Niraparib is an oral poly(adenosine diphosphate ADP-ribose) polymerase (PARP) 1/2 inhibitor that has shown clinical activity in patients with ovarian cancer. We sought to evaluate the efficacy of ...niraparib versus placebo as maintenance treatment for patients with platinum-sensitive, recurrent ovarian cancer.
In this randomized, double-blind, phase 3 trial, patients were categorized according to the presence or absence of a germline BRCA mutation (gBRCA cohort and non-gBRCA cohort) and the type of non-gBRCA mutation and were randomly assigned in a 2:1 ratio to receive niraparib (300 mg) or placebo once daily. The primary end point was progression-free survival.
Of 553 enrolled patients, 203 were in the gBRCA cohort (with 138 assigned to niraparib and 65 to placebo), and 350 patients were in the non-gBRCA cohort (with 234 assigned to niraparib and 116 to placebo). Patients in the niraparib group had a significantly longer median duration of progression-free survival than did those in the placebo group, including 21.0 vs. 5.5 months in the gBRCA cohort (hazard ratio, 0.27; 95% confidence interval CI, 0.17 to 0.41), as compared with 12.9 months vs. 3.8 months in the non-gBRCA cohort for patients who had tumors with homologous recombination deficiency (HRD) (hazard ratio, 0.38; 95% CI, 0.24 to 0.59) and 9.3 months vs. 3.9 months in the overall non-gBRCA cohort (hazard ratio, 0.45; 95% CI, 0.34 to 0.61; P<0.001 for all three comparisons). The most common grade 3 or 4 adverse events that were reported in the niraparib group were thrombocytopenia (in 33.8%), anemia (in 25.3%), and neutropenia (in 19.6%), which were managed with dose modifications.
Among patients with platinum-sensitive, recurrent ovarian cancer, the median duration of progression-free survival was significantly longer among those receiving niraparib than among those receiving placebo, regardless of the presence or absence of gBRCA mutations or HRD status, with moderate bone marrow toxicity. (Funded by Tesaro; ClinicalTrials.gov number, NCT01847274 .).
Spectral unmixing is one of the unique advantages of hyperspectral images to map the type of species. Such images contain a high spectral resolution making it a classical problem of signal processing ...at each pixel, which is supposedly formed by the interaction of variously constituted end-members (also known as mixed pixels). Finding the abundance of any feature (or class or end-member) may require these mixed pixels to be unmixed through mixing models. This study proposes a linear mixing model and a non-linear mixing model combined for spectral unmixing and suggests a modified mixing model. We proposed linearly unmixed abundances to be used as prior probabilities for non-linear mixing models. We have applied these methods to synthetic data to check performance and robustness. Synthetic data was created using the reflectance spectra of various end-members collected in the study region through rigorous field surveys. Abundance accuracy, reconstruction accuracy, and other statistical measures were used to assess overall accuracy, with results showing that Modified PPNMM performs better than PPNMM and LMM. The performance outcome is further validated with a satellite dataset (hyperspectral data of Hyperion) with randomly distributed points.
Polarimetric Synthetic Aperture Radar (PolSAR) calibration is an essential preprocessing step that must be performed to ensure that the data quality is adequate. This, in turn, helps to minimize the ...propagation of errors in any further data processing or information extraction. Crosstalk and channel imbalance are two major distortions found to be present in the uncalibrated polarimetric SAR data. The PolSAR calibration mainly aims to reduce these two distortions revealing the true scattering pattern of the targets. In this regard, Quegan's algorithm and Ainsworth algorithm are two widely used algorithms for the PolSAR calibration. In this study, the accuracy and efficiency of these two algorithms have been thoroughly compared using suitable metrics. It has been shown that the Ainsworth algorithm performs better than Quegan's in terms of accuracy at the cost of poor computational efficiency. The data quality metrics also highlight the better calibration accuracy of the Ainsworth algorithm. The issue of higher computational complexity has been effectively addressed by coupling both of these algorithms. Evidently, the computational cost has been reduced in the case of the proposed algorithm. The polarization orientation angle (POA) shift is another distortion caused by the topographic variations present in the target scene. Therefore, correction of POA shift has been incorporated in this research by coupling it with the PolSAR calibration. Subsequently, the improvement in the scattering has been observed. In essence, the proposed algorithm coupled with the correction of POA shift rectifies the major polarimetric distortions with adequate accuracy and computational efficiency.
