gebhart/patrepeval huggingface dataset:
Structural and Rheological Properties of Hydrophobically Modified Polysaccharide Associative Networks (2004)

The phase behavior of hydrophobically modified chitosans (HMCs) in aqueous solution has been investigated using scattering and rheology experiments. We observed four regions on the phase diagram of the associative polymer: (i) a supernatant phase (unimers phase) at low polymer concentration; (ii) a dilute solution of intermolecularly bridged flowerlike micelles at intermediate concentration; (iii) an associative gel phase at high polymer content; and (iv) a phase separation. In the present paper, we discuss the structural and dynamical properties of the HMC associative networks (c > c*) at a fixed hydrophobic degree of substitution of 2% and fixed alkyl side chains (stickers) length C8 (domains iii and iv of the phase diagram). As the polymer concentration is increasing, a connecting network is formed from the percolation of bridges between micellar aggregates. In this regime, small-angle neutron scattering and light scattering measurements show that -50-nm flower aggregates are acting like junction points in the network. The effect of the concentration, the stress, and the shear on the structure of the network is discussed. In particular, we observe bridge-to-loop transitions and then the formation of microgels or a low-connected network under shear. Therefore, our results are compared to recent theoretical models and to the results reported for telechelic systems.
Caloric restriction increases neurotrophic factor levels and attenuates neurochemical and behavioral deficits in a primate model of Parkinson's disease (2004)

We report that a low-calorie diet can lessen the severity of neurochemical deficits and motor dysfunction in a primate model of Parkinson's disease. Adult male rhesus monkeys were maintained for 6 months on a reduced-calorie diet [30% caloric restriction (CR)] or an ad libitum control diet after which they were subjected to treatment with a neurotoxin to produce a hemiparkinson condition. After neurotoxin treatment, CR monkeys exhibited significantly higher levels of locomotor activity compared with control monkeys as well as higher levels of dopamine (DA) and DA metabolites in the striatal region. Increased survival of DA neurons in the substantia nigra and improved manual dexterity were noted but did not reach statistical significance. Levels of glial cell line-derived neurotrophic factor, which is known to promote the survival of DA neurons, were increased significantly in the caudate nucleus of CR monkeys, suggesting a role for glial cell line-derived neurotrophic factor in the anti-Parkinson's disease effect of the low-calorie diet.
Photoinduced poling of lead titanate zirconate thin films (1997)

The influence of ultraviolet (UV) illumination on piezoelectric properties is investigated in lead zirconate titanate (PZT) thin films. It is found that the poling procedure is more effective when the film is exposed to a broadband UV light in the presence of a high electric field. Piezoelectric coefficients are increased and aging rates are decreased as compared to poling in dark conditions. Both an internal bias field and a polarization offset are observed in the piezoelectric hysteresis loops. The mechanism of the photoinduced poling effect in PZT films is probably due to electron trapping near the film-electrode interface.
A Highly Scalable Capacitorless Double Gate Quantum Well Single Transistor DRAM: 1T-QW DRAM (2008)

We propose a new kind of capacitorless DRAM: 1Transistor Quantum Well structure, which has a ldquostorage pocketrdquo for holes within the body. This memory gives the opportunity to engineer spatial hole distribution within the body of the device, which is not possible with the conventional 1T-DRAMs. Using this novel device, we demonstrate approximately two order-of-magnitude increase in the drain-current ( <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Id</i> ) difference between the reads of two states of the memory.
A Bio-Bar-Code Assay Based upon Dithiothreitol-Induced Oligonucleotide Release (2005)

The recently developed bio-bar-code assay for the PCR-less detection of protein and nucleic acid targets has been shown to be extraordinarily sensitive, exhibiting low attomolar sensitivity for protein targets and high zeptomolar sensitivity for nucleic acid targets. In the case of DNA detection, the original assay relies on three distinct oligonucleotide strands on a single nanoparticle for target identification and signal amplification. Herein, we report the development of a new nanoparticle probe that can be used in the bio-bar-code assay, which requires only one thiolated oligonucleotide strand. This new assay relies on the ability to liberate the adsorbed thiolated oligonucleotides from the gold nanoparticle surface with dithiothreitol (DTT), which simplifies the assay and increases its quantitative capabilities. The utility of this new DTT-based system is demonstrated by detecting a mock mRNA target using both fluorescent and scanometric assay readouts. When the scanometric readout is used, the sensitivity of the assay is 7 aM and quantification can be accomplished over the low-attomolar to the mid-femtomolar concentration range.
Digital image restoration (1997)

