gebhart/patrepeval huggingface dataset:
Toward MRI-guided coronary catheterization: Visualization of guiding catheters, guidewires, and anatomy in real time (2000)

The success of x-ray fluoroscopy-guided coronary catheterization depends in part on the ability to obtain simultaneous and real-time visualization of the guidewire, guiding catheter, and anatomy of the chest. The hypothesis explored in this paper is that magnetic resonance imaging (MRI) could provide this ability. This hypothesis was tested with loopless antennas used as the guidewire and a guiding catheter and two surface coils, each connected to four different receiver channels of a GE 1.5-T CV/I MRI scanner. Experiments were conducted on six healthy dogs. Intravascular antennas were inserted in the right carotid artery and maneuvered in the aorta while running a fast gradient-echo sequence (TR/TE 5/1.3 msec, flip angle 7 degrees). Real-time projection images of the chest anatomy, together with the guidewire and guiding catheter, were obtained. Positioning of the MRI guiding catheter either in the descending aorta, ascending aorta, or heart was achieved easily. This study represents a step toward MRI-guided coronary catheterization.
Permanent magnet assisted synchronous reluctance motor, design and performance improvement (2006)

Recently, permanent magnet assisted (PMa)-synchronous reluctance motors\n(SynRM) have been considered as a possible alternative motor drive for high\nperformance applications. In order to have an efficient motor drive, performing of three\nsteps in design of the overall drive is not avoidable. These steps are design optimization\nof the motor, identification of the motor parameter and implementation of an advanced\ncontrol system to ensure optimum operation.\nTherefore, this dissertation first deals with the design optimization of the Permanent\nMagnet Assisted Synchronous Reluctance Motor (PMa-SynRM). Various key points in\nthe rotor design of a low cost PMa-SynRM are introduced and their effects are studied.\nFinite element approach has been utilized to show the effects of these parameters on the\ndeveloped average electromagnetic torque and the total d-q inductances. As it can be\ninferred from the name of the motor, there are some permanent magnets mounted in the\nrotor core. One of the features considered in the design of this motor is the\nmagnetization of the permanent magnets mounted in the rotor core using the stator\nwindings to reduce the manufacturing cost. At the next step, identification of the motor parameters is discussed. Variation of\nmotor parameters due to temperature and airgap flux has been reported in the literatures.\nUse of off-line models for estimating the motor parameters is known as a\ncomputationally intensive method, especially when the models include the effect of\ncross saturation. Therefore in practical applications, on-line parameter estimation is\nfavored to achieve a high performance control system. In this dissertation, a simple\npractical method for parameter estimation of the PMa-SynRM is introduced.\nLast part of the dissertation presents one advanced control strategy which utilized the\nintroduced parameter estimator. A practical Maximum Torque Per Ampere (MTPA)\ncontrol scheme along with a simple parameter estimator for PMa-SynRM is introduced.\nThis method is capable of maintaining the MTPA condition and stays robust against the\nvariations of motor parameters.\nEffectiveness of the motor design procedure and the control strategy is validated by\npresenting simulation and experimental results of a 1.5 kW prototype PMa-SynRM,\ndesigned and manufactured through the introduced design method.
Dissociation constants, solubilities and dissolution rates of some selected nonsteroidal antiinflammatories (1983)

Dissociation constants, solubilities and dissolution rates have been investigated for 16 nonsteroidal antiinflammatory active compounds which belong to several chemical groups within the small class of acidic drug substances. The antiinflammatories are mostly characterized by a very low aqueous solubility at lower pH-values. The solubilities increase rapidly with pH's higher than the pKa. The pKa-values of the investigated compounds range from 3.5 to 6.3 with a mean directed to 4.6. The dissolution rate determinations of equimolar amounts at pH 7.5 show a great variation from half a minute to 60 minutes for the 50% level.
Functional polymers based on electron-donating TTF and derivatives (2007)

