The development of an object-oriented classification model for operational burned area mapping on the Mediterranean island of Thasos using Landsat TM images

ABSTRACT: Multispectral classification, one of the most commonly used methods for mapping burned areas, is based on the spectral properties of different classes of interest and employs special algorithms designed to perform various types of spectral analysis. However, the use of these classifications has been repeatedly reported to create confusion between burned areas and nonvegetation categories, especially water bodies and shaded areas. As a result of the aforementioned, spectral based classification methods cannot be used operationally for the mapping of burned areas from satellite images. On the other hand, object-oriented image classification, which is based on fuzzy logic, allows the integration of a broad spectrum of different object features, such as spectral values, shape and texture. Sophisticated classification, incorporating contextual and semantic information, can be performed by utilizing not only image object attributes but also the relationship between networked image objects. In this study the synergy of all these features allowed us to address image analysis tasks that, up till now, have not been possible. The aim of this work was to develop an object-oriented classification model for operational burned area mapping on the Mediterranean island of Thasos using LANDSAT TM images. An objectoriented specified model was used to map burned areas in two different Mediterranean areas after the LANDSAT TM images had been radiometrically, geometrically and topographically corrected. The combination of the object-oriented approach and the multispectral resolution data of LANDSAT TM showed very promising results in burned area mapping and in discriminating between burned and the other classes of confusion

Soil patterns as a factor of crop heterogeneity

This paper examines the relationship between the heterogeneity of different crops in the Tula region of the Russian Federation based on vegetation observations during the period 2015-2020 with the mapping units of a large (scale 1:10,000) soil map. NDVI values calculated from Sentinel-2 satellite data were used as a measure of crop heterogeneit

Investigation of aggregation effects in vegetation condition monitoring at a national scale

Abstract Monitoring vegetation condition is an important issue in the Mediterranean region, in terms of both securing food and preventing fires. Vegetation indices (VIs), mathematical transformations of reflectance bands, have played an important role in vegetation monitoring, as they depict the abundance and health of vegetation. Instead of storing raster VI maps, aggregated statistics can be derived and used in long-term monitoring. The aggregation schemes (zonations) used in Greece are the forest service units, the fire service units and the administrative units. The purpose of this work was to explore the effect of the Modifiable Areal Unit Problem (MAUP) in vegetation condition monitoring at the above mentioned aggregation schemes using 16day Normalized Difference Vegetation Index (NDVI) composites acquired by the MODIS (Moderate Resolution Imaging Spectroradiometer) satellite sensor. The effects of aggregation in the context of MAUP were examined by analyzing variance, from which the among polygon variation (objects' heterogeneity) and the within polygon variation (pixels' homogeneity) was derived. Significant differences in objects' heterogeneity were observed when aggregating at the three aggregation schemes, therefore there is a MAUP effect in monitoring vegetation condition on a nationwide scale in Greece with NDVI. Monitoring using the fire service units has significantly higher pixels' homogeneity, therefore there is indication that it is the most appropriate for monitoring vegetation condition on a nationwide scale in Greece with NDVI. Results were consistent between the two major types of vegetation, natural and agricultural. According to the statistical validation, conclusions based on the examined years (2003 and 2004) are justified

Accuracy of the Triple Test Versus Colposcopy for the Diagnosis of Premalignant and Malignant Cervical Lesions

Background: Despite the World Health Organization (WHO) recommendations concerning the use of alternative tests for the detection of cervical cancer precursor lesions in low-income countries, the accuracy of these tests is a debated issue. In the present study we compare the diagnostic accuracy of the triple test with that of colposcopy for the diagnosis of premalignant and malignant cervical lesions. Methods: A cross-sectional study was performed in 328 women referred to the gynecology clinic at Shahid Sadoughi Hospital, affiliated to Yazd University of Medical Sciences (SSUMS), Yazd, Iran, from March 2016 to June 2018. As the first step, a Pap smear was obtained from all participants. Visual inspection with acetic acid (VIA) and Lugol�s iodine (VILI) was performed in accordance with the known protocol. A colposcopy was then conducted in all participants, biopsy samples were obtained, and histological features studied. Finally, the results were compared by statistical analysis. Results: The age range of the participants was 30 - 50 years. Of 328 women, 60 (18.3 ) were postmenopausal. Two-hundred and five patients (62.5 ) had an abnormal Pap smear, 165 (50.3 ) had abnormal results on colposcopy, and 141 (43 ) had abnormal histopathology reports. The VIA was positive in 129 patients (39.3 ) and the VILI in 177 (54 ). The results of the triple test were reported to be positive in 205 cases (51.52 ). The sensitivity of the triple test in the detection of premalignant and malignant cervical lesions was 78.7 and 69 , respectively. The sensitivity and specificity of colposcopy in the detection of premalignant and malignant cervical lesions was 80.1 and 72.2 , respectively. The diagnostic accuracy of the triple test and colposcopy in the detection of premalignant and malignant cervical lesions was 73 versus 75 . Conclusion: Since the results of the study showed that the diagnostic accuracy of the triple test is equivalent that of colposcopy, the former may be used in low-income countries and areas lacking access to colposcopy. © 2020. All rights reserved

