gebhart/patrepeval huggingface dataset:
Ordered Nanopattern Arrangement of Gold Nanoparticles on β-Sheet Peptide Templates through Nucleobase Pairing (2011)

We have demonstrated a unique method for rational arrangement of gold (Au) nanoparticles on a β-sheet peptide template through nucleobase pairing. For the template, the 16-mer peptide 1 was synthesized, which is based on an alternating amphiphilic sequence of Asp-Leu. Here Leu at the sixth position is replaced by thymine-modified Lys, and a polyethylene glycol chain is introduced to the C-terminus. The surface of Au nanoparticles was modified with the complementary adenyl group. Peptide 1 formed a stable β-sheet monolayer at the air/water interface under an appropriate surface pressure. The monolayer film transferred onto a mica surface by the Langmuir-Blodgett method showed a linearly striped pattern with 6.1 nm average stripe width and 6 nm average interval between stripes, derived from β-sheet assembly. The adenine-bound Au nanoparticles were successfully immobilized on the thymine-bound template through a complementary adenine-thymine hydrogen bonding pair. Interestingly, linear assembly structures of the Au nanoparticles were observed, thus being successfully reproduced by the original striped pattern of the template of 1. Our method might readily fabricate Au materials with our desirable 2D pattern through fine-tuning of β-sheet sequence and nucleobase position.
A dielectric affinity microbiosensor (2010)

We present an affinity biosensing approach that exploits changes in dielectric properties of a polymer due to its specific, reversible binding with an analyte. The approach is demonstrated using a microsensor comprising a pair of thin-film capacitive electrodes sandwiching a solution of poly(acrylamide-ran-3-acrylamidophenylboronic acid), a synthetic polymer with specific affinity to glucose. Binding with glucose induces changes in the permittivity of the polymer, which can be measured capacitively for specific glucose detection, as confirmed by experimental results at physiologically relevant concentrations. The dielectric affinity biosensing approach holds the potential for practical applications such as long-term continuous glucose monitoring.
A simple model for the swelling of polymer networks (1993)

The Flory–Rehner approach to the solvent swelling of polymer networks is modified so as to abandon the affine deformation assumption. Instead, it is assumed that swelling occurs by a process of disinterspersion of cross-link junctions, and relationships between chain expansion and segment concentration are established using the ideas of de Gennes. Using this approach, we also examine osmotic deswelling, aspects of phase equilibria, and the maximum observed in differential swelling measurements.
Si based tunnel field effect transistors: Recent achievements (2013)

Recent achievements of silicon based tunnel field effect transistors (TFETs) and remaining major challenges are overviewed. Particular emphasis is placed on the band to band tunneling (BTBT) junctions, the heart of the device. Dopant segregation from ion implanted ultrathin silicide contacts proved as viable method to achieve steep tunneling junctions. This avoids defect generation by direct implantation into the junction and thus minimizes the risk of trap assisted tunneling. The method was applied to strained silicon, specifically to nanowire array transistors. This enabled the realization of TFETs with fairly high currents and first complementary TFET inverters with sharp transitions and good static gain, even at very low drain voltages of V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DD</sub> = 0.2 V. These achievements suggest a considerable potential of TFETs for ultralow power applications. Some novel concepts, e.g. to enlarge the tunneling area by “line tunneling”, are addressed. A benchmarking figure summarizes the present status.
Experiment of Tension-compression Fatigue and Damage for Asphalt Mixtures (2013)

