gebhart/patrepeval huggingface dataset:
Antisense inhibition of the GDP‐mannose pyrophosphorylase reduces the ascorbate content in transgenic plants leading to developmental changes during senescence (1999)

GDP-mannose pyrophosphorylase (GMPase, EC 2.7.7.22) catalyses the synthesis of GDP-D-mannose and represents the first committed step in the formation of all guanosin-containing sugar nucleotides found in plants which are precursors for cell wall biosynthesis and, probably more important, the synthesis of ascorbate. A full-length cDNA encoding GMPase from S. tuberosum was isolated. Transgenic potato plants were generated in which the GMPase cDNA was introduced in antisense orientation to the 35S promoter. Transformants with reduced GMPase activity were selected. Transgenic plants were indistinguishable from the wild-type when held under tissue culture conditions, however, a major change was seen 10 weeks after transfer into soil. Transgenic plants showed dark spots on leaf veins and stems with this phenotype developing from the bottom to the top of the plant. In case of the line with the strongest reduction, all aerial parts finally dried out after 3 months in soil, in contrast to the wild-type plants which did not start to senesce at this time. This coincides with a reduction of ascorbate contents in the transgenic plants, which is in agreement with the recently proposed pathway of ascorbate biosynthesis. Furthermore, leaf cell walls of the transgenic potato plants had mannose contents that were reduced to 30-50% of the wild-type levels, whereas the composition of tuber cell walls was unchanged. The glycosylation pattern of proteins was unaffected by GMPase inhibition, as studied by affinoblot analysis.
CramÉr-Rao Bounds for Direction Finding by an Acoustic Vector Sensor Under Nonideal Gain-Phase Responses, Noncollocation, or Nonorthogonal Orientation (2009)

An acoustic <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">vector</i> -sensor (also known as vector-hydrophone in underwater applications) is composed of two or three spatially collocated but orthogonally oriented acoustic <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">velocity</i> sensors, plus possibly a collocated acoustic <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">pressure</i> sensor. Such an acoustic vector sensor is versatile for direction-finding, due to its azimuth-elevation spatial response's independence from the incident source's frequency, and bandwidth. However, previously unavailable in the open literature is how the acoustic vector sensor's far-field direction-of-arrival estimates may be adversely affected by any unknown nonideality in the acoustic vector sensor's gain response, phase response, collocation, or orthogonal orientation among its constituent velocity sensors. This paper pioneers a characterization of how these various unknown nonidealities degrade direction-finding accuracy, via Cramer-Rao bound analysis.
Reinforcement of poly(dimethylsiloxane) networks by blended andin-situgenerated silica fillers having various sizes, size distributions, and modified surfaces (1999)

Elastomeric networks of poly(dimethylsiloxane) (PDMS) were reinforced with silica particles introduced in two rather different ways. The first was by the simple blending of separately-prepared particles into hydroxyl-terminated PDMS chains that were subsequently end-linked, and the second was by in-situ precipitation through the catalyzed "sol-gel" hydrolysis and condensation of a tetraalkoxysilane. Both approaches permitted control of particle sizes and particle-size distributions. Strongly bimodal size distributions in which there were equal weights of small and large particles were of particular interest, and were achieved in the in-situ approach by using two consecutive steps for generating the two sizes of particles. In addition, some in-situ generated particles were treated to make their surfaces more hydrophobic using co-hydrolyses of dialkoxysilanes with the tetraalkoxysilane. X-ray scattering measurements and electron microscopy were used to characterize the particles and their dispersion within the PDMS matrix. In the in-situ approach, an increased amount of catalyst gave larger particles, but in smaller amounts. It also gave better dispersions, both with regard to the particles within the matrix in general, and in the mixing of the two sizes of particles amongst themselves. The resulting composites were also characterized with regard to their mechanical properties in elongation, both in continuous extension and in near-equilibrium measurements. In the latter case, the extents of stress relaxation were also measured and found to be smaller for the in-situ reinforced systems. The bimodal size distributions did not give mechanical properties superior to those of the unimodal ones, with most of the improvements in mechanical properties coming from the smaller particles. The surface-modified silica particles, however, did seem to give improved mechanical properties, presumably through stronger polymer-filler interfacial interactions.
Multicore made simple (2009)

