gebhart/patrepeval huggingface dataset:
Optical Coherence Tomography Imaging in Developmental Biology (2003)

Optical coherence tomography (OCT) is an attractive imaging technique for developmental biology because it permits the imaging of tissue microstructure in situ, yielding micron-scale image resolution without the need for excision of a specimen and tissue processing. OCT enables repeated imaging studies to be performed on the same specimen in order to track developmental changes. OCT is analogous to ultrasound B mode imaging except that it uses low-coherence light rather than sound and performs cross-sectional imaging by measuring the backscattered intensity of light from structures in tissue (1). The principles of OCT imaging are shown schematically in Fig. 1. The OCT image is a gray-scale or false-color two-dimensional (2-D) representation of backscattered light intensity in a cross-sectional plane. The OCT image represents the differential backscattering contrast between different tissue types on a micron scale. Because OCT performs imaging using light, it has a one- to two-order-of-magnitude higher spatial resolution than ultrasound and does not require specimen contact.
Stable simple enols. 31. Substituted xanthenylidene enols. The importance of .beta.-Ar-C:C conjugation in the stabilization of aryl-substituted enols (1992)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStable simple enols. 31. Substituted xanthenylidene enols. The importance of .beta.-Ar-C:C conjugation in the stabilization of aryl-substituted enolsElimelech Rochlin and Zvi RappoportCite this: J. Am. Chem. Soc. 1992, 114, 1, 230–241Publication Date (Print):January 1, 1992Publication History Published online1 May 2002Published inissue 1 January 1992https://pubs.acs.org/doi/10.1021/ja00027a030https://doi.org/10.1021/ja00027a030research-articleACS PublicationsRequest reuse permissionsArticle Views520Altmetric-Citations15LEARN 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-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts
Abnormal Pitch Perception Produced by Cochlear Implant Stimulation (2014)

Contemporary cochlear implants with multiple electrode stimulation can produce good speech perception but poor music perception. Hindered by the lack of a gold standard to quantify electric pitch, relatively little is known about the nature and extent of the electric pitch abnormalities and their impact on cochlear implant performance. Here we overcame this obstacle by comparing acoustic and electric pitch perception in 3 unilateral cochlear-implant subjects who had functionally usable acoustic hearing throughout the audiometric frequency range in the non-implant ear. First, to establish a baseline, we measured and found slightly impaired pure tone frequency discrimination and nearly perfect melody recognition in all 3 subjects' acoustic ear. Second, using pure tones in the acoustic ear to match electric pitch induced by an intra-cochlear electrode, we found that the frequency-electrode function was not only 1-2 octaves lower, but also 2 times more compressed in frequency range than the normal cochlear frequency-place function. Third, we derived frequency difference limens in electric pitch and found that the equivalent electric frequency discrimination was 24 times worse than normal-hearing controls. These 3 abnormalities are likely a result of a combination of broad electric field, distant intra-cochlear electrode placement, and non-uniform spiral ganglion cell distribution and survival, all of which are inherent to the electrode-nerve interface in contemporary cochlear implants. Previous studies emphasized on the "mean" shape of the frequency-electrode function, but the present study indicates that the large "variance" of this function, reflecting poor electric pitch discriminability, is the main factor limiting contemporary cochlear implant performance.
Dynamic Features of a Planetary Gear System With Tooth Crack Under Different Sizes and Inclination Angles (2013)

