gebhart/patrepeval huggingface dataset:
Mechanical Rejuvenation in Poly(methyl methacrylate) Glasses? Molecular Mobility after Deformation (2010)

Optical photobleaching experiments were used to directly measure the molecular mobility of PMMA during creep and recovery to study the interaction between mechanical deformation and physical aging. Experiments were performed both on PMMA glasses with different aging histories at Tg − 14 K and on PMMA melts aged to equilibrium as much as 6 K below the conventional DSC Tg. Our results show that plastic deformation increases the mobility of a polymer glass, makes the system more dynamically homogeneous, and erases the predeformation aging history. After removing the stress, the highly mobile and dynamically homogeneous system quickly relaxes to a dynamically heterogeneous system. After this initial transient, glasses produced by plastic deformation follow the same aging trajectory of the thermally quenched glasses unless the strain is very large. In contrast, deformation in the preflow regime transiently increases the molecular mobility of polymer glasses but this enhanced mobility quickly returns to the original aging trajectory after unloading the stress, indicating that preflow deformation does not change the “age” of the polymer.
Modeling on phosphor sedimentation phenomenon during curing process of high power LED packaging (2014)

Abstract In the LED packaging, the phosphor particles are usually mixed with silicone matrix material, and then dispensed onto the LED chips directly. Since the density of the phosphor particle is bigger than that of the silicone, the phosphor particles may settle in the silicone matrix because of the gravity during dispensing and curing processes. In this paper, a model was developed to investigate the phosphor sedimentation phenomenon in silicone during isothermal curing according to the Stokes’ law, and the size distribution of phosphor particles and the viscosity-time function of silicone during curing were built for the model. We compared the modeling results with the experimental results and found that the model can well simulate the sedimentation phenomenon. The modeling results show that the sedimentation velocity is inversely proportional to the viscosity of silicone and proportional to the size of phosphor particle. Phosphor particles sedimentation lasts for about 5 minutes during isothermal curing at 85°C, and the big particles accumulate in the bottom of the sample.
Higher Resolution Seismic Imaging using Holography (2010)

Holographic Imaging of the earth subsurface using seismic survey data produces substantially greater spatial and time resolution than may be obtained by traditional signal processing methods. For this reason such imaging is often called “Highest Possible Resolution” or “High Definition” Imaging. This new Paradigm for holistic seismic imaging is based on waveform interference patterns. Migration as we know it is wave‐based and attempts to reconstruct wavefields at any point within the earth using approximations to the wave equation. The reconstructed wavefield is a migrated section. In our case, it is important to distinguish between wavefield reconstruction and the imaging process. Wavefield reconstruction is the determination of the wavefield over an area of interest. Imaging on the other hand, creates a picture of the reflecting surfaces within an area of interest. The input to the migration process is the seismic data, sometimes referred to as a hologram. This takes into account all the recorded signals received at the earth's surface. The first step of migration process is wavefield reconstruction. The second step is imaging. Attainable resolution using Holographic Imaging techniques represents the highest possible values with limits imposed by the imaging approximations, estimated propagation velocities, noise, and the geologic character. Such character relates to the sediment deposition and its energy, having specific expression in terms of variations over the effective Fresnel Zone and vertical grading or transitioning of the lithologies. For such imaging, as typical of Holographic methods, illumination bandwidth is largely incidental, and frequencies in the image domain may range between 3 and 10 times the usual input bandwidths, and possibly greater, as geology ultimately permits. This paper presents advantages and merits of Holographic Imaging by examples and comparisons supported by the modeling. One of the other advantages in having broader bandwidths for both frequency and wavenumber is seen in the detailed velocity analyses. High density and high definition velocity analyses enables one after imaging, to see subtle stratigaphic details and fault planes and also in the deeper seismic data, making it easier and even practical to interpret the tectonic style and stratigraphy.
A combined MMSE-ML detection for a spectrally efficient non orthogonal FDM signal (2008)

In this paper, we investigate the possibility of reliable and computationally efficient detection for spectrally efficient non-orthogonal Multiplexing (FDM) system, exhibiting varying levels of intercarrier interference. Optimum detection is based on the Maximum Likelihood (ML) principle. However, ML is impractical due to its computational complexity. On the other hand, linear detection techniques such as Zero Forcing (ZF) and Minimum Mean Square Error (MMSE) exhibit poor performance. Consequently, we explore the combination of MMSE estimation with ML estimation around a neighborhood of the MMSE estimate. We evaluate the performance of the different schemes in Additive White Gaussian Noise (AWGN), with reference to the number of FDM carriers and their frequency separation. The combined MMSE-ML scheme achieves a near optimum error performance with polynomial complexity for a small number of BPSK FDM carriers. For QPSK modulation the performance of the proposed system improves for a large number of ML comparisons. In all cases, the detectability of the FDM signal is bounded by the signal dimension and the carriers frequency distance.
Major histocompatibility complex class I‐binding peptides are recycled to the cell surface after internalization (1993)