Chips base on Intel's Larrabee architecture aren't on the shelves yet, but the design is already a hot property because it promises to beat the chips that game designers now use to model graphics.
Optimization of Atom Transfer Radical Polymerization Using Cu(I)/Tris(2-(dimethylamino)ethyl)amine as a Catalyst (2000)

The optimization of the synthesis of homopolymers from n-butyl acrylate (BA), styrene (Sty), and methyl methacrylate (MMA), using copper-based atom transfer radical polymerization (ATRP) with tris(2-dimethylaminoethyl)amine (Me6-TREN) as a ligand is reported. Catalyst concentration (copper bromide complexed with 1 equiv of Me6-TREN) as low as 1% relative to initiator (50 ppm in the reaction mixture) was sufficient to successfully prepare well-defined poly(n-butyl acrylate) in bulk. With 50% catalyst to initiator, styrene was polymerized in bulk. The deactivator species had poor solubility in nonpolar solvents. Finally, the polymerization of methyl methacrylate with CuBr/Me6-TREN required the use of a high concentration of catalyst and the addition of Cu(II)Cl2 at the beginning of the reaction; the resulting polymers were of higher molecular weight than predicted by theory and had relatively broad molecular weight distributions.
Comparison of Different Diagnostic Criteria for Vascular Dementia (ADDTC, DSM-IV, ICD-10, NINDS-AIREN) (1996)

Our results show that the classification according to different diagnostic guidelines yields rather distinct groups of patients. The reasons responsible for these findings are as follows: (1) different criteria for dementia, (2) limitation to ischemic VD in the ADDTC criteria, (3) no further differentiation of VD into subtypes according to CT or MRI findings (DSM-IV), and (4) the multifactorial etiopathology of VD. Major diagnostic difficulties ensue from the very frequent cases with white matter lesions, since their etiology and classification remain widely unknown.
Following Charge Separation on the Nanoscale in Cu2O–Au Nanoframe Hollow Nanoparticles (2011)

Cu(2)O-Au nanoframes with different nanolayer thicknesses of Cu(2)O were prepared, and their photocatalytic properties in aqueous solutions were studied. Cu(2)O semiconductor excitation leads to electron-hole separation. In aqueous solution, the hole is known to oxidize water to produce hydroxyl radicals whose concentration (and that of the holes) can be monitored by the rate of the degradation of dissolved methylene blue dye. The exciton lifetime is determined by femtosecond techniques and is determined by electron-hole recombination which depends on the rates of a number of competing processes such as, electron or hole transfer to an acceptor such as a gold nanoframe and/or the electron or hole trapping processes at the Cu(2)O-Au nanoframe interface. We measured the exciton lifetime as a function of the average Cu(2)O-Au layer separation. A good correlation was found between the rate of the photocatalytic degradation of methylene blue and the exciton lifetime. The exciton lifetime is found to increase as the Cu(2)O thickness is increased. This leads to an increase in the electron-hole separation time and thus an increase in the hole (and so the hydroxyl radical) concentration leading to an observed enhanced rate of the dye degradation.
Role of Charge and Hydrophobic Interactions in the Action of Bactericidal/Permeability-increasing Protein of Neutrophils on Gram-negative Bacteria (1983)

We have recently provided evidence suggesting that the action of purified cationic bactericidal/permeability-increasing protein (BPI) from neutrophils on susceptible gram-negative bacteria requires saturation binding to negatively charged surface sites (Weiss, J., S. Beckerdite-Quagliata, and P. Elsbach, 1980, J. Clin. Invest., 65: 619-628.)We now show that this charge interaction is necessary but not sufficient to produce the effects of BPI on the envelope and on viability. By altering the hydrophobic properties of the bacterial (outer) membrane, it is possible to separate saturation binding from the biological action of BPI, indicating that steps beyond surface binding are needed for the antibacterial action. Outer membrane properties were modified by (a) reducing temperature during BPI-Escherichia coli interaction; (b) growing E. coli at 42 degrees C to increase the saturated fatty acid content of membrane phospholipids; and/or (c) using smooth E. coli with a natively less fluid outer membrane. Hydrophobic interaction chromatography on phenyl-Sepharose and measurement of sensitivity to the hydrophobic antibiotic rifampicin were used to monitor the changes in hydrophobic properties of the bacterial outer membrane produced by these manipulations. Nearly all BPI can be removed from the bacterial surface by 80 mM MgCl(2) or by trypsin. At 37 degrees C, removal of BPI results in repair of the envelope alterations, but viability is irreversibly lost, even when Mg(2+) is added after only 15 s of exposure of the bacteria to BPI. However, under conditions of reduced outer membrane hydrophobicity, when saturation binding still occurs within 30 s, E. coli can be rescued by addition of Mg(2+) after up to 5-min exposure to BPI, indicating retardation of postbinding steps. We conclude that after initial binding BPI must enter into a hydrophobic interaction with the outer membrane in order to produce its antibacterial effects. These postbinding events reversibly mediate the membrane perturbations and irreversibly trigger the bactericidal action of BPI.
Central antitussive activity of the NK1 and NK2 tachykinin receptor antagonists, CP‐99,994 and SR 48968, in the guinea‐pig and cat (1997)

