gebhart/patrepeval huggingface dataset:
Purification and characterization of an extracellular 29-kilodalton phospholipase C from Listeria monocytogenes (1991)

We purified and characterized an extracellular phospholipase produced by Listeria monocytogenes. This enzyme was separated as a homogeneous protein of 29 kDa by chromatography on DEAE-52 cellulose and Bio-Gel P100 columns. It is a zinc-dependent phospholipase C (PLC) that is mainly active at pH 6 to 7 and expresses lecithinase activity and a weaker sphingomyelinase activity. The exoenzyme also hydrolyzed phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin but not phosphatidylinositol. It was distinct from the 36-kDa phosphatidylinositol PLC produced by L. monocytogenes and from the L. ivanovii sphingomyelinase. The pure protein expressed a weak, calcium-independent hemolytic activity and was not toxic in mice. Western immunoblot analysis using a rabbit immune serum raised against the enzyme showed that all virulent strains of L. monocytogenes tested produced in the culture supernatant a 29-kDa PLC. In contrast, no proteins antigenically related to the 29-kDa PLC were detected in supernatants of L. ivanovii, L. seeligeri, L. innocua, or L. welshimeri. The role in virulence of the 29-kDa PLC specifically produced by L. monocytogenes remains to be established.
Using a Room Metaphor to Ease Transitions in Groupware (2002)

Many groupware systems contain gaps that hinder or block natural social interaction or that does not let people easily move between different styles of work.We believe that the adoption of a room metaphor can ease people's transitions across these gaps, allowing them to work together more naturally.Using the TeamWave Workplace system as an example, we show how particular gaps are removed.First, we ease a person's transition between single user and groupware applications by making rooms suitable for both individual and group activity.Second, people can move fluidly between asynchronous and synchronous work because room artifacts persist.People can leave messages, documents and annotations for others, or work on them together when occupying the room at the same time.Third, we ease the difficulty of initiating real time work by providing people with awareness of others who may be available for real-time interactions, and by automatically establishing connections as users enter a common room.Fourth, we discuss how a technical space can be transformed into a social place by describing how a group crafts meaning into a room.We also argue that a room metaphor's seamless support of everyday activities will foster an environment where groups naturally share their expertise.
Synthesis and Biological Properties of <i>N</i>‐Acetyl‐4‐deoxy‐<scp>D</scp>‐neuraminic Acid (1986)

Abstract N ‐Acetylneuraminic acid ( 1 ) can be transformed into the methyl α‐ D ‐ketoside 2 which, by reaction with methanesulfonyl chloride, yields the corresponding 4‐ O ‐mesylate 3 and the 4,7‐di‐ O ‐mesylate 4 as a by‐product. Compound 3 reacts with Nal giving the 4‐deoxy‐4‐iodo compound 5 with equatorial orientation of the I‐atom. As second product, the dihydrooxazole 6 is produced. Catalytic hydrogenation of 5 is followed by ester cleavage and removal of the isopropylidene group yielding the methyl α‐ D ‐ketoside 8 which affords the title compound, N ‐acetyl‐4‐deoxyneuraminic acid ( 9 ), by reaction with fowl plague virus sialidase. Further biochemical activities of 8 and 9 are reported.
Molecular analysis of the region encoding the lytic system from<i>Oenococcus oeni</i>temperate bacteriophage Ï10MC (1999)

Malolactic fermentation by Oenococcus oeni is a crucial step in wine-making. Oe. oeni phages are thought to be responsible for fermentation failures, yet they have received little attention. After a molecular analysis concerning the phage phi 10MC integration system, this paper focuses on the lytic system. The attP (phage attachment site)-flanking region has been cloned and sequenced. The 1296-bp lysin gene (Lys) was identified in this region. The deduced amino acid sequence showed classical structural features of phage lysins, and this gene product expressed in Escherichia coli had a lytic activity against Oe. oeni. Downstream of Lys, a second ORF was present (P163). According to its amino acid sequence and the location of its gene, the product could be the phi 10MC holin. This study shows that the genomic organization of phage phi 10MC attP-flanking regions is very similar to that of other lactic acid bacteriophages.
Mycosporine-Like Amino Acids: Relevant Secondary Metabolites. Chemical and Ecological Aspects (2011)