The article introduces digital image restoration to the reader who is just beginning in this field, and provides a review and analysis for the reader who may already be well-versed in image restoration. The perspective on the topic is one that comes primarily from work done in the field of signal processing. Thus, many of the techniques and works cited relate to classical signal processing approaches to estimation theory, filtering, and numerical analysis. In particular, the emphasis is placed primarily on digital image restoration algorithms that grow out of an area known as "regularized least squares" methods. It should be noted, however, that digital image restoration is a very broad field, as we discuss, and thus contains many other successful approaches that have been developed from different perspectives, such as optics, astronomy, and medical imaging, just to name a few. In the process of reviewing this topic, we address a number of very important issues in this field that are not typically discussed in the technical literature.
Induced Stress Diversion: A Novel Approach to Fracturing Multiple Pay Sands of the NBU Field, Uintah Co., Utah (1998)

Abstract This paper presents results of utilizing "Induced Stress Diversion" (ISD) to fracture stimulate multiple pay sands in the Natural Buttes Field of Uintah County, Utah. Historically, these multiple pay sands have been stimulated with the Limited Entry technique. To a lesser degree, some wells have been stimulated in stages using positive isolation. The decision to try "Induced Stress Diversion" (ISD) was made to combine the economies of the limited entry technique with the superior production results expected of a staged completion. The technique involves pumping multiple flacs in a well relying on the Induced Stress imparted by the first fracture stimulation to divert the subsequent frac into the desired zone (i.e. no positive isolation). The ISD technique has worked well in many instances to date. This is especially notable because the majority of wells thus far have been done without consistent attempts to close the fracture prior to commencing the next fracture stage. To allow the technique to have wider application, emphasis is currently directed at improved methods of inducing screenout. Based on initial results, the technique appears to have wide application and could improve the economics of developing multiple-pay reservoirs. P. 375
Location services using cellular digital packet data (2002)

This paper presents how a standard mobile data technology, cellular digital packet data (CDPD) can be used to provide a location service. The location service considered is a means of locating mobiles as and when they move (on land) from one point to another. This kind of service is very useful in applications such as fleet management for road transport, emergency services and dynamic route guidance. The location service provided as a part of the CDPD standards enable mobiles to be located with an accuracy of a cell size which is of the order of a few kilometers. The paper also presents an alternative approach for providing a location service by integrating the CDPD data service with a standard positioning system, such as GPS, for locating mobiles with a precision of about 100 meters.
Pattern Discovery Techniques for Music Audio (2002)

Human listeners are able to recognize structure in music through the perception of repetition and other relationships within a piece of music. This work aims to automate the task of music analysis. Music is “explained” in terms of embedded relationships, especially repetition of segments or phrases. The steps in this process are the transcription of audio into a representation with a similarity or distance metric, the search for similar segments, forming clusters of similar segments, and explaining music in terms of these clusters. Several transcription methods are considered: monophonic pitch estimation, chroma (spectral) representation, and polyphonic transcription followed by harmonic analysis. Also, several algorithms that search for similar segments are described. These techniques can be used to perform an analysis of musical structure, as illustrated by examples.
An in vitro Model of Human Dental Pulp Repair (1996)

Pulp tissue responds to dentin injury by laying down reactionary dentin secreted by existing odontoblasts or reparative dentin elaborated by odontoblast-like cells that differentiated from precursor cells in the absence of inner dental epithelium and basement membrane. Furthermore, growth factors or active dentin matrix components are fundamental signals involved in odontoblast differentiation. In vitro, dental pulp cells cultured under various conditions are able to express typical markers of differentiation, but no culture system can re-create pulp response to dentin drilling. This paper reports the behavior of thick slices from human teeth drilled immediately after extraction and cultured from 3 days to 1 month. Results show that the damaged pulp beneath the cavity is able to develop, in vitro, some typical aspects correlated to tissue healing, evidenced by cell proliferation (BrdU-positive cells), neovascularization (positive with antitype-IV collagen antibodies), and the presence of functional (3H proline-positive) cuboidal cells close to the injured area. After 30 days of culture, elongated spindle-shaped cells can be seen aligned along the edges of the relevant dentin walls, whereas sound functional odontoblasts are well-preserved beneath healthy areas. This tissue recovery leads us to believe that such a culture model will be a useful system for testing factors regulating pulp repair.
7-Oxabicycloheptylprostanoic acids: potent, time-dependent cyclooxygenase inhibitors that induce a conformational change in the prostaglandin endoperoxide synthase protein (1992)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXT7-Oxabicycloheptylprostanoic acids: potent, time-dependent cyclooxygenase inhibitors that induce a conformational change in the prostaglandin endoperoxide synthase proteinIndrani Pal, Rebecca Odenwaller, and Lawrence J. MarnettCite this: J. Med. Chem. 1992, 35, 12, 2340–2342Publication Date (Print):June 1, 1992Publication History Published online1 May 2002Published inissue 1 June 1992https://pubs.acs.org/doi/10.1021/jm00090a026https://doi.org/10.1021/jm00090a026research-articleACS PublicationsRequest reuse permissionsArticle Views37Altmetric-Citations4LEARN 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
Timing recovery for OFDM transmission (2000)

