gebhart/patrepeval huggingface dataset:
Designing Peptide Inhibitors for Oligomerization and Toxicity of Alzheimer's β-Amyloid Peptide (2008)

Convergent biochemical and genetic evidence suggests that the formation of beta-amyloid (Abeta) deposits in the brain is an important and, probably, seminal step in the development of Alzheimer's disease (AD). Recent studies support the hypothesis that Abeta soluble oligomers are the pathogenic species that prompt the disease. Inhibiting Abeta self-oligomerization could, therefore, provide a novel approach to treating the underlying cause of AD. Here, we designed potential peptide-based aggregation inhibitors containing Abeta amino acid sequences (KLVFF) from part of the binding region responsible for Abeta self-association (residues 16-20), with RG-/-GR residues added at their N- and C-terminal ends to aid solubility. Two such peptides (RGKLVFFGR, named OR1, and RGKLVFFGR-NH2, named OR2) were effective inhibitors of Abeta fibril formation, but only one of these peptides (OR2) inhibited Abeta oligomer formation. Interestingly, this same OR2 peptide was the only effective inhibitor of Abeta toxicity toward human neuroblastoma SH-SY5Y cells. Our data support the idea that Abeta oligomers are responsible for the cytotoxic effects of Abeta and identify a potential peptide inhibitor for further development as a novel therapy for AD.
Statistical Image Processing With A Hybrid Flying Window Scanning System (1986)

The local statistics of an image are needed, for example, to transform the input into stationary data for which many standard enhancement/coding algorithms are optimized, as well as to implement locally adaptive processing techniques. We discuss a system that uses a flying window scanner to extract the second-order parameters (local mean, variance, and correlation length) in real time and show how these parameters can be used to transform an input into block stationary data. The same scanning system is also applied to the measurement of a variety of histograms in a single frame scan.
Random spacing channel assignment to reduce the nonlinear intermodulation distortion in cellular mobile communications (1999)

In cellular mobile communications, only a subset of all available frequency channels are assigned to each cell, hence, the interchannel spacing of channels is wider than the required minimum. In this paper, a random spacing channel assignment (RSCA) scheme is proposed which exploits the wider interchannel spacing of assigned channels in each cell to reduce the most deleterious third-order intermodulation distortion caused by the nonlinear devices, such as hard limiters or nonlinear power amplifiers. Results show that the proposed RSCA scheme can reduce the third-order intermodulation noise power by approximately 4-5 dB and yet it can still satisfy the minimum adjacent channel spacing requirement.
Developmental changes in localization of NMDA receptor subunits in primary cultures of cortical neurons (1998)

Immunoblot analysis, using antibodies against distinct N-methyl-D-aspartic acid (NMDA) receptor subunits, illustrated that the NR2A and NR2B subunit proteins have developmental profiles in cultured cortical neurons similar to those seen in vivo. NR1 and NR2B subunits display high levels of expression within the first week. In contrast, the NR2A subunit is barely detectable at 7 days in vitro (DIV) and then gradually increased to mature levels at DIV21. Immunocytochemical analysis indicated that NMDA receptor subunits cluster in the dendrites and soma of cortical neurons. Clusters of NR1 and NR2B subunits were observed as early as DIV3, while NR2A clusters were rarely observed before DIV10. At DIV18, NR2B clusters partially co-localize with those of NR2A subunits, but NR2B clusters always co-localize with those of NR1 subunits. Synapse formation, as indicated by the presence of presynaptic synaptophysin staining, was observed as early as 48-72 h after plating. However, in several neurons at ages less than DIV5 where synapses were scarce, NR2B and NR1 clusters were abundant. Furthermore, while NR2B subunit clusters were seen both at synaptic and extrasynaptic sites, NR2A clusters occurred almost exclusively in front of synaptophysin-labelled boutons. This result was supported by electrophysiological recording of NMDA-mediated synaptic activity [NMDA-excitatory postsynaptic currents (EPSCs)] in developing neurons. At DIV6, but not at DIV12, CP101, 606, a NR1/NR2B receptor antagonist, antagonized spontaneously occurring NMDA-EPSCs. Our data indicate that excitatory synapse formation occurs when NMDA receptors comprise NR1 and NR2B subunits, and that NR2A subunits cluster preferentially at synaptic sites.
Modeling instantaneous intonation for speaker identification using the fundamental frequency variation spectrum (2009)