Taxonomically diverse marine, freshwater and terrestrial organisms have evolved the capacity to synthesize, accumulate and metabolize a variety of UV-absorbing substances called mycosporine-like amino acids (MAAs) as part of an overall strategy to diminish the direct and indirect damaging effects of environmental ultraviolet radiation (UVR). Whereas the enzymatic machinery to synthesize MAAs was probably inherited from cyanobacteria ancestors via the endosymbionts hypothesis, metazoans lack this biochemical pathway, but can acquire and metabolize these compounds by trophic transference, symbiotic or bacterial association. In this review we describe the structure and physicochemical properties of MAAs, including the recently discovered compounds and the modern methods used for their isolation and identification, updating previous reviews. On this basis, we review the metabolism and distribution of this unique class of metabolites among marine organism.
Intramolecular Singlet and Triplet Energy Transfer in a Ruthenium(II) Diimine Complex Containing Multiple Pyrenyl Chromophores (1999)

We report the synthesis and the photophysical properties of UV light-harvesting arrays constructed around a [Ru(bpy)3]2+ core (bpy = 2,2‘-bipyridine) bearing one and three pyrenyl units in the periphery. The free ligand containing the pyrenyl unit, 4-methyl-4‘-(2-hydroxyethylpyrenyl)-2,2‘-bipyridine, displays an intense emission band centered near 400 nm with a lifetime of 264 ns, characteristic of singlet pyrene emission. The complexes [Ru(dmb)2(4-methyl-4‘-(2-hydroxyethylpyrenyl)-2,2‘-bipyridine)](PF6)2, where dmb is 4,4‘-dimethyl-2,2‘-bipyridine, and [Ru(4-methyl-4‘-(2-hydroxyethylpyrenyl)-2,2‘-bipyridine)3](PF6)2 exhibit visible emission characteristic of the [Ru(bpy)3]2+ unit, regardless of excitation wavelength. The singlet emission from the pyrene chromophores is almost quantitatively quenched by the metal-to-ligand charge transfer (MLCT) states of each respective Ru(II) complex resulting in the observation of sensitized MLCT-based emission. On account of the energetic proximity between the 3MLCT states and the 3pyrene states, a long-lived 3MLCT emission is observed which decays with the same first-order lifetime as the pyrene triplet states in deaerated CH3CN. In deaerated CH3CN, the bichromophoric system displays a lifetime of 2.96 μs, whereas the tetrad complex exhibits a lifetime of 9.0 μs. The results are indicative of excited-state equilibrium between the 3MLCT and 3pyrene states. Our findings demonstrate rapid and efficient singlet−singlet energy transfer through the antenna effect whereas the reversible triplet−triplet energy transfer processes help sustain long-lived MLCT excited states.
Modeling solitary waves on nonlinear transmission lines (1995)

Practical transmission lines have losses, and physical nonuniformities that can result in a destructive distortion of the rise and fall times of digital signals. The main problem is dispersion, in which the higher frequency wave components travel faster than the lower frequency components, resulting in a severe distortion that cannot be corrected with simple amplification, In contrast to this complex situation, solitary waves tend to assume a given shape and automatically maintain their shape until they approach the end of their life. This paper shows that an accurate model is possible for nonideal lines that support solitary waves, allowing their behavior to be predicted to an arbitrary precision.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Expression of the 180-kD Ribosome Receptor Induces Membrane Proliferation and Increased Secretory Activity in Yeast (1999)

Expression of the canine 180-kD ribosome receptor (p180) in yeast cells resulted in a marked proliferation of intracellular membranes. The type of membranes observed varied with the expression of specific portions of p180. Rough membranes predominated when the ribosome binding domain of p180 was present, whereas expression constructs lacking this region resulted in smooth membranes. Northern analysis indicated that expression of the NH(2)-terminal 767 amino acids (DeltaCT), which include the ribosome binding domain, upregulated the transcription and translation of genes involved in exocytosis. The membranes that were proliferated were functional as these cells overcame a temperature-sensitive translocation defect. Most significantly, cells that overexpressed DeltaCT and proliferated rough endoplasmic reticulum exhibited severalfold higher levels of secretion of an ectopically expressed secretory protein. We conclude that p180 expression triggers a cascade of events leading to an increase in secretory potential akin to the terminal differentiation of mammalian secretory cells and tissues.
The Cold-insoluble Globulin of Human Plasma (1970)

