bluuebunny/crossref_metadata_2025_split huggingface dataset:
Behandlung des therapieresistenten erosiven, oralen Lichen ruber mit extrakorporaler Photopherese (ECP)
Authors: Kunte Christian , Erlenkeuser‐Uebelhoer Istrid , Michelsen Silke , Scheerer‐Dhungel Karla , Plewig Gerd 
Published: October 2005

Zusammenfassung Hintergrund: Der erosive, orale Lichen ruber ist meist sehr therapieresistent. Histologisch und immunpathologisch sind Lichen ruber und lichenoide Graft‐versus‐host‐Erkrankung (GvHD) sehr ähnlich. Die Wirksamkeit der extrakorporalen Photopherese bei der GvHD wurde in einigen Arbeiten beschrieben, ebenso bei chronisch erosivem Lichen ruber in einer Publikation. Patienten und Methodik: Vier Patienten mit erosivem, oralen Lichen ruber wurden in die Studie eingeschlossen. Die Behandlung erfolgte an zwei aufeinanderfolgenden Tagen (1 Zyklus) in anfänglich zweiwöchigen Abständen. Die Therapieintervalle wurden bei klinischem Ansprechen verlängert. Ergebnisse: Eine Besserung der klinischen Symptomatik und Schleimhauterscheinungen war bei allen vier Patienten nach sieben bis neun Zyklen zu registrieren. Zahnärztliche Eingriffe führten bei zwei Patienten zu einer temporären Befundverschlechterung, bei einem dieser Patienten ist eine kontinuierliche Therapie erforderlich. Bei zwei Patienten wurde die Behandlung in fast abgeheiltem Zustand wegen des Auftretens unabhängiger Erkrankungen beendet. Bei einer Patientin Beendigung der Therapie nach 19 Zyklen bei kompletter Abheilung, Erscheinungsfreiheit auch neun Monate nach Therapieende. Nebenwirkungen traten nicht auf. Schlussfolgerung: Die extrakorporale Photopherese ist eine wirkungsvolle Therapie des oralen Lichen ruber, die vor allem wegen der fehlenden Nebenwirkungen eine gute Alternative zu den bislang gängigen Therapien darstellt. Die Behandlung sollte durch die Anwendungen von Lokaltherapeutika unterstützt werden.
Wave-number–frequency (k-ω) analysis using an eigenvalue decomposition technique
Authors: Salisbury John I. 
Published: October 2005

Noise source localization is of great interest and has been studied for many years. The information is used to detect and track objects in the ocean environment and to locate and identify position of radiating noise sources on objects for noise diagnostic efforts. In many cases the sonar system utilizes a line array having equally spaced sensors. Wave-number–frequency (k-ω) plots are used to analyze the data recorded by line arrays to detect the present of noise generators, either acoustically radiating targets located in the ocean environment or nonacoustical energy generated by the array itself. In this paper a hybrid technique (ED-FFT) is presented that uses an eigen decomposition (ED) technique in the spacial dimension and a fast Fourier transform (FFT) in the time domain. This combination generates k-ω plots having better spatial resolution than is currently possible using the conventional technique (FFT-FFT) has the added advantage of being able to separate the various noise generators and to eliminate any unwanted sources. In addition, it does not have the adverse effect of being signal-to-noise (SNR) dependent. Other techniques [autoregressive (AR) AR-AR, AR-FFT] have been investigated in order to improve the resolution of the k-ω plots [J. Acoust. Soc. Am. 87, 1603–1611 (1990); 90, 3155–3160 (1991)] and have been shown to be SNR dependent.
In this paper, the robust eigen decomposition technique has been utilized to generate high spatial resolution k-ω plots. The hybrid technique (ED-FFT) is implemented by taking a one-dimensional fast Fourier transform (FFT) on the sampled time series data and using these results to obtain a frequency-dependent cross spectral density matrix (CSD). Eigen decomposition is applied to this CSD matrix to obtain the eigenvalues and eigenvectors. An FFT is applied to the eigenvectors and modified according to the eigenvalues. The eigenvalues are arranged in descending order, the first being the largest and corresponds to the largest source. If only random noise is present, the eigenvalues will be equal and small. Each eigenvector represents an independent source, [IEEE J. Ocean Eng. OE-9(1) (1984)] therefore each source can be examined separately. This technique does not require any a priori knowledge of the number of sources as does techniques such as MUSIC [Trans. IEEE Antennas Propag. AP-34(3) (1986)] since it is not necessary to predetermine the signal and nonsignal subspace or the AR model order. Comparisons of the spacial resolution are made between the conventional method (FFT-FFT) and the hybrid (ED-FFT) for various target bearing angles using simulated data. The advantages of being able to isolate a particular noise generator is demonstrated.
Nonscattering of sound by sound resulting from a head-on collision of two plane-wave pulses
Authors: Westervelt Peter J. 
Published: October 2005