A tension-compression beam fatigue test under continuous sine wave alternating loading for AC-13 was conducted to understand fatigue damage characteristics of an actual asphalt pavement structure under tension and compression stresses. Tension-compression fatigue damage characteristics of asphalt mixtures were investigated using phenomenology based on basic theory of damage mechanics. Tension-compression fatigue test method and influencing factors were introduced; and tension-compression fatigue equation was established via fatigue test results. A tension-compression fatigue damage model was developed based on the damage variable defined by elastic modulus. Damage parameters were determined by fitting fatigue test data. Tension-compression fatigue damage evolution equation regarding stress level was constructed. Results show the following. (1) Fatigue damage parameters α and β increase with stress level; and relationship between damage parameters and stress level is linear. (2) Tension-compression fatigue damage evolution has approximately three stages: damage initiation, stable growth, and unstable failure. (3) The greater the nominal stress level is, the lower the curve of the damage evolution curve is, and the less fatigue damage evolution speed varies with life radio.
Decomposition of copper(II) sulfate pentahydrate: A sequential gravimetric analysis (1979)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDecomposition of copper(II) sulfate pentahydrate: A sequential gravimetric analysisArlo D. Harris and Lee H. Kalbus Cite this: J. Chem. Educ. 1979, 56, 6, 417Publication Date (Print):June 1, 1979Publication History Received3 August 2009Published online1 June 1979Published inissue 1 June 1979https://doi.org/10.1021/ed056p417RIGHTS & PERMISSIONSArticle Views1850Altmetric-Citations12LEARN 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 InReddit PDF (1 MB) Get e-Alertsclose Get e-Alerts
Novel Syn Intramolecular Pathway in Base-Catalyzed 1,2-Elimination Reactions of β-Acetoxy Esters (2007)

As part of a comprehensive investigation of electronic effects on the stereochemistry of base-catalyzed 1,2-elimination reactions, we observed a new syn intramolecular pathway in the elimination of acetic acid from beta-acetoxy esters and thioesters. 1H and 2H NMR investigation of reactions using stereospecifically labeled tert-butyl (2R*,3R*)-3-acetoxy-2,3-2H2-butanoate (1) and its (2R*,3S*) diastereomer (2) shows that 23 +/- 2% syn elimination occurs. The elimination reactions were catalyzed with KOH or (CH3)4NOH in ethanol/water under rigorously non-ion-pairing conditions. By contrast, the more sterically hindered beta-trimethylacetoxy ester produces only 6 +/- 1% syn elimination. These data strongly support an intramolecular (Ei) syn path for elimination of acetic acid, most likely through the oxyanion produced by nucleophilic attack at the carbonyl carbon of the beta-acetoxy group. The analogous thioesters, S-tert-butyl (2R*,3R*)-3-acetoxy-2,3-2H2-butanethioate (3) and its (2R*,3S*) diastereomer (4), showed 18 +/- 2% syn elimination, whereas the beta-trimethylacetoxy substrate gave 5 +/- 1% syn elimination. The more acidic thioester substrates do not produce an increased amount of syn stereoselectivity even though their elimination reactions are at the E1cb interface.
A performance monitoring system for large computing clusters (2003)

In this paper we describe the architecture of PerfMC, a performance monitoring system for clusters of workstations; a prototype implementation of the architecture is also presented. PerfMC is driven by an XML configuration file, and uses the Simple Network Management Protocol (SNMP) to collect statistics from each networked equipment. The collected data are maintained on the local disk of the monitoring station in a compact format, and various graphical and statistical analyses can be performed off-line. The monitoring tool embeds an HTTP server which is able to generate various types of graphs from the collected data. Moreover the HTTP server can generate arbitrary XML pages by dynamically applying XSLT stylesheets to an internal XML representation of the cluster's status. The heavy use of XML-based technologies differentiates the proposed approach to traditional monitoring tools.
Light-emitting electrochemical cells using a molten delocalized salt (2002)

The device performances of light-emitting electrochemical cells are improved by adding a room-temperature molten salt (tetrahexylammonium-bis-trifluoro-methyl-sulfonyl imide) directly into the light-emitting layer. For poly(9,9-dihexyl-fluorene-2,7-diyl) with an indium-tin-oxide anode and an aluminum cathode, the power efficiency can be increased by more than one order of magnitude. An even more pronounced effect is observed for poly [2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylenevinylene]. Equally important for both luminescent polymers, the operating voltage is drastically reduced.
Classification of project management tool reviews using machine learning-based sentiment analysis (2019)