Abstract The cold-insoluble globulin (CI-globulin) of human plasma has been highly purified. Starting with Fraction I-1, or plasma cryoprecipitate, 2.1 m glycine fractionation (15°) precipitated mainly fibrinogen; concentration of supernatant CI-globulin-enriched material (16% ethanol, -4°) was carried out prior to final purification by chromatography on di-ethylaminoethylcellulose. Chromatographically purified CI-globulin contained no detectable fibrinogen and was homogeneous upon ultracentrifugation (s20,w0 = 12.3 S); only trace amounts of NH2-terminal amino acids were detectable. CI-globulin migrated as a fast β-globulin in agarose gel or cellulose acetate strip electrophoresis. In immunoelectrophoretic experiments, CI-globulin formed a single precipitin arc against an anti-CI-globulin serum. There was no detectable lipid, fibrin-stabilizing factor (Factor XIII), anti-hemophilic Factor B (Factor IX), plasminogen, plasmin, or thrombin inhibitory activity; low levels of anti-hemophilic factor A (Factor VIII) activity were present. There was no evidence of any alteration of the electrophoretic, ultracentrifugal, or NH2-terminal characteristics of CI-globulin following thrombin treatment or heating to 56° for 5 min. The plasma CI-globulin level, estimated by antigen-antibody crossed electrophoresis, was 0.33 g per liter (range = 0.26 to 0.38, n = 12). The level in serum, 0.20 g per liter (range = 0.14 to 0.30, n = 11), was consistently lower (19 to 52%), presumably attributable to CI-globulin incorporation or occlusion in the fibrin clot. After removal of plasma cryoprecipitate and Cohn Fraction I, supernatant CI-globulin levels were reduced by 59 and 79%, respectively.
Demonstration of a fibre-optic sensing technique for the measurement of moisture absorption in concrete (2006)

A fibre-optic-based humidity sensor has been developed and used for the measurement of moisture absorption in concrete. The sensor was fabricated using a fibre Bragg grating (FBG) coated with a moisture sensitive polymer. To investigate the use of this sensing technique for the detection of moisture ingress in concrete, the sensor was embedded in various concrete samples of different water to cement ratios which were then immersed in a water bath. A direct indication of the humidity level within a sample is given by the shift of the Bragg wavelength caused by the expansion of the humidity-sensitive material coated on the fibre. The sensor itself exploits the inherent characteristics of the FBG, with its operation being based on the strain effect induced in the Bragg grating, through the swelling of the polymer coating. It was found that optical-fibre-based humidity sensors of this type form a basis for determining the changes in the moisture content in different concrete samples, indicating potential new applications of the sensor system to ensure the integrity of civil engineering structures in which they are used.
Techniques for the Transformation of Logic Equations (1974)

A generalized DeMorgan's theorem is presented that can be applied to Boolean equations with any number of complementations. The known form of the DeMorgan's theorem is a special case of the generalized theorem with one inversion. This new theorem simplifies and generalizes the transformation of Boolean functions to their equivalent sum of product forms.
A Self-Normalization Reconstruction Technique for PET Scans Using the Positron Emission Data (2012)

Positron emission tomography (PET) image quality in both clinical and preclinical environments highly depends on an accurate knowledge of the detector hardware to correct for image quality degrading effects like gain, temperature, and photon detection efficiency variations of the individual crystals. In conventional PET systems some of these variations are typically corrected using a dedicated calibration scan in which the scanner performance for a well-known activity source is measured. We propose an alternative method for estimating the relative sensitivity of each detector pixel using the coincidences as well as the singles emission data of each PET scan. The overall idea is to compare the total sum of all measured single photons before coincidence processing in each crystal with a steadily low-frequent distribution that can normally be expected. Both the estimated activity and the estimated detector sensitivity are simultaneously improved by using an extended iterative reconstruction scheme. This way we ensure the use of an optimal calibration correction (with the exception of a global factor) for each data set, even if the scanner performance has changed between two scans. Data measured with a preclinical PET scanner (HYPERIon-I) which uses analog silicon photomultipliers in combination with a custom-made ASIC shows a significant increase of image quality and homogeneity using the proposed method.
Can Cold or Heat Shock Improve Skeletal Myoblast Engraftment in Infarcted Myocardium? (2005)