This review highlights the recent progress of electron-donating polymers containing thio-cyclic units (tetrathiafulvalene, dithiafulvene, thioketene dimers). These polymers with TTF derivatives in the main chain and side chain have been studied with the aim of improving processability of their charge transfer complexes and increasing the dimensionality of their conducting paths in the solid state. This review also highlights a novel synthetic methodology of the electroactive polymers, i.e., cycloaddition polymerization of bisthioketene to produce poly(dithiafulvene) and oxidative polymerization of bisdithiafulvenyl monomers and thioketene dimers. In the application of poly(dithiafulvene)s to the polymer–metal hybrid systems, they act as not only the reducing agent but also the stabilizer for the formed metal nanoparticles.
cDNA cloning of cholesterol 24-hydroxylase, a mediator of cholesterol homeostasis in the brain (1999)

The turnover of cholesterol in the brain is thought to occur via conversion of excess cholesterol into 24S-hydroxycholesterol, an oxysterol that is readily secreted from the central nervous system into the plasma. To gain molecular insight into this pathway of cholesterol metabolism, we used expression cloning to isolate cDNAs that encode murine and human cholesterol 24-hydroxylases. DNA sequence analysis indicates that both proteins are localized to the endoplasmic reticulum, share 95% identity, and represent a new cytochrome P450 subfamily (CYP46). When transfected into cultured cells, the cDNAs produce an enzymatic activity that converts cholesterol into 24S-hydroxycholesterol, and to a lesser extent, 25-hydroxycholesterol. The cholesterol 24-hydroxylase gene contains 15 exons and is located on human chromosome 14q32.1. Cholesterol 24-hydroxylase is expressed predominantly in the brain as judged by RNA and protein blotting. In situ mRNA hybridization and immunohistochemistry localize the expression of this P450 to neurons in multiple subregions of the brain. The concentrations of 24S-hydroxycholesterol in serum are low in newborn mice, reach a peak between postnatal days 12 and 15, and thereafter decline to baseline levels. In contrast, cholesterol 24-hydroxylase protein is first detected in the brain of mice at birth and continues to accumulate with age. We conclude that the cloned cDNAs encode cholesterol 24-hydroxylases that synthesize oxysterols in neurons of the brain and that secretion of 24S-hydroxycholesterol from this tissue in the mouse is developmentally regulated.
Molecular analysis of SNF2 and SNF5, genes required for expression of glucose-repressible genes in Saccharomyces cerevisiae. (1986)

The SNF2 and SNF5 genes are required for derepression of SUC2 and other glucose-repressible genes of Saccharomyces cerevisiae in response to glucose deprivation. Previous genetic evidence suggested that SNF2 and SNF5 have functionally related roles. We cloned both genes by complementation and showed that the cloned DNA was tightly linked to the corresponding chromosomal locus. Both genes in multiple copy complemented only the cognate snf mutation. The SNF2 gene encodes a 5.7-kilobase RNA, and the SNF5 gene encodes a 3-kilobase RNA. Both RNAs contained poly(A) and were present in low abundance. Neither was regulated by glucose repression, and the level of SNF2 RNA was not dependent on SNF5 function or vice versa. Disruption of either gene at its chromosomal locus still allowed low-level derepression of secreted invertase activity, suggesting that these genes are required for high-level expression but are not directly involved in regulation. Further evidence was the finding that snf2 and snf5 mutants failed to derepress acid phosphatase, which is not regulated by glucose repression. The SNF2 and SNF5 functions were required for derepression of SUC2 mRNA.
Electron Spin Relaxation Near a Micron-Size Ferromagnet (2001)

Magnetic resonance force microscopy was used to study the behavior of small ensembles of unpaired electron spins in silica near a micrometer-size ferromagnetic tip. Using a cantilever-driven spin manipulation protocol and a magnetic field gradient greater than 10(5) T/m, signals from as few as 100 net spins within a 20 nm thick resonant slice could be studied. A sixfold increase in the spin-lattice relaxation rate was found within 800 nm of the ferromagnet, while no effect due to silica surface proximity was detected. The results are interpreted in terms of Larmor-frequency magnetic field fluctuations emanating from the ferromagnet.
Beam engineering of quantum cascade lasers (2011)

