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River regulation by dams and embankments drastically reduce/alter flow, which affects the natural channel pattern. Existing braiding indices have seldom incorporated the effects of diurnal flow variations caused by hydropeaking, leading to over/underestimation of the braiding intensity. These indices consider only the visible wet channels, ignoring the existence of dry channels that are activated only episodically during phases of water release from hydropower dams. We have extracted the dry channels (those that are periodically wet) coursing across the channel belt of the highly regulated River Tista from Landsat images between 1977 and 2014, using Normalized Difference Wetness Index values. These were combined with existing wet channel widths and numbers to formulate the Regulated Braiding Index (RBi) for characterizing channel braiding in the Tista's course over the Himalayan foothill plains. Overall, the widths and numbers of wet channels decreased by 63% and 25%, respectively, during the regulated years (2003 and 2014) as compared to pre‐dam years (1977 and 1995) due to the collective operation of 14 upstream dams/barrages (having cumulative ~89 million m3 reservoir capacity), whose operations reduced the braiding intensity (eliciting lower RBi values). Further, the number of high braiding reaches decreased by half while low braiding stretches rose by 10% in comparison to the pre‐dam period due to reduced/regulated flow. Comparative analysis of derived RBi values with three existing braiding indices revealed that RBi values consistently decreased near barrages, bridges, and within embankment‐confined reaches, unlike the other indices, thus providing a better framework for assessing expected river regulation effects. [ABSTRACT FROM AUTHOR]

Premise of research. Polypodiaceae, the largest leptosporangiate fern family, is distributed mainly in the tropical and subtropical regions of India, China, New Zealand, and Malaysia. This family has a rich macrofossil record in the Cenozoic sediments of China, but no macrofossil of Polypodiaceae has been reported from the Cenozoic sediments of India to date. Here, we report for the first time the occurrence of fossil frond remains resembling morphologically those of the extant microsoroid wart fern genus Microsorum Link from the late Miocene Siwalik sediments exposed around Sarkaghat, Mandi district of Himachal Pradesh, Western Himalaya, India. Methodology. The present frond fossils were revealed by careful removal of the overlying matrix and studied under light compound, stereo zoom, and inverted fluorescence microscopes. They are identified based on their detailed morphological (macro and micro) features and through the comparison with other modern Polypodiaceae genera as well as with earlier reported polypodiceous fern fossil species. Pivotal results. The fossil frond specimens are described here as a new species, namely, Palaeosorum siwalikum Kundu, Hazra et Khan sp. nov. The new Siwalik vascular cryptogam species is characterized by leaf shape (simple frond with entire margin), venation pattern (brochidodromous nature of secondary veins, tertiary and quaternary veins reticulate, anastomosing and forming a row of irregular or quadrangular-shaped areoles between two lateral secondary veins), and presence of free included veinlets (unbranched or forked, ending with club-shaped hydathodes). Conclusions. These new fossil materials confirm the existence of a Microsorum -like plant in the Siwalik Miocene forests of Himachal Pradesh. We review in detail the fossil record and highlight the phytogeographic history of Polypodiaceae. In addition, we also suggest probable migratory routes for this fern family. [ABSTRACT FROM AUTHOR]

The Ventilago Gaertn. (Rhamnaceae) is widely distributed in pantropical areas of Africa, Asia, and Australia. However, fossil records of this taxon are sparse, which limits understanding of the evolution and biogeographic history of the genus. In the present study, we report and describe two new fossil species of Ventilago, V. siwalika sp. nov. from the Miocene sediments of Himachal Pradesh, western Himalaya, and V. pliocenica sp. nov. from the Pliocene sediments of Jharkhand, eastern India based on single‐winged samaras. Ventilago pliocenica is characterized by a prominent midvein, obtuse to sub‐round apex with mucronate tip, longitudinal secondary veins extending the full length of the fruit, and reticulate nature of higher‐order veins, the presence of equatorial rim, the hypanthium, and short pedicel. On the other hand, V. siwalika is characterized by a prominent midvein, obtuse to sub‐round apex with mucronate tip, longitudinal secondary veins extending the full length of the fruit, and reticulate nature of higher‐order veins. Our discovery represents the first unambiguous fossil record of single‐winged samara of Ventilago from India and provides valuable insights into the evolution of this genus. In this paper, we also review its biogeographic history and add new information to understand its hypothetical migration route. Present and earlier records of Ventilago also suggest that this genus was a common forest element during Neogene (Miocene time) in Asia. [ABSTRACT FROM AUTHOR]

This paper proposes an energy efficient approach for securing inter-connecting IOT devices with servers. A scheme using blockchain and a second network for security management was previously described [1]. To overcome the drawbacks and shortcomings of using traditional smart contract with Ethereum, a new approach is proposed. The proposed approach ensures that the overall IoT network is "hardened" against attack using a framework which is environmentally sustainable and meets the stringent requirements of mission critical applications. This new approach also results in shorter latency, higher throughput and consuming less power, thus suitable for edge computing environment in mobile. [ABSTRACT FROM AUTHOR]

The coal-bearing Barakar succession of the Satpura basin is typical of the Gondwanan coal basins of peninsular India, in that it has previously been interpreted as continental in origin. The succession comprises three main facies associations, which are documented within this paper. Medium- to fine-grained muddy sandstone deposits of 5-75 m thickness are reinterpreted as tidally influenced delta deposits. Mudstone deposits of 3-20 m thickness with subordinate sandstones, coals and carbonaceous shales are reinterpreted as delta top deposits, and medium to coarse sandstones of 3-38 m thickness are interpreted as braided delta-top channels. The evidence for tidal influence arises from documentation of bidirectional cross-strata, tidal bundles, tidal rhythmites and periodic variation in foreset thickness. The recognition of tidal deposits indicates marine depositional conditions and significantly changes existing palaeogeographical models. This in turn has important implications for our understanding of the depositional setting and distribution of the Permian coals that occur across much of the southern supercontinent. Furthermore, to the best of the authors' knowledge, coal-bearing tidal-delta deposits have not previously been described from continental interior basins. Keywords: Gondwana, coal, hummocky cross-stratification, deltaic sedimentation, intertidal sedimentation.