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Regulating drones in restricted spaces
No full textCommercial and end-user drones come equipped with a wide array of sensors. Unregulated use of such drones in public airspaces poses a serious threat to the privacy of citizens. We make the case for restricted spaces for drones, which are geographic areas for which a host can specify its privacy policies. Guest drones must prove to the host that they are in compliance with the host's policies before entering the restricted space. We then make the case for an information-flow control-based policy enforcement framework on drones, and sketch the design of a prototype framework atop the Robot Operating System (ROS). © 2019 ACM
Multifunctional Self-Assembled Macrocycles with Enhanced Emission and Reversible Photochromic Behavior
No full textA series of self-Assembled functional Pt(II) molecular hexagons (M1-M3) is reported. Hexagons M1 and M2 were designed employing aggregation induced emissive and photochromic building blocks, respectively, while macrocycle M3 is a bifunctional, containing both the kinds of building units. Hexagons M1 and M3 were found to inherit the enhanced emission with aggregate formation which was explored using UV-Vis and fluorescence spectroscopy. The enhanced emission of macrocycle M3 compared to that of its building units was driven both by metal-Ligand coordination and formation of nanoaggregates as evident from SEM, DLS and TEM analyses. Two of the macrocycles (M2 and M3) were also found to be photochromic due to the presence of spiropyran in the molecular backbone. Due to the virtue of protonation-Deprotonation equilibrium of the spiropyran, these macrocycles (M2 and M3) showed reversible acidochromic behavior. Macrocycle M3 represents the first example of a self-Assembled Pt(II) architecture which is multifunctional with aggregation-Induced emission (AIE), photochromic, and acidochromic properties. This new generation macrocycle (M3) also showed coordination-Driven enhanced emission and light-Induced color change behavior compared to the starting building blocks. Our present approach of incorporating multiple functions into a single self-Assembled structure with enhanced functionality compared to the starting building blocks via coordination self-Assembly is noteworthy and has huge potential for the development of multifunctional materials. © 2019 American Chemical Society
N 6 -Methyladenosine landscape of glioma stem-like cells: METTL3 is essential for the expression of actively transcribed genes and sustenance of the oncogenic signaling
No full textDespite recent advances in N 6 -methyladenosine (m 6 A) biology, the regulation of crucial RNA processing steps by the RNA methyltransferase-like 3 (METTL3) in glioma stem-like cells (GSCs) remains obscure. An integrated analysis of m 6 A-RIP (RNA immunoprecipitation) and total RNA-Seq of METTL3-silenced GSCs identified that m 6 A modification in GSCs is principally carried out by METTL3. The m 6 A-modified transcripts showed higher abundance compared to non-modified transcripts. Further, we showed that the METTL3 is essential for the expression of GSC-specific actively transcribed genes. Silencing METTL3 resulted in the elevation of several aberrant alternative splicing events. We also found that putative m 6 A reader proteins play a key role in the RNA stabilization function of METTL3. METTL3 altered A-to-I and C-to-U RNA editing events by differentially regulating RNA editing enzymes ADAR and APOBEC3A. Similar to protein-coding genes, lincRNAs (long intergenic non-coding RNAs) with m 6 A marks showed METTL3-dependent high expression. m 6 A modification of 30UTRs appeared to result in a conformation-dependent hindrance to miRNA binding to their targets. The integrated analysis of the m 6 A regulome in METTL3-silenced GSCs showed global disruption in tumorigenic pathways that are indispensable for GSC maintenance and glioma progression. We conclude that METTL3 plays a vital role in many steps of RNA processing and orchestrates successful execution of oncogenic pathways in GSCs. © 2019 by the authors. Licensee MDPI, Basel, Switzerland
Efficient FPGA Implementation of Multilayer Perceptron for Real-Time Human Activity Classification
No full textThe smartphone-based human activity recognition (HAR) systems are not capable to deliver high-end performance for challenging applications. We propose a dedicated hardware-based HAR system for smart military wearables, which uses a multilayer perceptron (MLP) algorithm to perform activity classification. To achieve the flexible and efficient hardware design, the inherent MLP architecture with parallel computation is implemented on FPGA. The system performance has been evaluated using the UCI human activity dataset with 7767 feature samples of 20 subjects. The three combinations of a dataset are trained, validated, and tested on ten different MLP models with distinct topologies. The MLP design with the 7-6-5 topology is finalized from the classification accuracy and cross entropy performance. The five versions of the final MLP design (7-6-5) with different data precision are implemented on FPGA. The analysis shows that the MLP designed with 16-bit fixed-point data precision is the most efficient MLP implementation in the context of classification accuracy, resource utilization, and power consumption. The proposed MLP design requires only 270 ns for classification and consumes 120 mW of power. The recognition accuracy and hardware results performance achieved are better than many of the recently reported works. © 2013 IEEE
Search for pair production of second-generation leptoquarks at ffiffi s p = 13 TeV
No full textA search for pair production of second-generation leptoquarks is performed using proton-proton
collision data collected at ffiffi
s p ¼ 13 TeV in 2016 with the CMS detector at the CERN LHC, corresponding
to an integrated luminosity of 35.9 fb−1. Final states with two muons and two jets, or with one muon, two
