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Compact polarimetry has gained popularity due to its advantages, such as larger swath, simple architecture and low power consumption. The backscattered signal and scattering decomposition vary for different targets based on their electrical, geometrical and structural properties. As of now, the potential of hybrid polarimetric synthetic aperture radar (SAR) data for exploring Antarctic ice features is not fully explored. Here, we present a comprehensive polarimetric feature analysis and classification results of the hybrid polarimetric dataset acquired by RISAT-1 near the Indian Antarctic research station Maitri. The single-look complex images have been subjected to polarimetric data processing for extracting Antarctic ice features using POLSARPRO software. The polarimetric coherence matrix is generated and then filtered to eliminate speckles. Raney m-X decomposition technique has been utilized to understand the scattering mechanism of the targets. The decomposed RGB image is classified using Wishart-supervised classification, and classification accuracy is assessed using a confusion matrix. It is found that the comparatively simple hybrid polarimetric SAR provides sufficient information to detect and discriminate various Antarctic ice features. Features such as rifts, ice-rises, ice shelves and icebergs are clearly discriminated using Wishart-supervised classification. It is also found that the overall accuracy of the classification of study areas varies between 80% and 97%, suggesting a good classification outcome. [ABSTRACT FROM AUTHOR]

We have monitored the changes that have occurred over nine Antarctic ice shelves between 1997 and 2019 using Sentinel-1 and RADARSAT-1 images of Antarctica using change detection technique. The net loss of Antarctic ice shelves during the period was about 14,723 sq. km in surface area, corresponding to 1.21% area of ice shelves. The Ross and Filchner-Ronne ice shelves retreated significantly in terms of total area, while shelves in that Antarctic Peninsula, namely Wilkins and Larsen C retreated drastically in terms of percentage change. [ABSTRACT FROM AUTHOR]

This article explores some interactive aggregation operators for Fermatean fuzzy sets (FFS). These operators are generalisations of those defined for intuitionistic fuzzy sets. It revises the existing operational rules for Fermatean Fuzzy Numbers (FFNs) to construct interactive aggregation operators for FFSs. The improved operational rules incorporate the effects of the membership and non-membership values of the operand FFNs on the resulting FFN. Based on the weighted arithmetic mean and weighted geometric mean, this article proposes two aggregation operators, namely, the Fermatean Fuzzy Interactive Weighted Averaging (FFIWA) operator and the Fermatean Fuzzy Interactive Weighted Geometric (FFIWG) operator. It discusses some properties of the proposed operators and develops an approach for Multi-Attribute Decision making (MADM) using these operators. A numerical example illustrates the developed approach, which is tested for validity using some evaluation criteria. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the concept of reversibility in frames. The relation between reversible spatial frames and reversible topological spaces is also studied. We also prove that the product of a two point discrete topological space and a reversible topological space is reversible which is posed by M. Rajagopalan and A. Wilansky. [ABSTRACT FROM AUTHOR]

Present study focuses on the utilization of Earth observation satellite-04 (EOS-04) synthetic aperture radar (SAR) data for maintaining the continuity of the first Indian radar imaging satellite (RISAT)-1 SAR derived products along with exploring the potential of capability of the improved sensor over mountain and polar cryospheric region. Backscattering coefficient (σ0) of various snow and ice features over mountain and polar cryosphere have been analysed to understand the interaction mechanism using C-band SAR data. EOS-04 is able to pick up the spatio-temporal variability of SAR backscatters over accumulation and ablation zone of the glacier due to melt-freeze cycles, and observations were in accordance with variation in elevations over the glacier surface. When analysed for Drang-Drung glacier, wet snow zone was found to be prominently centered around 5500 m elevation zone, having sigmanaught backscatter lower than –10 dB in the ablation months, whereas percolation zone was observed at more than 6000 m elevation with higher sigma-naught backscatter of around –4 dB and above as winter started setting in. EOS-04 also showed the potential to classify various polar ice features based on backscattering signature using HH (H, horizontal) (σ0), HV (V, vertical) (σ0) and normalized difference polarization ratio index (NDPRI) respectively. EOS-04 data have been used to implement approaches to retrieve wet snow cover and set up of Weather Research and Forecasting Model Hydrological Modelling System (WRF hydro) model for snow melt runoff studies, interaction mechanism of snow and ice, snow/ice facies extraction, ice shelf monitoring, sea ice properties and sea ice advisory for Indian scientific expedition to Antarctica. Enrichment of EOS-04 data, suitable for cryosphere studies, will be employed to retrieve parameters such as snowpack properties, elevation, ice surface velocities over mountain and polar region, and to further improve comprehensive understanding on regional and global frozen ice dynamics. [ABSTRACT FROM AUTHOR]