Orthogonal frequency division multiplexing (OFDM) is an effective modulation technique for high-rate and high-speed transmission over frequency selective fading channels. However, OFDM systems can be extremely sensitive and vulnerable to synchronization errors. In this paper, we present a scheme for performing timing recovery that includes symbol synchronization and sampling clock synchronization in OFDM systems. The scheme is based on pilot subcarriers. In the scheme, we use a path time delay estimation method to improve the accuracy of the correlation-based symbol synchronization methods, and use a delay-locked loop (DLL) to do the sampling clock synchronization. It is shown that by using this scheme, the mean square values of the symbol timing estimation error can be decreased by several orders of magnitude compared to the common correlation methods in both the AWGN and multipath fading channels. In addition, the scheme can track the symbol timing drift caused by the sampling clock frequency offsets.
Transforming growth factor β decreases the rate of proliferation of rat vascular smooth muscle cells by extending the G2 phase of the cell cycle and delays the rise in cyclic AMP before entry into M phase (1994)

Transforming growth factor beta 1 (TGF-beta 1) decreased the rate of proliferation of rat aortic vascular smooth muscle cells (VSMCs) stimulated with serum showing a maximal effect at > 5 ng/ml (200 pM). However, it did not reduce the proportion of cells which passed through S phase (> 90%) and entry into S phase was delayed by less than 3 h. The proportion of cells passing through M phase (> 90%) was also unaffected, but entry into mitosis was delayed by approx. 24 h. This increase in cell cycle time was therefore due mainly to an increase in the G2 to mitotic metaphase period. Addition of TGF-beta 1 late in G1 or late in S phase failed to delay the onset of mitosis, but the presence of TGF-beta 1 between 0 and 12 h after the addition of serum to quiescent cells was sufficient to cause the maximal delay in mitosis of approx. 24 h. The role of cyclic AMP in the mechanism of the TGF-beta 1 effects on the cell cycle was examined. Entry into mitosis was preceded by a transient 2-fold increase in cyclic AMP concentration and TGF-beta 1 delayed both this increase in cyclic AMP and entry into mitosis to the same extent. Addition of forskolin or 8-(4-chlorophenylthio)-cyclic AMP to cells 30 h after stimulation with serum completely reversed the increase in duration of G2 in the presence of TGF-beta 1, suggesting that the rise in cyclic AMP levels which precedes mitosis might trigger entry of the VSMCs into M phase. Addition of forskolin late in S phase (26 h after stimulation with serum) advanced the entry of the cells into M phase and they divided prematurely. This effect was unaffected by the addition of cycloheximide with the forskolin; however, the effect of forskolin on cell division was completely inhibited when cycloheximide was added late in G1. TGF-beta 1 prevented the loss of smooth-muscle-specific myosin heavy chain (SM-MHC), which occurs in primary VSMC cultures in the presence or absence of serum, and the cells proliferated while maintaining a differentiated phenotype. However, TGF-beta 1 did not cause re-differentiation of subcultured VSMCs which contained very low amounts of SM-MHC and the effect of TGF-beta 1 in extending the G2 phase of the cell cycle is exerted independently of its effect on differentiation.
DNA-mediated engineering of multicomponent enzyme crystals (2015)

The ability to predictably control the coassembly of multiple nanoscale building blocks, especially those with disparate chemical and physical properties such as biomolecules and inorganic nanoparticles, has far-reaching implications in catalysis, sensing, and photonics, but a generalizable strategy for engineering specific contacts between these particles is an outstanding challenge. This is especially true in the case of proteins, where the types of possible interparticle interactions are numerous, diverse, and complex. Herein, we explore the concept of trading protein-protein interactions for DNA-DNA interactions to direct the assembly of two nucleic-acid-functionalized proteins with distinct surface chemistries into six unique lattices composed of catalytically active proteins, or of a combination of proteins and DNA-modified gold nanoparticles. The programmable nature of DNA-DNA interactions used in this strategy allows us to control the lattice symmetries and unit cell constants, as well as the compositions and habit, of the resulting crystals. This study provides a potentially generalizable strategy for constructing a unique class of materials that take advantage of the diverse morphologies, surface chemistries, and functionalities of proteins for assembling functional crystalline materials.
Protection from Rotavirus Reinfection: 2-Year Prospective Study (1991)