Cytotoxic T lymphocytes (CTL) recognize target antigens as short, processed peptides bound to major histocompatibility complex class I (MHC-I) heavy and light chains (beta 2-microglobulin; beta 2-m). The heavy chain, which comprise the actual peptide binding alpha-1 and alpha-2 domains, can exist at the cell surface in different forms, either free, bound to beta 2-m or as a ternary complex with beta 2-m and peptides. MHC-I chains are also known to internalize, and recycle to the cell surface, and this has been suggested to be important in peptide presentation. Whether MHC-I-bound peptides also can recycle is not known. We have investigated this by using both peptide transporter mutant RMA-S cells and EL4 cells loaded with Db-binding peptides, by two different approaches. First, peptides were covalently linked with galabiose (Gal alpha 4Gal) at a position which did not interfere with Db binding or immunogenicity, and peptide recycling tested with Gal2-specific monoclonal antibodies. By flow cytometry, a return of Gal2 epitopes to the cell surface was found, after cellular internalization and cell surface clearance by pronase treatment. This peptide recycling could be discriminated from free fluid-phase uptake and was inhibited by methylamine, chloroquine and low temperature (18 degrees C) but not by leupeptin. Second, specific CTL were reacted with peptide-loaded target cells after complete removal of surface Db molecules by pronase, and after different times of incubation at 37 degrees C to allow reexpression. By this procedure, reappearance of target cell susceptibility was confirmed. The results are in agreement with a model for optimizing peptide presentation by recycling through an intracellular compartment similar to early endosomes in certain antigen-presenting cells.
Velocity bunching of high-brightness electron beams (2005)

Velocity bunching has been recently proposed as a tool for compressing electron beam pulses in modern high brightness photoinjector sources. This tool is familiar from earlier schemes implemented for bunching dc electron sources, but presents peculiar challenges when applied to high current, low emittance beams from photoinjectors. The main difficulty foreseen is control of emittance oscillations in the beam in this scheme, which can be naturally considered as an extension of the emittance compensation process at moderate energies. This paper presents two scenarios in which velocity bunching, combined with emittance control, is to play a role in nascent projects. The first is termed ballistic bunching, where the changing of relative particle velocities and positions occur in distinct regions, a short high gradient linac, and a drift length. This scenario is discussed in the context of the proposed ORION photoinjector. Simulations are used to explore the relationship between the degree of bunching, and the emittance compensation process. Experimental measurements performed at the UCLA Neptune Laboratory of the surprisingly robust bunching process, as well as accompanying deleterious transverse effects, are presented. An unanticipated mechanism for emittance growth in bends for highly momentum chirped beam was identified and studied in these experiments. The second scenario may be designated as phase space rotation, and corresponds closely to the recent proposal of Ferrario and Serafini. Its implementation for the compression of the electron beam pulse length in the PLEIADES inverse Compton scattering (ICS) experiment at LLNL is discussed. It is shown in simulations that optimum compression may be obtained by manipulation of the phases in low gradient traveling wave accelerator sections. Measurements of the bunching and emittance control achieved in such an implementation at PLEIADES, as well as aspects of the use of velocity-bunched beam directly in ICS experiments, are presented.
Pro-Inflammatory Mediation of Myoblast Proliferation (2014)

Skeletal muscle satellite cell function is largely dictated by the surrounding environment following injury. Immune cell infiltration dominates the extracellular space in the injured area, resulting in increased cytokine concentrations. While increased pro-inflammatory cytokine expression has been previously established in the first 3 days following injury, less is known about the time course of cytokine expression and the specific mechanisms of cytokine induced myoblast function. Therefore, the expression of IL-1β and IL-6 at several time points following injury, and their effects on myoblast proliferation, were examined. In order to do this, skeletal muscle was injured using barium chloride in mice and tissue was collected 1, 5, 10, and 28 days following injury. Mechanisms of cytokine induced proliferation were determined in cell culture using both primary and C2C12 myoblasts. It was found that there is a ∼20-fold increase in IL-1β (p≤0.05) and IL-6 (p = 0.06) expression 5 days following injury. IL-1β increased proliferation of both primary and C2C12 cells ∼25%. IL-1β stimulation also resulted in increased NF-κB activity, likely contributing to the increased proliferation. These data demonstrate for the first time that IL-1β alone can increase the mitogenic activity of primary skeletal muscle satellite cells and offer insight into the mechanisms dictating satellite cell function following injury.
Inhibition of Leukocyte Function by Serum from Patients with Trichinellosis (1990)