Planetary gears are widely used in the industry due to their advantages of compactness, high power-to-weight ratios, high efficiency, and so on. However, planetary gears such as that in wind turbine transmissions always operate under dynamic conditions with internal and external load fluctuations, which accelerate the occurrence of gear failures, such as tooth crack, pitting, spalling, wear, scoring, scuffing, etc. As one of these failure modes, gear tooth crack at the tooth root due to tooth bending fatigue or excessive load is investigated; how it influences the dynamic features of planetary gear system is studied. The applied tooth root crack model can simulate the propagation process of the crack along tooth width and crack depth. With this approach, the mesh stiffness of gear pairs in mesh is obtained and incorporated into a planetary gear dynamic model to investigate the effects of the tooth root crack on the planetary gear dynamic responses. Tooth root cracks on the sun gear and on the planet gear are considered, respectively, with different crack sizes and inclination angles. Finally, analysis regarding the influence of tooth root crack on the dynamic responses of the planetary gear system is performed in time and frequency domains, respectively. Moreover, the differences in the dynamic features of the planetary gear between the cases that tooth root crack on the sun gear and on the planet gear are found.
An<i>in vitro</i>blood–brain barrier model: Cocultures between endothelial cells and organotypic brain slice cultures (1998)

This communication describes a novel in vitro blood-brain barrier (BBB) model: organotypic slice cultures from the central nervous system were overlaid on endothelial cell monolayers grown on permeable membranes. Morphological, electrophysiological, and microdialysis approaches were carried out to characterize and validate this model. After 10 days in coculture, morphological studies reveal the presence of tight junctions. Electrophysiological recordings of neuronal activity performed on organotypic cultures with or without an endothelial cell monolayer show that amplitude of evoked responses were comparable, indicating good viability of cocultures after 2 weeks. Perfusion of known BBB permeable or nonpermeable molecules was used to test the coculture tightness in conjunction with electrophysiological or microdialysis approaches: application of glutamate (Glu), which doesn't easily cross the BBB, triggers off rhythmic activity only in control cultures, whereas epileptogenic activity was observed in both control cultures and cocultures during perfusions with picrotoxin, a molecule that can diffuse through the BBB. Finally, the microdialysis technique was used to determine the permeability of molecules coming from the perfusion chamber: L-dopa, dopamine, and Glu were employed to assess the selective permeability of the coculture model. Thus, these results indicate that the in vitro model described possesses characteristics similar to those of the BBB in situ and that cocultures of organotypic slices and endothelial cell monolayers have potential as a powerful tool for studying biochemical mechanisms regulating BBB function and drug delivery to the central nervous system.
Silicon reaction of TiN<i>x</i> diffusion barriers at high temperatures (1991)

TiNx diffusion barriers have been deposited onto n-Si wafers by reactive sputtering in a N2+Ar atmosphere, with a nitrogen content varying in the 0%–25% range. The relative composition of the as-deposited films was examined by Rutherford backscattering spectroscopy (RBS) and Auger electron spectroscopy (AES) analysis yielding a TiNx composition between x=0.8 and x=1.2, respectively. The near stoichiometric samples were thermally annealed at temperatures between 600 and 900 °C in vacuum and N2 atmosphere. Films with composition TiN1.1 and TiN0.9 present very good behavior as barrier layers against the Si diffusion and a very low reactivity with the Si substrate. When the nitrogen content in the as-deposited films decreases, the films lose their barrier properties. For the TiN0.8 samples, Si diffusion through the films is observed after annealing in vacuum at temperatures of 600 °C and above. However, when the heat treatment is carried out in a N2 atmosphere an improvement in the barrier characteristics and reactivity with the Si at the interface was observed.
Analysis of gene expression profile of pancreatic carcinoma using cDNA microarray (2003)

Microarray analysis may provide invaluable information on disease pathology, progression, resistance to treatment, and response to cellular microenvironments of pancreatic carcinoma and ultimately may lead to improving early diagnosis and discovering innovative therapeutic approaches for cancer.
Genetic Engineering of Sexual Sterility in Shade Trees (1998)

