gebhart/patrepeval huggingface dataset:
<i>In vitro</i> suicide inhibition of self-splicing of a group I intron from <i>Pneumocystis carinii</i> by an <i>N</i> 3′ → <i>P</i> 5′ phosphoramidate hexanucleotide (1999)

Binding enhancement by tertiary interactions is a strategy that takes advantage of the higher order folding of functionally important RNAs to bind short nucleic acid-based compounds tightly and more specifically than possible by simple base pairing. For example, tertiary interactions enhance binding of specific hexamers to a group I intron ribozyme from the opportunistic pathogen Pneumocystis carinii by 1,000- to 100,000-fold relative to binding by only base pairing. One such hexamer, d(AnTnGnAnCn)rU, contains an N3' --> P5' phosphoramidate deoxysugar-phosphate backbone (n) that is resistant to chemical and enzymatic decay. Here, it is shown that this hexamer is also a suicide inhibitor of the intron's self-splicing reaction in vitro. The hexamer is ligated in trans to the 3' exon of the precursor, producing dead-end products. At 4 mM Mg2+, the fraction of trans-spliced product is greater than normally spliced product at hexamer concentrations as low as 200 nM. This provides an additional level of specificity for compounds that can exploit the catalytic potential of complexes with RNA targets.
Surface Expression of Inward Rectifier Potassium Channels Is Controlled by Selective Golgi Export (2003)

Traffic of integral membrane proteins along the secretory pathway is not simply a default process but can be selective. Such selectivity is achieved by sequence information within the cargo protein that recruits coat protein complexes to drive the formation of transport vesicles. A number of sequence motifs have been identified in the cytoplasmic domains of ion channels that regulate early trafficking events between the endoplasmic reticulum and the Golgi complex. Here, we demonstrate that the following trafficking step from the Golgi compartment to the plasma membrane can also be selective. The N-terminal domain of the inward rectifier potassium channel Kir2.1 contains specific sequence information that is necessary for its efficient export from the Golgi complex. Lack of this information results in accumulation of the protein within the Golgi and a significant decrease in cell surface expression. As similar results were obtained for the N terminus of another Kir channel subfamily member, Kir4.1, which could functionally substitute for the Kir2.1 N terminus, we propose a more general role of the identified N-terminal domains for post-Golgi trafficking of Kir channels.
Enhancement of Excretory Production of an Exoglucanase from Escherichia coli with Phage Shock Protein A (PspA) Overexpression (2011)

Production of recombinant proteins by excretory expression has many advantages over intracellular expression in Escherichia coli. Hyperexpression of a secretory exoglucanase, Exg, of Cellulomonas fimi was previously shown to saturate the SecYEG pathway and result in dramatic cell death of E. coli. In this study, we demonstrated that overexpression of the PspA in the JM101(pM1VegGcexL-pspA) strain enhanced excretion of Exg to 1.65 U/ml using shake-flask cultivation, which was 80% higher than the highest yield previously obtained from the optimized JM101(pM1VegGcexL) strain. A much higher excreted Exg activity of 4.5 U/ml was further achieved with high cell density cultivation using rich media. Furthermore, we showed that the PspA overexpression strain enjoyed an elevated critical value (CV), which was defined as the largest quotient between the intracellular unprocessed precursor and its secreted mature counterpart that was still tolerable by the host cells prior to the onset of cell death, improving from the previously determined CV of 20/80 to the currently achieved CV of 45/55 for Exg. The results suggested that the PspA overexpression strain might tolerate a higher level of precursor Exg making use of the SecYEG pathway for secretion. The reduced lethal effect might be attributable to the overexpressed PspA, which was postulated to be able to reduce membrane depolarization and damage. Our findings introduce a novel strategy of the combined application of metabolic engineering and construct optimization to the attainment of the best possible E. coli producers for secretory/excretory production of recombinant proteins, using Exg as the model protein.
MINERAL TRAPPING OF CO2 VIA OIL SHALE ASH AQUEOUS CARBONATION: CONTROLLING MECHANISM OF PROCESS RATE AND DEVELOPMENT OF CONTINUOUS-FLOW REACTOR SYSTEM; pp. 40–58 (2009)

