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A moderate size earthquake (ML 5.9) occurred near Mechuka in Siang Valley on 23rd April 2019 at 20:15:50.00 UTC in the rupture zone of the great Assam earthquake of 15th August 1950. This shallow-focused earthquake occurred close to NE trending Main Central Thrust has a thrust fault mechanism striking parallel to this major tectonics of the Himalaya. Including this event, a dataset of 46 local, micro and low magnitude earthquakes (1.5 ≤ ML ≤ 5.9) of the Siang Valley of Arunachal Pradesh, NE India, are evaluated for the characteristics of the earthquake source, seismicity, stress drop and tectonic structures. The earthquake events were recorded by a close digital network of eight broadband seismic stations installed in December 2018 in the Siang Valley. The stress drop (Δσ) obtained for the Mechuka earthquake in the Siang Valley is 114.71 bars, the seismic moment (Mo) of 6.86E + 16 Nm and the source radius (r) of 1392.41 m. The seismic moments obtained from the microearthquakes vary between 2.44E + 11 and 6.86E + 16 Nm, and the source radius varies from 172.90 to 1392.41 m based on Brune's circular source model 1970. The corner frequencies (fc) of the events range from 1.03 to 8.04 Hz. Seismically intense clustering of microearthquakes has a low-stress drop below 10 bar except for the Mechuka earthquake, which varies from 0.05 to 114.72. This high-stress drop of moderate earthquake compared to its low values of lower magnitude earthquakes indicates that the earthquake of 23rd April 2019 is associated with high-strength material accumulating high strain during the earthquake-building process. Moment magnitude of whole data set ranges from 1.52 to 5.16. The scaling relationship between Mo and fc is obtained as 9.089E + 16fc–9.52, and for Mo and Δσ are modelled to be related as Mo = 8.96E + 10Δσ2.86. Evaluated low-stress drop for the smaller size of earthquakes shows brittleness of the upper crustal region. Research highlights: Modelling of earthquake source parameters to obtain scaling relations for Siang Valley, Arunachal Pradesh. The estimated Mo, fc, r, ∆σ and Mw are 2.44 × 1011 to 6.86 × 1016 Nm, 1.03–8.04 Hz, 172.90–1392.41 m, 0.05–114.71 bar and 1.52–5.16, respectively. Scaling relation between Mo and fc, Mo and Δσ and Mw and fc is Mo = 9.089E + 16fc−9.52, Mo = 8.96E + 10 Δσ2.86 and Log fc = –0.39Mw + 2.39, respectively. [ABSTRACT FROM AUTHOR]

Backlit image enhancement is a challenging research problem in image processing and computer vision. The complexity of enhancing backlit images is that they simultaneously contain bright and dark intensity regions. Existing state-of-the-art methods usually have low contrast enhancement in the dark regions, are prone to color distortion in the background or noise amplification, and have high computational complexity. Inspired by its potentiality, this paper applies region segmentation and a transfer learning-based approach to enhance the contrast of the dark regions in backlit images using multi-illumination mappings. In the proposed framework, gamma and log transform functions are applied to achieve a varied set of illumination-map to improve the brightness and contrast of the backlit image. The average results of the validation metrics of the proposed method for contrast measure (CM), entropy (E), CM/E ratio, and SSIM are 8.10, 7.52, 1.07, and 0.58, respectively. The experimental results corroborate that the proposed method demonstrates superior performance to state-of-the-art methods both subjectively and objectively. [ABSTRACT FROM AUTHOR]

Cellular metabolism plays an essential role in the regrowth and regeneration of a neuron following physical injury. Yet, our knowledge of the specific metabolic pathways that are beneficial to neuron regeneration remains sparse. Previously, we have shown that modulation of O-linked β-N-acetylglucosamine (O-GlcNAc) signaling, a ubiquitous post-translational modification that acts as a cellular nutrient sensor, can significantly enhance in vivo neuron regeneration. Here, we define the specific metabolic pathway by which O-GlcNAc transferase (ogt-1) loss of function mediates increased regenerative outgrowth. Performing in vivo laser axotomy and measuring subsequent regeneration of individual neurons in C. elegans, we find that glycolysis, serine synthesis pathway (SSP), one-carbon metabolism (OCM), and the downstream transsulfuration metabolic pathway (TSP) are all essential in this process. The regenerative effects of ogt-1 mutation are abrogated by genetic and/or pharmacological disruption of OCM and the SSP linking OCM to glycolysis. Testing downstream branches of this pathway, we find that enhanced regeneration is dependent only on the vitamin B12 independent shunt pathway. These results are further supported by RNA sequencing that reveals dramatic transcriptional changes by the ogt-1 mutation, in the genes involved in glycolysis, OCM, TSP, and ATP metabolism. Strikingly, the beneficial effects of the ogt-1 mutation can be recapitulated by simple metabolic supplementation of the OCM metabolite methionine in wild-type animals. Taken together, these data unearth the metabolic pathways involved in the increased regenerative capacity of a damaged neuron in ogt-1 animals and highlight the therapeutic possibilities of OCM and its related pathways in the treatment of neuronal injury. [ABSTRACT FROM AUTHOR]

