Martin Schmidt - Academia.edu (original) (raw)
Papers by Martin Schmidt
The Journal of Biological Chemistry, Nov 5, 2004
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Csi, 1999
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European Journal of Pharmacology, Jan 10, 2004
The membrane phospholipid, phosphatidylinositol 4,5-bisphosphate (PIP(2)), plays a critical role ... more The membrane phospholipid, phosphatidylinositol 4,5-bisphosphate (PIP(2)), plays a critical role in various, apparently very different cellular processes. As precursor for second messengers generated by phospholipase C isoforms and class I phosphoinositide 3-kinases, PIP(2) is indispensable for cellular signaling by membrane receptors. In addition, PIP(2) directly affects the localization and activity of many cellular proteins via specific interaction with unique phosphoinositide-binding domains and thereby regulates actin cytoskeletal dynamics, vesicle trafficking, ion channel activity, gene expression and cell survival. The activity and subcellular localization of phosphatidylinositol 4-phosphate 5-kinase (PIP5K) isoforms, which catalyze the formation of PIP(2), are actively regulated by membrane receptors, by phosphorylation and by small GTPases of the Rho and ARF families. Spatially and temporally organized regulation of PIP(2) synthesis by PIP5K enables dynamic and versatile PIP(2) signaling and represents an important link in the execution of cellular tasks by Rho and ARF GTPases.
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Ind Eng Chem Res, Aug 22, 2007
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2011 IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems (COMCAS 2011), 2011
An 15th order bandpass delta-sigma modulator for class-S power amplifiers is presented. The modul... more An 15th order bandpass delta-sigma modulator for class-S power amplifiers is presented. The modulator is based on a third order low pass prototype which is designed to meet the requirements for signal-to-noise ratio (SNR) of major mobile communication standards in a bandwidth of around 30 MHz. The transform z−1 → z−5 leads to a repetition of the low pass notch in the noise transfer function (NTF) at frequencies f = n/5fs, n = 1, 2, 3, 4, 5, &. Apart from sinc filtering due to rectangular output pulses the NTF shape is equal in all frequency bands. The two lower frequency bands at f = 1/5fs, 2/5 fs are independent from each other and can be used for concurrent transmission in the 450 MHz and 900 MHz band. The paper investigates the modulator with respect to the signal to noise ratio, the stability and the coding efficiency versus input amplitudes of tones in both frequency bands.
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Journal of the American Academy of Child and Adolescent Psychiatry, Jan 8, 2002
To measure specific neurophysiological attention deficits in children with hyperkinetic disorders... more To measure specific neurophysiological attention deficits in children with hyperkinetic disorders (HD; the ICD-10 diagnosis for severe and pervasive attention-deficit/hyperactivity disorder [ADHD]). In a multicenter sample of 148 children with HD and control children aged 8 to 14 years, event-related potential maps were recorded during a cued continuous performance test (A-X/O-X). Maps to cues (requiring attention but no response) and distractors and performance were tested for differences between age- and sex-matched HD and control groups (n = 57 each), as well as between clinics (n = 5). The N1, P3a, and P3b maps revealed reliable attention effects, with larger amplitudes after cues than after distractors, and only minor differences across clinics. Children with HD missed more targets, made more false alarms, and had larger N1 followed by smaller P3b amplitudes after cues than did controls. Cue-P3b amplitude correlated with detecting subsequent targets. Cue-P3b tomography indicated posterior sources that were attenuated in children with HD. Brain mapping indicates that children with HD attend to cues (preceding potential targets) with increased initial orienting (N1) followed by insufficient resource allocation (P3b). These multiple, condition-specific attention deficits in HD within 300 msec extend previous results on ADHD and underline the importance of high temporal resolution in mapping severe attention deficits.