jets, and missing transverse momentum are considered. Second-generation scalar leptoquarks with masses
less than 1530(1285) GeV are excluded for β ¼ 1.0ð0.5Þ, where β is the branching fraction for the decay of
a leptoquark to a charged lepton and a quark. The results of the search are also interpreted as limits on the
pair production of long-lived top squarks in an R-parity violating supersymmetry model that has a final
state with two muons and two jets. These limits represent the most stringent limits to date on these models
Graph Spectral Properties of the Sidechain Networks of Protein Structures: Implications to Allostery and Structure Comparison
No full textAir-Stable Carbon-Fe Based Magnetic Nanostructures
No full textHerein, we report a simple solid state synthetic route to prepare carbon-Fe based magnetic nanoparticles with different compositions and morphologies through annealing of amorphous Fe nanoparticles under appropriate conditions. Tri-n-octylphosphine (TOP) capped amorphous Fe nanoparticles with a mean diameter of 3.2 nm were synthesized using solvated metal atom dispersion (SMAD) method. Annealing of as-prepared Fe nanoparticles at 300 °C produced carbon encapsulated crystalline bcc-Fe nanoparticles, whereas at higher temperatures i.e., 400 °C and 500 °C, spherical Fe 3 C/C core-shell nanoparticles were obtained. Annealing of as-prepared Fe nanoparticles in the presence of tri-n-octylphosphine oxide (TOPO) ligand under optimized conditions yielded rod shaped Fe 3 C/C core-shell morphology. The size, composition and particle morphology of these magnetic nanoparticles could be controlled by changing the reaction time, temperature and the concentration of the TOPO ligand. Magnetic measurements show that rod shaped Fe 3 C nanoparticles exhibit enhanced coercivity (Hc) values compared with spherical Fe 3 C nanoparticles, which is due to shape anisotropy. © 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei
Exploration of inositol 1,4,5-trisphosphate (IP3) regulated dynamics of N-terminal domain of IP3 receptor reveals early phase molecular events during receptor activation
No full textInositol 1, 4, 5-trisphosphate (IP3) binding at the N-terminus (NT) of IP3 receptor (IP3R) allosterically triggers the opening of a Ca2+-conducting pore located similar to 100 angstrom away from the IP3-binding core (IBC). However, the precise mechanism of IP3 binding and correlated domain dynamics in the NT that are central to the IP3R activation, remains unknown. Our all-atom molecular dynamics (MD) simulations recapitulate the characteristic twist motion of the suppressor domain (SD) and reveal correlated `clam closure' dynamics of IBC with IP3-binding, complementing existing suggestions on IP3R activation mechanism. Our study further reveals the existence of inter-domain dynamic correlation in the NT and establishes the SD to be critical for the conformational dynamics of IBC. Also, a tripartite interaction involving Glu283-Arg54-Asp444 at the SD - IBC interface seemed critical for IP3R activation. Intriguingly, during the sub-microsecond long simulation, we observed Arg269 undergoing an SD-dependent flipping of hydrogen bonding between the first and fifth phosphate groups of IP3. This seems to play a major role in determining the IP3 binding affinity of IBC in the presence/absence of the SD. Our study thus provides atomistic details of early molecular events occurring within the NT during and following IP3 binding that lead to channel gating
Estimation of time-variant system reliability of nonlinear randomly excited systems based on the Girsanov transformation with state-dependent controls
No full textThe problem of time-variant system reliability analysis of nonlinear dynamical systems subjected to random excitations is considered. The governing equations are formulated as a set of Ito's stochastic differential equations. Subsequently, a Monte Carlo simulation strategy, which incorporates Girsanov's transformation- based variance reduction step, is developed. The novel element of the work lies in the formulation of state-dependent Girsanov's control forces for estimating the system reliability. The study considers failure modes arranged in series, parallel, or composite configurations. Illustrative examples include studies on a 5-dof Duffing's system and an inelastic frame subjected to multi-support, non-stationary, Gaussian excitations. The numerical results demonstrate significant variance reduction achieved in estimating low probabilities of failure
NO2 gas sensing performance enhancement based on reduced graphene oxide decorated V2O5 thin films
No full textHere, we demonstrate improved NO2 gas sensing properties based on reduced graphene oxide (rGO) decorated V2O5 thin film. Excluding the DC sputtering grown V2O5 thin film, rGO was spread over V2O5 thin film by the drop cast method. The formation of several p-n heterojunctions was greatly affected by the current-voltage relation of the rGO-decorated V2O5 thin film due to the p-type and n-type nature of rGO and V2O5, respectively. Initially with rGO decoration on V2O5 thin film, current decreased in comparison to the pristine V2O5 thin film, whereas depositing rGO film on a glass substrate drastically increased current. Among all sensors, only the rGO-decorated V2O5 sensor revealed a maximum NO2 gas sensing response for 100 ppm at 150 degrees C, and it achieved an approximately 61% higher response than the V2O5 sensor. The elaborate mechanism for an extremely high sensing response is attributed to the formation and modulation of p-n heterojunctions at the interface of rGO and V2O5. In addition, the presence of active sites like oxygenous functional groups on the rGO surface enhanced the sensing response. On that account, sensors based on rGO-decorated V2O5 thin film are highly suitable for the purpose of NO2 gas sensing. They enable the timely detection of the gas, further protecting the ecosystem from its harmful effects