gebhart/patrepeval huggingface dataset:
Oxidative damage to nuclear DNA: amelioration by melatonin. NEL Review. (1999)

The indoleamine melatonin, a product of tryptophan metabolism in the pineal gland, is a free radical scavenger and antioxidant. This brief review summarizes melatonin's ability to protect nuclear DNA from oxidative damage. Using a variety of different cytogenetic, biochemical and molecular biological methods, a number of investigators have demonstrated melatonin's ability to protect DNA from the physical agent ionizing radiation, the herbicide paraquat, the carcinogen safrole, the excitotoxin kainic acid, the heavy metal chromium (VI), and a wide number of mutagens. Since these agents damage DNA because they generate free radicals, the observations are consistent with melatonin being a radical scavenger and antioxidant.
Applications of AFM Sample Stretching Stage to Commercial Impact Copolymer (2011)

The morphology and interfacial adhesion of a polypropylene-based impact copolymer were studied using atomic force microscopy with a tensile stage. Effects of deformation as a func tion of tensile stress were observed within both polypropylene (PP) and ethylene pro plyene (EP) components as well as at the inter face between the two materials. Most impor tantly, EP-PP interfacial strength can be mea sured by the corresponding local interfacial stretching extent or void length between EP and PP as the EP domains separate from the PP matrix upon delamination. Presently, there are no direct measurement methods available to determine interfacial adhesive strength of nano- and microscale domains within poly mer blends, especially blends generated in situ in polymerization reactors where individ ual materials cannot be accessed directly. This approach could be used for direct determina tion of interfacial adhesion in complex poly mer-containing materials such as blends and nanocomposites.
DOUBLE-PORT SLOTTED-ANTENNA WITH MULTIPLE MINIATURIZED RADIATORS FOR WIDEBAND WIRELESS COMMUNICATION SYSTEMS AND PORTABLE DEVICES (2019)

Proof-of-concept is presented of a novel slot antenna structure with two excitation ports. Although this antenna provides a wide impedance bandwidth, its peak gain and optimum radiation eﬃciency are observed at its mid-band operational frequency. The antenna structure is etched on the top side of a dielectric substrate with a ground plane. The antenna essentially consists of a rectangular patch with two dielectric slots in which multiple coupled patch arms embedded with H-shaped slits are loaded. The two dielectric slots are isolated from each other with a large H-shaped slit. The radiation characteristics of the proposed antenna in terms of impedance bandwidth, gain and eﬃciency can be signiﬁcantly improved by simply increasing the number of radiation arms and modifying their dimensions. The antenna’s performance was veriﬁed by building and testing three prototype antennas. The ﬁnal optimized antenna exhibits a fractional bandwidth of 171% (0.5–6.4GHz) with a peak gain and maximum radiation eﬃciency of 5.3dBi and 75% at 4.4GHz, respectively. The antenna has physical dimensions of 27×37×1.6mm 3 corresponding to electrical size of 0.0452λ0×0.0627λ0×0.0026λ0, where λ 0 is free space wavelength at 0.5GHz. The antenna is compatible for integration in handsets and other broadband wireless systems that operate over L-, S-, and C-bands.
1.5 μm InGaAsP/InP buried crescent superluminescent diode on a p-InP substrate (1990)

An InGaAsP/InP superluminescent diode (SLD) emitting at 1.54 μm has been fabricated. The device uses a buried crescent structure on a p-InP substrate. The parameters were optimized for high output power, small spectral modulation, and smooth far-field operation. The coherence function of the SLD emission was studied systematically. An output power of 5 mW, a coherence length of 41 μm, and a second coherence peak suppression ratio of 22 dB were obtained.
Surfactant-Free Synthesized Magnetic Polypropylene Nanocomposites: Rheological, Electrical, Magnetic, and Thermal Properties (2011)