Two arbitrary pulses p2(t−c−10x) and p1(t+c−10x) each of width c0τ pass through one another at x=0, generating a differential surface mass rate source density dσs(t,x)=qs dx where qs=Ad(p1p2)/dt and A= (ρ0c40)−1[2 + ρ0c0−2(d2p/dρ2)ρ0]. The equation for the scattered pressure ps is d2ps/dx2−c−20 d2ps/dt2= −q̇s and its solution is ps(x’,t)=∫dps=(c0/2)∫dσs= (c0/2)∫qs(x,t’)dx, t’ being the retarded time; thus, (ps)± = (c0/2)A∫±c0τ/2x’[d(p1p2) t=t’±/dt]dx, where + is chosen when x’&lt;x, − when x’≳x, and t±’ = t ± c0−1(x’− x).
Suppose x’≳c0τ/2 then x’ lies outside the interaction zone, it is found that (ps)−= (c20A/4)(p2p1+ṗ2∫t−∞p1dt)=0 unless p1 has a nonzero average which is possible for plane waves but it is assumed that this is not the case [L. D. Landau and E. M. Lifshitz, FluidMechanics (Addison-Wesley, Reading, MA, 1959), p. 267]. In the event x’&lt;−c0τ/2x’ again lies outside the interaction zone and (ps)+= (c20A/4)(p1p2+ṗ1∫t−∞p2 dt)= 0. Within the interaction region −c20/2&lt;x’&lt;c0τ/2 so that ps=(ps)+ +(ps)−=(c20A/4)(2p1p2 +ṗ2∫t−∞p1 dt+ṗ1∫t−∞p2 dt), which is precisely the result obtained previously [P. J. Westervelt, J. Acoust. Soc. Am. 94, 1774 (A) (1993)], recalling that p1 is here a plane wave; thus in the earlier result pm=p1/2. The zero scattering results obtained here conflict with nonzero results obtained by Trivett and Rogers [J. Acoust. Soc. Am. 71, 1114 (1982)] in a related problem, which most likely stems from spurious sources arising from discontinuities similar to those that plagued Ingard and Pridmore-Brown.
Effects of carrier frequency, modulation rate, and modulation waveform on the detection of modulation and the discrimination of modulation type (amplitude modulation versus frequency modulation)
Authors: Moore Brian C. J. , Sek Aleksander 
Published: October 2005

Initially, psychometric functions were measured for the detection of amplitude modulation (AM) or frequency modulation (FM), using a two-alternative forced-choice (2AFC) task. Carrier frequencies were 125, 1000, and 6000 Hz, and modulation rates were 2, 5, and 10 Hz. For the two lower carrier frequencies, FM detection tended to be best at the lowest modulation rate while AM detection was best at the highest rate. For the 6000-Hz carrier, both AM and FM detection tended to be poorest at the lowest modulation rate. Then, pairs of values of AM and FM were selected that would be equally detectable, and psychometric functions were measured for the discrimination of AM from FM, again in a 2AFC task. For carrier frequencies of 125 and 1000 Hz, the ability to discriminate AM from FM was always poorest at the highest modulation rate (10 Hz); at this rate some subjects were essentially unable to discriminate AM from FM when the detectability of the modulation was relatively low (d′ of 1.16 and below). For a modulation rate of 2 Hz, and when the detectability of the modulation was moderate (d′ up to about 2), some subjects discriminated the type of modulation as well as they detected the modulation. For a carrier frequency of 6000 Hz, the effect of modulation rate varied across subjects, but there was still a trend for poorer discrimination of modulation type at the highest modulation rate.
It is suggested that FM detection at a 10-Hz modulation rate is based largely on changes in excitation level for all carrier frequencies. For a 2-Hz modulation rate, and for the two lowest carrier frequencies, an extra mechanism, possibly based on phase locking, may play a role in the detection and discrimination of FM. This mechanism may be ineffective at modulation rates above about 5 Hz because the stimuli spend insufficient time at frequency extremes. To check on this, psychometric functions were measured for the detection of FM and AM using quasitrapezoidal modulation with a rate of five periods per second and carriers of 250, 1000, and 6000 Hz. This produced improvements in performance relative to that obtained with 5-Hz sinusoidal modulation and, for the two lower carrier frequencies only, the improvements were markedly greater for FM than for AM detection. This is consistent with the idea that the use of phase-locking information depends on the time that the stimuli spend at frequency extremes.
Measurement and correction of ultrasonic pulse distortion produced by the human breast
Authors: Hinkelman Laura M. , Liu Dong-Lai , Waag Robert C. , Zhu Qing , Steinberg Bernard D. 
Published: October 2005