The Siang Valley of Arunachal Pradesh, North-East India, is one of the seismotectonically active region that lie in the eastern Himalayan Syntaxis (EHS); we have investigated seismicity, fault plane solutions (FPS) and P (Pressure) axis orientation in this region. We have analyzed 756 local earthquakes of magnitude range (1.0 ≤ ML ≤ 5.9) in the region during the period from January 2019 to December 2021. From the spatial distribution of local seismicity, it is estimated that the concentration of seismicity is in Namcha-Barwa, western and eastern flanks of Siang Antiform, respectively. The depth distribution of seismicity extends upto a focal depth of 60 km with a higher concentration in the upper crustal part. Further, we determined 15 fault plane solutions (FPS) using waveform inversions (ISOLA) for events with a magnitude range of 3.5 to 5.9. The waveform inversion has been performed for the events with maximum azimuthal coverage. The frequency band used for the inversion is in the 0.01–0.1 Hz range corresponding to the maximum signal to noise ratio to precise crustal velocity structures, hypocenter positions, and appropriate frequency ranges were used to obtain reliable FPS. The FPS obtained for the shallow focused earthquakes shows Normal faulting with Strike-slip components. The compressional axes orientations of the thrust FPS show a north-east direction. The intense seismic activity and compressional axis orientation in this study area is due to the collision between Indian and Eurasian plate in the north and and east-ward subduction of Indian plate below the Burmese plate. [ABSTRACT FROM AUTHOR]

The cause–effect relationship has tremendous role in interpreting the engineering and scientific problems which basically deals with the identifying potential causes of problem. Bayesian belief networks (BBN) also referred as Bayesian casual probabilistic network used widely to deal with probabilistic events to elucidate the complications having uncertainty. A major challenge in BBN is to construct a node probability table (NPT), which grows exponentially with the rising number of variables. Various approaches exist for NPT construction, including expert elicitation, data analysis, survey and weighted functions, noisy-OR, noisy-MAX, recursive noisy-OR (ROR), extended recursive noisy-OR, and ranked nodes. However, these methods are problem-specific and lacking behind a generalized approach applicable to all problem types. To address this issue, this paper proposes a generalized universal approach for constructing the NPT using fuzzy logic. The suggested strategy has been validated by applying it to a BBN prototype for software design and development. The proposed strategy has been evaluated with best-case and worst-case software metrics. [ABSTRACT FROM AUTHOR]

We investigated sedimentary thickness and shear wave velocity structure in the western part of the Indo-Gangetic Plain (Punjab and Haryana Plain) and adjoining Siwalik Himalaya with the help of receiver function inversion at 20 broad-band seismological stations. This region is one of the most seismically vulnerable zones of the world due to the presence of thick surface sediments in the foreland basin that can amplify seismic waves and cause huge damage due to the earthquakes of the Himalaya. The study reveals a progressive thickening of sediments from southwest to northeast. The basement depth varies from ∼1.5 to 1.7 km in the Central Alluvium Plain, ∼1.8 to 2.8 km in the Zone of Terminal Fans, and attains a maximum of ∼3.8 km near the Himalayan Frontal Thrust. The inverted models show the presence of soft alluvial with extremely low Vs (< 0.5 km s−1) and high Vp / Vs (∼2.5–3.0) at the top ∼400–700 m of the surface at most of the stations. A comparatively higher velocity of surface sediments observed at northern stations suggests the presence of compact sediments at the surface. The layered sedimentary structure revealed by the S -wave velocity models supports the previous geophysical investigations using borehole data. The velocity–depth structure obtained in this study is important for evaluating the seismic hazard of the densely populated urban areas spread over this region. [ABSTRACT FROM AUTHOR]