Managing the daily responsibilities in an organization is a great task for company administrators. Employing a dedicated project management tool is a great aid in all the phases of project management. With a variety of project management tools available in the market, it is a demanding task to look for a tool appropriate to the needs of the organization. It is an observation by scholars and suggests project management tool users tend to read first the reviews and comments of the product before deciding on the tool they are going to implement. This study facilitates sentiment analysis which can help identify effective and efficient project management tool. Microsoft Office Project is one of the most popular and most reviewed tools for more efficient project and portfolio management. The researchers manually extracted data from various websites containing comments and reviews from different users or reviewers. Machine learning-based-approach using RapidMiner was utilized to analyze the collected data from the web reviews. Sentiment analysis from MS Project reviews was applied using supervised learning K-nearest neighbor (KNN). The first level of classification involved classifying statements as "satisfied" and "dissatisfied." The second level of classification involved clustering sentiments as cost, experience, task, support and interface. Statements classified as satisfied is greater than dissatisfied. The best features to apply when classifying the PM tool reviews dataset are using stopwords, length, stemming and trigram.
Purification and characterization of hepatic oligosaccharyltransferase. (1995)

Oligosaccharyltransferase transfers a preformed oligosaccharide from a dolichol carrier molecule to specific asparaginyl residues of proteins synthesized in the endoplasmic reticulum. We have isolated a protein complex with this activity from chicken liver microsomes with 850 fold purification. The purification procedure involved removal of peripheral and lumenal proteins, solubilization of the membranes by non-ionic detergent and glycerol gradient centrifugation. The complex was purified further by ion-exchange and gel filtration chromatography. SDS-PAGE analysis of the final preparation revealed 3 major protein bands, two bands with an approximate molecular weight of 65-kDa and one band of approximately 50-kDa. Endoglycosidase H digestion of the purified subunits indicated the presence of carbohydrate on the 65-I subunit. No carbohydrate was detected in the 65-II subunit or the 50-kDa subunit. Amino acid sequence analysis of the intact protein subunits and internal peptides generated by cynogen bromide digestion, identified the 65-kDa subunits as ribophorin I and II. The 50-kDa subunit has 25% homology with a yeast membrane protein (Wbplp) which is essential for oligosaccharyltransferase activity in Saccharomyces cerevisiae.
Development of Acoustic Emission Monitoring System for Fine Machining - Application to Cutting State Monitoring in a Fine Fixed-abrasive Machining - (2005)

In case of fine machining processes, the cutting state monitoring by a skilled operator is impossible because the physical changes generated during fine machining are very weak. To realize the high efficient and precise fine machining, it is necessary to develop the sensor based monitoring system which is able to detect the fine changes of cutting state. In this paper, the fine acoustic emission monitoring system is developed to monitor the state of the fine machining process. The developed system consists of the AE sensor and the AE signal processing unit. And this has the high-sensitivity and bandwidth which can detect fine AE signal generated during fine machining process. In order to investigate the feasibility of the developed system, evaluation experiments were performed in the fine fixed-abrasive machining processes such as polishing and glass ferrule slicing. Experimental results show that the developed monitoring system possesses an excellent real-time monitoring capability at fine machining processes.
Effect of Dilauroylphosphatidylcholine on the Acrosome Reaction and Subsequent Penetration of Bull Spermatozoa into Zona-Free Hamster Eggs (1986)

Incubation of bull sperm with liposomes made with phosphatidylcholine (PC) containing fatty acyl chains of either 10 (PC10) or 12 (PC12) carbons resulted in greater than 90% of the sperm exhibiting an acrosome reaction (AR) within 15 min. Liposomes of PC10 rapidly destroyed sperm motility while PC12 acrosome-reacted sperm remained motile for several h. Liposomes of PC with greater than or equal to 14-carbon fatty acyl chains had no effect on the AR or motility of sperm. The AR was not induced by lysophospholipids, because lysophospholipids were not detected in the PC liposomes, and the AR did not occur when lysophospholipids were tested at the same concentration as PC12. The concentration of PC12 necessary to induce maximal numbers of acrosome-reacted sperm varied with the concentration of sperm. The effect of PC12 on sperm also varied with the ratio of live to dead sperm in a sample. When 3 X 10(6) bull sperm/ml were treated with 0, 10, 20, and 30 microM PC12 for 7 min prior to addition to zona-free hamster eggs, 6, 6, 98, and 77% of the eggs were penetrated, respectively. Lipid concentrations of 0 microM and 10 microM did not affect the AR, whereas higher levels induced the AR in sperm. This procedure can quickly provide acrosome-reacted bull sperm for use with various in vitro fertilization procedures and for assessment of male fertility.
Expression of HLA-A2 antigen in human melanoma cell lines and its role in T-cell recognition. (1991)