Ash containing considerable amounts of free lime as the most active compoÂ­nent requires stabilization to assure safe landfilling. Using CO2 from flue gases as a neutralizing agent, also the emission of CO2 is diminished. The most extensive effect could be achieved by treating ash-water suspensions with CO2-containÂ­ing gas. As even minute amounts of extraneous substances present in water influence the extent and rate of lime solubility in water, the behavior of lime as the key component of ash in various conditions was studied and the mechanism of process deceleration was proposed. As the next step, a laboratory-scale continuous-flow reactor system for aqueous carbonaÂ­tion of oil shale ash and main considerations for industrial pilot-scale plant design were developed.
Depth from focusing and defocusing (2002)

The problem of obtaining depth information from focusing and defocusing is studied. In depth from focusing, instead of the Fibonacci search, which is often trapped in local maxima, the combination of Fibonacci search and curve fitting is proposed. This combination leads to an unprecedentedly accurate result. A model of the blurring effect that takes geometric blurring as well as imaging blurring into consideration in the calibration of the blurring model is proposed. In spectrogram-based depth from defocusing, a maximal resemblance estimation method is proposed to decrease or eliminate the window effect.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Catalytic Hydrogenation of Carbon Dioxide Using Ir(III)−Pincer Complexes (2009)

Catalytic hydrogenation of carbon dioxide in aqueous potassium hydroxide was performed using a newly synthesized isopropyl-substituted PNP-pincer iridium trihydride complex as a catalyst. Potassium formate was obtained with turnover numbers up to 3,500,000 and a turnover frequency of 150,000 h(-1), both of which are the highest values reported to date.
Convective Assembly of a Particle Monolayer (2015)

Recently, the steady-state process of convective assembly has emerged as a viable production route for colloidal monolayers. The present study models the regions of particle assembly: Region I comprises convective concentration of a particle suspension in a liquid below a meniscus, Region II comprises permeation of fluid through the dense particle monolayer, and Region III comprises capillary densification. For each region, the dominant physics and nondimensional groups are identified, and quantitative models are derived to describe the evolution of microstructure in terms of the main process parameters. The concentration profile within the assembly zone of Region I is predicted, including the role of a concentration-dependent diffusion constant and the shape of the meniscus. The fluid flow through the assembled monolayer is treated in Region II, along with a stability calculation to reveal that isolated particle clusters do not survive on top of the monolayer. The physics of capillary crystallization is addressed in Region III, with an emphasis on the density of cracks that emerge. The Peclet number and Capillary number both play important roles but in different regions of the assembly process.
Simulator Sickness in Virtual Environments. (1995)

Abstract : Virtual Reality (also known as Virtual Environment or VE) technology shows many promising applications in areas of training, medicine, architecture, astronomy, data handling, teleoperation, and entertainment. A potential threat to using this - technology is the mild to severe discomfort that some users experience during or after a VE session. Similar effects have been observed with flight and driving simulators. The simulator sickness literature forms a solid background for the study of sickness in virtual environments and many of the findings may be directly applicable. This report reviews literature concerning simulator sickness, motion sickness, and virtual environments. Forty factors that may be associated with simulator sickness in virtual environments are identified. These factors form three global categories: subject, simulator, and task. The known and predicted effects of these factors on sickness in VEs are discussed. A table summarizes the information presented in this report. The information can be used as a guide for future research concerning simulator sickness in virtual environments.
19.8 A 0.0021mm2 1.82mW 2.2GHz PLL using time-based integral control in 65nm CMOS (2016)

Phase-locked loops (PLLs) are de-facto clock generators in analog, digital, RF, and embedded systems to generate a high frequency output clock from a low frequency reference clock. Modern systems-on-chip (SoCs) require many such PLLs that cater to multi-core processors, memories, IO interfaces and power management. A ring-oscillator-based analog charge-pump PLL offers a flexible and power-efficient way to implement such clock multipliers. However, frequency compensation of analog PLLs requires a large loop filter capacitor that occupies significant area. The area penalty is further exacerbated in deep sub-micron CMOS processes due to increasing oscillator gain and gate leakage. For example, a 2GHz PLL in 65nm CMOS requires a 90pF capacitor (R=1kΩ) to achieve 10MHz bandwidth and 70° phase margin. Assuming a capacitor density of 1fF/μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , a 90pF capacitor occupies an area of 0.09mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . Digital PLLs (DPLLs) offer an attractive means to eliminate the loop-filter capacitor [1, 2]. However, quantization error added by its loop components degrades the performance in multiple ways. First, it makes the DPLL loop inherently non-linear causing the steady state to be a bounded limit cycle, which manifests as deterministic jitter (DJ) at the PLL output. Second, it introduces conflicting noise bandwidth requirements, which makes it difficult to achieve low jitter in a power efficient manner. For instance, suppressing TDC quantization error by reducing PLL bandwidth increases the DCO phase noise contribution. As a result, DCO power must be increased to lower its noise contribution. This is especially problematic in ring-oscillator-based DPLLs. Finally, a high-resolution digital-to-analog converter (DAC) needed to interface the DLF output to the ring oscillator typically occupies large area and negates some of the area benefits of DPLLs [1, 2]. In view of these drawbacks, we present a PLL architecture that combines the advantages of analog (no quantization error) and digital PLLs (small area and scalability) by using a time-based integral path. The prototype PLL requires neither a high resolution DAC nor a capacitor and fits in 40μm×52μm (0.0021mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) active area. It achieves 3.8ps <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rms</sub> integrated jitter at 2.2GHz and consumes 1.82mW power.
Effect of interstrain variation on diagnostic DNA amplification of the cytomegalovirus major immediate-early gene region (1992)