Ultrasonic wavefront distortion produced by transmission through breast tissue specimens was measured in a two-dimensional aperture. Differences in arrival time and energy level between the measured waveforms and references that account for geometric delay and spreading were calculated. Also calculated was a waveform similarity factor that is decreased from 1.0 by changes in waveform shape. For nine different breast specimens, the arrival time fluctuations had an average (±s.d.) rms value of 66.8 (±12.6) ns and an associated correlation length of 4.3 (±1.1) mm, while the energy level fluctuations had an average rms value of 5.0 (±0.5) dB and a correlation length of 3.4 (±0.8) mm. The corresponding waveform similarity factor was 0.910 (±0.023). The effect of the wavefront distortion on focusing and the ability of time-shift compensation to remove the distortion were evaluated by comparing parameters such as the −30-dB effective radius, the −10-dB peripheral energy ratio, and the level at which the effective radius departs from an ideal by 10% for the focus obtained without compensation, with time-shift estimation and compensation in the aperture, and with time-shift estimation and compensation performed after backpropagation. For the nine specimens, the average −10-dB peripheral energy ratio of the focused beams fell from 3.82 (±1.83) for the uncompensated data to 0.96 (±0.18) with time-shift compensation in the aperture and to 0.63 (±0.07) with time-shift compensation after backpropagation.
The average −30-dB effective radius and average 10% deviation level were 4.5 (±0.8) mm and −19.2 (±3.5) dB, respectively, for compensation in the aperture and 3.2 (±0.7) mm and −22.8 (±2.8) dB, respectively, for compensation after backpropagation. The corresponding radius for the uncompensated data was not meaningful because the dynamic range of the focus was generally less than 30 dB in the elevation direction, while the average 10% deviation level for the uncompensated data was −4.9 (±4.1) dB. The results indicate that wavefront distortion produced by breast significantly degrades ultrasonic focus in the low MHz frequency range and that much of this degradation can be eliminated using wavefront backpropagation and time-shift compensation.
A proposed microscopic elastic wave theory for ultrasonic backscatter from myocardial tissue
Authors: Rose James H. , Kaufmann Mark R. , Wickline Samuel A. , Hall Christopher S. , Miller James G. 
Published: October 2005