Key Points
A computationally efficient algorithm for Polarimetric Synthetic Aperture Radar (PolSAR) calibration
Estimation and comparison of PolSAR data quality before and after the calibration
Comparison of existing PolSAR calibration algorithms
Cultural heritage is susceptible to damages caused by natural hazards and other factors, and it is difficult to guarantee their eternality. A vital aspect of heritage conservation is the knowledge ...about the presence of damages threatening the stability of the structure. Traditional methods of crack identification involve visual inspection and measurements, which may be time-consuming and are invasive in nature. This may result in considerable risk to the structural health of the monument. Also, manual mapping of these damages is expensive and time-consuming. The use of geospatial technologies in documenting the damages in the built heritage could be significant. The current study focuses on using high-resolution range and intensity data processed via advanced imaged processing and 3D modelling techniques to document and detect damages automatically in the built heritage. Ultra-high-density laser scans along with images are used for the detection of cracks and damages in the structure. The concept of fractal analysis is used for the identification and subsequent reconstruction of broken patterns. The results have been validated by comparing them to reference data. Accuracy metrics like correctness and completeness are computed. A correctness value of 0.90 and completeness of 0.65 was achieved for the identification of damage. A correspondence of 93% was obtained while comparing a virtually reconstructed pattern with the undamaged pattern in reference. The experimental results indicate that the methodology is effective for damage detection and virtual reconstruction in built heritage. The technique can serve as an efficient method for documenting damages in complex structures and elaborate patterns.
Distance learning is the process of creating an educational experience of equal qualitative value for the learner to best suit their needs outside the classroom. Distance Learning Program (DLP) ...offered by Indian Institute of Remote Sensing (IIRS), Indian Space Research Organisation (ISRO), has witnessed steady growth in the last thirteen years benefitted more than
2.65 lakh
participants from
2650
network institutes distributed across the country. Under this program, IIRS has successfully established a network of academic and professional Institutions in the country. The Covid-19 pandemic has affected higher education severely. India was under complete lockdown during April and May 2020. In this scenario, to ensure uninterrupted and safe access to learning, IIRS has responded to the crisis by tapping into its existing DLP. During the lockdown and post-lockdown period, IIRS conducted 11 Live and Interactive course/workshop/webinars focusing on Basics and Advanced topics related to Geospatial technology. During this period, IIRS DLP witnessed an exponential growth in terms of number of participation, number of participating institutes and also the percentage of working professionals. IIRS DLP witnessed a fivefold growth in participation benefitting around 57,000 participants from across the country. The number of network institutes also grew by 50% during April–June 2020. Statistics indicate that during January–June IIRS outreach program witnessed 22-fold growth in number of professionals joining the courses. Also, the overall feedback of the course by participants was very encouraging. Even though there are times when nothing can replace the personal attention of a teacher, in the current situation the focus is on utilizing technology effectively for uninterrupted learning.
Abstract
Warming-induced expansion in vegetation coverage and activity can accelerate the montane hydrological regimes. However, the climate impacts on ecohydrology of forested valleys of the ...Himalaya are uncertain. In this study, utilizing results of about three centuries of cellulose isotope chronologies (
δ
13
C and
δ
18
O) of dominant tree species, geo-chronological proxies, bio-geophysical dataset and simulations including satellite observations, we show an activation in the ecophysiological processes including evapotranspiration (ET) since the 1950s. Observation suggests rapid greening, while isotopic records indicate enhanced assimilation and transpiration in deciduous species vis-à-vis conifers post 1950s. Given strong vegetation-precipitation feedback and superimposed on the increasing trends of conducive atmospheric factors affecting valley-scale convective processes, intensification in forest ET is manifesting in a progressive enhancement in extreme rainfall events (EREs) since the last few decades. Results suggest that representation of ecophysiological processes and dynamics of seasonal moisture loading in observational and modelling framework is critical for understanding EREs under climate change.