Modification of leukocytic function has been reported in only a few human parasitic diseases. In this study we evaluated the effects of the sera from patients infected with Trichinella on chemotactic and phagocytic responses in leukocytes. Leukocyte chemotaxis was tested by the agarose method and phagocytosis by the technique of Yamamura, modified for Saccharomyces cerevisiae. Sera were acquired from patients during a trichinellosis outbreak that occurred in northern Italy in 1986. The parasite was isolated from 1 patient and isoenzymatically typed as Trichinella sp. 3, a new taxon, previously considered Trichinella nelsoni. The results indicated that sera from Trichinella-infected humans inhibited both chemotaxis and phagocytic responses in leukocytes. These findings suggest the existence of serum factor(s) in trichinellosis patients that modify host leukocytic functions. The source and nature of active serum components and the mechanism by which they modulate leukocyte function remain to be clarified.
A highly conserved lens transcriptional control element from the Pax-6 gene (1998)

We have identified a short segment of the mouse Pax-6 gene 5' flanking region that is necessary and sufficient for reporter construct expression in components of the eye derived from non-neural ectoderm. This transcriptional control element has a highly conserved nucleotide sequence over 341 bp and is located approximately 3.5 kb upstream of the start-point for transcription from the most proximal promoter (PO) of the Pax-6 gene. The level of identity between the human and mouse Pax-6 genes in this region is 93%. When combined either with its natural promoter or a heterologous minimal promoter, this element directs reporter construct expression to a region of surface ectoderm overlying the optic cup beginning at E8.5-9.0 (12-14 somites). Subsequently, expression is restricted to the lens (primarily the lens epithelium) and the corneal epithelium. This element will provide an important tool in future transgenic analyses of lens formation and will allow identification of transcription factors with a central function in lens development.
Non-coherent MIMO Communication for the 5th Generation Mobile: Overview and Practical Aspects (2014)

Current cellular technologies are based on the concept of coherent communication, in which the channel matrix used for demodulation is estimated via reference or pilot signals. Coherent systems involve a significant increase of the signaling overhead, either when the number of Transmission Points (TP) is increased, due to the use of Coordinated Multipoint transmission/reception (CoMP) with Multiple-Input Multiple-Output (MIMO) processing, or when mobile channel changes rapidly. Another disadvantage of coherent communications is the performance degradation caused by channel estimation errors. Both drawbacks of coherent communication motivate the use of non-coherent techniques. Although there are many theoretical studies on the performance of non-coherent schemes in MIMO systems, their impact on real-world cellular systems is still unknown. This paper focuses on bringing non-coherent techniques into practical systems using CoMP and/or MIMO processing.
An Integrated, Software-Defined FDD Transceiver: Distributed Duplexing Theory and Operation (2019)

Implementing flexible, software-defined duplexing transceivers remains challenging due to the inherent self-interference from TX to RX that requires cancellation in the RF/analog domain. Previously, we presented a novel, duplexing, integrated, single antenna transceiver architecture that used an M-stage distributed amplifier combined with an artificial transmission line to achieve high transmit-receive isolation across more than an octave in center frequency. In this paper, we explain and explore the trade-offs and limits on this class of distributed, duplexing transceivers as a function of system and sub-circuit parameters.
Semantic Enhancement Engine: A Modular Document Enhancement Platform for Semantic Applications over Heterogeneous Content (2002)

Abstract. Traditionally, automatic classification and metadata extraction have been performed in isolation, usually on unformatted text. SCORE Enhancement Engine (SEE) is a component of a Semantic Web technology called the Semantic Content Organization and Retrieval Engine (SCORE). SEE takes the next natural steps by supporting heterogeneous content (not only unformatted text), as well as following up automatic classification with extraction of contextually relevant, domain-specific (i.e., semantic) metadata. Extraction of semantic metadata not only includes identification of relevant entities but also relationships within the context of relevant ontology. This paper describes SEE&apos;s architecture, which provides a common API for heterogeneous document processing, with discrete, reusable and highly configurable modular components. This results in exceptional flexibility, extensibility and performance. Referred to as SEE modules (SEEMs), which are divided along functional lines, these processors perform one of the following roles: restriction (determine the segments of the input text to operate upon); enhancement (discover textual features of semantic interest); filtering (augment, remove or supplement the features recognized); or
Neonatal and Infantile Immune Responses to Encapsulated Bacteria and Conjugate Vaccines (2008)

Encapsulated bacteria are responsible for the majority of mortality among neonates and infants. The major components on the surface of these bacteria are polysaccharides which are important virulence factors. Immunity against these components protects against disease. However, most of the polysaccharides are thymus-independent (TI)-2 antigens which induce an inadequate immune response in neonates and infants. The mechanisms that are thought to play a role in the unresponsiveness of this age group to TI-2 stimuli will be discussed. The lack of immune response may be overcome by conjugating the polysaccharides to a carrier protein. This transforms bacterial polysaccharides from a TI-2 antigen into a thymus-dependent (TD) antigen, thereby inducing an immune response and immunological memory in neonates and infants. Such conjugated vaccines have been shown to be effective against the most common causes of invasive disease caused by encapsulated bacteria in neonates and children. These and several other approaches in current vaccine development will be discussed.
Guiding light with conformal transformations (2009)