The article reports that huge portion of Larsen C ice shelf of around 50,000 km2 in Antarctic Peninsula had calved away to an iceberg of area close to 6,200 square Kilometers between 10 and 12 July 2017. after Filchner-Ronne,Ross and Amery ice shelves, Larsen C is fourth largest ice shelf in Antarctica.

Studies have already indicated more disintegrations and calving of ice margins and a significant negative ice balance at certain parts of Antarctica in recent times. Changes in extent of ice shelves as well as glacier fronts are indeed good signatures of climate change. This paper essentially discusses the changes in Antarctic ice margins between 1997 and 2016. Change-detection technique has been employed using the Radar Satellite (RADARSAT) mosaic of 1997 and the mosaic of Antarctic ice margins generated using MODerate resolution Imaging Satellite (MODIS) images of 2016, with the help of Earth Resources Development Assessment system (ERDAS) Imagine software. Hotspots, where significant changes occurred, have been identified. Most part of the Antarctic coast between 75° E and 45° W, covering all West Antarctica and about half of East Antarctica, has shown definite retreat during this period. Major retreats are observed over the both sides of Ross ice shelf, Ronne ice shelf, Thwaites glacier, and Mertz glacier. Major advancements are observed over Filchner ice shelf, Amery ice shelf, middle portion of Ross ice shelf, and Stancomwills glacier tongue. Over the East Antarctica, areas of advancement and retreat are nearly same. But, over the West Antarctica, the area of retreat is significantly higher than area of advancement. [ABSTRACT FROM AUTHOR]

Background: Although guidelines from multiple scientific studies decide the general trend in ACLR practice, there is often a variation between scientific guidelines and actual practice. Methods: A 17-member committee comprised of sports surgeons with experience of a minimum of 10 years of arthroscopy surgery finalized a survey questionnaire consisting of concepts in ACL tear management and perioperative trends, intraoperative and post-operative practices regarding single-bundle anatomic ACLR. The survey questionnaire was mailed to 584 registered sports surgeons in six states of south India. A single, non-modifiable response was collected from each member and analyzed. Results: 324 responses were received out of 584 members. A strong consensus was present regarding Hamstring tendons preference for ACLR, graft diameter ≥ 7.5 mm, viewing femoral footprint through the anterolateral portal, drilling femoral tunnel from anteromedial portal guided by ridges and remnants of femoral footprint using a freehand technique, suspensory devices to fix the graft in femur and interference screw in the tibia and post-operative bracing. A broad consensus was achieved in using a brace to minimize symptoms of instability of an ACL tear and antibiotic soaking of graft. There was no consensus regarding the timing of ACLR, preferred graft in athletes, pre-tensioning, extra-articular procedure, and return to sports. There was disagreement over hybrid tibial fixation and suture tapes to augment graft. Conclusion: Diverse practices continue to prevail in the management of ACL injuries. However, some of the consensuses reached in this survey match global practices. Contrasting or inconclusive practices should be explored for potential future research. [ABSTRACT FROM AUTHOR]