A facile surfactant-free process is introduced to prepare multifunctional polypropylene (PP) nanocomposites filled with highly dispersed Fe@Fe2O3 core@shell nanoparticles (NPs). Transmission electron microscopy (TEM) observations confirm the formation of uniform NPs in the PP matrix and the particle size increases with increasing the particle loading. The melt rheology measurements show an obvious change in the frequency dependent storage modulus (G′), loss modulus (G′′) and complex viscosity (η*) particularly at low frequencies. These changes are often related to the filler “percolation threshold”, which has also been verified in the sharp change of electrical resistance and dielectric permittivity of these nanocomposites in higher particle loadings. The continuous decrease in the resistivity with increasing filler loading from 5 wt % to 20 wt % demonstrates the structural transition of the nanocomposites. The monotonic increase in the dielectric permittivity with increasing particle loadings combined with the direct evidence from the TEM observations indicate that the NPs are well separated and uniformly dispersed in the polymer matrix. Thermal gravimetric analysis (TGA) results reveal a surprisingly high enhancement of the thermal stability by ∼120 °C in air due to the oxygen trapping effect of the NPs and the polymer–particle interfacial interaction. The differential scanning calorimetry (DSC) results show that the crystalline temperature (Tc) of the nanocomposites is reduced by 16–18 °C as compared to that of PP, while the melting temperature (Tm) almost maintains the same. The nanocomposites is found to be soft ferromagnetic at room temperature.
Mapping RNA exit channel on transcribing RNA polymerase II by FRET analysis (2008)

A simple genetic tag-based labeling method that permits specific attachment of a fluorescence probe near the C terminus of virtually any subunit of a protein complex is implemented. Its immediate application to yeast RNA polymerase II (pol II) enables us to test various hypotheses of RNA exit channel by using fluorescence resonance energy transfer (FRET) analysis. The donor dye is labeled on a site near subunit Rpb3 or Rpb4, and the acceptor dye is attached to the 5' end of RNA transcript in the pol II elongation complex. Both in-gel and single-molecule FRET analysis show that the growing RNA is leading toward Rpb4, not Rpb3, supporting the notion that RNA exits through the proposed channel 1. Distance constraints derived from our FRET results, in conjunction with triangulation, reveal the exit track of RNA transcript on core pol II by identifying amino acids in the vicinity of the 5' end of RNA and show that the extending RNA forms contacts with the Rpb7 subunit. The significance of RNA exit route in promoter escape and that in cotranscriptional mRNA processing is discussed.
Calcium deposition in osteoarthritic meniscus and meniscal cell culture (2010)

Calcium deposition is common in OA menisci. OA meniscal cells calcify more readily than normal meniscal cells. Pathological meniscal calcification, which may alter the biomechanical properties of the knee meniscus, is potentially an important contributory factor to OA.
A multi-piecewise curvature-corrected technique for bandgap reference circuits (2013)

A systematic design methodology utilizing piecewise curvature correction technique for the purpose of improving the temperature coefficient of bandgap references (BGRs) is presented in this paper. It is shown that the temperature dependency of the drain current of a MOSFET transistor depends on the transistor's operating region. Using this property, a multi-piecewise compensation technique over wide temperature range is achieved by controlling the operating region of MOSFETs through their gate-source voltages. The technique offers several advantages including simplicity, and providing the designers with flexibility to employ a combination of piecewise currents to achieve maximum temperature stability over the desired temperature range. To demonstrate the capability of this approach, the technique is used to effectively reduce the temperature coefficient of a first-order BGR circuit.
Mo6S8-based single-metal-atom catalysts for direct methane to methanol conversion (2019)

