Search results for "SPECTRA"

showing 10 items of 3542 documents

Verschiedenartige Additionsreaktionen von 2-Cyano-2-propylradikalen an p-Tolylmethacrylat und 4-Cyclohexylphenylmethacrylat

1976

Durch Umsetzung von p-Tolylmethacrylat oder 4-Cyclohexylphenylmethacrylat in stark verdunnter, siedender Benzollosung mit einem sehr grosen Uberschus an 2,2′-Azoisobutyronitril wurden die erwarteten Additionsprodukte mit 2-Cyano-2-propylradikalen (1) erhalten, namlich p-Tolyl- bzw. 4-Cyclohexylphenyl-[4-cyano-2-(2-cyano-2-propyl)-2,4-dimethyl]valerianat (3a bzw. 3b) mit rund 50% Ausbeute. Daneben wurden p-Tolyl- bzw. 4-Cyclohexylphenyl-(4-cyano-4-methyl-2-methylen)valerianat (4a bzw. 4b), p-Tolyl- bzw. 4-Cyclohexylphenyl-[4-cyano-2(2-cyano-2-methyl-1-propyl)-4-methyl]valerianat (5a bzw. 5b), p-Tolyl- bzw. 4-Cyclohexylphenyl-(4-cyano-2,4-dimethyl)valerianat (6a bzw. 6b) und p-Tolyl- bzw. 4-C…

Addition reactionUv spectraChemistryPolymer chemistryDisproportionationMass spectrometricDie Makromolekulare Chemie
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Noncontact monitoring of vascular lesion phototherapy efficiency by RGB multispectral imaging.

2013

A prototype low-cost RGB imaging system consisting of a commercial RGB CMOS sensor, RGB light-emitting diode ring light illuminator, and a set of polarizers was designed and tested for mapping the skin erythema index, in order to monitor skin recovery after phototherapy of vascular lesions, such as hemangiomas and telangiectasias. The contrast of erythema index (CEI) was proposed as a parameter for quantitative characterization of vascular lesions. Skin recovery was characterized as a decrease of the CEI value relative to the value before the treatment. This approach was clinically validated by examining 31 vascular lesions before and after phototherapy.

AdultDiagnostic ImagingSkin erythemaPathologymedicine.medical_specialtyErythemaMultispectral imageBiomedical EngineeringBiomaterialsYoung AdultMedicineHumansTelangiectasisSkinCMOS sensorintegumentary systembusiness.industrySpectrum AnalysisVascular lesionMiddle AgedPhototherapyAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsTreatment OutcomeErythemaRGB color modelmedicine.symptombusinessHemangiomaBiomedical engineeringJournal of biomedical optics
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Metabolite identification in human liver needle biopsies by high-resolution magic angle spinning1H NMR spectroscopy

2006

High-resolution magic angle spinning (HR-MAS) 1 H NMR spectroscopy of intact human liver needle biopsies has not been previously reported. HR-MAS NMR spectra collected on 17 specimens with tissue amounts between � 0.5 and 12 mg showed very good spectral resolution and signal-to-noise ratios. One-dimensional 1 H spectra revealed many intense signals corresponding to cellular metabolites. In addition, some high molecular weight metabolites, such as glycogen and mobile fatty acids, could be observed in some spectra. Resonance assignments for 22 metabolites were obtained by combining the analysis of three different types of 1D 1 H spectral editing, such as T2 filtering or the nuclear Overhauser…

AdultLiver CirrhosisMaleMagnetic Resonance SpectroscopyMetaboliteNuclear Overhauser effectSensitivity and Specificitychemistry.chemical_compoundNuclear magnetic resonanceMagic angle spinningHumansRadiology Nuclear Medicine and imagingSpectroscopySpectroscopyAgedHepatitis ChronicChemistryBiopsy NeedleReproducibility of ResultsResonanceNuclear magnetic resonance spectroscopyMiddle AgedNMR spectra databaseProton NMRMolecular MedicineFemaleSpin Labelslipids (amino acids peptides and proteins)ProtonsBiomarkersNMR in Biomedicine
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Curvature of iris profile in spectral domain optical coherence tomography and dependency to refraction, age and pupil size - the MIPH Eye&Health …