Antarctica is the focus of scientific studies considering the largest reservoir of terrestrial water in the form of ice and doubling of ice area during winter due to sea-ice growth. The third pole -- Himalaya is equally important due to the large extent of snow and ice cover outside the polar region, which is a major source of water for the Asian countries. At present, the Ku-band scatterometer observing global cryosphere is the SCATSAT-1 launched by India. This article describes the study carried out on different cryospheric parameters using high-resolution (~2.2 km) scatterometer data in the Antarctica and Himalaya. Impact of seasonal variations in snow/ice and ice calving on the backscatter over Antarctica is discussed in detail. A procedure developed for the estimation of sea-ice extent, which yielded overall accuracy of 89%, has been presented and successfully applied for daily monitoring of the Antarctic ice extent for 2017. Surface melting using backscatter and brightness temperature data has been discussed and the contrast between large-sized and small-sized Antarctic ice shelves during the austral summer period of summer 2017-18 is highlighted. The higher average surface melt observed around majority of east Antarctic ice shelves, particularly near the Indian station 'Maitri', is of particular interest. Typical surface melting patterns observed over the third largest Antarctic ice shelf, Amery, are discussed in detail. Over northwest Himalaya, derived changes in snow water equivalent (ΔSWE) shows a good correlation between observed and calculated SWE variations. The present study demonstrates that simultaneous availability of high-resolution brightness temperature and backscatter data from SCATSAT-1 provides a unique opportunity to study the polar and mountain cryosphere. [ABSTRACT FROM AUTHOR]

Abstract Cervical cancer (CC) is a major fatal health problem in women with high mortality worldwide. Human Papilloma Virus (HPV) is considered as one of the causative factors for CC. The HPV prevalence and their genotype distribution among women population are essential to evaluate the deteriorating impact of HPV. A cross-sectional study was performed involving 212 participants to identify the prevalence of high-risk HPV genotypes in south India using PCR and DNA Sequencing. The results obtained from cross-sectional study were used to conduct a meta-analysis of the previous published studies on HPV prevalence and genotype distribution across six geographical regions (North, Northeast, East, Central, West, and South) of India. Additionally, molecular simulation was performed using GROMACS software to determine the structural differences of E6 oncoprotein in HPV-16 and 18 genotypes, characterized from Indian subjects. Among the study participants, the HPV prevalence was found to be 81.70% in CC, 71.42% in HSIL and 61.30% in LSIL. The meta-analysis showed a high prevalence of HPV-16 in CC across the entire six regions. Of which, South and North India were found to have high HPV prevalence among Indian regions. Further, simulation of E6 oncoprotein revealed structural differences between HPV-16 and 18 which may be associated with their oncogenic nature. The HPV-16 and 18 were noticed to be highly prevalent in Indian women. Health awareness and vaccination programs are regularly needed to protect Indian women community. Highlights • Cervical cancer is one of the common gynecologic malignancy in India. • First national based HPV prevalence was estimated across Indian geographic regions. • Our findings contribute with evidence on the burden of HPV in south and north India. • MD simulation showed structural variation between E6 protein of HPV strains. • HPV screening and vaccination are highly needed to prevent Indian women from cancer. [ABSTRACT FROM AUTHOR]

This study presents a remote sensing and geographic information systems-based approach for using US EPA’s Storm Water Management Model (SWMM) in urban environment. Cartosat-1 PAN + IRS-P6 LISS-IV merged product was used to map land cover in part of Surat city at 1:10,000 scale. Cartosat-1 stereo pair was used for deriving digital elevation model of the study area. Geo-informatics-based methods were developed for delineation of sub-catchment areas, assignment of sub-catchment outlets and estimation of characteristic width. It was observed that 59% of the developed area in the study region was directly or indirectly connected to the storm water drainage network. Furthermore, dynamic rainfall-runoff simulation on three-day rainfall indicated that the average runoff coefficient on the urbanized sub-catchment areas which were directly connected to the drainage network was 0.92 as against 0.88 on those urbanized sub-catchments without having direct access to storm water drainage. [ABSTRACT FROM PUBLISHER]