The single atom catalysts have been attracting much attention for catalysis. In this work, the significant influence of single-metal-atom (M = K, Ti, Fe, Co, Ni, Cu, Rh) doping on a Mo<sub>6</sub>S<sub>8</sub> cluster was revealed for the direct methane to methanol conversion in water stream using density functional theory calculations. It was found that all single atom dopants help to facilitate the conversion via the steam reforming of methane (SRM). The single Fe atom on Mo<sub>6</sub>S<sub>8</sub> (Fe-Mo<sub>6</sub>S<sub>8</sub>) exhibits the most significant promoting effect, which is followed by Ni, Co, Rh-Mo<sub>6</sub>S<sub>8</sub> > K, Ti, Cu-Mo<sub>6</sub>S<sub>8</sub> > Mo<sub>6</sub>S<sub>8</sub> in a decreasing sequence. The enhanced activity by single atom doping on Mo<sub>6</sub>S<sub>8</sub> is mainly associated with the interplay between the ensemble effect via the direct participation of an active M dopant and the site confinement imposed by doping of a single M atom, in tuning the methane conversion and methanol selectivity. It generates the new active center, M, which confines the SRM to occur at the M-Mo bridge sites and facilitates the selective production of methanol. A good single-atom promoter should not only bind <sup>*</sup>OH or <sup>*</sup>O moderately, being strongly enough to help water dissociation and weakly enough to allow the oxidation of methane, but also impose the confinement effect to facilitate the C-O bond association and production of methanol. Our results highlight the importance of the interplay among ligand, ensemble, and confinement effects in promoting the complex SRM over single atom catalysts.
Expression of the Mitotic Motor Protein Eg5 in Postmitotic Neurons: Implications for Neuronal Development (1998)

It is well established that the microtubules of the mitotic spindle are organized by a variety of motor proteins, and it appears that the same motors or closely related variants organize microtubules in the postmitotic neuron. Specifically, cytoplasmic dynein and the kinesin-related motor known as CHO1/MKLP1 are used within the mitotic spindle, and recent studies suggest that they are also essential for the establishment of the axonal and dendritic microtubule arrays of the neuron. Other motors are required to tightly regulate microtubule behaviors in the mitotic spindle, and it is attractive to speculate that these motors might also help to regulate microtubule behaviors in the neuron. Here we show that a homolog of the mitotic kinesin-related motor known as Eg5 continues to be expressed in rodent neurons well after their terminal mitotic division. In neurons, Eg5 is directly associated with the microtubule array and is enriched within the distal regions of developing processes. This distal enrichment is transient, and typically lost after a process has been clearly defined as an axon or a dendrite. Strong expression can resume later in development, and if so, the protein concentrates within newly forming sprouts at the distal tips of dendrites. We suggest that Eg5 generates forces that help to regulate microtubule behaviors within the distal tips of developing axons and dendrites.
Transposition-Driven Genomic Heterogeneity in the Drosophila Brain (2013)

Recent studies in mammals have documented the neural expression and mobility of retrotransposons and have suggested that neural genomes are diverse mosaics. We found that transposition occurs among memory-relevant neurons in the Drosophila brain. Cell type-specific gene expression profiling revealed that transposon expression is more abundant in mushroom body (MB) αβ neurons than in neighboring MB neurons. The Piwi-interacting RNA (piRNA) proteins Aubergine and Argonaute 3, known to suppress transposons in the fly germline, are expressed in the brain and appear less abundant in αβ MB neurons. Loss of piRNA proteins correlates with elevated transposon expression in the brain. Paired-end deep sequencing identified more than 200 de novo transposon insertions in αβ neurons, including insertions into memory-relevant loci. Our observations indicate that genomic heterogeneity is a conserved feature of the brain.
On-demand loop-free routing with link vectors (2005)

We present the on-demand link vector (OLIVE) protocol, a routing protocol for ad hoc networks based on link-state information that is free of routing loops and supports destination-based packet forwarding. Routers exchange routing information reactively for each destination in the form of complete paths, and each node creates a labeled source graph based on the paths advertised by its neighbors. A node originates a broadcast route request (RREQ) to obtain a route for a destination for which a complete path does not exist in its source graph. When the original path breaks, a node can select an alternative path based on information reported by neighbors, and a node can send a unicast RREQ to verify that the route is still active. A node that cannot find any alternate path to a destination sends route errors reliably to those neighbors that were using it as next hop to the destination. Using simulation experiments in ns2, OLIVE is shown to outperform dynamic source routing, ad hoc on-demand distance vector, optimized link-state routing protocol, and topology broadcast based on reverse-path forwarding, in terms of control overhead, throughput, and average network delay, while maintaining loop-free routing with no need for source routes.
640$\,\times\,$512 Pixels Long-Wavelength Infrared (LWIR) Quantum-Dot Infrared Photodetector (QDIP) Imaging Focal Plane Array (2007)