These data confirm the high death rate of in-scar transplanted myoblasts, demonstrate the ability of those that survive to proliferate and differentiate along the myogenic pathway but do not support the efficacy of either Cryo or HS for increasing the ultimate magnitude of myoblast engraftment.
Synthesis of the New Tricyclic System. Thieno[3',2':3,4]pyrido[1,2-a]pyrazin-4-one (1984)

The new t r i c y c l i c system thieno [3'Za,: 3,4] p y r i d o ( 1.2-a)pyrazin-4-one, a thiophenic i s o s t e r e of t h e heterocyclic system pyrazino-(1.2-a)isoquinolin-4-onei s synthesised by c y c l i s a t i o n i n a c i d i c medium from 4-acyl-6-hydroxy-l-!~-(2-thienyl)ethy!ipiperazin-2-one.Those hydroxyimides r e s u l t from s e l e c t i v e reduction of corresponding piperazine-2,6-diones.I n a recent paper1, we described an o r i g i n a l synthesis of praziquantel.a very potent schistosomicide, t h e s t r u c t u r e o f which p o i n t s t o the pyrazino ( 1 , 2 -a ) isoquinolin-4-one system (1).We present 2 i n t h i s paper, t h e synthesis of a thiaphenic i s o s t e r e of praziquantel and some analogs, the s t r u c t ur e o f which belongs t o the new h e t e r o c y c l i c system thieno[3'2',:3,4] p y r i d o ( 1 , ?-a ) pyrazin-4-one 1 -
Using Zinc Finger Nucleases for Efficient and Heritable Gene Disruption in Zebrafish (2010)

While the experimental tools developed for zebrafish have continued to advance the organism as a laboratory model, techniques for reverse genetics remain somewhat limited in scope. Zinc finger nucleases (ZFNs), chimeric fusions between DNA-binding zinc finger proteins and the non-specific cleavage domain of the FokI endonuclease, hold great promise for targeted mutagenesis in zebrafish, as demonstrated by two recent publications (Doyon et al., 2008, Nat Biotechnol. 26, 702-708; Meng et al., 2008, Nat Biotechnol. 26, 695-701). Because ZFNs can be designed to recognize a unique sequence in the genome, they can specifically bind and cleave a target locus, creating a double-strand break (DSB) that is repaired by one of two major DNA repair pathways. Repair by one of these pathways, non-homologous end joining, is often mutagenic, allowing one to screen for induced mutations in the target locus. By injecting into zebrafish embryos RNA encoding ZFNs that target three different loci, two groups have shown that ZFNs work efficiently to induce somatic and germline mutations (reviewed in (3)). We review here protocols for injection of ZFN-encoding mRNA into zebrafish embryos, screening of injected fish for induced mutations, and subsequent recovery of the induced mutations.
Cooperative Spectrum Sensing with Multi-Channel Coordination in Cognitive Radio Networks (2010)

Accurate spectrum sensing is one of the key technologies to enable dynamic spectrum access in cognitive radio networks. Recently cooperative spectrum sensing is proposed as an efficient way to achieve better sensing accuracy. It makes use of multiple nodes to sense a channel and then analyzes their results together to get more accurate results. Several works have been conducted to study this technology and they mostly focus on the cooperation in individual channels. However, cognitive radio networks usually deal with multiple channels, therefore the coordination among multiple channels needs be studied to fully explore the potential of cooperative sensing. In this paper we focus on the coordination among multiple channels in cooperative spectrum sensing. We at first study the theoretical improvement made by multi-channel coordination, then propose a centralized and a distributed algorithm to implement it. The theoretical analysis proves cooperative sensing can be improved significantly if the coordination among multiple channels is considered. To verify our analysis, we measure licensed channels then conduct simulations basing on collected data. The results show that the proposed algorithms can approximate optimal solution very well.
Exploiting social relations for query expansion and result ranking (2008)