The past decade has seen a revolution in electromagnetics due to the development of metamaterials. These artificial composites have been fashioned to exhibit exotic effects such as a negative index of refraction. However, the full potential of metamaterial devices has only been hinted at. By combining metamaterials with transformation optics (TO), researchers have demonstrated an invisibility cloak. Subsequently, quasi-conformal mapping was used to create a device that exhibited a broadband cloaking effect. Here we extend this latter approach to a strictly conformal mapping to create reflection less, inherently isotropic, and broadband photonic devices. Our method combines the novel effects of TO with the practicality of all-dielectric construction. We show that our structures are capable of guiding light in an almost arbitrary fashion over an unprecedented range of frequencies.
CHOLESTEROL ,L IPOPROTEINS, AND BREAST CANCER RISK IN AFRICAN AMERICAN WOMEN (2012)

Background: Lipid levels, including high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides, have been reported to be associated with breast cancer risk. Methods: We studied African American women (97 breast cancer cases and 102 controls) accrued through a population-based, case-control study in the Washington, DC metropolitan area during 1997 and 1998. Plasma lipid levels were measured using enzymatic methods. Logistic regressions (adjusted for age, age at menarche, parity, previous alcohol consumption, and education) were used to explore the associations between lipid levels and breast cancer. Results: Through multivariable-adjusted regression, we observed a significant inverse association between breast cancer risk and increasing levels of total cholesterol (OR=.46, 95% CI=.25-.85) and LDL (OR=.41, 95% CI=.21-.81), whereas lower levels of HDL were associated with a significant increase in risk (OR=1.99, 95% CI=1.06-3.74). Conclusions: Our data demonstrate significant reductions in breast cancer risk with high levels of total cholesterol and significant increase in risk when HDL levels are low. These data are in support of a protective effect of cholesterol which has been reported in other populations; further, these findings add to the literature in an understudied population, African American women.
Characterization of fullerenes by mass spectrometry (1992)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCharacterization of fullerenes by mass spectrometryStephen W. McElvany, Mark M. Ross, and John H. CallahanCite this: Acc. Chem. Res. 1992, 25, 3, 162–168Publication Date (Print):March 1, 1992Publication History Published online1 May 2002Published inissue 1 March 1992https://pubs.acs.org/doi/10.1021/ar00015a010https://doi.org/10.1021/ar00015a010research-articleACS PublicationsRequest reuse permissionsArticle Views905Altmetric-Citations104LEARN 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
Selectivity of Amidoxime Polymers for the Sorption of Gallate (1995)

Abstract The sorption of gallium from alkaline solution using amidoxime resins or polyampholytes was studied. Gallium is extracted by amidoxime resins, even from Bayer leachates, but amidoxime polyampholytes are limited to dilute alkali hydroxide solution up to 5 M. The elution of gallium runs well with acetylacetone.
Synthesis of (Dialkylamino)alkyl-Disubstituted Pyrimido[5,6,1-de]acridines, a Novel Group of Anticancer Agents Active on a Multidrug Resistant Cell Line (1995)

A series of pyrimidoacridine derivatives with two basic side chains, 7a-e, was synthesized, as potential antitumor drugs, starting from 2-[2-(dimethylamino)ethyl]-6-chloropyrimido[5,6,1-de]acridine-1,3, 7- trione (6) and a suitable (alkylamino)alkylamine. The products 6 and 7a-e showed significant cytotoxic activity in vitro against L1210 leukemia. Compounds 7a,d were 2 orders of magnitude more cytotoxic than ametantrone. All compounds were also examined for their activity on LoVo and resistant LoVo/Dx cell lines. Unlike ametantrone, the compounds have shown to be able to overcome the multidrug resistance. Compounds 7a,d, the two most active in vitro, were tested in vivo against murine P388 leukemia showing good activity.
On the Importance of Temporal Context in Proximity Kernels: A Vocal Separation Case Study (2017)

Musical source separation methods exploit source-specific spectral characteristics to facilitate the decomposition process. Kernel Additive Modelling (KAM) models a source applying robust statistics to time-frequency bins as specified by a source-specific kernel, a function defining similarity between bins. Kernels in existing approaches are typically defined using metrics between single time frames. In the presence of noise and other sound sources information from a single-frame, however, turns out to be unreliable and often incorrect frames are selected as similar. In this paper, we incorporate a temporal context into the kernel to provide additional information stabilizing the similarity search. Evaluated in the context of vocal separation, our simple extension led to a considerable improvement in separation quality compared to previous kernels.