The physical structures responsible for ultrasonic scattering from myocardial tissue have not yet been conclusively defined. It is hypothesized in this paper that the backscatter from myocardium is primarily due to inhomogeneities approximately the size of the myocytes. In particular, it is proposed that the acoustic contrast responsible for the scattering is that between the extracellular collagen network that surrounds each myocyte (or myocyte bundle) and the rest of the tissue (the myocytes’ intracellular contents). To test this hypothesis, a simple elastic wave scattering model for myocardium was developed. An elementary scatterer is modeled as an ellipsoidal shell, having the material properties of wet collagen, imbedded in a host medium having the average properties of myocardium.
The first Born approximation to elastic scattering is used to calculate the frequency-dependent scattering from a single scatterer. To scale up from a single scatterer to a distribution of scatterers, it is assumed that the power received at the transducer is simply the sum of the power scattered in the direction of the transducer by each individual scatterer located in the active volume of the beam (an independent-scatterer approximation). Calculations are restricted to the backscattering direction (pulse-echo), although the theory can accommodate pitch–catch scattering at all angles. With the aid of a computer program, the acoustic backscatter coefficient is calculated using the Born formalism and then measurement effects (frequency-dependent beam width and attenuation correction factors) are incorporated to arrive at calculated integrated (frequency-averaged) backscatter. Both the backscatter coefficient and integrated backscatter are calculated for angles of incidence that range from parallel to the long axis of the scatterer to perpendicular to this fiber direction. For the low MHz frequencies typically used in clinical echocardiography, the calculated absolute magnitude of the acoustic backscatter coefficient lies within a range from 0.0001 to 0.001 cm−1 sr−1. For selected fiber geometries, the anisotropy in integrated backscatter as the angle of incidence is varied with respect to the fiber orientation is about 10 dB.
The predicted frequency dependence of the acoustic backscatter coefficient is calculated to be about f3.9 in the low MHz frequency range. These calculated results are reasonably consistent with published experimental measurements and provide a successful preliminary test of the hypothesis.
Phase effects in masking related to dispersion in the inner ear. II. Masking period patterns of short targets
Authors: Kohlrausch Armin , Sander Andres 
Published: October 2005

This article investigates how the amplitude and phase characteristics of the inner ear influence the spectrotemporal representation of harmonic complex sounds. Five experiments are reported, in each of which three sets of maskers are compared that differ only in their phase spectra. The amplitude spectra of the complexes were flat and the phase choices were (a) zero phase, (b) Schroeder phases with a positive sign, and (c) Schroeder phases with a negative sign. In the first four experiments, the spectra contained all harmonics between 200 and 2000 Hz. In experiments 1 and 2, the signal frequency was fixed at 1100 Hz and the fundamental frequency of the maskers was varied. In experiments 3 and 4, the fundamental frequency of the maskers was fixed and the signal frequency varied between 200 and 2000 Hz. In experiments 1 and 3, the signal duration was long compared to the period of the maskers. In experiments 2 and 4, the signal duration was only 5 ms and thresholds were determined for different time points within the masker’s period. The results show a strong correlation between the minima of the short signal’s thresholds and the threshold of the long signal. In experiment 5, the spectral extent of the masker was shifted to values one octave lower (100 to 1000 Hz) or one or two octaves higher (400 to 4000 Hz and 800 to 8000 Hz, respectively). For each spectral region, masked thresholds of a long signal were obtained for three values of the fundamental frequency.
In all five experiments the thresholds depended very much on the specific phase choices with differences of up to 25 dB. The masker with a negative Schroeder phase always led to the highest thresholds. The thresholds of the masker with a positive Schroeder phase, on the other hand, were for a wide range of parameters lower than the thresholds for the zero-phase masker. These phase effects are most likely caused by the phase characteristic of the basilar-membrane filter, which affects the flat envelopes of the two Schroeder-phase maskers in a very different way. For an appropriate choice of parameters, one of the two becomes even more strongly modulated than the zero-phase complex. This latter observation imposes some restrictions on the second derivative (curvature) of the phase-versus-frequency relation for the auditory filters.
Contribution of Trafficking Signals in the Cytoplasmic Tail of the Infectious Bronchitis Virus Spike Protein to Virus Infection
Authors: Youn Soonjeon , Collisson Ellen W. , Machamer Carolyn E. 
Published: October 2005

ABSTRACTCoronavirus spike (S) proteins are responsible for binding and fusion with target cells and thus play an essential role in virus infection. Recently, we identified a dilysine endoplasmic reticulum (ER) retrieval signal and a tyrosine-based endocytosis signal in the cytoplasmic tail of the S protein of infectious bronchitis virus (IBV). Here, an infectious cDNA clone of IBV was used to address the importance of the S protein trafficking signals to virus infection. We constructed infectious cDNA clones lacking the ER retrieval signal, the endocytosis signal, or both. The virus lacking the ER retrieval signal was viable. However, this virus had a growth defect at late times postinfection and produced larger plaques than IBV. Further analysis confirmed that the mutant S protein trafficked though the secretory pathway faster than wild-type S protein. A more dramatic phenotype was obtained when the endocytosis signal was mutated. Recombinant viruses lacking the endocytosis signal (in combination with a mutated dilysine signal or alone) could not be recovered, even though transient syncytia were formed in transfected cells. Our results suggest that the endocytosis signal of IBV S is essential for productive virus infection.
A Single-Cycle Vaccine Vector Based on Vesicular Stomatitis Virus Can Induce Immune Responses Comparable to Those Generated by a Replication-Competent Vector
Authors: Publicover Jean , Ramsburg Elizabeth , Rose John K. 
Published: October 2005