1. The purpose of this study was to investigate the antitussive activity and sites of action of the NK1 and NK2 tachykinin receptor antagonists, CP-99,994, SR 48968, and the racemate of SR 48968, SR 48212A in the cat and guinea-pig. 2. Guinea-pigs were dosed subcutaneously (s.c.) with CP-99,994, SR 48212A or SR 48968 one hour before exposure to aerosols of capsaicin (0.3 mM) to elicit coughing. Coughs were detected with a microphone and counted. 3. Intracerebroventricular (i.c.v.) cannulae were placed in the lateral cerebral ventricles of anaesthetized guinea-pigs. Approximately one week later, the animals were dosed with CP-99,994 or SR 48212A (i.c.v.) and exposed to aerosols of capsaicin (0.3 mM) to elicit coughing. 4. Cough was produced in anaesthetized cats by mechanical stimulation of the intrathoracic trachea and was monitored from electromyograms of respiratory muscle activity. Cannulae were placed for intravenous (i.v.) or, in separate groups of animals, intravertebral arterial (i.a.) administration of CP-99,994, SR 48212A or SR 48968. Dose-response relationships for i.v. and i.a. administration of each drug were generated to determine a ratio of i.v. ED50 to i.a. ED50, known as the effective dose ratio (EDR). The EDR will be 20 or greater for a centrally active drug and less than 20 for a peripherally active drug. 5. In the guinea-pig, CP-99,994 (0.1-30 mg kg-1, s.c.), SR 48212A (1.0-30 mg kg-1, s.c.), and SR 48968 (0.3-3.0 mg kg-1, s.c.) inhibited capsaicin-induced cough in a dose-dependent manner. Capsaicin-induced cough was also inhibited by i.c.v. administration of CP-99,994 (10 and 100 micrograms) or SR 48212A (100 micrograms). 6. In the cat, both CP-99,994 (0.0001-0.3 mg kg-1, i.a., n = 5; 0.003-3.0 mg kg-1, i.v., n = 5) and SR 48212A (0.003-1.0 mg kg-1, i.a., n = 5; 0.01-3.0 mg kg-1, i.v., n = 5) inhibited mechanically induced cough by either the i.v. or i.a. routes in a dose-dependent manner. SR 48968 (0.001-0.3 mg kg-1, i.a., n = 5; 0.03-1.0 mg kg-1, i.v., n = 5) inhibited cough when administered by the i.a. route in a dose-dependent manner, but had no effect by the i.v. route up to a dose of 1.0 mg kg-1. Intravenous antitussive potencies (ED50, 95% confidence interval (CI) of these compounds were: CP-99,994 (0.082 mg kg-1, 95% CI 0.047-0.126), SR 48212A (2.3 mg kg-1, 95% CI 0.5-20), and SR 48968 (> 1.0 mg kg-1, 95% CI not determined). The intra-arterial potencies of these compounds were: CP-99,994 (1.0 microgram kg-1, 95% CI 0.4-1.8), SR 48212A (25 micrograms kg-1, 95% CI 13-52), and SR 48968 (8.0 micrograms kg-1, 95% CI 1-32). The derived EDRs for each compound were: CP-99,994, 82; SR 48212A, 92; and SR 48968, > 125. 7. We concluded that CP-99,994 and SR 48968 inhibit cough in the guinea-pig and cat by a central site of action. In the cat, the antitussive action of these compounds appears to be solely by a central site.
Mathematical concepts of optical superresolution (2012)