Shade trees unable to produce floral tissues, or that produce only nonreproductive floral organs such as petals, are desirable for a number of reasons. They can reduce the need to clean flower and fruit litter, eliminate hazards from large and fleshy fruits on walks, and lessen allergenic pollen production. Research in herbaceous species has established that introduction of gene constructs created by recombinant DNA technology provides an effective means to manipulate flowers without deleterious effects on vegetative growth. Though not yet demonstrated in trees, this approach will likely be successful in both angiosperms and gymnosperms because genes that control reproductive development are similar in sequence and function among diverse plant species. Key to the practical application of genetically engineered sterility to shade trees, however, is the development of efficient gene transfer and vegetative propagation systems to deliver engineered, sterile trees to the marketplace; these systems are in place for a limited number of species. We discuss the rationale for sexual sterility in arboriculture, methods for genetic engineering of sterility, our progress in engineering sterility in poplars, and the current status of transformation and propagation methods for some common shade tree genera.
Distributed and Parallel Simulation in an Interactive Environment. (1995)

Multiprocessing systems are available for a growing number of users, but their exploitation for distributed and parallel simulations is still at the beginning because most today’s engineering software tools do not support distributed and parallel processing. In order to overcome this lack, a general approach to extend interactive environments by the missing features is presented. An interactive Master/Slave-paradigm is introduced, and examples of the main application areas are given.
Nanocrystalline-to-amorphous transition in nanolaminates grown by low temperature atomic layer deposition and related mechanical properties (2012)

We report on a comprehensive structural and nanoindentation study of nanolaminates of Al2O3 and ZnO synthesized by atomic layer deposition (ALD). By reducing the bilayer thickness from 50 nm to below 1 nm, the nanocrystal size could be controlled in the nanolaminate structure. The softer and more compliant response of the multilayers as compared to the single layers of Al2O3 and ZnO is attributed to the structural change from nanocrystalline to amorphous at smaller bilayer thicknesses. It is also shown that ALD is a unique technique for studying the inverse Hall-Petch softening mechanism (E. Voce and D. Tabor, J. Inst. Metals 79(12), 465 (1951)) related to grain size effects in nanomaterials.
Nanoporous Zeolite Thin Film-Based Fiber Intrinsic Fabry-Perot Interferometric Sensor for Detection of Dissolved Organics in Water (2006)

A fiber optic intrinsic Fabry-Perot interferometric (IFPI) chemical sensor wasdeveloped by fine-polishing a thin layer of polycrystalline nanoporous MFI zeolitesynthesized on the cleaved endface of a single mode fiber. The sensor operated bymonitoring the optical thickness changes of the zeolite thin film caused by the adsorption oforganic molecules into the zeolite channels. The optical thickness of the zeolite thin filmwas measured by white light interferometry. Using methanol, 2-propanol, and toluene as themodel chemicals, it was demonstrated that the zeolite IPFI sensor could detect dissolvedorganics in water with high sensitivity.
A Multifactorial Analysis of Melanoma (1978)

A multifactorial analysis was used to identify the dominant prognostic variables affecting survival from a computerized data base of 339 melanoma patients treated at this institution during the past 17 years. Five of the 13 parameters examined simultaneously were found to independently influence five year survival rates: 1) pathological stage (I vs II, p = 0.0014), 2) lesion ulceration (present vs absent, p = 0.006), 3) surgical treatment (wide excision vs wide excision plus lymphadenectomy, p = 0.024), 4) melanoma thickness (p = 0.032), and 5) location (upper extremity vs lower extremity vs trunk vs head and neck, p = 0.038). Additional factors considered that had either indirect or no influence on survival rates were clinical stage of disease, age, sex, level of invasion, pigmentation, lymphocyte infiltration, growth pattern, and regression. Most of these latter variables derived their prognostic value from correlation with melanoma thickness, except sex which correlated with location (extremity lesions were more frequent on females, trunk lesions on males). This statistical analysis enabled us to derive a mathematical equation for predicting an individual patient's probability of five year survival. Three categories of risk were delineated by measuring tumor thickness (Breslow microstaging) in Stage I patients: 1) thin melanomas (<0.76 mm) were associated with localized disease and a 100% cure rate: 2) intermediate thickness melanomas (0.76-4.00 mm) had an increasing risk (up to 80%) of harboring regional and/or distant metastases and 3) thick melanomas (>/=4.00 mm) had a 80% risk of occult distant metastases at the time of initial presentation. The level of invasion (Clark's microstaging) correlated with survival, but was less predictive than measuring tumor thickness. Within each of Clark's Level II, III and IV groups, there were gradations of thickness with statistically different survival rates. Both microstaging methods (Breslow and Clark) were less predictive factors in patients with lymph node or distant metastases. Clinical trials evaluating alternative surgical treatments or adjunctive therapy modalities for melanoma patients should incorporate these parameters into their assessment, especially in Stage I (localized) disease where tumor thickness and the anatomical site of the primary melanoma are dominant prognostic factors.
A rapid-sequential-positioning task for evaluating motion parallax and stereoscopic 3D cues in teleoperator displays (2002)