Previous studies have suggested that, in human melanoma, expression of HLA-A2 antigen is important for tumor cell recognition by autologous T-lymphocytes. Because of the recent demonstration that expression of HLA Class I antigens may be selectively lost in several human tumors, including melanoma, we derived pairs of tumor infiltrating lymphocytes (TIL) and melanoma cell lines from 4 human lymphocytic antigen (HLA)-A2+ patients with metastatic melanoma. We observed that, although all 4 TIL cultures expressed HLA-A2 antigen, only 2 melanoma cell lines did so. Melanoma cells derived from the other 2 patients showed neither surface expression of the HLA-A2 antigen nor presence of the corresponding mRNA. We also observed some correlation between loss of HLA-A2 expression and level of c-myc transcription. TIL derived from patients whose melanoma cell lines had normal expression of HLA-A2 had a CD8 phenotype and were capable of lysing autologous melanoma cells. Melanoma cell killing was CD3 and major histocompatibility complex Class I restricted in both cases, but HLA-A2 restricted in only one case. On the other hand, TIL derived from the 2 patients whose melanoma cell lines had lost expression of HLA-A2 had a predominant CD4 phenotype and virtually no cytotoxic activity. Preincubation of the HLA-A2 negative melanoma cell lines with alpha- or gamma-interferon did not induce the re-expression of the HLA-A2 antigen. In an attempt to restore HLA-A2 antigen expression in one of the melanoma cell lines that were HLA-A2 negative, we transfected these cells with the HLA-A2 gene subcloned in the pSV2-neo vector. Four transfected clones, with high levels of HLA-A2 antigen expression, were expanded and characterized. Proliferative and cytotoxic activities of TIL against the autologous transfected clones as well as the untransfected parental melanoma cell line were measured and compared. CD4+ TIL showed no difference in the proliferative response to autologous parental and HLA-A2 transfected clones. However, we observed selective recognition of the HLA-A2 expressing clones by autologous cultured peripheral blood lymphocytes (which contained CD8 cells) as well as allogeneic CD8+ TIL with a HLA-A2 restricted pattern of recognition. In contrast, virtually no cytotoxic activity was detected against either parental or HLA-A2 transfected clones. Overall, our data suggest that selective down-regulation of HLA-A2 antigen expression in melanoma cells may represent one of the mechanisms by which tumor cells escape immunological recognition.
Annual ryegrass and volunteer cereal control in lupins using selective post-emergent herbicides (1995)

The relative effectiveness of herbicides from the aryloxyphenoxypropionate (fop) and cyclohexanedione (dim) chemical families for the control of volunteer wheat (Triticum aestivum L.), oats (Avena sativa), triticale (Triticum x Secale) and annual ryegrass (Lolium rigidum Gaud.) in narrow-leafed lupins (Lupinus angustifolius) were evaluated over a 3-year period near Rutherglen in north-eastern Victoria. Herbicides tested included diclofop-methyl, fluazifop-pethyl, haloxyfop, propaquizafop, quizalofop-p-ethyl, clethodim, cycloxydim, sethoxydim, and mixes of fluazifop-p-ethyl + diclofop-methyl, and fluazifop-pethyl + sethoxydim. Effective grass control needed to prevent disease carryover is defined as greater than 98%. Haloxyfop at 78 g a.i./ha and clethodim at 120 g a.i./ha consistently gave greater than 98% control of all target species. Quizalofop-p-ethyl at 12 g a.i./ha gave greater than 98% control of volunteer cereals but annual ryegrass control ranged from 83.7 to 44.1%. Cycloxydim at 100 g a.i./ha produced similar oat and ryegrass control to that of 563 g a.i./ha diclofop-methyl. Sethoxydim at 93 g a.i./ha, gave significantly (P < 0.05) better control of annual ryegrass than the recommended rates of diclofop-methyl, fluazifop-p-ethyl and propaquizafop. The addition of 47 g a.i./ha sethoxydim to 32 g a.i./ha fluazifop-p-ethyl significantly improved ryegrass control than low rates of fluazifop-p-ethyl alone.
Negative Differential Conductance and Hot Phonons in Suspended Nanotube Molecular Wires (2005)