2016

Purpose Optical coherence tomography (OCT) of the anterior segment allows quantitative analysis of the geometry of the iris. We performed spectral domain OCT examinations in healthy emmetropic, hyperopic and myopic subjects to investigate iris curvature and its associations. Methods In a cross-sectional study, out of 4617 eyes (2309 subjects) those with refractive errors of +3 dioptres were identified by objective refraction. The iris was examined using the anterior segment mode of a spectral domain 3D OCT-2000 (Topcon Inc., Japan) in the temporal meridian, and OCT scans were investigated with respect to presence and amount of convex and concave iris configuration. Ninety-three eyes of 50 s…

AdultMaleAdolescentgenetic structuresGonioscopyIrisEmmetropiaSpectral domainRefraction OcularCurvatureYoung Adult03 medical and health sciences0302 clinical medicineOptical coherence tomographyAnterior Eye SegmentGermanyEye healthHumansMedicineIntraocular PressureAgedmedicine.diagnostic_testbusiness.industryIncidenceAge FactorsPupil sizePupilGeneral MedicineMiddle AgedRefractive ErrorsRefractioneye diseasesOphthalmologyCross-Sectional StudiesMeridian (perimetry visual field)030221 ophthalmology & optometryOptometryFemalesense organsbusinessTomography Optical Coherence030217 neurology & neurosurgeryActa Ophthalmologica
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Synchronization to metrical levels in music depends on low-frequency spectral components and tempo

2016

Previous studies have found relationships between music-induced movement and musical characteristics on more general levels, such as tempo or pulse clarity. This study focused on synchronization abilities to music of finely-varying tempi and varying degrees of low frequency spectral change/flux. Excerpts from six classic Motown/R&B songs at three different tempos (105, 115, and 130 BPM) were used as stimuli in this experiment. Each was then time-stretched by a factor of 5% with regards to the original tempo, yielding a total of 12 stimuli that were presented to 30 participants. Participants were asked to move along with the stimuli while being recorded with an optical motion capture system.…

AdultMaleAuditory perceptionSpectral fluxBar (music)Speech recognitionmusiikkiExperimental and Cognitive PsychologyMotor Activity050105 experimental psychologySynchronizationliikkeetYoung Adult03 medical and health sciences0302 clinical medicineArts and Humanities (miscellaneous)low-frequency spectral componentsDevelopmental and Educational PsychologyHumans0501 psychology and cognitive sciencesCommunicationMovement (music)business.industry05 social sciencesGeneral Medicinemetrical levels in musicTime perceptionPulse (music)temporytmioppiTime PerceptionAuditory PerceptionFemalesynkronointiPsychologybusinesssynchronizationBeat (music)Music030217 neurology & neurosurgeryPsychological Research
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Individual and common antigen-recognition sites of liver-derived T cells in patients with autoimmune hepatitis.

2003

Autoimmune hepatitis (AIH) is characterized by dense T-cell infiltrations in the liver tissue, but little is known how T cells influence the pathogenesis. To address this question, the distribution of T-cell receptor variable beta-chain (TCR Vbeta) transcripts of peripheral blood and liver-infiltrating T cells from previously untreated patients with newly diagnosed acute exacerbated AIH was investigated. Furthermore, the lengths and sequences of complementary-determining region 3 (CDR3) were studied. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis and CDR3 spectratyping revealed multiple clonal expansions of liver-infiltrating T cells but not peripheral T cells within vari…

AdultMaleBiopsyT-LymphocytesImmunologyMolecular Sequence DataReceptors Antigen T-CellEpitopes T-Lymphocytechemical and pharmacologic phenomenaInflammationAutoimmune hepatitisBiologyCDR3 SpectratypingEpitopePathogenesismedicineHumansAmino Acid SequenceRNA MessengerReceptorAgedBase SequenceReverse Transcriptase Polymerase Chain ReactionT-cell receptorhemic and immune systemsGeneral MedicineMiddle Agedmedicine.diseaseComplementarity Determining RegionsClone CellsHepatitis AutoimmuneGene Expression RegulationImmunologyFemalemedicine.symptomNested polymerase chain reactionScandinavian journal of immunology
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Human cerebral microcirculation and oxygen saturation during propofol-induced reduction of bispectral index †

2011

† This study investigates the effects of propofol-induced changes in bispectral index (BIS) on cerebral microcirculation and oxygenation during craniotomies. † In 2 mm cerebral depth, an increase in propofol dosage resulted in increased oxygen saturation (srvO2 )w ithout reduction of capillary venous blood flow (rvCBF). † Difference in oxygen content (avDO2) and approximated cerebralmetabolicrateofoxygen (aCMRO2) decreased with an increase in propofol dosage in 2 mm cerebral depth. † Alterations in BIS showed no effect on rvCBF, srvO2 ,a nd haemoglobin amount (rvHb) or on avDO2 or aCMRO2 in 8 mm cerebral depth. † These findings suggest that the CBF/CMRO2 ratio is altered by propofol in a re…