Epitaxially grown self-assembled InAs-InGaAs-GaAs quantum dots (QDs) are exploited for the development of large-format long-wavelength infrared focal plane arrays (FPAs). The dot-in-a-well (DWELL) structures were experimentally shown to absorb both 45deg and normal incident light, therefore, a reflection grating structure was used to enhance the quantum efficiency. The devices exhibit peak responsivity out to 8.1 mum, with peak detectivity reaching ~1times10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">10</sup> Jones at 77 K. The devices were fabricated into the first long-wavelength 640times512 pixel QD infrared photodetector imaging FPA, which has produced excellent infrared imagery with noise equivalent temperature difference of 40 mK at 60-K operating temperature
Lower bounds of the Kirchhoff and degree Kirchhoff indices (2015)

Let G be an undirected connected graph with n, n ≥ 3, vertices and m edges. If μ1 ≥ μ2 … ≥ μn-1 > μn = 0 and ρ1 ≥ ρ2 ≥ …≥ ρn-1 > ρn = 0 are the Laplacian and the normalized Laplacian eigenvalues of G, then the Kirchhoff and the degree Kirchhoff indices obey the relations K ƒ (G) = nΣn-1 i=1 μ-1 i and DK ƒ (G) = 2mΣn-1 i=1 ρ-1 i-1, respectively. The inequalities that determine lower bounds for some invariants of G, that contain K ƒ (G) and DK ƒ (G), are obtained in this paper. Lower bounds for K ƒ (G) and DK ƒ (G), known in the literature, are obtained as a special case.
Stimulated emission and lasing in π-conjugated polymer films, microstructures, and opal photonic crystals (1999)

Recent studies of lasing and stimulated emission in luminescent (pi) -conjugated polymers performed by our group are presented. Optical properties of cylindrical, high-Q, polymer microcavities are discussed. The emission spectra of plastic microring and microdisk lasers were measured and analyzed. Cylindrical light emitting polymer microdiodes, as possible candidates for electrically-driven plastic lasers have been fabricated. Stimulated emission and lasing were also demonstrated for polymer solutions infiltrated in opal photonic crystals. In addition, two unusual regimes of stimulated emission characterized by narrow laser-like spectral lines were found in thin waveguiding polymer films. These regimes may be associated with random optical feedback introduced by light scattering inside the polymer films and amplified Raman scattering, respectively.
MIMO Applicability to UHF SATCOM (2016)

Narrowband satellite communications (SATCOM) in the ultra high frequency (UHF) band is an attractive option within the military SATCOM (MILSATCOM) community. The UHF user terminals (UTs) are typically low cost, easily deployable and have broad beamwidths so that precise pointing to the satellite is not a requirement for mobile users. At the same time, some inherent disadvantages of UHF SATCOM are limited bandwidth, the inability to apply frequency re-use in the geo-stationary arc and hence less capacity. The multiple antenna technique, popularly referred to as MIMO (multiple input multiple output) is known to increase the channel capacity using spatial multiplexing and offers the ability for frequency reuse. The intent of this paper is to analyse the applicability of MIMO to UHF SATCOM, based on some of the recent developments in MIMO SATCOM research. The SATCOM channel is principally dominated by the line of sight (LOS) path between the satellite and the ground user. To achieve spatial orthogonality in the LOS SATCOM channel, depending on the wavelength, antenna separation on the order of several kilometers is required either in space or on the ground. In this paper, we consider using multiple satellites for a large antenna separation in space to enable closer antenna separation for users on the ground. Channel modeling, capacity calculation, issues with the propagation time difference and receiver signal processing are addressed in this paper.
Graphitic Carbon Nitride Nanosheets-Based Ratiometric Fluorescent Probe for Highly Sensitive Detection of H2O2 and Glucose (2016)