Online communities have recently become a popular tool for publishing and searching content, as well as for finding and connecting to other users that share common interests. The content is typically user-generated and includes, for example, personal blogs, bookmarks, and digital photos. A particularly intriguing type of content is user-generated annotations (tags) for content items, as these concise string descriptions allow for reasonings about the interests of the user who created the content, but also about the user who generated the annotations. This paper presents a framework to cast the different entities of such networks into a unified graph model representing the mutual relationships of users, content, and tags. It derives scoring functions for each of the entities and relations. We have performed an experimental evaluation on two real-world datasets (crawled from deli.cio.us and Flickr) where manual user assessments of the query result quality show that our unified graph framework delivers high-quality results on social networks.
Biodegradability and Molecular Composition of Dissolved Organic Nitrogen in Urban Stormwater Runoff and Outflow Water from a Stormwater Retention Pond (2016)

Dissolved organic nitrogen (DON) can be a significant part of the reactive N in aquatic ecosystems and can accelerate eutrophication and harmful algal blooms. A bioassay method was coupled with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) to determine the biodegradability and molecular composition of DON in the urban stormwater runoff and outflow water from an urban stormwater retention pond. The biodegradability of DON increased from 10% in the stormwater runoff to 40% in the pond outflow water and DON was less aromatic and had lower overall molecular weight in the pond outflow water than in the stormwater runoff. More than 1227 N-bearing organic formulas were identified with FT-ICR-MS in the stormwater runoff and pond outflow water, which were only 13% different in runoff and outflow water. These molecular formulas represented a wide range of biomolecules such as lipids, proteins, amino sugars, lignins, and tannins in DON from runoff and pond outflow water. This work implies that the urban infrastructure (i.e., stormwater retention ponds) has the potential to influence biogeochemical processes in downstream water bodies because retention ponds are often a junction between the natural and the built environment.
Chitosan based antimicrobial films for food packaging applications (2008)

Abstract Antimicrobial packaging is one of the most promising active packaging systems. Antimicrobial packaging is the packaging system that is able to kill or inhibit spoilage and pathogenic microorganisms that are contaminating foods. A tremendous effort has been made over the last decade to develop and test films with antimicrobial properties to improve food safety and shelf life. For food preservation, chitosan films are very effective. Chitosan has widely been used in antimicrobial films, to provide edible protective coating, dipping and spraying for the food products due to its antimicrobial properties. Chitosan can be formed into fibers, films, gels, sponges, beads or nanoparticles. Chitosan films have been used as a packaging material for the quality preservation of a variety of food. Chitosan has great potential for a wide range of applications due to its biodegradability, biocompatibility, antimicrobial activity, non-toxicity and versatile chemical and physical properties. The present review outlines the preparation and antimicrobial activity of chitosan based films.
Analytical Modeling of 3D Stacked IC Yield from Wafer to Wafer Stacking with Radial Defect Clustering (2014)

Current yield estimation models for 3D Stacked ICs manufactured using wafer-to-wafer stacking ignore defect clustering and assume a uniform distribution of defective dies on each wafer. Recent experiments based on carefully simulated wafer defect maps and validated by actual silicon data have shown that the clustering of manufacturing defects can have a major impact on actual 3D-SIC yields. Traditionally modeled yield estimates can be pessimistic by as much as 50%. However, no new analytical models have as yet been developed to account for this defect clustering effect. We present and validate the first 3D-SIC yield model that incorporates the impact of the radial clustering of defects on wafers. This major contributor to defect clusters on wafers can be directly included in analytical models using a few easy to measure spatial measures of wafer yield. Our new model is validated using synthesized wafer defect maps from proven radial defect models, as well as actual silicon wafer defect map data. The results presented here show that the models accurately capture much of the impact of defect clustering on 3D-SIC yields, and can allow the cost trade-offs associated with 3D-SIC manufacturing to be more easily and accurately estimated early in the design phase.
Love's Labour's Lost: The Failure of Traditional Selection Practice in the Acquisition of Humanities Electronic Texts. (2000)

THELIBRARY LITERATURE FROM THE LATE nineteenth century to the present offers numerous rational well-intentioned guides to the selection of materials.Yet, collection development policies and lists of selection criteria are inadequate for humanities electronic texts.Libraries, humanities disciplines, and electronic texts are too complex for any rigid approach to acquisition.In order to meet goals and satisfy users, libraries must abandon traditional practices and adopt new ones for these resources.