In recent years, the field of automatic speaker identification has begun to exploit high-level sources of speaker-discriminative information, in addition to traditional models of spectral shape. These sources include pronunciation models, prosodic dynamics, pitch, pause, and duration features, phone streams, and conversational interaction. As part of this broader thrust, we explore a new frame-level vector representation of the instantaneous change in fundamental frequency, known as fundamental frequency variation (FFV). The FFV spectrum consists of 7 continuous coefficients, and can be directly modeled in a standard Gaussian mixture model (GMM) framework. Our experiments indicate that FFV features contain useful information for discriminating among speakers, and that model-space combination of FFV and cepstral features outperforms cepstral features alone. In particular, our results on 16kHz Wall Street Journal data show relative reductions in error rate of 54% and 40% for female and male speakers, respectively.
Design of wideband hybrid amplifiers for local area networks (2001)

Optimisation of design parameters of hybrid fibre amplifiers for multi-wavelength operation in local area networks is presented. The authors consider hybrid amplifiers consisting of a distributed Raman fibre amplifier (RFA) and a remotely pumped discrete erbium-doped fibre amplifier (EDFA). The design is based on a numerical model that includes pump-to-pump and signal-to-signal interactions and generation of amplified spontaneous emission (ASE) in the RFA, and solves the standard rate equations and propagation equations for pump, signal and ASE spectral components within the EDFA. An efficient average power analysis algorithm has been used to solve the equations. To achieve a 40 nm bandwidth with gain ripple less than 10% and net gain higher than 10 dB, three pump laser diodes (LDs) must be used when wavelength-division-multiplexed (WDM) signals are transmitted in the C-band, but only one pump LD is sufficient for 50 WDM channels with 0.8 nm spacing placed in the L-band.
Taming user-generated content in mobile networks via Drop Zones (2011)

Smartphones have changed the way people communicate. Most prominently, using commonplace mobile device features (e.g., high resolution cameras), they started producing and uploading large amounts of content that increases at an exponential pace. In the absence of viable technical solutions, some cellular network providers are considering to start charging special usage fees to address the problem. Our contributions are twofold. First, we find that the user-generated content problem is a user-behavioral problem. By analyzing user mobility and data logs of close to 2 million users of a cellular network, we find that (i) users upload content from a small number of locations, typically corresponding to their home or work locations; (ii) because such locations are different for different users, we find that the problem appears ubiquitous, since user-generated content uploads grow exponentially at most locations. However, we also find that (Hi) there exists a significant lag between content generation and uploading times. For example, we find that 55% of content that is uploaded via mobile phones is at least 1 day old. Second, based on the above insights, we propose a new cellular network architecture. Our approach proposes capacity upgrades at a select number of locations called Drop Zones. Although not particularly popular for uploads originally, Drop Zones seamlessly fall within the natural movement patterns of a large number of users. They are therefore better suited for uploading larger quantities of content in a postponed manner. We design infrastructure placement algorithms and demonstrate that by upgrading infrastructure in only 963 base-stations across the entire United States, it is possible to deliver 50% of total content via the Drop Zones.
A gradient wind error model for the Blanchard algorithm (2003)

