gebhart/patrepeval huggingface dataset:
Synthesis and structural transformation of zirconia aerogels (1993)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis and structural transformation of zirconia aerogelsDavid A. Ward and Edmond I. KoCite this: Chem. Mater. 1993, 5, 7, 956–969Publication Date (Print):July 1, 1993Publication History Published online1 May 2002Published inissue 1 July 1993https://pubs.acs.org/doi/10.1021/cm00031a014https://doi.org/10.1021/cm00031a014research-articleACS PublicationsRequest reuse permissionsArticle Views1430Altmetric-Citations167LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Low-k etch/ash for copper dual damascene (2000)

We report the recent progress and issues related to low-k dielectric etch using TEL Unity II tools. Various low-films have been evaluated in terms of etch and post-etch ash. Inorganic and Organo-Silicate Glass films can be etched by modified oxide etch chemistry. In contrast, organic films are etched by non- fluorocarbon chemistry. Although etching the low-k film sis not so difficult, the concern in the damage caused by etch or ash. FTIR, XPS, Secondary Ion Mass Spectroscopy analysis and capacitance measurement suggest that little impact has been induced on the films during etch and properly controlled in-situ ash. Finally, we introduce the dual damascene scheme with spin-on bi-layer hardmask with SiLK.
Synthesis of borophane polymorphs through hydrogenation of borophene (2021)

Synthetic two-dimensional polymorphs of boron, or borophene, have attracted attention because of their anisotropic metallicity, correlated-electron phenomena, and diverse superlattice structures. Although borophene heterostructures have been realized, ordered chemical modification of borophene has not yet been reported. Here, we synthesize "borophane" polymorphs by hydrogenating borophene with atomic hydrogen in ultrahigh vacuum. Through atomic-scale imaging, spectroscopy, and first-principles calculations, the most prevalent borophane polymorph is shown to possess a combination of two-center-two-electron boron-hydrogen and three-center-two-electron boron-hydrogen-boron bonds. Borophane polymorphs are metallic with modified local work functions and can be reversibly returned to pristine borophene through thermal desorption of hydrogen. Hydrogenation also provides chemical passivation because borophane reduces oxidation rates by more than two orders of magnitude after ambient exposure.
The mouse albumin promoter and a distal upstream site are simultaneously DNase I hypersensitive in liver chromatin and bind similar liver-abundant factors in vitro. (1988)

In this paper we characterize the chromatin structure and nuclear proteins associated with different transcriptional states of the mouse serum albumin gene. We found the albumin gene to be transcribed in liver at rates 1000-fold or greater than in other tissues tested. We discovered seven DNase I hypersensitive sites encompassing the albumin gene only in liver chromatin, with strong hypersensitivity at the promoter and the enhancer, which is over 10 kb upstream. Using a gel retardation assay, we found a liver nuclear protein, or set of proteins, which binds specifically to DNA of a liver-specific hypersensitive site that maps 3.5 kb upstream, between the promoter and enhancer. Footprinting, heat insensitivity, and binding competition experiments indicate that the protein(s) have characteristics similar to a heat-stable, liver-abundant protein that binds to the albumin promoter and other enhancer and promoter sequences. Finally, we asked whether the liver-specific factors that cause DNase I hypersensitivity in vivo are present concurrently at the various sites in chromatin. We devised a simple new method to reveal that in liver, individual albumin genes are hypersensitive simultaneously at the promoter, the enhancer, and the -3.5-kb site. Thus, transcriptionally active albumin genes appear to contain tissue-abundant factors that are present at three widely spaced points in chromatin, yet at the same point in time. Similar factors binding simultaneously to at least two of these sites could create a specific structure in chromatin required for high-level albumin gene transcription.
Noninvasive Strategies to Optimise Brain Plasticity: From Basic Research to Clinical Perspectives (2013)

Brain plasticity can be defined as the capacity of cerebral neurons and neural circuits to change, structurally and functionally, in response to experience. This fundamental property is essential for maturation of sensory functions during development, for the adaptability of our behaviour to the environment through learning and memory processes and for brain repair in response to disease and trauma.
Characterization of InGaN/GaN Multiple Quantum Well Nanorods Fabricated by Plasma Etching with Self-Assembled Nickel Metal Nanomasks (2005)