Abstract This paper reviews beam engineering of mid‐infrared and terahertz quantum cascade lasers (QCLs), based on two approaches: designer plasmonic structures and deformed microcavities. The plasmonic structures couple laser emission into surface waves and control the laser wavefront in the near‐field, thereby greatly increasing beam collimation or introducing new functionalities to QCLs. The plasmonic designs overall preserve laser performance in terms of operating temperature and power output. The deformed microcavity QCLs operate primarily on whispering‐gallery modes, which have much higher quality factors than other modes, leading to lower threshold current densities. Cavity deformations are carefully controlled to greatly enhance directionality and output power.
Tides in confined well-aquifer systems (1971)

Tidal water-level fluctuations were recorded in ten observation wells in Virginia. Six wells are located on the Atlantic coastal plain, and four are in the Appalachian mountain region. A quantitative explanation of the observed well tides is developed from consideration of the tidal dilatation of an idealized well-aquifer system. The response of a confined well-aquifer system to tidal dilatations requires consideration of the earth tidal dilatation ΔE, the barometric tidal dilatation ΔB, and the ocean tide dilatation Δo according to the equation:

ΔA=-ρg dh(1-nEM+nEW)(1)

where ρ is fluid density, g is gravitational acceleration, dh is the height of the well tide, n is porosity, EM is the bulk modulus of the aquifer matrix, andEW is the fluid bulk modulus. The aquifer dilatation ΔA is given by the expression

ΔA=(ΔE+ΔBcosϕB+Δocosϕo)/cosϕA(2)

where ϕB, ϕo, and ϕA are phase differences between the tide-generating potential and the barometric tide, ocean tide, and well tide, respectively. For wells located far inland Δo can be neglected. For wells located near the ocean the explanation of tides requires analysis of at least two tidal harmonic constituents and the ratio of the heights of the corresponding ocean tide constituents. In this situation the above equation can be written simultaneously for two tidal harmonic constituents. The magnitudes of the ocean tide dilatations can be eliminated in solving the simultaneous equations, but their ratio must be known. Calculation of aquifer porosity from well tide analysis is restricted by uncertainty about bulk modulus and ocean loading effects. If a well-aquifer system is located far enough inland so that ocean tide effects can be neglected, porosity values can be obtained to an accuracy subjectively estimated at ±5 percentage points. Specific storage capacity of a well-aquifer system can be more accurately calculated than porosity because independent estimates of aquifer bulk modulus are not required.
Signaling and DNA-binding Activities of the Staphylococcus aureus HssR-HssS Two-component System Required for Heme Sensing (2007)

For the important human pathogen Staphylococcus aureus, host heme is a vital source of nutrient iron during infection. Paradoxically, heme is also toxic at high concentrations and is capable of killing S. aureus. To maintain cellular heme homeostasis, S. aureus employs the coordinated actions of the heme sensing two-component system (HssRS) and the heme regulated transporter efflux pump (HrtAB). HssRS-dependent expression of HrtAB results in the alleviation of heme toxicity and tempered staphylococcal virulence. Although genetic experiments have defined the role of HssRS in the heme-dependent activation of hrtAB, the mechanism of this activation is not known. Furthermore, the global effect of HssRS on S. aureus gene expression has not been evaluated. Herein, we combine multivariable difference gel electrophoresis with mass spectrometry to identify the heme-induced cytoplasmic HssRS regulon. These experiments establish hrtAB as the major target of activation by HssRS in S. aureus. In addition, we show that signaling between the sensor histidine kinase HssS and the response regulator HssR is necessary for growth of S. aureus in high concentrations of heme. Finally, we show that a direct repeat DNA sequence within the hrtAB promoter is required for heme-induced, HssR-dependent expression driven by this promoter and that phosphorylated HssR binds to this direct repeat upon exposure of S. aureus to high concentrations of heme. Taken together, these data establish the mechanism for HssRS-dependent expression of HrtAB and, in turn, provide a functional understanding for how S. aureus avoids heme-mediated toxicity.
Structure and function of cochlear afferent innervation (2010)