Optical imaging beyond the diffraction limit, i.e., optical superresolution, has been studied extensively in various contexts. This paper presents an overview of some mathematical concepts relevant to superresolution in linear optical systems. Properties of bandlimited functions are surveyed and are related to both instrumental and computational aspects of superresolution. The phenomenon of superoscillation and its relation to superresolution are discussed.
Vibriobactin, a siderophore from Vibrio cholerae. (1984)

A novel siderophore (microbial iron transport compound) has been isolated from low iron cultures of Vibrio cholerae. Belonging to the catecholamide family of chelators, it has been shown to contain three residues of 2,3-dihydroxybenzoic acid and two residues of threonine. Both threonine moieties are present in the form of oxazoline rings. Furthermore, the polyamine backbone of the molecule was proved to be not spermidine, but the rare N-(3-aminopropyl)-1,3-diaminopropane, norspermidine. The structure of the new siderophore has been determined to be N-[3-(2,3-dihydroxybenzamido)propyl]-1, 3-bis[2,3-dihydroxyphenyl)-trans-5-methyl-2-oxazoline-4-carboxamido]prop ane. The compound has been given the trivial name vibriobactin. Mutants defective in the synthesis and utilization of vibriobactin were isolated. In an iron-limited environment V. cholerae was found to respond more strongly to vibriobactin, agrobactin, and ferrichrome than to enterobactin.
Altering the Substrate Specificity ofCandida rugosaLIP4 by Engineering the Substrate-Binding Sites (2007)

Candida rugosa (formerly Candida cylindracea) lipase (CRL) is an important industrial enzyme that is widely used in biotechnological applications such as the production of fatty acids and the synthesis of various esters. CRL comprises at least seven isozymes (LIP1-LIP7), which share a similar amino acid sequence but with different specificities for substrates. Previously, LIP4 was reported to have higher esterase activity toward long acyl-chain ester and lower lipase activity toward triglycerides. A296 and V344 of LIP4 were predicted to play decisive roles in its substrate specificity. In this study, site-specific saturation mutagenesis has been employed to study the substrate specificity of LIP4. Point mutations were separately introduced into A296 and V344 positions using degenerate primer sets containing 32 codons to generate two libraries of variants. LIP4 variants were heterologously expressed in the yeast Pichia pastoris. A specific plate assay was used to identify lipase-producing P. pastoris clones in a medium containing tributyrin. LIP4 variants with high activity toward short fatty acyl-chain triglyceride (tributyrin) were screened. Specificity analysis and biochemical characterization indicated that the recombinant variants A296I, V344Q, and V344H had properties remarkably different from those of wild-type LIP4. All three variant enzymes had significantly higher specific activities toward tributyrin than LIP4. In addition to short-chain triglyceride, A296I and V344Q also improved hydrolytic activities of triglycerides toward medium- and long-chain triglycerides tested. The results suggested that A296 played an important role in lipase activity and high-temperature dependence of LIP4, whereas it had no effect on the chain-length specificity in lipolytic reaction. The V344 residue had a significant effect on the substrate chain-length specificity of LIP4.
The effect of heat setting on the structure and mechanical properties of poly(ethylene terephthalate) fiber. I. Structural changes (1981)

Abstract We report structural changes in commercial multifilament poly(ethylene terephthalate) (PET) yarn when it is heat set in silicone oil over a range of temperatures between 100 and 220°C for times ranging from 1 min to 1 hr, while the yarn was (1) free to relax, and (2) held taut at constant length. In one case, viz., a sample heat treated for 1 hr, the cooling time was also varied to study the effect of rate of cooling. The free‐annealed and taut‐annealed samples showed considerable differences. The predominant role of the temperature of heat setting on structure is discussed in detail. There are considerable changes in the amount and orientation of the amorphous phase, and these will be shown to have important influence on mechanical properties in subsequent reports.
The identification and characterization of umbilical cord blood-derived human basophils (1998)

