Abstract
We autonomously directed a small quadcopter package delivery Uncrewed Aerial Vehicle (UAV) or “drone” to take off, fly a specified route, and land for a total of 209 flights while varying a ...set of operational parameters. The vehicle was equipped with onboard sensors, including GPS, IMU, voltage and current sensors, and an ultrasonic anemometer, to collect high-resolution data on the inertial states, wind speed, and power consumption. Operational parameters, such as commanded ground speed, payload, and cruise altitude, were varied for each flight. This large data set has a total flight time of 10 hours and 45 minutes and was collected from April to October of 2019 covering a total distance of approximately 65 kilometers. The data collected were validated by comparing flights with similar operational parameters. We believe these data will be of great interest to the research and industrial communities, who can use the data to improve UAV designs, safety, and energy efficiency, as well as advance the physical understanding of in-flight operations for package delivery drones.
Ordered mesoporous silica spheres (MCM-41) were used as fillers in polyimide (Matrimid) based mixed-matrix membranes (MMMs). The filler particles were functionalized with sulfonic acid (–SO3H) groups ...to increase the separation performance of the membranes by increasing the CO2 solubility. The fast diffusion of gases through the mesoporous materials, accompanied by this increased interaction with CO2, resulted in the simultaneous increase of gas permeability and selectivity. The functionalized membranes showed up to 31% increase in CO2 permeability and 14% increase in CO2/CH4 selectivity. In order to study the stability of these newly developed MMMs, they were tested at different operating conditions (temperatures, mixed-gas feeds and CO2 feed concentration).
•MMMs based on Matrimid and –SO3H functionalized.•Good dispersion of the functionalized fillers in the polymer matrix.•Significant increase in permeability and selectivities was obtained.
Sugars are the major source of energy in living organisms and play important roles in osmotic regulation, cell signaling and energy storage. SWEETs (Sugars Will Eventually be Exported Transporters) ...are the most recent family of sugar transporters that function as uniporters, facilitating the diffusion of sugar molecules across cell membranes. In plants, SWEETs play roles in multiple physiological processes including phloem loading, senescence, pollen nutrition, grain filling, nectar secretion, abiotic (drought, heat, cold, and salinity) and biotic stress regulation. In this review, we summarized the role of SWEET transporters in plant development and abiotic stress. The gene expression dynamics of various SWEET transporters under various abiotic stresses in different plant species are also discussed. Finally, we discuss the utilization of genome editing tools (TALENs and CRISPR/Cas9) to engineer SWEET genes that can facilitate trait improvement. Overall, recent advancements on SWEETs are highlighted, which could be used for crop trait improvement and abiotic stress tolerance.
Even though doping small sized NCs is a challenging task, 2.7 nm sized tin oxide (SnO
2
) nanocrystals (NCs) are successfully doped with cobalt (Co). Studies are carried out in dilutely Co-doped SnO
...2
NCs, so as to avoid Co cluster formation and interference due to extrinsic effect. Co
2+
ions are substitutionally doped in SnO
2
lattice as seen from the
d
-
d
transitions in optical absorption spectra. Further x-ray photoelectron spectroscopic measurements also confirm Co
2+
ionic state in SnO
2
NCs. In view of the known fact that ferromagnetism in NCs arises due to different defects, Raman measurements are carried out. Raman spectra reveal presence of “in-plane” oxygen vacancies, which is also substantiated by photoluminescence spectra. Even though, Co-doping is not profoundly affecting the structure of SnO
2
NCs, subtle ferromagnetic ordering observed in un-doped NCs get destroyed in Co-doped NCs. The present work reiterates the importance of Co-Co anti-ferromagnetic interaction and also indirectly supports the conjecture that oxygen vacancies adjacent with Co ions in SnO
2
lattice in a necessary condition for realizing ferromagnetic ordering.
Presented work describes the symmetrical quad-element Multiple-Input Multiple-Output (MIMO) antenna operating at 28 GHz for Fifth generation (5G) millimeter-wave (mm-wave) spectrum. The core of this ...antenna system features a stepped-shaped patch radiator precisely tuned to 28 GHz, effectively broadening its resonance across the desired operational frequency band. To improve isolation, an Isolating Metallic Sheet (IMS) is precisely placed between the patch radiators of projected antenna. Rogers RT5880 substrate is used to fabricate with dimensions of 20.48 × 20.48 mm2, thickness of 1.6 mm, and dielectric constant of 2.2. Both simulationand measurement outcomesindicate that the antenna has a bandwidth of 7.13 GHz, covering frequencies ranging from 25.21 GHz to 32.34 GHz, for a fractional bandwidth of 24.78 %. Key antenna performance measurements include a peak amplitude of up to 53 dB and a significant port-to-port isolation of more than 20 dB. Ithasbeen carefully examined revealing a minimum channel capacity loss of 0.135 bits/s/Hz, a mean effectivegain of −3 dB, a diversity gain of around 10 dB, a total active reflection coefficient of −10 dB, and an envelope correlation coefficient of less than 0.005. Presentedantenna meets industrial requirementsfor high-speed mm-wave communications in 28 GHz 5G networks.
