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Generalized explicit guidance with optimal time-to-go and realistic final velocity
No full textThis paper presents an approach to compute the optimal time-to-go and final velocity magnitude in the Generalized Explicit (GENEX) guidance. Time-to-go and final velocity magnitude are two critical input parameters in GENEX guidance implementation. Optimal time-to-go selects that optimal solution which yields less cost compared to the costs yielded by other optimal solutions. In addition to it, the input of realistic final velocity lowers the cost further. These developments relax the existing limitations of GENEX, thereby making this optimal guidance law more optimal, effective and generic
Superior potassium-ion hybrid capacitor based on novel P3-type layered K0.45Mn0.5Co0.5O2 as high capacity cathode
No full textHerein, we demonstrate a new non-aqueous potassium-ion hybrid capacitor (KIC) using novel P3-K0.45Mn0.5Co0.5O2 and commercial activated carbon (CAC) as the cathode and anode, respectively. A simple sol-gel method is used to synthesize the P3-K0.45Mn0.5Co0.5O2 cathode nanoplatelets. The structural and morphological studies are performed using various characterization techniques, and their electrochemical performances are studied in half-cell configurations against metallic K. The P3-K0.45Mn0.5Co0.5O2 nanoplatelets can reversibly host K+ ions delivering a high capacity of 140 mAh g(-1) in the wide voltage window of 1.2-3.9 V. Exhibiting smooth voltage profiles, it offers reasonable rate capability and cyclability, retaining over 80% capacity after 50 cycles. Involving a two-phase (P3-O3) redox mechanism, P3-K0.45Mn0.5Co0.5O2 forms robust cathode material for potassium-ion batteries. With Activated Carbon, the capacitor could provide very high energy and power densities of 43 Wh kg(-1) and 30 kW kg(-1), respectively, in the voltage range of 0-3.0 V. Even at a 3-s charge-discharge rate (10 A g(-1)), an energy density of 14.5 Wh kg(-1) could be retained (corresponding to a power of 15 kW kg(-1)). Also it could retain 88% of its energy density with a substantially high stability up to 30,000 cycles at 10 A g(-1)
Experimental Investigation on Behavior of a Laterally Loaded Single Pile Located on Sloping Ground
No full textLaboratory model tests were conducted on an aluminum model pile embedded on a crest of soft clay. The slope angle and L/D ratio (L = embedded length, D = diameter of pile) were varied, and the pile was subjected to lateral loads at the pile head by a loading frame and frictionless pulley arrangements. Through the experimental investigation, the effect of the L/D ratio and slope on the behavior of the pile was studied. To incorporate the effect of slopes and L/D ratios, an empirical equation was also developed with the use of multiple regression analysis. It was observed that as the ground slope changed fromlevel to a 1V:5H slope (11.30 degrees), the influence of the slope on pile capacity became negligible. (C) 2019 American Society of Civil Engineers
Interaction of the intrinsically disordered C-terminal domain of the sesbania mosaic virus RNA-dependent RNA polymerase with the viral protein P10 in vitro: modulation of the oligomeric state and polymerase activity
No full textThe RNA-dependent RNA polymerase (RdRp) of sesbania mosaic virus (SeMV) was previously shown to interact with the viral protein P10, which led to enhanced polymerase activity. In the present investigation, the equilibrium dissociation constant for the interaction between the two proteins was determined to be 0.09 mu M using surface plasmon resonance, and the disordered C-terminal domain of RdRp was shown to be essential for binding to P10. The association with P10 brought about a change in the oligomeric state of RdRp, resulting in reduced aggregation and increased polymerase activity. Interestingly, unlike the wild-type RdRp, C-terminal deletion mutants (C del 43 and C del 72) were found to exist predominantly as monomers and were as active as the RdRp-P10 complex. Thus, either the deletion of the C-terminal disordered domain or its masking by binding to P10 results in the activation of polymerase activity. Further, deletion of the C-terminal 85 residues of RdRp resulted in complete loss of activity. Mutation of a conserved tyrosine (RdRp Y480) within motif E, located between 72 and 85 residues from the C-terminus of RdRp, rendered the protein inactive, demonstrating the importance of motif E in RNA synthesis in vitro
Deuterium isotope effect in fluorescence of gaseous oxazine dyes
No full textThe increased utility of fluorescence-based methods in recent years has highlighted the need for brighter, more efficient fluorophores. In order to design these fluorophores, an improved fundamental understanding is necessary of the structural components that intrinsically effect fluorescence efficiency. Here, we characterize the intrinsic effects of deuteration on fluorescence from gaseous oxazine dyes, without the influence of dye-solvent interactions, by making use of an ion trap mass spectrometer that has been altered to enable optical measurements. Comparison of emission spectra of four oxazine dyes: cresyl violet, oxazine 4, oxazine 170, and darrow red, show little change in profile upon deuteration of amine groups. However, deuteration significantly increases the efficiency of fluorescence with an increase in fluorescence lifetime and brightness by 10-23% for the gaseous dyes. This increase is less than half that of the quantum yield increase observed in deuterated solution. This indicates the large fluorescence efficiency changes for the oxazine dyes in deuterated solution result from a combination of both intrinsic effects as well as substantial contribution from altered fluorophore-solvent interactions. The intrinsic effects behind increased lifetime upon deuteration are explored using time-dependent density functional theory (TD-DFT) calculations of potential energy surfaces (PESs) for ground and low lying excited electronic states. In accord with experimental observations, calculated S-1-S-0 emission spectra show only minor differences between deuterated and non-deuterated forms indicating that the deuteration does not affect the radiative channel appreciably. Relaxed PES scans along the torsional motions of the amino groups reveal that the increase in lifetimes upon deuteration is likely due to quenching of different radiationless changes channels in different oxazine dyes. Calculations suggest that tunneling to access twisted intramolecular charge transfer states in S-1 is critical in several of the oxazines. However, in at least one of the dyes examined, the large isotope effect is more likely due to differences in intersystem crossing rates. Overall, this combined experimental and computational investigation elucidates the photophysics of a well-known fluorescent scaffold and provides insight into how small differences can dramatically affect fluorescence outcomes
