Introduction: Neurologic complications remain one of the major risks after pediatric cardiac surgery. Cerebral autoregulation (CA) is a physiologic mechanism regulating cerebral perfusion. A dynamic intraoperative evaluation can possibly detect the impairment of the cerebral regulatory function during surgery.
View Article and Find Full Text PDFComplement receptor 1 (CR1) is a membrane glycoprotein with a highly duplicated domain structure able to bind multiple ligands such as C3b and C4b, the activated fragments of complement components C3 and C4, respectively. We have previously used our knowledge of this domain structure to identify CSL040, a soluble extracellular fragment of CR1 containing the long homologous repeat (LHR) domains A, B, and C. CSL040 retains the ability to bind both C3b and C4b but is also a more potent complement inhibitor than other recombinant CR1-based therapeutics.
View Article and Find Full Text PDFIn daily life, natural or man-made structures influence sound propagation, causing reflections and diffraction with potential effects on auditory spatial perception. While the effect of isolated reflections on binaural localization has been investigated, consequences of edge diffraction on spatial perception have received less attention. Here, effects of edge diffraction on the horizontal localization of a sound source were assessed when a flat square plate occludes the direct sound or produces a reflection in an otherwise anechoic environment.
View Article and Find Full Text PDFAdvancements in cochlear implants (CIs) have led to a significant increase in bilateral CI users, especially among children. Yet, most bilateral CI users do not fully achieve the intended binaural benefit due to potential limitations in signal processing and/or surgical implant positioning. One crucial auditory cue that normal hearing (NH) listeners can benefit from is the interaural time difference (ITD), .
View Article and Find Full Text PDFActive echolocation of sighted humans using predefined synthetic and self-emitted sounds, as habitually used by blind individuals, was investigated. Using virtual acoustics, distance estimation and directional localization of a wall in different rooms were assessed. A virtual source was attached to either the head or hand with realistic or increased source directivity.
View Article and Find Full Text PDFEvery-day acoustical environments are often complex, typically comprising one attended target sound in the presence of interfering sounds (e.g., disturbing conversations) and reverberation.
View Article and Find Full Text PDFJASA Express Lett
September 2022
Diffraction of sound occurs at sound barriers, building and room corners in urban and indoor environments. Here, a unified parametric filter representation of the singly diffracted field at arbitrary wedges is suggested, connecting existing asymptotic and exact solutions in the framework of geometrical acoustics. Depending on the underlying asymptotic (high-frequency) solution, a combination of up to four half-order lowpass filters represents the diffracted field.
View Article and Find Full Text PDFAwareness of space, and subsequent orientation and navigation in rooms, is dominated by the visual system. However, humans are able to extract auditory information about their surroundings from early reflections and reverberation in enclosed spaces. To better understand orientation and navigation based on acoustic cues only, three virtual corridor layouts (I-, U-, and Z-shaped) were presented using real-time virtual acoustics in a three-dimensional 86-channel loudspeaker array.
View Article and Find Full Text PDFRecent studies on loudness perception of binaural broadband signals in hearing impaired listeners found large individual differences, suggesting the use of such signals in hearing aid fitting. Likewise, clinical cochlear implant (CI) fitting with narrowband/single-electrode signals might cause suboptimal loudness perception in bilateral and bimodal CI listeners. Here spectral and binaural loudness summation in normal hearing (NH) listeners, bilateral CI (biCI) users, and unilateral CI (uCI) users with normal hearing in the unaided ear was investigated to assess the relevance of binaural/bilateral fitting in CI users.
View Article and Find Full Text PDFLead-DBS is an open-source, semi-automatized and widely applied software tool facilitating precise localization of deep brain stimulation electrodes both in native as well as in standardized stereotactic space. While automatized preprocessing steps within the toolbox have been tested and validated in previous studies, the interrater reliability in manual refinements of electrode localizations using the tool has not been objectified so far. Here, we investigate the variance introduced in this processing step by different raters when localizing electrodes based on postoperative CT or MRI.
View Article and Find Full Text PDFEffective biologics require high specificity and limited off-target binding, but these properties are not guaranteed by current affinity-selection-based discovery methods. Molecular counterselection against off targets is a technique for identifying nonspecific sequences but is experimentally costly and can fail to eliminate a large fraction of nonspecific sequences. Here, we introduce computational counterselection, a framework for removing nonspecific sequences from pools of candidate biologics using machine learning models.