The importance of biological agents has been recognized as a promising tool for green synthesis of silver nanoparticles over conventional physiochemical methods that are laden with various type of ...drawbacks. The biomediated nanoparticles synthesis chiefly employing microorganisms and plants as nanofactories is gaining worldwide popularity over past few decades. Biosynthesized silver nanoparticles have demonstrated desirable physical and chemical and antimicrobial properties among other metallic nanoparticles. This article represents a comprehensive review of biosynthesis route for silver nanoparticles formation including the mechanism, extra- and intra-cellular types and remarkable outcomes of previously conducted research works on biosynthesis. Broad antimicrobial spectra including antibacterial, antifungal, antiviral, sporicidal of biosynthesized silver nanoparticles with major emphasis on their potential applications in biocatalysis, biosensing, food packaging and preservation, pest killing and plant growth promotion, biomedicine and diagnostics etc. have been discussed. Moreover, this article also encompasses meticulous description on challenges and future prospects of biosynthesis of nanoparticles.
Förster resonance energy transfer (FRET) with fluorescent proteins permits high spatial resolution imaging of protein–protein interactions in living cells. However, substantial non-FRET fluorescence ...background can obscure small FRETsignals, making many potential interactions unobservable by conventional FRET techniques. Here we demonstrate time-resolved microscopy of luminescence resonance energy transfer (LRET) for live-cell imaging of protein– protein interactions. A luminescent terbium complex, TMP-Lumi4, was introduced into cultured cells using two methods: (i) osmotic lysis of pinocytic vesicles; and (ii) reversible membrane permeabilization with streptolysin O. Upon intracellular delivery, the complex was observed to bind specifically and stably to transgenically expressed Escherichia coli dihydrofolate reductase (eDHFR) fusion proteins. LRET between the eDHFR-bound terbium complex and green fluorescent protein (GFP) was detected as long-lifetime, sensitized GFP emission. Background signals from cellular autofluorescence and directly excited GFP fluorescence were effectively eliminated by imposing a time delay (10 μs) between excitation and detection. Background elimination made it possible to detect interactions between the first PDZ domain of ZO-1 (fused to eDHFR) and the C-terminal YV motif of claudin-1 (fused to GFP) in single microscope images at subsecond time scales. We observed a highly significant (P < 10⁻⁶), six-fold difference between the mean, donornormalized LRET signal from cells expressing interacting fusion proteins and from control cells expressing noninteracting mutants. The results show that time-resolved LRET microscopy with a selectively targeted, luminescent terbium protein label affords improved speed and sensitivity over conventional FRET methods for a variety of live-cell imaging and screening applications.
Surface-enhanced Raman spectroscopy (SERS) has developed as a feasible method for chemical and biological applications, unifying the precision of molecular fingerprinting with the potential ...sensitivity of single molecules. SERS has shown promise as a chemical and biological detection tool, but like all other methods, it has some limitations. These include brittle and fragile SERS substrates, poor adhesion of the thin film to the substrates, limited reusability of the substrates, and inhomogeneity and irreproducibility of signals within a substrate. Recently, sculptured thin films fabricated by glancing angle deposition (GLAD) have attracted considerable interest due to their potential use in plasmonics and the fabrication of highly uniform and sensitive SERS substrates. Using GLAD, the structure of the nanocolumns can be customized by changing the deposition parameters (such as gas pressure, tilt angle, and substrate rotation), resulting in a range of different properties. Recently, GLAD has become an important approach for fabricating nanocolumnar and aligned structures for SERS. Moreover, because the GLAD process is simple, inexpensive, and easy to produce on a large scale, it can expand the use of these substrates. The main objective of this review is to explain the fabrication and application of various SERS substrates using GLAD and to discuss how SERS substrates prepared using GLAD have overcome some of the limitations of SERS substrates. We begin with a brief overview of SERS and the SERS amplification process. We shall then briefly discuss the GLAD technique. Finally, we will discuss how various nanostructured SERS substrates by GLAD overcome the limitations of SERS substrates.
Genome wide association study (GWAS) was conducted for 14 agronomic traits in wheat following widely used single locus single trait (SLST) approach, and two recent approaches viz. multi locus mixed ...model (MLMM), and multi-trait mixed model (MTMM). Association panel consisted of 230 diverse Indian bread wheat cultivars (released during 1910-2006 for commercial cultivation in different agro-climatic regions in India). Three years phenotypic data for 14 traits and genotyping data for 250 SSR markers (distributed across all the 21 wheat chromosomes) was utilized for GWAS. Using SLST, as many as 213 MTAs (p ≤ 0.05, 129 SSRs) were identified for 14 traits, however, only 10 MTAs (~9%; 10 out of 123 MTAs) qualified FDR criteria; these MTAs did not show any linkage drag. Interestingly, these genomic regions were coincident with the genomic regions that were already known to harbor QTLs for same or related agronomic traits. Using MLMM and MTMM, many more QTLs and markers were identified; 22 MTAs (19 QTLs, 21 markers) using MLMM, and 58 MTAs (29 QTLs, 40 markers) using MTMM were identified. In addition, 63 epistatic QTLs were also identified for 13 of the 14 traits, flag leaf length (FLL) being the only exception. Clearly, the power of association mapping improved due to MLMM and MTMM analyses. The epistatic interactions detected during the present study also provided better insight into genetic architecture of the 14 traits that were examined during the present study. Following eight wheat genotypes carried desirable alleles of QTLs for one or more traits, WH542, NI345, NI170, Sharbati Sonora, A90, HW1085, HYB11, and DWR39 (Pragati). These genotypes and the markers associated with important QTLs for major traits can be used in wheat improvement programs either using marker-assisted recurrent selection (MARS) or pseudo-backcrossing method.
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