ABSTRACT
Live attenuated vaccine vectors based on recombinant vesicular stomatitis virus (VSV) are effective in several viral disease models. In this study, we asked if a VSV vector capable of only a single cycle of replication might be an effective alternative to replication-competent VSV vectors. We compared the cellular immune responses to human immunodeficiency virus (HIV) envelope protein (Env) expressed by replication-competent and single-cycle VSV vectors and also examined the antibody response to Env. The single-cycle vector was grown by complementation with VSV G protein and then tested initially for immunogenicity when given by four different routes. When given by the intramuscular route in mice, we found that the single-cycle vector was equivalent to the replication-competent VSV vector in generating high-level primary and memory CD8 T-cell responses as well as antibody responses to Env. Cellular responses were analyzed using major histocompatibility complex class I tetramers and direct measurement of cytotoxic T-lymphocyte activity in vivo. We also found that the recall responses after boosting were equivalent in animals vaccinated with replication-competent or single-cycle vectors. Additionally, we observed recall and heightened memory responses after boosting animals with a single-cycle vector complemented with G protein from a different vesiculovirus. Because expression of HIV Env by G-deleted VSV might allow replication in human cells expressing CD4, we generated a single-cycle VSV recombinant expressing a secreted form of the HIV Env protein. This virus was just as effective as the recombinant expressing the membrane-anchored Env protein at producing CD8 T cells and antibody responses.
Selective Escape from CD8
+
T-Cell Responses Represents a Major Driving Force of Human Immunodeficiency Virus Type 1 (HIV-1) Sequence Diversity and Reveals Constraints on HIV-1 Evolution
Authors: Allen Todd M. , Altfeld Marcus , Geer Shaun C. , Kalife Elizabeth T. , Moore Corey , O'Sullivan Kristin M. , DeSouza Ivna , Feeney Margaret E. , Eldridge Robert L. , Maier Erica L. , Kaufmann Daniel E. , Lahaie Matthew P. , Reyor Laura , Tanzi Giancarlo , Johnston Mary N. , Brander Christian , Draenert Rika , Rockstroh Jurgen K. , Jessen Heiko , Rosenberg Eric S. , Mallal Simon A. , Walker Bruce D. 
Published: October 2005

ABSTRACT

The sequence diversity of human immunodeficiency virus type 1 (HIV-1) represents a major obstacle to the development of an effective vaccine, yet the forces impacting the evolution of this pathogen remain unclear. To address this issue we assessed the relationship between genome-wide viral evolution and adaptive CD8
+
T-cell responses in four clade B virus-infected patients studied longitudinally for as long as 5 years after acute infection. Of the 98 amino acid mutations identified in nonenvelope antigens, 53% were associated with detectable CD8
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T-cell responses, indicative of positive selective immune pressures. An additional 18% of amino acid mutations represented substitutions toward common clade B consensus sequence residues, nine of which were strongly associated with HLA class I alleles not expressed by the subjects and thus indicative of reversions of transmitted CD8 escape mutations. Thus, nearly two-thirds of all mutations were attributable to CD8
+
T-cell selective pressures. A closer examination of CD8 escape mutations in additional persons with chronic disease indicated that not only did immune pressures frequently result in selection of identical amino acid substitutions in mutating epitopes, but mutating residues also correlated with highly polymorphic sites in both clade B and C viruses. These data indicate a dominant role for cellular immune selective pressures in driving both individual and global HIV-1 evolution. The stereotypic nature of acquired mutations provides support for biochemical constraints limiting HIV-1 evolution and for the impact of CD8 escape mutations on viral fitness.