The immediate-early region exon 4 sequences of six clinical cytomegalovirus strains were determined and compared with those of laboratory strains AD169 and Towne. Of 407 codons in exon 4, 33 (8.1%) showed interstrain variation at the peptide level and 74 (18%) showed interstrain variation at the nucleotide level. Variation occurred sporadically throughout the exon, and no grouping of strains was apparent. Published oligonucleotide primers proposed for diagnostic detection of cytomegalovirus by polymerase chain reaction have often been based on exon 4 sequences. Some of these primers show sequence mismatches with strains sequenced here. Amplification sensitivity for mismatched strains was reduced up to 100-fold. More-uniform detection sensitivity was achieved with primers of conserved sequence.
Filter Based Feature Selection Methods for Prediction of Risks in Hepatitis Disease (2015)

Recently, large amount of data is widely available in information systems and data mining has attracted a big attention to researchers to turn such data into useful knowledge. This implies the existence of low quality, unreliable, redundant and noisy data which negatively affect the process of observing knowledge and useful pattern. Therefore, researchers need relevant data from huge records using feature selection methods. Feature selection is the process of identifying the most relevant attributes and removing the redundant and irrelevant attributes. In this study, a comparison between filter based feature selection methods based on a well-known dataset (i.e., hepatitis dataset) was carried out and four classification algorithms were used to evaluate the performance of the algorithms. Among the algorithms, Na ve Bayes and Decision Table classifiers have higher accuracy rates on the hepatitis dataset than the others after the application of feature selection methods. The study revealed that feature selection methods are capable to improve the performance of learning algorithms. However, no single filter based feature selection method is the best. Overall, Consistency Subset, Info Gain Attribute Eval, One-R Attribute Eval and Relief Attribute Eval methods performed better results than the others. Filter Based Feature Selection Methods for Prediction of Risks in Hepatitis Disease
Characterization of commercial samples of gum arabic (1993)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCharacterization of commercial samples of gum arabicMohamed E. Osman, Peter A. Williams, Alan R. Menzies, and Glyn O. PhillipsCite this: J. Agric. Food Chem. 1993, 41, 1, 71–77Publication Date (Print):January 1, 1993Publication History Published online1 May 2002Published inissue 1 January 1993https://pubs.acs.org/doi/10.1021/jf00025a016https://doi.org/10.1021/jf00025a016research-articleACS PublicationsRequest reuse permissionsArticle Views1327Altmetric-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
Soft Real-Time Scheduling on Performance Asymmetric Multicore Platforms (2007)

This paper discusses an approach for supporting soft real-time periodic tasks in Linux on performance asymmetric multicore platforms (AMPs). Such architectures consist of a large number of processing units on one or several chips, where each processing unit is capable of executing the same instruction set at a different performance level. We discuss deficiencies of Linux in supporting periodic real-time tasks, particularly when cores are asymmetric, and how such deficiencies were overcome. We also investigate how to provide good performance for non-real-time tasks in the presence of a real-time workload. We show that this can be done by using deferrable servers to explicitly reserve a share of each core for non-real-time tasks. This allows non-real-time tasks to have priority over real-time tasks when doing so will not cause timing requirements to be violated, thus improving non-real-time response times. Experiments show that even small deferrable servers can have a dramatic impact on non-real-time task performance
Performance anomaly of 802.11b (2003)