Graphitic carbon nitride (g-C<sub>3</sub>N<sub>4</sub>) nanosheets, an emerging graphene-like carbon-based nanomaterial with high fluorescence and large specific surface areas, hold great potential for biosensor applications. Current g-C<sub>3</sub>N<sub>4</sub> nanosheets based fluorescent biosensors majorly rely on single fluorescent intensity reading through fluorescence quenching interactions between the nanosheets and metal ions. Here we report for the first time the development of a novel g-C<sub>3</sub>N<sub>4</sub> nanosheets-based ratiometric fluorescence sensing strategy for highly sensitive detection of H<sub>2</sub>O<sub>2</sub> and glucose. With o-phenylenediamine (OPD) oxidized by H<sub>2</sub>O<sub>2</sub> in the presence of horseradish peroxidase (HRP), the oxidization product can assemble on the g-C<sub>3</sub>N<sub>4</sub> nanosheets through hydrogen bonding and π-π stacking, which effectively quenches the fluorescence of g-C<sub>3</sub>N<sub>4</sub> while delivering a new emission peak. The ratiometric signal variations enable robust and sensitive detection of H<sub>2</sub>O<sub>2</sub>. On the basis of the glucose converting into H<sub>2</sub>O<sub>2</sub> through the catalysis of glucose oxidase, the g-C<sub>3</sub>N<sub>4</sub>-based ratiometric fluorescence sensing platform is also exploited for glucose assay. The developed strategy is demonstrated to give a detection limit of 50 nM for H<sub>2</sub>O<sub>2</sub> and 0.4 μM for glucose, at the same time, it has been successfully used for glucose levels detection in human serum. This strategy may provide a cost-efficient, robust, and high-throughput platform for detecting various species involving H<sub>2</sub>O<sub>2</sub>-generation reactions for biomedical applications.
Fast algorithm for spectral analysis of unevenly sampled data (1989)

The Lomb-Scargle method performs spectral analysis on unevenly sampled data and is known to be a powerful way to find, and test the significance of, weak periodic signals. The method has previously been thought to be 'slow', requiring of order 10(2)N(2) operations to analyze N data points. We show that Fast Fourier Transforms (FFTs) can be used in a novel way to make the computation of order 10(2)N log N. Despite its use of the FFT, the algorithm is in no way equivalent to conventional FFT periodogram analysis.
Deep learning at the edge enables real-time streaming ptychographic imaging (2022)

Coherent microscopy techniques provide an unparalleled multi-scale view of materials across scientific and technological fields, from structural materials to quantum devices, from integrated circuits to biological cells. Driven by the construction of brighter sources and high-rate detectors, coherent X-ray microscopy methods like ptychography are poised to revolutionize nanoscale materials characterization. However, associated significant increases in data and compute needs mean that conventional approaches no longer suffice for recovering sample images in real-time from high-speed coherent imaging experiments. Here, we demonstrate a workflow that leverages artificial intelligence at the edge and high-performance computing to enable real-time inversion on X-ray ptychography data streamed directly from a detector at up to 2 kHz. The proposed AI-enabled workflow eliminates the sampling constraints imposed by traditional ptychography, allowing low dose imaging using orders of magnitude less data than required by traditional methods.
Metastable regulation of type 1 piliation in Escherichia coli and isolation and characterization of a phenotypically stable mutant (1986)

Type 1 piliation in Escherichia coli exhibits phase variation due to the inversion of a small, ca. 300-base-pair, element that regulates pilA (fimA), the gene that encodes the structural subunit of pili (Abraham et al., Proc. Natl. Acad. Sci. USA 82:5724-5727, 1985). We have used the inversion as an assay to characterize a stably piliated mutant. The mutant strain did not exhibit the pilA ON and pilA OFF colonial variants characteristic of the wild type; rather, every clone produced a level of pilA expression intermediate between ON and OFF wild-type populations. The mutant phenotype was conferred by a lesion at a previously undescribed locus between hemA and trpA, which we have termed pilG. Examination of the pilA promoter region in four pilG mutant populations indicated that the phenotypic stability conferred by the pilG mutation was not due to an inability to carry out the inversion. Rather, all pilG mutant populations consisted of approximately equal mixtures of ON and OFF individuals. We suggest that pilG mutants may undergo such rapid switching of the pilA promoter that populations exhibit an intermediate level of pilA expression and phenotypic stability.
Wood-based composite materials for ultralight lens antennas in 6G systems (2022)

Example of square and lens shaped samples made of nanocellulose-glass composite (WNF–HGMS) for 6G antennas. Scale bar: 1 cm.