The first data obtained with a prototype rapid-sequential-positioning (RSP) remote-manipulator task, developed for assessing the effect of various characteristics of teleoperator displays and control systems, are presented. The RSP task requires the operator to move a remote manipulator as quickly as possible to touch, in sequence, ten target sites embedded in a complex wire maze. The data were remarkably consistent across subjects, suggesting that the prototype RSP task can be refined into a standard test instrument for quantitative evaluation of teleoperator displays and manipulator systems.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Estimation of Ocular Rigidity Based on Measurement of Pulse Amplitude Using Pneumotonometry and Fundus Pulse Using Laser Interferometry in Glaucoma (2008)

The present study indicates increased ocular rigidity in patients with POAG. This is compatible with a number of previous animal experiments and supports the concepts that the biomechanical properties of ocular tissues play a role in the diseases process.
Phase Equilibrium in the System Calcite-Aragonite (1953)

The equilibrium curve for two of the phases of CaCO3, calcite-aragonite, has been determined as a function of temperature and pressure over the range 25–80°C and several thousand kg/cm2, using the electrical conductivity of aqueous solutions of each form. Aragonite is proved to be the high pressure modification. From the determined equilibrium curve, various thermodynamic quantities are obtained in a more accurate fashion than previously possible. All normal natural occurrences of aragonite must be due to metastable formation rather than equilibrium, since the geothermal gradient lies completely in the calcite field.
Efficient <sup>18</sup>F-Labeling of Large 37-Amino-Acid pHLIP Peptide Analogues and Their Biological Evaluation (2012)

Solid tumors often develop an acidic microenvironment, which plays a critical role in tumor progression and is associated with increased level of invasion and metastasis. The 37-residue pH (low) insertion peptide (pHLIP) is under study as an imaging platform because of its unique ability to insert into cell membranes at a low extracellular pH (pH(e) < 7). Labeling of peptides with [(18)F]-fluorine is usually performed via prosthetic groups using chemoselective coupling reactions. One of the most successful procedures involves the alkyne-azide copper(I) catalyzed cycloaddition (CuAAC). However, none of the known "click" methods have been applied to peptides as large as pHLIP. We designed a novel prosthetic group and extended the use of the CuAAC "click chemistry" for the simple and efficient (18)F-labeling of large peptides. For the evaluation of this labeling approach, a D-amino acid analogue of WT-pHLIP and an L-amino acid control peptide K-pHLIP, both functionalized at the N-terminus with 6-azidohexanoic acid, were used. The novel 6-[(18)F]fluoro-2-ethynylpyridine prosthetic group, was obtained via nucleophilic substitution on the corresponding bromo-precursor after 10 min at 130 °C with a radiochemical yield of 27.5 ± 6.6% (decay corrected) with high radiochemical purity ≥98%. The subsequent Cu(I)-catalyzed "click" reaction with the azido functionalized pHLIP peptides was quantitative within 5 min at 70 °C in a mixture of water and ethanol using Cu-acetate and sodium L-ascorbate. [(18)F]-D-WT-pHLIP and [(18)F]-L-K-pHLIP were obtained with total radiochemical yields of 5-20% after HPLC purification. The total reaction time was 85 min including formulation. In vitro stability tests revealed high stability of the [(18)F]-D-WT-pHLIP in human and mouse plasma after 120 min, with the parent tracer remaining intact at 65% and 85%, respectively. PET imaging and biodistribution studies in LNCaP and PC-3 xenografted mice with the [(18)F]-D-WT-pHLIP and the negative control [(18)F]-L-K-pHLIP revealed pH-dependent tumor retention. This reliable and efficient protocol promises to be useful for the (18)F-labeling of large peptides such as pHLIP and will accelerate the evaluation of numerous [(18)F]-pHLIP analogues as potential PET tracers.
Circuit Characterization of V-Band IMPATT Oscillators and Amplifiers (1976)

