortocoronary bypass surgery with cardiopulmonary bypass were included in this study. They were randomised to be given blood or crystalloid cardioplegia for myocardial protection. Group I (n=7) received blood cardioplegia and group II (n=7) received crystalloid cardioplegia. The cross-clamp times were not significantly different between the two groups, 49.4+/-4.6 min for group I and 54.8+/-2.5 min for group II. Mean age of patients was 58+/-2.1 years for group I and 54+/-2.6 years for group II. Blood samples were taken from both the aorta and coronary sinuses of all patients before cross-clamp, after cross-clamping and at 30th min of reperfusion. Plasma were obtained from blood samples and then stored at -70 degrees C. sVCAM-1 and sICAM-1 levels were measured by ELISA in the samples. There were no significant differences in the levels of sICAM-1 and sVCAM-1 at the beginning of reperfusion and at 30th min of reperfusion in coronary sinus of group I patients. But, increased sICAM-1 and sVCAM-1 levels were observed at 30th min of reperfusion in blood taken from coronary sinuses of group II patients compared with beginning of reperfusion (respectively p=0.01, p=0.03). In conclusion, these results have shown that ischemia-reperfusion injury is more likely to occur in patients protected by crystalloid cardioplegia, and suggest that blood cardioplegia may be preferred especially in borderline myocardial functioned patients.

Objective: Increased numbers of spontaneous Ig secreting B cells and elevated immunoglobulin levels have been described in Behçet's disease (BD), in addition to changes in numbers and activities of T cells, natural killer cells, and monocyte-macrophages. We investigated other characteristics of B cells in BD., Methods: B lymphocyte subsets (CD19+CD5+, CD19+CD13+, CD19+CD28+, CD19+CD33+, CD19+CD80+, CD5+CD19+CD45RA+, CD5+CD19+CD45RO+) were phenotypically evaluated in 50 patients with BD, 80 healthy subjects, and 20 other patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and sepsis., Results: Although the B cell number (CD19+) was normal, CD13 and CD33 positive B cells were more numerous in BD and sepsis compared to healthy controls and patients with RA and SLE. The percentage of CD45RO positive B cells was higher in both BD and sepsis, while the percentage of CD80 positive B cells was high only in BD. There was no increase in the CD5+CD19+ B cell subset, previously shown to be increased in several autoimmune diseases. Naive (CD45RA) and memory (CD45RO) status of CD5+CD19+ and CD5-CD19+ B cells showed that CD45RA expression was higher in CD5+CD19+ B cells, whereas expression of both CD45RA and CD45RO was higher in the CD5-CD19+ B cell group compared with healthy controls., Conclusion: Although the total B cell number was normal, increased levels of activated and memory B cell subsets suggest a modified B cell function in BD, which may be related to a weak stimulus by an unknown external antigen.

We prospectively studied 26 patients with cold thyroid nodules (five malignant and 21 benign nodules) on Tc-99m pertechnetate scintigraphy to investigate the diagnostic value of Tc-99m tetrofosmin scintigraphy and color-Doppler sonography in differentiating malignant from benign thyroid nodules. In each patient, Tc-99m Tetrofosmin uptake in the nodule and intranodule vascularity were assessed semiquantatively. Both the uptake and vascularity were classified as low, Iso or high. Eight out of 26 nodules showed high Tc-99m tetrofosmin uptake; five of them were malignant. Eight (including four malignant tumors) out of 26 nodules showed increased vascularity compared with normal thyroid tissue on color-Doppler sonography. In six out of eight patients with high uptake of Tc99m-tetrofosmin, increased vascularity was observed. The sensitivity, specificity, negative predictive value, and positive predictive value of Tc-99m tetrofosmin scintigraphy and color-Doppler sonography were determined to be 100% and 80%, 85% and 80%, 62% and 50%, and 100% and 94%, respectively. We conclude that color-Doppler sonography seems to have limited value in the detection of malignant thyroid nodules. However, Tc-99m tetrofosmin scintigraphy is a sensitive method to use in diagnosing malignant nodules, although it is not specific for the detection of malignant nodules.