High-density (3.0×10 10 cm -2 ) InGaN/GaN multiple quantum well (MQW) nanorods were fabricated from an as-grown bulk light-emitting diode structure by inductively coupled plasma dry etching with self-assembled nickel metal nanomasks. The self-assembled nickel metal nanomasks were formed by rapid thermal annealing of a nickel metal film at 850°C for 1 min. The influence of the thicknesses of the Ni metal film on the dimensions and density of the nanorods was also investigated. The structural and optical properties of the InGaN/GaN MQW nanorods were established using field emission scanning electron microscopy, transmission electron microscopy and photoluminescence measurements. The diameters and heights of nanorods were estimated to be 60 to 100 nm and more than 0.28 µm, respectively. The peak emission wavelength of the nanorods showed a blue shift of 5.1 nm from that of the as-grown bulk. An enhancement by a factor of 5 in photoluminescence intensity of the nanorods compared with that of the as-grown bulk was observed. The blue shift is attributed to strain relaxation in the wells after dry etching, the quantum confinement effect, or a combination of the two, which results in the enhancement of emission intensity.
Opening the operating window of impulse drying. III, Controlled decompression experiments (1997)

Recent Institute research has shown that changes in the nip-opening process can significantly impact sheet delamination during impulse drying. Empirical evidence shows that by opening the nip to ambient pressures in excess of 1 atm, delamination can be avoided. While this method may prove to be practical, methods that were easier to implement are being sought. Further experimental work showed that by properly controlling the load applied to the sheet as the nip opens, sheet delamination could be inhibited. The experiments identified nip-opening load conditions that were sufficient to suppress the delamination of 205-g/m 2 linerboard handsheets having a freeness of 4009-mL CSF at 35% ingoing solids. Application : this work showed that sheet delamination can be avoided by properly designing the decompression phase of the pressure profile. This can be implemented by modifying the shape of the conventional press shoe or by providing a postnip mechanical load.
Isolation and characterization of a sodium pump inhibitor from human plasma. (1989)

An endogenous sodium pump inhibitor has been purified from human plasma. The purification scheme involved large scale dialysis, extraction of lyophilized dialysate by methanol followed by preparative and semipreparative scale reverse-phase high-performance chromatography. A single peak of biologically active material was obtained enriched by a factor of greater than 10 billion. This material showed high chromatographic polarity, was inactivated by charring, strong acid, or alkali, and was resistant to short-term boiling. The purified material had a molecular weight between 300 and 900 g/mol and was insensitive to type I esterase and a variety of proteolytic enzymes. The purified factor inhibited the ouabain-sensitive uptake of 86Rb by human erythrocytes, binding of [3H]ouabain, and activity of dog kidney Na,K-adenosine triphosphatase (ATPase) with high affinity (less than 0.3 nM) in a time- and dose-dependent manner. Maximally effective concentrations of the digitalislike factor showed no effect on either human red blood cell Mg- or Ca-ATPase, rabbit muscle sarcoplasmic reticulum Ca-ATPase, or guinea pig stomach H,K-ATPase. The purified material is a highly potent selective inhibitor of the ion transport, receptor, and hydrolytic functions of the sodium pump. The characteristic properties of this substance suggest it may be a mammalian endogenous digitalis and may be similar to the sodium transport inhibitor detected in the plasma of volume-sensitive forms of experimental and human hypertension.
<b>A class of gyrase mutants of <i>Salmonella typhimurium</i> show quinolone‐like lethality and require Rec functions for viability</b> (1996)

We have identified a new class of DNA gyrase mutants of Salmonella typhimurium that show chronic derepression of the SOS regulon. Thus, these mutants mimic the response of wild-type cells to gyrase inhibitors of the quinolone family. SOS induction by conditional lethal mutations gyrA208 or gyrB652, like that mediated by quinolones, is completely dependent on the function of the recB gene product. Introduction of recA or recB null mutations into these strains exacerbates their temperature-sensitive phenotype and prevents growth at the otherwise permissive temperature of 37 degrees C. Selection of suppressors that concomitantly restore growth at 37 degrees C and SOS induction in a recB- background yielded mutations that relleve the RecB requirement for homologous recombination; namely, sbcB mutations as well as mutations at a new locus that was named sbcE. Such mutations also restore SOS induction in quinolone-treated gyr+ recB- strains. These findings indicate that Rec functions are needed for growth of the gyrase mutants at 37 degrees C and suggest that recombinational repair intermediates constitute the SOS-inducing signal in the mutants as well as in quinolone-treated wild-type bacteria. Unlike quinolones, however, the gyr mutations described in this study do not cause detectable accumulation of "cleavable' gyrase-DNA complexes in plasmid or chromosomal DNA. Yet gyrA208 (the only allele tested) was found to trigger RecB-mediated reckless degradation of chromosomal DNA in recA-cells at restrictive temperatures. Indirect evidence suggests that double-stranded DNA ends, entry sites for the RecBCD enzyme, are generated in the gyr mutants by the breakage of DNA-replication forks. We discuss how this could occur and how recombinational rescue of collapsed replication forks could account for cell survival (and SOS induction) in the gyr mutants as well as in quinolone-treated bacteria.
High-energy (λ≲7300 Å) 300 K operation of single- and multiple-stripe quantum-well heterostructure laser diodes in an external grating cavity (1984)