Ionic conductivity in aqueous electrolyte solutions: Insights from computer simulations
No full textThere exist a large amount of data on conductivity of various ions in aqueous and non-aqueous solvents as a function of ionic radius, pressure, temperature, ionic concentration, etc. Because of its importance in chemistry, biology, electrochemistry and a number of other areas, a consistent picture of how the various factors influence the conductivity is essential. We present detailed molecular dynamics simulations of ions in water in order to understand the influence of three factors: (i) ionic radius (ii) temperature and (iii) pressure. We propose an alternative explanation for the variation of ionic conductivity as a function of ionic radius for ions in water. The explanation is based on the Levitation Effect which arises from mutual cancellation of forces on the diffusant or ions when the ions are of the same radius as the bottleneck present in the solvent. This theoretical framework not only accounts for the variation of conductivity with ionic radius but also its variation with pressure. Experimental data on variation of ionic conductivity shows contrasting dependence on pressure for ions of different radius. We show that the proposed theoretical framework also accounts for the variation of ionic conductivity as a function of pressure for ions of different radius. Thus, we have been able to propose a theoretical framework which unifies our understanding of three different factors, namely, ionic radius, temperature and pressure. (C) 2018 Elsevier B.V. All rights reserved
Facile enantiospecific syntheses of oxabicyclo4.4.0]decene-diones from carvone via mild Lewis acid mediated lactonizations
No full textAn efficient and concise enantiospecific syntheses of oxabicyclo4.4.0]decene-diones have been accomplished starting from carvone. This strategy is a chiron based approach by making use of mild Lewis acid mediated intramolecular lactonization as key step for the formation of fused bicyclic lactones. Notably, these bicyclic lactones constitute bicyclic carbon framework of diterpene natural products
Disguised Facial Recognition Using Neural Networks
No full textIn this paper, we present a real-time deep neural network architecture (called DiFRuNNT) for disguised face verification. The proposed model consists of two neural networks, first one being a convolutional neural network (CNN) that predicts 20 facial key-points in the image and the second neural network classifies the subject based on the angles and ratios calculated from the predicted points. The accuracies are 67.4% and 74.8% for prediction and classification respectively and the results have been compared with the state-of-the-art methodologies also
Search for a W ` boson decaying to a tau lepton and a neutrino in proton-proton collisions at root s=13 TeV
No full textA search for a new high-mass resonance decaying to a tau lepton and a neutrino is reported. The analysis uses proton-proton collision data collected by the CMS experiment at the LHC at root s= 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1). The search utilizes hadronically decaying tau leptons. No excess in the event yield is observed at high transverse masses of the tau and missing transverse momentum. An interpretation of results within the sequential standard model excludes W' boson masses below 4.0 TeV at 95% confidence level. Existing limits are also improved on models in which the W' boson decays preferentially to fermions of the third generation. Heavy W' bosons with masses less than 1.7-3.9 TeV, depending on the coupling in the non-universal G(221) model, are excluded at 95% confidence level. These are the most stringent limits on this model to date. (C) 2019 The Author(s). Published by Elsevier B.V
How Do Trait-Mediated Non-lethal Effects of Predation Affect Population-Level Performance of Mosquitoes?
No full textNon-lethal, trait-mediated effects of predation impact prey behavior and life-history traits. Studying how these effects in turn influence prey demography is crucial to understand prey life-history evolution. Mosquitoes are important vectors that claim several million lives every year worldwide by transmitting a range of pathogens. Several ecological factors affect life-history traits of both larval and adult mosquitoes, creating effects that cascade to population-level consequences. Few studies have comprehensively explored the non-lethal effects of predation and its interactions with resources and competition on larval, adult, and population traits of mosquitoes. Understanding these interactions is important because the effects of predation are hypothesized to rescue prey populations from the effects of density-dependence resulting from larval competition. Aedes aegypti larvae reared at two different larval densities and subjected to three non-lethal predator treatments were monitored for survival, development time, and adult size through the larval stages to adult eclosion, and adult females were monitored for survival and reproduction through their first gonotrophic cycle. Intraspecific competition increased larval development time, yielded small-bodied adults, and reduced fecundity in individuals exposed to predatory chemical cues as larvae. Exposure to cues from a living predator affected both body size and latency to blood feed in females. Analysis of life-table traits revealed significant effects of competition on net reproductive rate (R-0) of mosquitoes. The interaction between competition and predator treatments significantly affected the cohort rate of increase (r) and the index of performance (r'). The index of performance, which estimates rate of population change based on the size-fecundity relationship, was significantly and positively correlated with r, but overestimated r slightly. Lack of significant effect of predator treatments and larval density on cohort generation time (T-c) further suggests that the observed effects of treatments on r and r' were largely a consequence of the effects on R-0. Also, the significant effects of treatment combinations on larval development time, adult body size and fecundity were ultimately manifested as effects on life-table traits estimated from adult survival and reproduction