Complex regional pain syndrome (CRPS) is a poorly understood pain disorder with little information on the natural course of the disease. Changes in its diagnostic criteria have simplified the ...identification of this syndrome, but convincing epidemiological data regarding this disorder are still lacking. Here, we collected epidemiological and other relevant information regarding CRPS via a Web-based survey to develop a better understanding of the epidemiology, symptoms, progression, therapy, and associated psychosocial factors related to CRPS.
A survey of 75 questions was hosted on the Web site of the Reflex Sympathetic Dystrophy Syndrome Association of America for 5 months. One thousand three hundred fifty-nine subjects responded, and 888 of these satisfied the inclusion criteria for CRPS and were accepted for data analysis.
Complex regional pain syndrome affected mostly white women in the 25- to 55-year-old age group. It was often precipitated by trauma (surgical or nonsurgical) and commonly involved the lower ( approximately 56%) and upper ( approximately 38%) extremities. Pain was usually accompanied by edema, vasomotor, sudomotor, motor, and trophic changes. The syndrome commonly progressed and spread to involve other body areas. Affected patients failed multiple pharmacological and nonpharmacological interventions. The syndrome frequently interfered with job ( approximately 62% disability rate), sleep ( approximately 96%), mobility ( approximately 86%), and self-care ( approximately 57%). Remissions and relapses were both common.
Complex regional pain syndrome is a severe disabling pain disorder that results in physical as well as emotional and financial consequences to patients. The disease complexity requires coordination of multidisciplinary care that can be achieved by educational efforts directed to general practitioners.
Vertical striping are quite common in Hyperion images. The removal of these stripes turns out to be an important step of noise correction along with atmospheric and other artifact correction. Often ...these corrections are applied on radiometric values in spatial domain or fequency domain. We have proposed a novel approach to correct these vertical stripes using wavelet transformation and singular value decomposition. In the first step, we proposed stripe identification based on the Eigen ratio of first and second Eigen values of vertical components (decomposed using wavelet transformation). This ratio is supposed to be very high for striped images and minimal for stripe free images. This is because of the contribution to first Eigen value of high frequency stripes. These high frequency stripes contributes tremendously to the first Eigen because of their dominance in vertical component. We have also proposed a threshold function to identify the bands that needs to be corrected. After the stripes identification and correction algorithm is appllied on respective bands, it is observed that proposed method successfully removed striping noise with high accuracy. Upon comparing the results of proposed method with various other methods, it is found that proposed method have an edge and performing better than rest of the methods. To assess the results, SNR value was calculated for all methods and found highest for the proposed method except Local Threshold approach. Local Threshold have better SNR probably because of intact noise (even in visual inspection but also present in frequency plot of vertical wavelet component) in these methods.
Abstract Persistent postmastectomy pain is quite common and has been classified into several distinct types. Few studies, however, have investigated either the predictors or functional impact of ...multiple types of post mastectomy pain. In this investigation, 278 women, who were, on average, several years post mastectomy, completed questionnaires assessing pain, pain-related physical function, and psychosocial distress. We assessed three distinct categories of postmastectomy pain: phantom breast pain, scar pain, and other mastectomy-related pain. Each of the three types of postmastectomy pain was strongly related to one another (i.e., women reporting one type of pain were more likely to report the other types as well). In general, the more types of postmastectomy pain a woman reported, the greater the degree of disability and distress. Collectively, the presence of “other mastectomy-related pain” was a stronger unique predictor of disability and distress than were the other two categories of pain. Interestingly, demographic and surgical factors, including time since surgery, were not consistent predictors of pain or function. The findings suggest that the assessment of postmastectomy pain should include formal evaluation of multiple types of pain, with additional attention paid to the category of “other mastectomy-related pains,” and that the number of types of pain reported by women after surgery may be important in predicting functional outcomes.
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