A circuit model has been developed to describe a class of commonly used waveguide cavities for V-band IMPATT oscillators and amplifiers. Calculated results based on this model used in conjunction with theoretical small-signal IMPATT characteristics have shown good qualitative agreement with experimental data. Detailed characterization of a small-signal V-band IMPATT amplifier and a mechanical tuned oscillator are presented, and the predicted performance is compared with measurements.
An algorithm to compute blocking probabilities in multi-rate multi-class multi-resource loss models (1995)

In this paper we consider a family of product-form loss models, including loss networks (or circuit-switched communication networks) and a class of resource-sharing models. There can be multiple classes of requests for multiple resources. Requests arrive according to independent Poisson processes. The requests can be for multiple units in each resource (the multi-rate case, e.g. several circuits on a trunk). There can be upper-limit and guaranteed-minimum sharing policies as well as the standard complete-sharing policy. If all the requirements of a request cannot be met upon arrival, then the request is blocked and lost. We develop an algorithm for computing the (exact) steady-state blocking probability of each class and other steady state descriptions in these loss models. The algorithm is based on numerically inverting generating functions of the normalization constants. In a previous paper we introduced this approach to product-form models and developed a full algorithm for a class of closed queueing networks. The inversion algorithm promises to be even more useful for loss models than for closed queueing networks because fewer alternative algorithms are available for loss models. Indeed, for many loss models with sharing policies other than traditional complete sharing, our algorithm is the first effective algorithm. Unlike some recursive algorithms, our algorithm has a low storage requirement. To treat the loss models here, we derive the generating functions of the normalization constants and develop a new scaling algorithm especially tailored to the loss models. In general, the computational complexity grows exponentially in the number of resources, but the computation can often be reduced dramatically by exploiting conditional decomposition based on special structure and by appropriately truncating large finite sums. We illustrate our numerical inversion algorithm by applying it to several examples. To validate our algorithm on small models, we also develop a direct algorithm. The direct algorithm itself is of interest, because it tends to be more efficient when the number of resources is large, but the number of request classes is small. Furthermore, it also allows a form of conditional decomposition based on special structure.
Design and fabrication of temperature-insensitive InGaP-InGaAlP resonant-cavity light-emitting diodes (2006)

Visible InGaP-InGaAlP resonant-cavity light-emitting diodes with low-temperature sensitivity output characteristics were demonstrated. By means of widening the resonant cavity to a thickness of three wavelength (3/spl lambda/), the degree of power variation between 25 /spl deg/C and 95 /spl deg/C for the devices biased at 20 mA was apparently reduced from -2.1 dB for the standard structure design (1-/spl lambda/ cavity) to -0.6 dB. An output power of 2.4 mW was achieved at 70 mA. The external quantum efficiency achieved a maximum of 3% at 13 mA and dropped slowly with increased current for the device. The external quantum efficiency at 20mA dropped only 14% with elevated temperature from 25 /spl deg/C to 95/spl deg/C. The current dependent far-field patterns also showed that the emission always took place perfectly in the normal direction, which was suitable for plastic fiber data transmission.