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1.
Front Psychol ; 12: 619440, 2021.
Article En | MEDLINE | ID: mdl-33935870

It is well documented that training the rules employed in figural matrices tests enhances test performance. Previous studies only compare experimental conditions in which all or no rules were trained and therefore ignore the particular influence of knowledge about the easy and difficult rules. With the current study, we wanted to provide some first insights into this topic. Respondents were assigned to four groups that received training for no rules, only the easy rules, only the difficult rules, or for all rules. The results show that a training only for the difficult rules was more effective than the other trainings. This applies also to performance in the easy rules that were actually not part of the training. A possible explanation for this finding is a facilitation of the solution process that is primarily driven by knowledge about the difficult rules. In conclusion, our results demonstrate that taking differences between the rules into account may provide a deeper understanding of the effects of trainings for figural matrices tests.

2.
J Radiol Nurs ; 39(3): 168-173, 2020 Sep.
Article En | MEDLINE | ID: mdl-32837388

Since the initial reports surfaced of a novel coronavirus causing illness and loss of life in Wuhan, China, COVID-19 has rapidly spread across the globe, infecting millions and leaving hundreds and thousands dead. As hospitals cope with the influx of patients with COVID-19, new challenges have arisen as health-care systems care for patients with COVID-19 while still providing essential emergency care for patients with acute strokes and acute myocardial infarction. Adding to this complex scenario are new reports that patients with COVID-19 are at increased risk of thromboembolic complications including strokes. In this article, we detail our experience caring for acute stroke patients and provide some insight into neurointerventional workflow modifications that have helped us adapt to the COVID-19 era.

3.
J Neurophysiol ; 118(3): 1871-1887, 2017 09 01.
Article En | MEDLINE | ID: mdl-28679844

Birds and mammals use the interaural time difference (ITD) for azimuthal sound localization. While barn owls can use the ITD of the stimulus carrier frequency over nearly their entire hearing range, mammals have to utilize the ITD of the stimulus envelope to extend the upper frequency limit of ITD-based sound localization. ITD is computed and processed in a dedicated neural circuit that consists of two pathways. In the barn owl, ITD representation is more complex in the forebrain than in the midbrain pathway because of the combination of two inputs that represent different ITDs. We speculated that one of the two inputs includes an envelope contribution. To estimate the envelope contribution, we recorded ITD response functions for correlated and anticorrelated noise stimuli in the barn owl's auditory arcopallium. Our findings indicate that barn owls, like mammals, represent both carrier and envelope ITDs of overlapping frequency ranges, supporting the hypothesis that carrier and envelope ITD-based localization are complementary beyond a mere extension of the upper frequency limit.NEW & NOTEWORTHY The results presented in this study show for the first time that the barn owl is able to extract and represent the interaural time difference (ITD) information conveyed by the envelope of a broadband acoustic signal. Like mammals, the barn owl extracts the ITD of the envelope and the carrier of a signal from the same frequency range. These results are of general interest, since they reinforce a trend found in neural signal processing across different species.


Prosencephalon/physiology , Sound Localization , Animals , Auditory Pathways/physiology , Female , Male , Mesencephalon/physiology , Reaction Time , Strigiformes
4.
J Comput Neurosci ; 38(1): 143-66, 2015 Feb.
Article En | MEDLINE | ID: mdl-25278284

Characteristic delay and characteristic phase are shape parameters of interaural time difference tuning curves. The standard procedure for the estimation of these parameters is based on the measurement of delay curves measured for tonal stimuli with varying frequencies. Common to all procedures is the detection of a linear behavior of the phase spectrum. Hence a reliable estimate can only be expected if sufficiently many relevant frequencies are tested. Thus, the estimation precision depends on the given bandwidth. Based on a linear model, we develop and implement methods for the estimation of characteristic phase and delay from a single broadband tuning curve. We present two different estimation algorithms, one based on a Fourier-analytic interpretation of characteristic delay and phase, and the other based on mean square error minimization. Estimation precision and robustness of the algorithms are tested on artificially generated data with predetermined characteristic delay and phase values, and on sample data from electrophysiological measurements in birds and in mammals. Increasing the signal-to-noise ratio or the bandwidth increases the estimation accuracy of the algorithms. Frequency band location and strong rectification also affect the estimation accuracy. For realistic bandwidths and signal-to-noise ratios, the minimization algorithm reliably and robustly estimates characteristic delay and phase and is superior to the Fourier-analytic method. Bandwidth-dependent significance thresholds allow to assess whether the estimated characteristic delay and phase values are meaningful shape parameters of a measured tuning curve. These thresholds also indicate the sampling rates needed to obtain reliable estimates from interaural time difference tuning curves.


Auditory Pathways/physiology , Auditory Perception/physiology , Models, Neurological , Neurons/physiology , Psychoacoustics , Acoustic Stimulation , Action Potentials/physiology , Algorithms , Animals , Fourier Analysis , Humans , Time Factors
5.
Biochimie ; 92(9): 1164-72, 2010 Sep.
Article En | MEDLINE | ID: mdl-20447438

A series of 3-(N-alkyl-N-phenylamino)propan-2-ol derivatives were synthesized from epichlorohydrine in a multi-step strategy and were evaluated as Src kinase inhibitors. First, epoxy ring opening of epichlorohydrine was carried out in the presence of N-alkylanilines to yield 3-(N-alkyl-N-phenylamino)-1-chloro-propan-2-ol derivatives using Ca(OTf)2 as catalyst based on our previous studies [1]. Second, ring closure was performed under basic conditions to afford N-epoxymethyl N-alkylaniline derivatives. Finally, the epoxide ring opening with four different secondary amines and three nucleobases afforded the final products, i.e., a series of beta-amino alcohols. All compounds were screened for their inhibitory activity against Src kinase and anticancer activity on human breast carcinoma cells, BT-20 cell line. Among all compounds, 3-N-methyl-N-phenylamino-1-(pyrrolidin-1-yl)propan-2-ol (13b) exhibited the highest inhibitory potency (IC50=66.1 microM) against Src kinase. Structure-activity relationship studies suggested that the incorporation of bulky groups at position 1 and N-substitution with groups larger than methyl moiety, reduced the inhibitory potency of the compound significantly. Compounds 3-(N-ethyl-N-phenylamino-)-1-(4-methylpiperazin-1-yl)propan-2-ol (14c) and 3-(N-ethyl-N-phenylamino)-1-(thymine-1-yl)propan-2-ol (17) were found to inhibit the growth of breast carcinoma cells by approximately 45-49% at concentration of 50 microM.


Amino Alcohols/chemical synthesis , Amino Alcohols/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , src-Family Kinases/antagonists & inhibitors , Amino Alcohols/chemistry , Antineoplastic Agents/chemistry , Enzyme Inhibitors , Humans , Inhibitory Concentration 50 , Magnetic Resonance Spectroscopy , Molecular Structure , Structure-Activity Relationship , Tumor Cells, Cultured
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