Purpose of review For the perception of sound, acoustic signals need to be encoded into a neuronal code. This takes place at the inner hair cells of the organ of Corti and the afferent fibres of the auditory nerve. We will review the current knowledge of the anatomy and function of these elements as well as their connection – formed by the afferent inner hair cell synapse. Recent findings Depending on their tonotopic location, inner hair cells are innervated by 5–30 dendrites of spiral ganglion neurons. Electrophysiological recordings from single fibres demonstrate – apart from a high-frequency selectivity – a pronounced heterogeneity in their response to sound of varying intensity. The source as well as the function of this heterogeneity is not well understood, but recent publications have suggested several mechanisms, including variations in the presynaptic Ca2+ influx and subsequent transmitter release, the postsynaptic sensitivity to neurotransmitter and electrical as well as anatomical variability of single fibres. These mechanisms might act together to expand the dynamic range of sound that can be encoded. Summary Classical studies as well as recent publications demonstrate that sound encoding at the inner hair cell afferent synapse involves mechanisms leading to tonotopic frequency separation and distribution of intensity coding over many neuronal channels.
Novel Binding Epitope for Helicobacter pylori Found in Neolacto Carbohydrate Chains (2005)

Helicobacter pylori is a bacterium that colonizes the stomach of a majority of the global human population causing common gastric diseases like ulcers and cancer. It has an unusually complex pattern of binding to various host glycoconjugates including interaction with sialylated, sulfated, and fucosylated sequences. The present study describes an additional binding epitope comprising the neolacto internal sequence of GlcNAcbeta3-Galbeta4GlcNAcbeta. The binding was detected on TLC plates as an interaction with a seven-sugar ganglioside of rabbit thymus. The glycolipid was purified and characterized as Neu5Gcalpha3Galbeta4GlcNAcbeta3Galbeta4GlcNAcbeta3-Galbeta4Glcbeta1Cer with less than 10% of the fraction carrying a repeated lacto (type-1) core chain, Galbeta3Glc-NAcbeta3Galbeta3GlcNAcbeta. After stepwise chemical and enzymatic degradation and structural analysis of products the strongest binder was found to be the pentaglycosylceramide GlcNAcbeta3Galbeta4GlcNAcbeta3Galbeta4Glcbeta1-Cer, whereas the hexa- and tetraglycosylceramides were less active, and the trihexosylceramide was inactive. Further studies revealed that the terminal GlcNAcbeta of the pentaglycosylceramide may be exchanged for either GalNAcbeta3, GalNAcalpha3, or Galalpha3 without loss of the activity. Calculated minimum energy conformers of these four isoreceptors show a substantial topographical similarity suggesting that this binding is a result of a molecular mimicry. Although the glycoconjugate composition of human gastric epithelial cells is not known in detail it is proposed that repeating N-acetyllactosamine units of glycoconjugates may serve as bacterial attachment sites in the stomach.
Iterative receivers for coded MIMO signaling (2004)

Abstract In this tutorial paper, we describe iterative receivers that combine a soft decoder for a general space‐time code with a spatial‐interference canceler. The performance of these receivers is analyzed by using EXIT charts, a convenient graphical description that yields quite accurate results. By properly combining the EXIT characteristics of the canceler and of the decoder, the convergence behavior of the iterative algorithms can be understood, and design guidelines derived. The idea here is to observe that both the interference canceler and the decoder can be studied by examining the evolution of the extrinsic information passed along to the connected blocks. Copyright © 2004 John Wiley & Sons, Ltd.
Psychoacoustic quantification of mechanical heart valve noise. (2005)

The results of this study showed that both sharpness and loudness have a significant influence on annoyance from closing sounds from mechanical heart valves, and indicated that the substantial variation in the parameters may be due to individual patient physiology.
Coating Processes (2011)

Abstract Coating process technology is in widespread use because the surface of most materials needs to be treated in order for the final product to meet all the functional needs and requirements. The modification is accomplished by applying a coating or series of coatings to the material to improve its performance and make it more suitable for use, or to give it different characteristics. Many of the commercially available coating applicators are described, including units for simultaneous multilayer application, for discrete coating, and for patch coating. While convection drying is emphasized, brief descriptions of conduction and infrared heating, as well as of UV and electron‐beam curing, are given.
High-strength pristine porous chitosan scaffolds for tissue engineering (2012)