Although the Blanchard algorithm (IEEE Trans. Aerospace and Electronic Sys., vol. AES-8, no. 5, 1972) is for the most part successful and a great improvement over a simple pressure altitude algorithm, long-range missions with a wide variation in latitude have often shown a systematic trend in how the altitude error grows with time. It is hypothesized that the geostrophic wind assumption often becomes a limiting factor depending on the daily weather patterns and in particular on the amount of curvature in the high altitude jet stream. The ability to use meteorological data at a particular locale was not anticipated. Even today, it would be impractical and inaccurate to prepare such data from outside sources. The ability to estimate the radius of curvature as part of an error model in the navigation Kalman filter is a new idea warranting further investigation. Under the assumption of a gradient wind, Blanchard's algorithm is derived along with the partials for a new error state. Test results using actual flight data show the improvement of the model over an ordinary barometric altimeter bias error model.
Microwave Si avalanche diode with nearly-abrupt-type junction (1967)

Microwave Si avalanche diodes with a nearly-abupt-type junction have been made. The maximum output power so far obtained in CW operation is 1.1 watts at 12 GHz with an efficiency of 7.7 percent. The maximum efficiency observed is 8.0 percent. The improved performance over the previously reported <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">p \nu n</tex> structure, for which the best result was 250 mW at 12 GHz with an efficiency of 2.8 percent results from a reduction in length of the avalanche region in the abrupt junction. In the previously reported <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">p \nu n</tex> diode the efficiency is still sharply increasing at the burnout point, while in the present diode the efficiency is nearly saturated at the burn-out point. The advantages and disadvantages of using different polarity of the diode (p on n or n on p) and different material (Ge) are given. Small-signal theory was used to analyze device operation.
Natural and recombinant DNA-derived human insulin-like growth factor-I compared for use in radioligand assays. (1987)

We compared two preparations of human insulin-like growth factor (IGF)-I, one isolated from human plasma and the other prepared by recombinant DNA technology, for use in three radioimmunoassays and a radioreceptor assay for IGF-I, two radioreceptor assays for IGF-II, and a protein-binding assay for both IGFs. In the IGF-I assays, iodinated natural IGF-I consistently showed higher binding than did iodinated biosynthetic IGF-I, whether or not the iodopeptides were purified before use by hydrophobic interaction chromatography. Comparing the potency of the unlabeled peptides in the eight assay systems, we found the natural and the biosynthetic IGF-I to be equipotent in every case except for a radioimmunoassay involving a monoclonal IGF-I antibody (the synthetic peptide had 2.4 times greater activity), and an IGF-II radioreceptor assay involving ovine placental membrane receptors (the natural peptide had 10-fold greater activity). We conclude that recombinant DNA-derived IGF-I is suitable for use, both as a standard and as a radioligand, in a wide variety of IGF assays.
Struggling or exploring? (2014)

Web searchers often exhibit directed search behaviors such as navigating to a particular Website. However, in many circumstances they exhibit different behaviors that involve issuing many queries and visiting many results. In such cases, it is not clear whether the user's rationale is to intentionally explore the results or whether they are struggling to find the information they seek. Being able to disambiguate between these types of long search sessions is important for search engines both in performing retrospective analysis to understand search success, and in developing real-time support to assist searchers. The difficulty of this challenge is amplified since many of the characteristics of exploration (e.g., multiple queries, long duration) are also observed in sessions where people are struggling. In this paper, we analyze struggling and exploring behavior in Web search using log data from a commercial search engine. We first compare and contrast search behaviors along a number dimensions, including query dynamics during the session. We then build classifiers that can accurately distinguish between exploring and struggling sessions using behavioral and topical features. Finally, we show that by considering the struggling/exploring prediction we can more accurately predict search satisfaction.
An 8-ns random cycle embedded RAM macro with dual-port interleaved DRAM architecture (D/sup 2/RAM) (2000)