A set of high performance single- and multiple-stripe Alx′Ga1−x′As -AlxGa1−xAs quantum-well heterostructure (QWH) laser diodes coupled to an external grating cavity is used to demonstrate the tuning properties of a semiconductor laser at short wavelength (λ≲7300 Å). A single-stripe laser diode (6-μm stripe width) with a single AlxGa1−xAs (x∼0.22) quantum well of size Lz≊400 Å is broadly tunable (7080≤λ≤7370 Å, Δℏω∼70 meV) and delivers a single dominant longitudinal mode of moderate output power (Pout∼50 mW at 200 mA, pulsed). In continuous (cw) operation (I=135 mA) a single-stripe laser has a 36-meV tuning range, 7168≤λ≤7322 Å. Phase-locked twenty- and forty-stripe diodes (3.5-μm stripe width) from the same QWH wafer are capable of single-longitudinal-mode output at higher power (peak Pout∼1.6 W at a 8.0-A, 200-ns pulse) although at slightly longer wavelength and reduced tuning range (7225≤λ≤7425 Å). Data are presented illustrating the wavelength dependence of the gain and power output as well as the partial homogeneous broadening and phase-locked nature of the QWH laser arrays. The difference in performance of the multiple-stripe diodes compared with the single-stripe structure can be attributed to the internal coupling of the optical field in neighboring stripes and the reduced threshold current density.
Co-iOAM: In-situ telemetry metadata transport for resource constrained networks within IETF standards framework (2018)

Providing reliable and continuous wireless connectivity during the operational phase of large-scale IoT deployments is a challenge for network operators. Conventional methods of acquiring network telemetry data using dedicated probe messages are costly in terms of additional bandwidth consumption, battery depletion, increased network congestion, leading to degraded application QoS. We propose an in-situ network telemetry transport mechanism, termed Co-iOAM (Telemetry in-situ Operations Administration and Maintenance), for monitoring and troubleshooting resource constrained 6LoWPAN/LPWAN networks, where telemetry data appended as metadata accompanying application packet at intermediate nodes. Further, cross-layer telemetry information support by Co-iOAM can be used for performance analysis of the path traversed by the application packets, network lifetime estimation, and network planning. The architectural and design objectives of Co-iOAM include, flexibility, light-weight operation, and cross-layer telemetry data and its optimized representation. We share the implementation aspects of the protocol on Contiki OS, and present the experimental results that exhibit relatively good scalability. We also propose context aware compression and simple distributed probabilistic update techniques to further reduce the byte overheads of Co-iOAM data while maintaining the quality of network monitoring.
High-Energy-Resolution Microcalorimeter Spectrometer for EDS X-ray Micro Analysis (1997)

Abstract Si(Li) and Ge Energy Dispersive Spectroscopy (EDS) detectors are commonly used for x-ray microanalysis because they are easy to use, inexpensive to operate, and offer both rapid qualitative evaluation of chemical composition and accurate quantitative analysis. Unfortunately, they are limited by energy resolutions on the order of 100 eV, which is insufficient to resolve many important overlapping x-ray peaks in materials of industrial interest, such as the Si Kα and W Mα peak overlap in WSi2. Although WDS spectrometers with excellent energy resolution (typically 2 eV to 10 eV) can resolve most peak overlaps, qualitative WDS analysis is limited by the need to serially scan over the entire energy range using multiple diffraction crystals. There is a need for a new generation of x-ray spectrometers for microanalysis that combines the excellent energy resolution of WDS spectrometers with the ease of use and the parallel energy detection capability of EDS spectrometers. We are developing a high-energy-resolution x-ray microcalorimeter spectrometer for use in x-ray microanalysis. Our microcalorimeter spectrometer consists of a superconducting transition-edge microcalorimeter cooled to an operating temperature of 100 mK by a compact adiabatic demagnetization refrigerator mounted on a SEM column, read-out SQUID (Superconducting Quantum Interference Device) electronics followed by pulse-shaping amplifiers and pile-up rejection circuitry, and a multichannel analyzer with real-time computer interface.
A game-theoretic framework for robot motion planning (1996)