Freely suspended metallic single-walled carbon nanotubes (SWNTs) exhibit reduced current carrying ability compared to those lying on substrates, and striking negative differential conductance at low electric fields. Theoretical analysis reveals significant self-heating effects including electron scattering by hot nonequilibrium optical phonons. Electron transport characteristics under strong self-heating are exploited for the first time to probe the thermal conductivity of individual SWNTs (approximately 3600 W m-1 K-1 at T=300 K) up to approximately 700 K, and reveal a 1/T dependence expected for umklapp phonon scattering at high temperatures.
Diagnosis of enterovirus and rhinovirus infections by RT-PCR and time-resolved fluorometry with lanthanide chelate labeled probes (1999)

Detection of enteroviruses and rhinoviruses has traditionally been based on laborious and time-consuming virus isolation. Recently, rapid and sensitive assays for detecting enterovirus and rhinovirus genomic sequences by reverse transcription-polymerase chain reaction (RT-PCR) have been introduced. An RT-PCR assay is described that amplifies both enteroviral and rhinoviral sequences, followed by liquid-phase hybridization carried out in a microtiter plate format. In the hybridization assay, amplicons are identified by enterovirus- or rhinovirus-specific probes carrying lanthanide chelate labels, which can be detected simultaneously by time-resolved fluorometry. The sensitivity and specificity of the RT-PCR-hybridization method were evaluated with a representative collection of enteroviruses and rhinoviruses and tested further its applicability to the clinical setting with cerebrospinal fluid samples and nasopharyngeal aspirates. The RT-PCR assay amplified all enteroviruses and rhinoviruses tested, and all but one amplicon gave a positive result in the subsequent hybridization assay. The RT-PCR-hybridization method was more sensitive than virus isolation for the detection of enteroviruses and rhinoviruses in the clinical samples. High sensitivity, rapidity, and easy performance make the assay suitable for the routine diagnosis of enterovirus and rhinovirus infections.
Identification of a Glycosaminoglycan-binding Site in Chemokine Macrophage Inflammatory Protein-1α (1997)

Chemokines bind to receptors of the seven-transmembrane type on target cells and also bind to glycosaminoglycans (GAGs), including heparin. In this study, we have sought to identify structural motifs mediating binding of the beta-chemokine macrophage inflammatory protein-1alpha (MIP-1alpha) to GAGs. Alignment of beta-chemokine amino acid sequences revealed the presence of several highly conserved basic amino acids, and molecular modeling predicted that the side chains of three of the basic amino acids fold closely together in MIP-1alpha. Site-directed mutagenesis was used to change the conserved basic residues in MIP-1alpha to alanines, and both wild-type and mutant proteins were produced in a transient COS cell expression system. Wild-type MIP-1alpha bound to heparin-Sepharose, while three of the mutants, R18A, R46A, and R48A, failed to bind. Mutant K45A eluted from heparin-Sepharose at lower NaCl concentrations than wild type, while the binding of K61A, with a mutation in the C-terminal alpha-helix, was indistinguishable from that of the wild-type protein. To determine whether GAG-binding capacity is required for receptor binding and cell activation, we performed competition radioligand binding and calcium mobilization experiments using one of the non-heparin-binding mutants, R46A. R46A bound as efficiently as wild-type MIP-1alpha to CCR1 and was equally active in eliciting increases in intracellular free calcium concentrations. Our data define a GAG binding site in MIP-1alpha consisting of three noncontiguous basic amino acids and show that the capacity to bind to GAGs is not a prerequisite for receptor binding or signaling in vitro.