A novel fast random cycle embedded RAM macro with dual-port interleaved DRAM architecture (D/sup 2/RAM) has been developed. The macro exploits three key circuit techniques: dual-port interleaved DRAM architecture, two-stage pipelined circuit operation, and write before sensing. Random cycle time of 8 ns under worst-case conditions has been confirmed with a 0.25-/spl mu/m embedded DRAM test chip. This is six times faster than conventional DRAM.
A full-rate, full-diversity four-antenna quasi-orthogonal space-time block code (2005)

We present a complex, full-rate quasi-orthogonal space-time block code for four transmit antennas. Using carefully tailored constellation phase rotations, we show that this code achieves full diversity for specialized PSK-based constellations. The optimal receiver for the new code decouples the symbol detection problem into pairs of symbols, thus greatly reducing complexity. Finally, we present and compare performance of the new code with several other codes in the literature. The new code is shown to perform as well as the best known code of its class.
Digital signal processing in read channels (2006)

Digital signal processing (DSP) has been a key technology in read channels, contributing significantly to the dramatic storage capacity and data rate growth of hard disk drives. This tutorial paper provides an overview of magnetic recording trends, and it discusses the DSP algorithms and architectures that have been employed in read channels for equalization, detection and coding. This paper also presents both a read channel and a hard disk drive SoC chip in 0.16 /spl mu/m CMOS process.
Coronary artery flow monitoring following coronary interventions (1995)

Coronary guidewires with ultrasound transducer tips are commercially available and are appropriately sized for use in coronary interventions. These guidewires permit monitoring of coronary flow before, during and after the interventions. The measured flow signal contains valuable information regarding the quality and the stability of the final result. After completion of the procedure, monitoring the trend in average velocity over several minutes can reveal subtle alterations in flow that may presage abrupt closure. Abnormal or unstable flow patterns also may help predict lesions that might develop recurrences in the weeks and months after successful procedures.
Nickel(0) Complexes of N-Alkyl-Substituted N-Heterocyclic Carbenes and Their Use in the Catalytic Carbon−Carbon Bond Activation of Biphenylene (2006)

The reaction of [Ni(COD)2] with stable N-heterocyclic carbenes R2Im (R2Im = 1,3-di(R)imidazole-2-ylidene; R2 = Me2, nPr2, MeiPr, iPr2) affords homoleptic [Ni(Me2Im)3] (1) or dinuclear, COD-bridged complexes of the type [Ni2(R2Im)4(COD)] (R2 = nPr2, 2; MeiPr, 3; iPr2, 4). Compounds 1−4 are suitable precursors for the synthesis of [Ni(R2Im)2]-containing complexes in solution, exemplified by the reaction with CO under atmospheric pressure, with equimolar amounts of diphenyl acetylene or with biphenylene to give carbonyl complexes [Ni(R2Im)2(CO)2] (R2 = Me2, 5; nPr2, 6; MeiPr, 7; iPr2, 8), diphenyl acetylene complexes [Ni(R2Im)2(η2-C2Ph2)] (R2 = Me2, 9; nPr2, 10; MeiPr, 11; iPr2, 12), and biphenylene complexes [Ni(R2Im)2(2,2‘-biphenyl)] (R2 = Me2, 13; nPr2, 14; MeiPr, 15; iPr2, 16). Furthermore, the reaction of 4 with 3-hexyne or 2-butyne afforded [Ni(iPr2Im)2(η2-C2R2)] (R = Me, 18; Et, 19) in good yields. The compounds 1, 11, 13, 17, and 18 have been structurally characterized. Complexes 13−16 are the products of a stoichiometric carbon−carbon activation of biphenylene, and compounds 1−4 (as well as 9−12) are efficient catalysts for the insertion of diphenyl acetylene into the C−C bond of biphenylene, a process in which the C−C activation of biphenylene is incorporated into a catalytic cycle. The reaction rate of the formation of 9,10-di(phenyl)phenanthrene depends on the nature of the carbene ligand of the catalyst; the highest was observed for [Ni2(iPr2Im)4(COD)] (4).
Common mode signal rejection methods for MRI: Reduction of cable shield currents for high static magnetic field systems (2003)