View Article and Find Full Text PDFNext-generation sequencing (NGS) is an indispensable tool in antibody discovery projects. However, the limits on NGS read length make it difficult to reconstruct full antibody sequences from the sequencing runs, especially if the six CDRs are randomized. To overcome that, we took advantage of Illumina's cluster mapping capabilities to pair non-overlapping reads and reconstruct full Fab sequences with accurate V:V pairings.
View Article and Find Full Text PDFDifferences in interaural phase configuration between a target and a masker can lead to substantial binaural unmasking. This effect is decreased for masking noises with an interaural time difference (ITD). Adding a second noise with an opposing ITD in most cases further reduces binaural unmasking.
View Article and Find Full Text PDFThe successful discovery of novel biological therapeutics by selection requires highly diverse libraries of candidate sequences that contain a high proportion of desirable candidates. Here we propose the use of computationally designed factorizable libraries made of concatenated segment libraries as a method of creating large libraries that meet an objective function at low cost. We show that factorizable libraries can be designed efficiently by representing objective functions that describe sequence optimality as an inner product of feature vectors, which we use to design an optimization method we call stochastically annealed product spaces (SAPS).
View Article and Find Full Text PDFProc Natl Acad Sci U S A
April 2022
Late reverberation involves the superposition of many sound reflections, approaching the properties of a diffuse sound field. Since the spatially resolved perception of individual late reflections is impossible, simplifications can potentially be made for modelling late reverberation in room acoustics simulations with reduced spatial resolution. Such simplifications are desired for interactive, real-time virtual acoustic environments with applications in hearing research and for the evaluation of hearing supportive devices.
View Article and Find Full Text PDFObjective: This study investigated if individual preferences with respect to the trade-off between a good signal-to-noise ratio and a distortion-free speech target were stable across different masking conditions and if simple adjustment methods could be used to identify subjects as either "noise haters" or "distortions haters".
Design: In each masking condition, subjects could adjust the target speech level according to their preferences by employing (i) linear gain or gain at the cost of (ii) clipping distortions or (iii) compression distortions. The comparison of these processing conditions allowed investigating the preferred trade-off between distortions and noise disturbance.
The individual loudness perception of a patient plays an important role in hearing aid satisfaction and use in daily life. Hearing aid fitting and development might benefit from individualized loudness models (ILMs), enabling better adaptation of the processing to individual needs. The central question is whether additional parameters are required for ILMs beyond non-linear cochlear gain loss and linear attenuation common to existing loudness models for the hearing impaired (HI).
View Article and Find Full Text PDFIntroduction: Deep brain stimulation (DBS) is a highly efficacious treatment for essential tremor (ET). Still, the optimal anatomical target in the (sub)thalamic area is a matter of debate. The aim of this study was to determine the optimal target of DBS for ET regarding beneficial clinical outcome and impact on activities of daily living as well as stimulation-induced side effects and compare it with previously published coordinates.
View Article and Find Full Text PDFSound radiation of most natural sources, like human speakers or musical instruments, typically exhibits a spatial directivity pattern. This directivity contributes to the perception of sound sources in rooms, affecting the spatial energy distribution of early reflections and late diffuse reverberation. Thus, for convincing sound field reproduction and acoustics simulation, source directivity has to be considered.
View Article and Find Full Text PDFSmart headphones or hearables use different types of algorithms such as noise cancelation, feedback suppression, and sound pressure equalization to eliminate undesired sound sources or to achieve acoustical transparency. Such signal processing strategies might alter the spectral composition or interaural differences of the original sound, which might be perceived by listeners as monaural or binaural distortions and thus degrade audio quality. To evaluate the perceptual impact of these distortions, subjective quality ratings can be used, but these are time consuming and costly.
View Article and Find Full Text PDFThe sole inhibitory Fcγ receptor CD32b (FcγRIIb) is expressed throughout B and plasma cell development and on their malignant counterparts. CD32b expression on malignant B cells is known to provide a mechanism of resistance to rituximab that can be ameliorated with a CD32b-blocking antibody. CD32b, therefore, represents an attractive tumor antigen for targeting with a monoclonal antibody (mAb).
View Article and Find Full Text PDFPrion immunotherapy may hold great potential, but antibodies against certain PrP epitopes can be neurotoxic. Here, we identified > 6,000 PrP-binding antibodies in a synthetic human Fab phage display library, 49 of which we characterized in detail. Antibodies directed against the flexible tail of PrP conferred neuroprotection against infectious prions.
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