AdultMaleCerebral oxygen saturationMicrocirculationRemifentanilHemoglobinsConsciousness MonitorsPiperidinesMonitoring IntraoperativeLaser-Doppler FlowmetrymedicineHumansOximetryPropofolOxygen saturation (medicine)Dose-Response Relationship Drugbusiness.industryMicrocirculationSpectrum AnalysisBrainOxygenationMiddle AgedOxygenOxygen Saturation MeasurementAnesthesiology and Pain MedicineCerebral blood flowCerebrovascular CirculationAnesthesiaBispectral indexFemalePropofolbusinessAnesthetics IntravenousCraniotomymedicine.drugBritish Journal of Anaesthesia
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Neural net classification of REM sleep based on spectral measures as compared to nonlinear measures

2001

In various studies the implementation of nonlinear and nonconventional measures has significantly improved EEG (electroencephalogram) analyses as compared to using conventional parameters alone. A neural network algorithm well approved in our laboratory for the automatic recognition of rapid eye movement (REM) sleep was investigated in this regard. Originally based on a broad range of spectral power inputs, we additionally supplied the nonlinear measures of the largest Lyapunov exponent and correlation dimension as well as the nonconventional stochastic measures of spectral entropy and entropy of amplitudes. No improvement in the detection of REM sleep could be achieved by the inclusion of …

AdultMaleCorrelation dimensionGeneral Computer ScienceEntropySleep REMLyapunov exponentElectroencephalographysymbols.namesakeStatisticsmedicineHumansEntropy (information theory)MathematicsQuantitative Biology::Neurons and Cognitionmedicine.diagnostic_testArtificial neural networkbusiness.industrySpectral entropyEye movementElectroencephalographyPattern recognitionNonlinear systemNonlinear DynamicssymbolsNeural Networks ComputerArtificial intelligencebusinessAlgorithmsBiotechnologyBiological Cybernetics
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Alterations of Continuous MEG Measures during Mental Activities

2000

In a pilot study, we investigated the topography of 11 continuous MEG measures for the eyes-opened and eyes-closed condition together with three simple mental tasks (mental arithmetic, visual imagery, word generation). One-minute recordings for each condition from 16 right-handed subjects were analyzed. The electrophysiological measures consisted of 6 spectral band measures together with spectral edge frequency and spectral entropy, plus the time-domain-based entropy of amplitudes (ENA) and the nonlinear measures correlation dimension D2 and Lyapunov exponent L1. In summary, our results indicate a pronounced task-dependent difference between the anterior and the posterior region, but no lat…

AdultMaleCorrelation dimensionmedicine.medical_specialtyEntropyFixation OcularLyapunov exponentAudiologyLateralization of brain functionDevelopmental psychologysymbols.namesakeCognitionMental ProcessesmedicineHumansEntropy (information theory)Biological PsychiatryBrainMagnetoencephalographySpectral bandsPsychiatry and Mental healthNeuropsychology and Physiological PsychologyAmplitudeNonlinear DynamicssymbolsFemaleSleep StagesSpectral edge frequencyPsychologyAlgorithmsMental imageNeuropsychobiology
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The effects of post-awakening light exposure on the cortisol awakening response in healthy male individuals.

2019

Abstract Background It is assumed that the expression of the cortisol awakening response (CAR) is modulated by light exposure during the peri-awakening period. While initial evidence supports this principal effect, the specific role of the spectral composition of light (brightness and wavelength) is still incompletely understood. Method Two counterbalanced within-subject experiments were conducted in a standardized sleep laboratory setting to investigate the effect of light intensity (study I; two days: dim vs. bright light) and spectral composition (study II; three days: red vs. blue vs. green light) on the CAR. Across studies, light exposure was conducted for one-hour post-awakening and t…

AdultMaleCortisol awakening responseHydrocortisoneLightEndocrinology Diabetes and MetabolismPhysiology03 medical and health sciencesYoung Adult0302 clinical medicineEndocrinologyMedicineHumansWakefulnessSalivaBiological PsychiatrySpectral compositionLight exposureEndocrine and Autonomic Systemsbusiness.industrySleep laboratoryPhototherapyHealthy Volunteers030227 psychiatryCircadian RhythmPsychiatry and Mental healthLight intensitybusinessSleep030217 neurology & neurosurgeryBright lightPsychoneuroendocrinology
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