Abstract This experiment was conducted to identify common mode currents that flow on the shield of a coaxial cable and to investigate techniques that reduce their effects at high fields of ≥3 Tesla. It will be shown that there are two different methods of common mode interference for two different coil types. First, is the transceive case, where common mode cable shield currents flow as a result of unbalanced loop voltages that couple to the cable shield. In the second case, unwanted common mode signals are induced from the field of the transmission coil onto the cable shield of the receive‐only coil. Two important factors relating to the investigation of common mode signals are danger to the patient from an RF burn and the reduction of the signal‐to‐noise ratio (SNR) because of extra noise being introduced into the MRI environment. It will be shown that through the use of cable shield traps and balun matching circuits, common mode signals can be reduced significantly, increasing patient safety and SNR. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 19B: 1–8, 2003.
A scheme for pitch extraction of speech using autocorrelation function with frame length proportional to the time lag (1992)

Although pitch extraction schemes based on the short-time autocorrelation function offer reliable results for most of the speech signal, the autocorrelation peaks indicating fundamental period fluctuate with frame position, causing occasional pitch extraction errors. In order to reduce these errors, a scheme using a new definition of normalized short-time autocorrelation function is proposed. One of the major advantages of the definition over conventional ones is that the frame length changes in proportion to the time lag, and, therefore, the input speech can be analyzed without any knowledge of the fundamental frequency range of the speaker. Two methods are proposed for the normalization, and the one compensating for variations of the short-time power of the waveform is shown to offer better results. A system for pitch extraction is constructed on a workstation, and the validity of the proposed scheme is demonstrated by experiments using the connected speech of male and female announcers.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
Analytical study of a free-wing/free-trimmer concept (1978)

The free-wing/free-trimmer is a NASA-Conceived extension of the free-wing concept intended to permit the use of high-lift flaps. Wing pitching moments are balanced by a smaller, external surface attached by a boom or equivalent structure. The external trimmer is, itself, a miniature free wing, and pitch control of the wing-trimmer assembly is effected through a trailing-edge control tab on the trimmer surface. The longitudinal behavior of representative small free-wing/free-trimmer aircraft was analyzed. Aft-mounted trimmer surfaces are found to be superior to forward trimmers, although the permissible trimmer moment arm is limited, in both cases, by adverse dynamic effects. Aft-trimmer configurations provide excellent gust alleviation and meet fundamental stick-fixed stability criteria while exceeding the lift capabilities of pure free-wing configurations.
Fine Tuning the Adhesive Properties of a Soft Nanostructured Adhesive with Rheological Measurements (2009)

International audience
Enhanced isolation of SARS-CoV-2 by TMPRSS2-expressing cells (2020)

A novel betacoronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which caused a large respiratory outbreak in Wuhan, China in December 2019, is currently spreading across many countries globally. Here, we show that a TMPRSS2-expressing VeroE6 cell line is highly susceptible to SARS-CoV-2 infection, making it useful for isolating and propagating SARS-CoV-2. Our results reveal that, in common with SARS- and Middle East respiratory syndrome-CoV, SARS-CoV-2 infection is enhanced by TMPRSS2.
Assessing Export Platforms: The Case of Singapore (2000)

CAER II Discussion Paper, 2000, April 2000, No. 72, Harvard Institute of International Development, 46 pp.
Monoalkylation of hydroquinone (1974)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMonoalkylation of hydroquinoneMelvin S. Newman and James A. CellaCite this: J. Org. Chem. 1974, 39, 2, 214–215Publication Date (Print):January 1, 1974Publication History Published online1 May 2002Published inissue 1 January 1974https://pubs.acs.org/doi/10.1021/jo00916a020https://doi.org/10.1021/jo00916a020research-articleACS PublicationsRequest reuse permissionsArticle Views568Altmetric-Citations17LEARN 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