163 research outputs found

    DeepFuse: A Deep Unsupervised Approach for Exposure Fusion with Extreme Exposure Image Pairs

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    We present a novel deep learning architecture for fusing static multi-exposure images. Current multi-exposure fusion (MEF) approaches use hand-crafted features to fuse input sequence. However, the weak hand-crafted representations are not robust to varying input conditions. Moreover, they perform poorly for extreme exposure image pairs. Thus, it is highly desirable to have a method that is robust to varying input conditions and capable of handling extreme exposure without artifacts. Deep representations have known to be robust to input conditions and have shown phenomenal performance in a supervised setting. However, the stumbling block in using deep learning for MEF was the lack of sufficient training data and an oracle to provide the ground-truth for supervision. To address the above issues, we have gathered a large dataset of multi-exposure image stacks for training and to circumvent the need for ground truth images, we propose an unsupervised deep learning framework for MEF utilizing a no-reference quality metric as loss function. The proposed approach uses a novel CNN architecture trained to learn the fusion operation without reference ground truth image. The model fuses a set of common low level features extracted from each image to generate artifact-free perceptually pleasing results. We perform extensive quantitative and qualitative evaluation and show that the proposed technique outperforms existing state-of-the-art approaches for a variety of natural images.Comment: ICCV 201

    A rare case of patellar fracture with quadriceps tendon rupture

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    Quadriceps tendon rupture is the rarest injury with an incidence of 1.37/1,00,000/year. A patellar fracture is the most common injury associated with extensor mechanism lag, but it is rarely found to have quadriceps rupture rather than patellar tendon rupture. Normally when patella fracture occurs the force is disseminated at the bone level rather than at the muscular level. In this case, the force has disseminated at both muscle and bone leading to fracture of patella and quadriceps tendon rupture. Here we report a case of patellar fracture along with quadriceps tendon rupture

    SIMULTANEOUS ESTIMATION OF RELATED COMPOUNDS IN ESOMEPRAZOLE AND NAPROXEN TABLETS BY USING ION PAIR REVERSE PHASE HPLC

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    Objective: To develop and validate a novel gradient reverse phase HPLC method for quantitative estimation of Naproxen and Esomeprazole impurities in pharmaceutical dosage form.Methods: Chromatographic separation was achieved on X-Bridge C18,150x4.6 mm, 3.5 µm column. Detection wavelength was set at 302 nm. The mobile phase A consists of Buffer and Acetonitrile in the ratio of 90:10, where Buffer was prepared by dissolving di ammonium hydrogen phosphate (2.64 gm per Liter) and 1-hexane sulphonic acid sodium salt (1.0 gm per Liter), pH adjusted to 6.5±0.05 with orthophosphoric acid. A mixture of acetonitrile and 1-propanol in the ratio of 90:10 was used as mobile phase B. Flow rate was set to 0.7 mL/minute in gradient elution mode, with a retention time for Naproxen and Esomeprazole 29 and 46 minute respectively.Results: The calibration curve was linear over the concentration range of 4.621 µg/mL – 99.026 µg/mL for Naproxen and 0.254 µg/mL–3.806 µg/mL for Esomeprazole (r= 0.999). The proposed method was found to be (considered)accurate and precise and linear within the desired range. The limit of quantitation (LOQ) was calculated. The purity angle was found less than purity threshold for forced degradation peaks, which shows there was no interference from the common excipient, known impurities and degradents indicating separation, accuracy and reliability of the method. The method was validated as per ICH guidelines and found to be specific, accurate, linear, precise and stability indicating.Conclusion: A Novel, simple, selective and rapid reversed phase high performance liquid chromatographic (HPLC) method was developed and validated for the estimation of Naproxen and Esomeprazole impurities in pharmaceutical dosage form. Hence, the method can be used for routine analysis in various pharmaceutical industries.Â

    Few-Shot Domain Adaptation for Low Light RAW Image Enhancement

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    Enhancing practical low light raw images is a difficult task due to severe noise and color distortions from short exposure time and limited illumination. Despite the success of existing Convolutional Neural Network (CNN) based methods, their performance is not adaptable to different camera domains. In addition, such methods also require large datasets with short-exposure and corresponding long-exposure ground truth raw images for each camera domain, which is tedious to compile. To address this issue, we present a novel few-shot domain adaptation method to utilize the existing source camera labeled data with few labeled samples from the target camera to improve the target domain's enhancement quality in extreme low-light imaging. Our experiments show that only ten or fewer labeled samples from the target camera domain are sufficient to achieve similar or better enhancement performance than training a model with a large labeled target camera dataset. To support research in this direction, we also present a new low-light raw image dataset captured with a Nikon camera, comprising short-exposure and their corresponding long-exposure ground truth images.Comment: BMVC 2021 Best Student Paper Award (Runner-Up). Project Page: https://val.cds.iisc.ac.in/HDR/BMVC21/index.htm