The primary contribution of this dissertation is the presentation of a dynamic game-theoretic framework that is used as an analytical tool and unifying perspective for a wide class of problems in robot motion planning. The framework provides a precise mathematical characterization that can incorporate any of the essential features of decision theory, stochastic optimal control, and traditional multiplayer games. The determination of strategies that optimize some precise performance functionals is central to these subjects, and is of fundamental value for many types of motion planning problems.
The basic motion planning problem is to compute a collision-free trajectory for the robot, given perfect sensing, an exact representation of the environment, and completely predictable execution. The best-known algorithms have exponential complexity, and most extensions to the basic problem are provably intractable. The techniques in this dissertation characterize several extensions to the basic motion planning problem, and lead to computational techniques that provide practical, approximate solutions. A general perspective on motion planning is also provided by relating the similarities between various extensions to the basic problem within a common mathematical framework.
Modeling, analysis, algorithms, and computed examples are presented for each of three problems: (1) motion planning under uncertainty in sensing and control; (2) motion planning under environment uncertainties; and (3) multiple-robot motion planning. Traditional approaches to the first problem are often based on a methodology known as preimage planning, which involves worst-case analysis. In this context, a general method for determining feedback strategies is developed by blending ideas from stochastic optimal control and dynamic game theory with traditional preimage planning concepts. This generalizes classical preimages to performance preimages and preimage plans to motion strategies with information feedback. For the second problem, robot strategies are analyzed and determined for situations in which the environment of the robot is changing, but not completely predictable. Several new applications are identified for this context. The changing environment is treated in a flexible manner by combining traditional configuration space concepts with stochastic optimal control concepts. For the third problem, dynamic game-theoretic and multiobjective optimization concepts are applied to motion planning for multiple robots. This allows the synthesis of motion plans that simultaneously optimize an independent performance criterion for each robot. Several versions of the formulation are considered: fixed-path coordination, coordination on independent configuration-space roadmaps, and centralized planning.
Development of a pen-shaped scanner and its applications (1999)

A truly portable scanner would add another dimension to mobile computing. Using the compact optical configuration single optical fiber imaging (SOFI), a handheld scanner can be built inside a penshaped housing. Here, an image sensor formed on a glass substrate is used. Each photodiode of the image sensor has multiple apertures coupled to multiple optical fibers. The light is transmitted through the glass, the apertures and the fibers successively, and a document is illuminated. Scattered light comes back in the same fibers and is detected by a sensitive part of the photodiode. Therefore, a single fiber is involved to both illuminate the document and detect the reflected light. By incorporating light-absorbing material at the fiber boundaries, optical crosstalk inside the fiber array is suppressed. The design of this SOFI-based scanner is studied in detail. A prototype is developed: the width of its housing and the input length are 13 and 110 mm, respectively. The key components are an image sensor fabricated by a-Si and poly-Si thin film technology, a 2 mm-thick array of optical fibers with 0.9 numerical aperture, and an array of three-color LEDs. Images of color documents and fingerprints are successfully acquired by this scanner.
Element selection from a fuzzy subset using the fuzzy integral (1993)

The problem of selecting a crisp element based upon a fuzzy set is investigated. It is noted that the defuzzification problem in fuzzy logic control is a special case of this problem. The given fuzzy subset is considered as a set of pieces of advice where the strengths of the advice is the membership grade. This problem is formulated in terms of a generalized expected value, an aggregation problem, by using the fuzzy integral. Ways to convert the fuzzy set into a fuzzy measure are shown. Different structures for the calculation of best action are developed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Influence of ocular chromatic aberration and pupil size on transverse resolution in ophthalmic adaptive optics optical coherence tomography (2005)

Optical coherence tomography (OCT) enables visualization of the living human retina with unprecedented high axial resolution. The transverse resolution of existing OCT approaches is relatively modest as compared to other retinal imaging techniques. In this context, the use of adaptive optics (AO) to correct for ocular aberrations in combination with OCT has recently been demonstrated to notably increase the transverse resolution of the retinal OCT tomograms. AO is required when imaging is performed through moderate and large pupil sizes. A fundamental difference of OCT as compared to other imaging techniques is the demand of polychromatic light to accomplish high axial resolution. In ophthalmic OCT applications, the performance is therefore also limited by ocular chromatic aberrations. In the current work, the effects of chromatic and monochromatic ocular aberrations on the quality of retinal OCT tomograms, especially concerning transverse resolution, sensitivity and contrast, are theoretically studied and characterized. The repercussion of the chosen spectral bandwidth and pupil size on the final transverse resolution of OCT tomograms is quantitatively examined. It is found that losses in the intensity of OCT images obtained with monochromatic aberration correction can be up to 80 %, using a pupil size of 8 mm diameter in combination with a spectral bandwidth of 120 nm full width at half maximum for AO ultrahigh resolution OCT. The limits to the performance of AO for correction of monochromatic aberrations in OCT are established. The reduction of the detected signal and the resulting transverse resolution caused by chromatic aberration of the human eye is found to be strongly dependent on the employed bandwidth and pupil size. Comparison of theoretical results with experimental findings obtained in living human eyes is also provided.
Tetravalent manganese in lithium-doped MgO and CaO (1976)

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Experience with central venous access devices (<scp>CVAD</scp>s) in the Canadian hemophilia primary prophylaxis study (<scp>CHPS</scp>) (2015)

Our study shows that the CHPS tailored prophylaxis regimen is associated with a decreased requirement for CVADs and with few device-related complications.