The performance of the IEEE 802.11b wireless local area networks is analyzed. We have observed that when some mobile hosts use a lower bit rate than the others, the performance of all hosts is considerably degraded. Such a situation is a common case in wireless local area networks in which a host far away from an access point is subject to important signal fading and interference. To cope with this problem, the host changes its modulation type, which degrades its bit rate to some lower value. Typically, 802.11b products degrade the bit rate from 11 Mb/s to 5.5, 2, or 1 Mb/s when repeated unsuccessful frame transmissions are detected. In such a case, a host transmitting for example at 1 Mb/s reduces the throughput of all other hosts transmitting at 11 Mb/s to a low value below 1 Mb/s. The basic CSMA/CA channel access method is at the root of this anomaly: it guarantees an equal long term channel access probability to all hosts. When one host captures the channel for a long time because its bit rate is low, it penalizes other hosts that use the higher rate. We analyze the anomaly theoretically by deriving simple expressions for the useful throughput, validate them by means of simulation, and compare with several performance measurements.
A fourth human MEF2 transcription factor, hMEF2D, is an early marker of the myogenic lineage (1993)

The transition from multipotent mesodermal precursor to committed myoblast and its differentiation into a mature myocyte involve molecular events that enable the cell to activate muscle-specific genes. Among the participants in this process is the myocyte-specific enhancer factor 2 (MEF2) family of tissue-restricted transcription factors. These factors, which share a highly conserved DNA-binding domain including a MADS box, are essential for the expression of multiple muscle genes with cognate target MEF2 sites in cis. We report here a new human MEF2 factor, hMEF2D, which is unique among the members of this family in that it is present not only in myotubes but also in undifferentiated myoblasts, even before the appearance of myogenin. hMEF2D comprises several alternatively spliced products of a single gene, one of which is the human homolog of the Xenopus SRF-related factor SL-1. Like its relatives, cloned hMEF2D is capable of activating transcription via sequence-specific binding to the MEF2 site, recapitulating endogenous tissue-specific MEF2 activity. Indeed, while MEF2D mRNAs are ubiquitous, the protein is highly restricted to those cell types that contain this activity, implicating posttranscriptional mechanisms in the regulation of MEF2D expression. Alternative splicing may be important in this process: two alternative MEF2D domains, at least one of which is specifically included during myogenic differentiation, also correlate precisely with endogenous MEF2 activity. These findings provide compelling evidence that MEF2D is an integral link in the regulatory network for muscle gene expression. Its presence in undifferentiated myoblasts further suggests that it may be a mediator of commitment in the myogenic lineage.
Miniaturised optical encoder (2008)

Optical encoders are pervasive in many sectors of industry including metrology, motion systems, electronics, medical, scanning/ printing, scientific instruments, space research and specialist machine tools. The precision of automated manufacture and assembly has been revolutionised by the adoption of optical diffractive measurement methods. Today's optical encoders comprise discrete components: light source(s), reference and analyser gratings, and a photodiode array that utilise diffractive optic methods to achieve high resolution. However the critical alignment requirements between the optical gratings and to the photodiode array, the bulky nature of the encoder devices and subsequent packaging mean that optical encoders can be prohibitively expensive for many applications and unsuitable for others. We report here on the design, manufacture and test of a miniaturised optical encoder to be used in precision measurement systems. Microsystems manufacturing techniques facilitate the monolithic integration of the traditional encoder components onto a single compound semiconductor chip, radically reducing the size, cost and set-up time. Fabrication of the gratings at the wafer level, by standard photo-lithography, allows for the simultaneous alignment of many devices in a single process step. This development coupled with a unique photodiode configuration not only provides increased performance but also significantly improves the alignment tolerances in both manufacture and set-up. A National Research and Development Corporation type optical encoder chip has been successfully demonstrated under test conditions on both amplitude and phase scales with pitches of 20 micron, 8 micron and 4 micron, showing significantly relaxed alignment tolerances with signal-to-noise ratios greater than 60:1. Various reference mark schemes have also been investigated. Results are presented here.
Adrenergic, Cholinergic and Peptidergic Nerve Fibres in Dura Mater Involvement in Headache? (1981)

Nerve fibres containing noradrenaline, acetylcholinesterase, vasoactive intestinal polypeptide and substance P were demonstrated in the dura mater of guinea-pigs using histochemical and immunohistochemical methods. These fibres accompanied blood vessels of all size, indicating a vasomotor role. In addition, some nerve fibres were observed without any obvious relation to the blood vessels. The rich supply of nerve fibres to the various parts of the dura mater may possibly be of importance in the pathogenesis of some types of headache.