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Multilocus phylogeny and a new classification for African, Asian and Indian supple and writhing skinks (Scincidae: Lygosominae)
No full textThe genera Lepidothyris, Lygosoma and Mochlus comprise the writhing or supple skinks, a group of semi-fossorial, elongate-bodied skinks distributed across the Old World Tropics. Due to their generalized morphology and lack of diagnostic characters, species- and Glade-level relationships have long been debated. Recent molecular phylogenetic studies of the group have provided some clarification of species-level relationships, but a number of issues regarding higher level relationships among genera still remain. Here we present a phylogenetic estimate of relationships among species in Lygosoma, Mochlus and Lepidothyris generated by concatenated and species tree analyses of multilocus data using the most extensive taxonomic sampling of the group to date. We also use multivariate statistics to examine species and Glade distributions in morpho space. Our results reject the monophyly of Lygosoma s.l., Lygosoma s.s. and Mochlus, which highlights the instability of the current taxonomic classification of the group. We, therefore, revise the taxonomy of the writhing skinks to better reflect the evolutionary history of Lygosoma s.l. by restricting Lygosoma for Southeast Asia, resurrecting the genus Riopa for a Glade of Indian and Southeast Asian species, expanding the genus Mochlus to include all African species of writhing skinks and describing a new genus in Southeast Asia
Quinoxaline derivatives disrupt the base stacking of hepatitis C virus-internal ribosome entry site RNA: reduce translation and replication
No full textRNA-biased small molecules with a monoquinoxaline core target the L-shaped structure of subdomain IIa of Hepatitis C virus internal ribosome entry site (IRES) RNA in proximity to the Mg2+ binding site. The binding event leads to the destacking of RNA bases, resulting in the inhibition of IRES-mediated translation and HCV RNA replication
Oriented Active Solids
No full textWe present a complete analysis of the linearized dynamics of active solids with uniaxial orientational order, taking into account a hitherto overlooked consequence of rotation invariance. Our predictions include a purely active response of two-dimensional orientationally ordered solids to shear, the possibility of stable active solids with quasi-long-range order in two dimensions and long-range order in three dimensions, generic instability of the solid for one sign of active forcing, and the instability of the uniaxially ordered phase in momentum-conserved systems for large active forcing irrespective of its sign
Search for Physics beyond the Standard Model in Events with Overlapping Photons and Jets
No full textResults are reported from a search for new particles that decay into a photon and two gluons, in events with jets. Novel jet substructure techniques are developed that allow photons to be identified in an environment densely populated with hadrons. The analyzed proton-proton collision data were collected by the CMS experiment at the LHC, in 2016 at root s = 13 TeV, and correspond to an integrated luminosity of 35.9 fb(-1). The spectra of total transverse hadronic energy of candidate events are examined for deviations from the standard model predictions. No statistically significant excess is observed over the expected background. The first cross section limits on new physics processes resulting in such events are set. The results are interpreted as upper limits on the rate of gluino pair production, utilizing a simplified stealth supersymmetry model. The excluded gluino masses extend up to 1.7 TeV, for a neutralino mass of 200 GeV and exceed previous mass constraints set by analyses targeting events with isolated photons
Simultaneous longitudinal and transverse oscillations in filament threads after a failed eruption
No full textContext. Longitudinal and transverse oscillations are frequently observed in the solar prominences and/or filaments. These oscillations are excited by a large-scale shock wave, impulsive flares at one leg of the filament threads, or due to any low coronal eruptions. We report simultaneous longitudinal and transverse oscillations in the filament threads of a quiescent region filament. We observe a large filament in the northwest of the solar disk on July 6, 2017. On July 7, 2017, it starts rising around 13:00 UT. We then observe a failed eruption and subsequently the filament threads start to oscillate around 16:00 UT. Aims. We analyse oscillations in the threads of a filament and utilize seismology techniques to estimate magnetic field strength and length of filament threads. Methods. We placed horizontal and vertical artificial slits on the filament threads to capture the longitudinal and transverse oscillations of the threads. Data from Atmospheric Imaging Assembly onboard Solar Dynamics Observatory were used to detect the oscillations. Results. We find signatures of large-amplitude longitudinal oscillations (LALOs). We also detect damping in LALOs. In one thread of the filament, we observe large-amplitude transverse oscillations (LATOs). Using the pendulum model, we estimate the lower limit of magnetic field strength and radius of curvature from the observed parameter of LALOs. Conclusions. We show the co-existence of two different wave modes in the same filament threads. We estimate magnetic field from LALOs and suggest a possible range of the length of the filament threads using LATOs
Permeability characterization of porouspreform during VARTM using fractals