To measure protection induced by natural rotavirus infection, 163 infants enrolled in a rotavirus vaccine trial were prospectively followed for 2 years. Serotype 1 rotaviruses were the predominant circulating strains during the study. Over the 2 years of observation, significantly fewer infants infected before enrollment developed a symptomatic reinfection (0 of 21) or any reinfection (4 of 21) compared with previously uninfected infants (P = .0003). Of the 60 infants who developed a primary rotavirus infection in the first year (40 symptomatic, 20 asymptomatic) only 4 were reinfected in the second year compared with 29 of 82 subjects not previously infected (P = .00003). Asymptomatic primary infection appeared to be as protective as symptomatic primary infection. The only symptomatic reinfections occurred in 2 subjects who did not develop rotavirus antibody after the initial detection of rotavirus. An age-related reduction in the ratio of symptomatic to asymptomatic primary rotavirus infection was also detected. In this study, protection against homotypic serotype 1 reinfection appeared to last greater than or equal to 2 years.
A comparison of estimates of statewide pleasure trip volume and expenditures derived from telephone versus mail surveys (1998)

This paper compares estimates of pleasure trip volume and expenditures derived from a regional telephone survey to those derived from the TravelScope mail panel survey. Significantly different estimates emerged, suggesting that survey-based estimates of pleasure trip volume and expenditures, at least in the case of the two surveys examined, appear to be affected by methods of data collection. This in turn suggests that caution should be exercised in using such estimates to make important decisions in the tourism industry.
Understanding Irreversible Capacity in Li[sub x]Ni[sub 1−y]Fe[sub y]O[sub 2] Cathode Materials (2000)

A study was made of lithium‐ion cell cathode materials. Through a series of experiments including cyclic voltammetry, X‐ray diffractometry, Mössbauer spectroscopy, in situ X‐ray diffractometry, and in situ Mössbauer spectroscopy, it was determined that the phenomenon commonly referred to as "irreversible capacity" in lithium‐ion cell cathode materials is a misnomer. Cells utilizing with 0.05 ≤ y ≤ 0.10 as the cathode active material (vs. a lithium metal anode) have been reversibly cycled between 0.64 ≤ x ≤ 1.00 (100 mAh/g). The recovery of the "irreversible capacity" involved a discharge through a ∼2 V plateau during which it is believed that a surface layer of is present. Also, a new transition has been observed between two O3 phases (belonging to the space group ) during charge beginning at the start of charge and reaching completion by x ≈ 0.82 (50 mAh/g). The cause of this transition as well as the formation of the surface layer during discharge are explained in terms of the mobility of lithium ions in the intercalation host being related to the availability of monovacancy and divacancy hopping paths. © 2000 The Electrochemical Society. All rights reserved.
Design of an Aberration-Free Spherical Micro Lens with a Diffractive Relief Grating Film on a Refractive Spherical Glass Substrate (1992)

A combined micro-objective lens for optical disc use has been developed. The lens consists of a thin relief diffraction grating film and a planoconvex glass substrate. The combined lens, which is called the spherical grating lens (SGL), is inherently a spherical lens, but has some interesting features such as high numerical aperture and “spherical aberration”-free. The aberration in the refractive substrate is canceled by a thin diffraction grating film. This paper shows the ray tracing design of the SGL and the calculation results, and finally, the experimental results show that the SGL can he used as a low-cost objective lens in the optical disc head if it is appropriately designed.
Functional role of heme ligation in cytochrome c. Effects of replacement of methionine 80 with natural and non-natural residues by semisynthesis. (1992)

The nature of the axial ligation to heme iron has been suggested to be the major determinant of the oxidation-reduction potential of a particular cytochrome, but natural cytochromes that vary significantly in E'm invariably differ from one another in many ways. We proposed to clarify this issue by engineering many different ligation patterns within the same basic molecule, mitochondrial cytochrome c. Since many of the potentially informative substitutions require non-coded amino acids, semisynthesis was the approach we chose, and solid-phase peptide synthesis was used to make a set of nin 39-residue peptides that have been incorporated by autocatalytic fragment religation into the structure of horse cytochrome c. An additional two analogues modified at this position were made by chemical modification of the whole protein. As well as looking at the effect on reduction potential, we examined the effect of varying the ligand sphere on the efficiency of the autocatalytic fragment religation reaction, on the conformation of cytochrome c, on its spectroscopic properties, and in promoting electron transfer between heme c and other redox centers. Substitute residues were chosen to put sulfur, selenium, oxygen, and nitrogen, or even no ligating atom at all in the place of methionine sulfur. We found both subtle and dramatic alterations in spectral properties, which were informative about changes in internal structure and stability brought about by the modifications and which may be useful in identifying novel natural ligation patterns. An unexpected finding was that alanine 80 cytochrome c acquires a hemoglobin-like spectrum, and binds O2 most effectively. Reduction potential changes of greater than 300 mV with nitrogen, greater than 400 mV with oxygen, and greater than 300 mV with thiol sulfur ligation were observed, confirming that variation of the ligand sphere is indeed the most effective way in which the protein coat may modulate the potential of the redox center it encloses. Finally, we obtained more evidence that this axial ligand plays an active role in electron transfer and discovered that histidine could be even more effective in this role.