Influence of the second stage of labor on maternal and neonatal outcomes in vaginal births after caesarean section: a multicenter study in Germany

Background: The American College of Obstetricians and Gynecologists (ACOG) introduced a new standard of care in 2014, extending the duration of the second stage of labor in order to reduce caesarean delivery (CD) rates and its severe complications. The aim of the present study is to evaluate success rates of trial of labor after caesarean section (TOLAC), as well as maternal and neonatal outcomes after the establishment of the recent guidelines. Methods: A retrospective study was performed at two large departments in Germany from January 2008 to January 2018. Patients undergoing TOLAC were divided into two groups. Group I (958 patients) was constituted before the establishment of the current guidelines, and Group II (588 patients) after the establishment of the guidelines. A subgroup analysis was performed to compare neonatal outcomes after successful TOLAC and operative vaginal delivery with those after failed TOLAC and secondary CD. Results: The success rate of vaginal births after cesarean section (VBAC) fell from 66.4 in Group I to 55.8 in Group II (p < 0.001). The median duration of the second stage of labor was statistically significantly longer in Group II than in Group I (79.3 ± 61.9 vs. 69.3 ± 58.2 min) for patients without previous vaginal birth. The incidence of operative vaginal delivery decreased from Group I to Group II (9.6 vs. 6.8). The incidence of third- and fourth-degree perineal lacerations, blood loss and emergency CD were similar in the two groups. Concerning the neonatal outcome, our groups did not differ significantly in regard of rates of umbilical artery cord pH < 7.1 (p = 0.108), the 5-min Apgar scores below 7 (p = 0.224) and intubation (p = 0.547). However, the transfer rates to the neonatal care unit were significantly higher in Group II than in Group I (p < 0.001). Neonatal outcomes did not differ significantly in the subgroup analysis. Conclusion: Extending the second stage of labor does not necessarily result in more vaginal births after TOLAC. Maternal and neonatal outcomes were similar in both groups. Further studies will be needed to evaluate the role of operative vaginal delivery and the duration of the second stage of labor in TOLAC. © 2021, The Author(s)

Spatial determinants of land-use changes in an urban region (Attica, Greece) between 1987 and 2007

The present study investigates the relationship between the use of land and selected spatial determinants of change in a Mediterranean urban region (Attica, Greece). A multi-temporal analysis was developed to assess the influence of population density, sealing intensity, distances from roads and from the main urban centre, land protection regime, municipality surface area, elevation, climate aridity, soil characteristics and sensitivity of land to degradation on changes in the spatial distribution of nine land-use classes derived from LANDSAT imagery for 1987 and 2007. Artificial, bare and burnt land increased in the last 20 years with the consequent decline in land-use quality and landscape diversification. Rain-fed crop and sparsely vegetated areas experienced the highest probability to edification. Elevation, population density, the distance from the centre of Athens and from the main roads were the variables affecting the most rapid changes in the use of land. Multivariate analysis allows identifying the most relevant spatial determinants of land-use changes as a target for environmental policies against land consumption in expanding urban regions

Spatial determinants of land-use changes in an urban region (Attica, Greece) between 1987 and 2007

The present study investigates the relationship between the use of land and selected spatial determinants of change in a Mediterranean urban region (Attica, Greece). A multi-temporal analysis was developed to assess the influence of population density, sealing intensity, distances from roads and from the main urban centre, land protection regime, municipality surface area, elevation, climate aridity, soil characteristics and sensitivity of land to degradation on changes in the spatial distribution of nine land-use classes derived from LANDSAT imagery for 1987 and 2007. Artificial, bare and burnt land increased in the last 20 years with the consequent decline in land-use quality and landscape diversification. Rain-fed crop and sparsely vegetated areas experienced the highest probability to edification. Elevation, population density, the distance from the centre of Athens and from the main roads were the variables affecting the most rapid changes in the use of land. Multivariate analysis allows identifying the most relevant spatial determinants of land-use changes as a target for environmental policies against land consumption in expanding urban regions