Cross-linking allergen-specific immunoglobin E on human peripheral blood basophils results in the release of histamine and other inflammatory mediators that initiate allergy and asthma. The signaling pathways leading from IgE binding to mediator release have not been well established, mainly due to the difficulty in obtaining adequate numbers of highly purified basophils. It was the goal of this study to easily obtain Fc epsilonRI-positive human basophils in high yield and purity for studies of signal transduction pathways. We describe an in vitro culture system in which pulsing normal human cord blood leukocytes with interleukin-3 (IL-3) for 3-4 h followed by incubation in medium with fetal bovine serum generates a cell population that is predominately Fc epsilonRI positive between 14 and 28 days of culture. These cells resemble peripheral blood basophils when examined by light and electron microscopy. Like normal blood basophils, they express the integrins, CD11b, CD18, CD29, and CD49d. A majority of the IL-3-pulsed cells also express a marker recognized by the basophil-specific antibody, 2D7. Fc epsilonRI cross-linking results in a time and dose-dependent release of histamine. Fc epsilonRI cross-linking also stimulates protein-tyrosine phosphorylation, thought to be the first event leading to the IgE-mediated activation of peripheral blood basophils. These studies establish cord blood as an accessible source from which basophil-like cells can be developed to examine Fc epsilonRI-mediated signal transduction.
Imaging of Lipids in Atheroma by Desorption Electrospray Ionization Mass Spectrometry (2009)

One of the hallmarks of atherosclerosis is the accumulation of lipoproteins within the wall of blood vessels. The lipid composition can vary among atheroma, even within a single individual, and is also dynamic, changing as the lesion progresses. One desirable characteristic of atheroma is their stability, as the rupture of unstable plaques can interfere with normal blood flow to the brain or heart, leading to stroke or heart attack. Desorption electrospray ionization mass spectrometry (DESI-MS) was used in this study for the profiling and imaging of arterial plaques. DESI-MS is an ambient ionization method in which a charged, nebulized solvent spray is directed a surface. In the positive and negative ion modes, sodium and chloride adducts, respectively, of diacyl glycerophosphocholines (GPChos), sphingomyelins (SMs), and hydrolyzed GPChos were detected. Also, cholesteryl esters were detected via adduct formation with ammonium cations. Finally, cholesterol was imaged in the atheroma by doping the charge labeling reagent betaine aldehyde directly into the DESI solvent spray, leading to in situ chemical derivatization of the otherwise nonionic cholesterol. DESI imaging experiments, in which the spatial distribution of the various chemical species is determined by scanning the DESI probe across an entire sample surface, revealed that there are lipid rich regions within the arterial walls, and the lipid rich regions seem to have one of two different lipid profiles. These lipid rich regions likely correspond to the areas of the tissue where lipoprotein particles have accumulated. It is also possible that the different lipid distributions may correlate with the stability or vulnerability of that particular region of the plaque.
Loss of CD26 protease activity in recipient mice during hematopoietic stem cell transplantation results in improved transplant efficiency (2012)

These results provide preclinical evidence of CD26, in the HSCT recipient, as a major regulator of HSC/HPC engraftment with minor effects on HSC/HPC homing and suggest the potential use of CD26 inhibitors in HSCT patients to improve transplant efficiency.
Simultaneous control of time-dependent population transfer dynamics and wave-packet quantum interferences inLi2by shaped ultrafast pulses (2002)

Ultrafast pulse shapes are used to control simultaneously the optimal population transfer coefficients and rotational wave-packet quantum interferences in the $E{}^{1}{\ensuremath{\Sigma}}_{g}^{+}$ state of ${\mathrm{Li}}_{2}$ $({\ensuremath{\nu}}_{E}=9,$ ${J}_{E}=27$ and 29). By dividing the spectral bandwidth of the ultrafast pulses into multiple ``control domains'' centered on each resonant wavelength, the population transfer coefficients can be manipulated independently of the wave-packet interferences to maximize the ${\mathrm{Li}}_{2}$ photoionization yield at arbitrary short pump-probe time delays. To investigate the population transfer coefficients with and without wave-packet interferences, respectively, the pump polarization is set to be either parallel to or at the magic angle (\ensuremath{\sim}55\ifmmode^\circ\else\textdegree\fi{}) relative to the probe polarization. A comparison is made between phases that are symmetric and antisymmetric about the resonances. The effects of resonant and nonresonant frequencies are separately established and quantified. It is estimated that up to 90% of the possible nonresonant Rabi oscillations can be brought into phase simultaneously for each rovibrational state in the wave packet, while at the same time a constant phase offset added to one of the control domains establishes the phase of the wave-packet interference.
Cardiovascular activity and chronic pain severity (2015)

This biobehavioral protocol enables measurement of chronic pain suffering and protection in three dimensions: physical, emotional, and cognitive.