    Schwannoma arising from hypoglossal nerve in the submandibular triangle: a case report

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    Hypoglossal schwannomas usually develop in the intracranial portion of the brain. The incidence of hypoglossal schwannomas of the submandibular region is extremely rare. Here we report a case of schwannoma arising from the extracranial hypoglossal nerve in the left submandibular region

    Enantioselective Synthesis of Antiepileptic Drug: (-)-Levetiracetam-Synthetic Applications of the Versatile New Chiral N-Sul�nimine

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    We report an asymmetric synthesis of (-)-Levetiracetam (1) in six steps starting from versatile new chiral N-sul�nimine (3). e key step, stereoselective 1,2-addition of ethylmagnesium bromide (EtMgBr) to chiral N-sul�nimine derived from (R)-glyceraldehyde acetonide and (S)-t-BSA, gave the corresponding sulfonamide (2) in high diastereoselectivity. Simultaneous deprotection and deacetylation followed by NaIO 4 cleavage and reduction gave -amino alcohol (6). Subsequent reactions yielded the targeted compound levetiracetam (1)

    Characterization of phoA, a Bacterial Alkaline Phosphatase for Phi Use Efficiency in Rice Plant

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    Fertilizers and herbicides are two major components in the agriculture system for achieving crop productivity. Massive use of orthophosphate fertilizers and herbicides poses threats to phosphate reserves and aids the evolution of herbicide tolerant weed biotypes. Phosphite (Phi), a phosphate analog, has been proposed as more beneficial than traditionally used phosphate fertilizers and herbicides in the agriculture. We developed phoA overexpressing transgenic rice that minimizes the phosphate loss and contributes to weed management in the agriculture. The phoA rice lines showed improved root, shoot length and total biomass production under phosphite conditions. Additionally, the complete phenotype and productivity of phoA lines under the phosphite treatment attained was similar to that of plants under phosphate sufficient condition. The Phi metabolizing properties of the phoA overexpressed lines improved under the Phi application and phi treatment enabled controlling of weeds without compromising the yield of transgenic rice plants. Our results indicated that phoA alone or in combination with other Phi metabolizing gene(s) can possibly be used as an effective ameliorating system for improving crop plants for phi-based fertilization and weed management strategy in the agriculture

    The combined effects of electrojet strength and the geomagnetic activity (<I>K<sub>p</sub></I>-index) on the post sunset height rise of the F-layer and its role in the generation of ESF during high and low solar activity periods

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    International audienceSeveral investigations have been carried out to identify the factors that are responsible for the day-to-day variability in the occurrence of equatorial spread-F (ESF). But the precise forecasting of ESF on a day-to-day basis is still far from reality. The nonlinear development and the sustenance of ESF/plasma bubbles is decided by the background ionospheric conditions, such as the base height of the F-layer (h'F), the electron density gradient (dN/dz), maximum ionization density (Nmax), geomagnetic activity and the neutral dynamics. There is increasing evidence in the literature during the recent past that shows a well developed Equatorial Ionization Anomaly (EIA) during the afternoon hours contributes significantly to the initiation of ESF during the post-sunset hours. Also, there exists a good correlation between the Equatorial Ionization Anomaly (EIA) and the Integrated Equatorial ElectroJet (IEEJ) strength, as the driving force for both is the same, namely, the zonal electric field at the equator. In this paper, we present a linear relationship that exists between the daytime integrated equatorial electrojet (IEEJ) strength and the maximum elevated height of the F-layer during post-sunset hours (denoted as peak h'F). An inverse relationship that exists between the 6-h average Kp-index prior to the local sunset and the peak h'F of the F-layer is also presented. A systematic study on the combined effects of the IEEJ and the average Kp-index on the post-sunset, peak height of the F-layer (peak h'F), which controls the development of ESF/plasma bubbles, is carried out using the ionosonde data from an equatorial station, Trivandrum (8.47° N, 76.91° E, dip.lat. 0.5° N), an off-equatorial station, SHAR (13.6° N, 79.8° E, dip.lat. 10.8° N) and VHF scintillations (244 MHz) observed over a nearby low-latitude station, Waltair (17.7° N, 83.3° E, dip.lat. 20° N). From this study, it has been found that the threshold base height of the F-layer at the equator for the development of plasma bubbles is reduced from 405 km to 317 km as the solar activity decreases from March 2001 (mean Rz=113.5) to March 2005 (mean Rz=24.5). This decrease in threshold height with the decreasing solar activity is explained on the basis of changes in the local linear growth rate of the collisional Rayleigh-Taylor instability, due to the variability of various terms such as inverse density gradient scale length (L?1), ion-neutral collision frequency (?in) and recombination rate (R) with the changes in the solar activity
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