No full textAccurate characterization of permeability of the complex architecture of porous preform is the first step towards efficient and cost-effective resin impregnation to yield composite parts via vacuum assisted resin transfer molding (VARTM). Determination of preform permeability in different directions is inherently dependent on the available pore spaces in the complex labyrinth of the fabric layup. A major challenge is to understand the pattern of disordered complex microstructure and a quantitative description of permeability as a function of local porosities. Depending on the fiber alignment, several models have been developed to determine permeability as a function of fiber volume fraction by means of flow thorough ordered compacted parallel and perpendicular channels. It was observed that in most cases, experimentally determined permeability fitted well with the classical permeability porosity relation of Kozeny-Carman (KC) model with an empirical Kozeny constant as a fitting estimate. KC model shows that as the fiber volume fraction decreases the permeability increases; however, results indicate that in some cases, this behavior is not exhibited. Detailed permeability experiments conducted on carbon fiber preform YC200 (Fibertech Co. Ltd.) show that as the fiber volume fraction increases, the permeability along the fiber direction increases; the converse was found to occur for permeability experiments conducted on the fabric in the transverse direction. Once the fiber layups are stacked together, diameter of micro pores and capillary channels do not behave like perfectly aligned parallel micro channels. There is considerable disorder in the preform microstructure in terms of different capillary diameters, length of the tortuous capillaries between tows, spacing between individual filaments within a single tow, and the spacing between stitching threads of the fabric, etc. In the present study, two separate unit cell models have been developed with and without a combination of pore area fractal dimension and tortuosity. Predicted results a good agreement with the experimentally determined permeability in both the longitudinal and transverse directions
First observation of microspherule from the infratrappean Gondwana sediments below Killari region of Deccan LIP, Maharashtra (India) and possible implications
No full textA rare occurrence of a microspherule has been found in the infratrappean sediments, encountered below 338 m thick Deccan volcanic cover in KLR-1 scientific borehole, drilled in the epicentral zone of the 1993 Killari earthquake (Maharashtra, India). Palynological studies of the sediments indicate their age as Early Permian (Asselian, 298-295 Ma) for deposition. Transmission electron microscope studies reveal that the spherule from the infratrappeans, is having a similar composition to that of the Neoarchean amphibolite to granulite facies mid crustal basement. The spherule is non-spherical in nature, containing mostly FeO (10.70 +/- 0.20 wt.%), CaO (13.8 +/- 0.5 wt.%), Al2O3 (7.78 +/- 0.30 wt.%), MgO (6.47 +/- 0.3 wt.%), SiO2 (47.46 +/- 0.50 wt.%), TiO2 (2.47 +/- 0.3 wt.%), K2O (1.89 +/- 0.20 wt.%), and Cl (0.33 +/- 0.05 wt.%). Since the Fe composition of the spherule is almost same as the basement rock (10.5 wt.%), and the chlorine content is also in the same range as the basement (0.04-0.24 wt.%), it would suggest possibility of an extraterrestrial impact over the Indian terrain during the erstwhile Gondwana sedimentation period that may be associated with the Permian-Triassic mass extinction, the most severe one in the Earth's history
The Statistical Face of a Region Under Monsoon Rainfall in Eastern India
No full textA region under rainfall is a contiguous spatial area receiving positive precipitation at a particular time. The probabilistic behavior of such a region is an issue of interest in meteorological studies. A region under rainfall can be viewed as a shape object of a special kind, where scale and rotational invariance are not necessarily desirable attributes of a mathematical representation. For modeling variation in objects of this type, we propose an approximation of the boundary that can be represented as a real valued function, and arrive at further approximation through functional principal component analysis, after suitable adjustment for asymmetry and incompleteness in the data. The analysis of an open access satellite dataset on monsoon precipitation over Eastern Indian subcontinent leads to explanation of most of the variation in shapes of the regions under rainfall through a handful of interpretable functions that can be further approximated parametrically. The most important aspect of shape is found to be the size followed by contraction/elongation, mostly along two pairs of orthogonal axes. The different modes of variation are remarkably stable across calendar years and across different thresholds for minimum size of the region. for this article, including a standardized description of the materials available for reproducing the work, are available as an online supplement
Parallel Factorization of Boolean Polynomials
No full textPolynomial factorization is a classical algorithmic problem in algebra, which has a wide range of applications. Of special interest is factorization over finite fields, among which the field of order two is probably the most important one due to the relationship to Boolean functions. In particular, factorization of Boolean polynomials corresponds to decomposition of Boolean functions given in the Algebraic Normal Form. It has been also shown that factorization provides a solution to decomposition of functions given in the full DNF (i.e., by a truth table), for positive DNFs, and for cartesian decomposition of relational datatables. These applications show the importance of developing fast and practical factorization algorithms. In the paper, we consider some recently proposed polynomial time factorization algorithms for Boolean polynomials and describe a parallel MIMD implementation thereof, which exploits both the task and data level parallelism. We report on an experimental evaluation, which has been conducted on logic circuit synthesis benchmarks and synthetic polynomials, and show that our implementation significantly improves the efficiency of factorization. Finally, we report on the performance benefits obtained from a parallel algorithm when executed on a massively parallel many core architecture (Redefine)
Convolutional Neural Networks for classifying skin lesions
No full textThe usage of Deep Learning has immensely increased in the present years. Convolutional Neural Networks, Recurrent Neural Networks, Generative Adversarial Networks, Variational Auto Encoders are among the prominent architectures in Deep Learning. Convolutional Neural Networks architecture has signified high accuracy and performance for image classification problems. On the other hand skin cancer if recognized or treated early is almost curable. The proposed model in the paper uses Convolutional Neural Networks to predict and classify seven different types of skin lesions. A website is developed for the real time usage of the model, which can predict the three most probable types of skin lesions for a given image. The observations and results are based on the experiment conducted using the MNIST:HAM10000 dataset which consists of 10000 labelled images