Chitosan, a biodegradable naturally occurring polymer, has drawn considerable attention in recent years as a scaffolding material in tissue engineering and regenerative medicine. Despite its favorable biological properties, the weak mechanical strength of scaffolds produced from chitosan has limited the scope of their application. Here we fabricated 3D pristine porous chitosan scaffolds with unprecedented mechanical strength and investigated the regulatory role of chitosan and acidic concentrations on the crystallinity and thus on the mechanical and biological properties of produced scaffolds. Chitosan scaffolds of varying mechanical properties were prepared from solutions with chitosan concentrations of 4–12 wt%. The produced scaffolds showed no apparent shape change after immersion in Dulbecco's Modified Eagle Medium (DMEM), phosphate buffered saline, and simulated body fluid for two weeks. We showed that the crystallinity of the scaffold increased with increasing chitosan concentration or decreasing solution acidity, and the maximum compressive mechanical strength and modulus of 1.74 ± 0.01 MPa and 17.99 ± 0.11 MPa, respectively, were achieved at a chitosan concentration of 12 wt%. MG-63 osteoblast cells demonstrated improved adhesion, proliferation and osteogenic activity on chitosan scaffolds of increased chitosan concentration or mechanical strength. The ability to produce high-strength chitosan scaffolds and engineer their mechanical properties can substantially expand the applicability of chitosan in tissue engineering as well as other engineering applications.
Wavelength stabilization of a distributed Bragg reflector laser diode by use of complementary current injection (2003)

We have demonstrated wavelength stabilization in an 821-nm AlGaAs three-section tunable distributed Bragg reflector (DBR) semiconductor laser diode (LD) that consists of active, phase-controlled, and DBR regions. We injected two separate, complementary currents into the active and the phase-controlled regions in the DBR-LD to suppress wavelength shift. This modulation method was applied to the LD fundamental wave in a second-harmonic-generation (SHG) laser, and the oscillating wavelength was maintained within the phase-matching acceptance range of the SHG device during modulation. A peak blue-violet light power of 62 mW was obtained for the ideal modulation waveform.
Power-free Pump Module (PPM) and the Power-free Gas Sampler (PGS). (2020)

Abstract not provided.
Light‐dependent gene expression for proteins in the respiratory chain of potato leaves (2001)

Expression of genes for respiratory chain dehydrogenases was investigated in potato (Solanum tuberosum L. cv. Desiree) leaves. The recently characterized nda1 and ndb1 genes, homologues to genes encoding the non-proton pumping respiratory chain NADH-dehydrogenases of Escherichia coli and yeast, were compared to genes encoding catalytic subunits of the proton-pumping NADH dehydrogenase (complex I). As leaves develop from young to mature, the nda1 transcript level increases, accompanied by an elevation in immunodetected NDA protein and internal rotenone-insensitive NADH oxidation. The other investigated transcripts, proteins and NAD(P)H oxidation activities were essentially unchanged. A variation in transcript level, specific for nda1, is seen at different times of the day with highest expression in the morning. This variation also influences the apparent developmental induction. Further, the nda1 mRNA in leaves specifically and completely disappears during dark treatment, with a rapid re-induction when plants are returned to light. Corresponding immunodetected NDA protein is specifically decreased in mitochondria isolated from dark-treated plants, accompanied by a lower capacity for internal rotenone-insensitive NADH oxidation. Complete light dependence and diurnal changes in expression have previously not been reported for genes encoding respiratory chain proteins. Qualitatively similar to NDA, the alternative oxidase showed developmental induction and light dependence. In addition to the specific change in nda1, a general, slower down-regulation in darkness was seen for the other NAD(P)H dehydrogenase genes. The nda1 expression during development, and in response to light, indicates a specific role of the encoded enzyme in the photosynthetically associated mitochondrial metabolism.