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Kindh Entwickl, 2003
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Numerical Simulation of Optoelectronic Devices 2014, Sep 1, 2014
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Langmuir, Oct 1, 2004
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Journal of Biological Chemistry, May 9, 2002
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Makromolekulare Chemie Macromolecular Symposia, Oct 1, 1991
We have developed a highly sensitive, multi-angle, static light scattering (TRSLS = time resolved... more We have developed a highly sensitive, multi-angle, static light scattering (TRSLS = time resolved static light scattering) instrument, which measures the angular dependent Rayleigh scattering intensity of solutions simultaneously at 38 angles within approximately one second. It is thus suitable as a quick and easy to use static light scattering device for routine polymer and colloid characterization. The time resolution allows the kinetics of many systems to be investigated down to a second time scale, such as polymerization kinetics of linear, branched and crosslinked polymer structures, thermoreversible gelation, growth of colloidal particles, structural changes in micellar systems, etc.
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Molecular Pharmacology, Jun 1, 1998
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The Journal of Biological Chemistry, Nov 5, 2004
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Csi, 1999
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European Journal of Pharmacology, Jan 10, 2004
The membrane phospholipid, phosphatidylinositol 4,5-bisphosphate (PIP(2)), plays a critical role ... more The membrane phospholipid, phosphatidylinositol 4,5-bisphosphate (PIP(2)), plays a critical role in various, apparently very different cellular processes. As precursor for second messengers generated by phospholipase C isoforms and class I phosphoinositide 3-kinases, PIP(2) is indispensable for cellular signaling by membrane receptors. In addition, PIP(2) directly affects the localization and activity of many cellular proteins via specific interaction with unique phosphoinositide-binding domains and thereby regulates actin cytoskeletal dynamics, vesicle trafficking, ion channel activity, gene expression and cell survival. The activity and subcellular localization of phosphatidylinositol 4-phosphate 5-kinase (PIP5K) isoforms, which catalyze the formation of PIP(2), are actively regulated by membrane receptors, by phosphorylation and by small GTPases of the Rho and ARF families. Spatially and temporally organized regulation of PIP(2) synthesis by PIP5K enables dynamic and versatile PIP(2) signaling and represents an important link in the execution of cellular tasks by Rho and ARF GTPases.
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Ind Eng Chem Res, Aug 22, 2007
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2011 IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems (COMCAS 2011), 2011
An 15th order bandpass delta-sigma modulator for class-S power amplifiers is presented. The modul... more An 15th order bandpass delta-sigma modulator for class-S power amplifiers is presented. The modulator is based on a third order low pass prototype which is designed to meet the requirements for signal-to-noise ratio (SNR) of major mobile communication standards in a bandwidth of around 30 MHz. The transform z−1 → z−5 leads to a repetition of the low pass notch in the noise transfer function (NTF) at frequencies f = n/5fs, n = 1, 2, 3, 4, 5, &. Apart from sinc filtering due to rectangular output pulses the NTF shape is equal in all frequency bands. The two lower frequency bands at f = 1/5fs, 2/5 fs are independent from each other and can be used for concurrent transmission in the 450 MHz and 900 MHz band. The paper investigates the modulator with respect to the signal to noise ratio, the stability and the coding efficiency versus input amplitudes of tones in both frequency bands.
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Journal of the American Academy of Child and Adolescent Psychiatry, Jan 8, 2002
To measure specific neurophysiological attention deficits in children with hyperkinetic disorders... more To measure specific neurophysiological attention deficits in children with hyperkinetic disorders (HD; the ICD-10 diagnosis for severe and pervasive attention-deficit/hyperactivity disorder [ADHD]). In a multicenter sample of 148 children with HD and control children aged 8 to 14 years, event-related potential maps were recorded during a cued continuous performance test (A-X/O-X). Maps to cues (requiring attention but no response) and distractors and performance were tested for differences between age- and sex-matched HD and control groups (n = 57 each), as well as between clinics (n = 5). The N1, P3a, and P3b maps revealed reliable attention effects, with larger amplitudes after cues than after distractors, and only minor differences across clinics. Children with HD missed more targets, made more false alarms, and had larger N1 followed by smaller P3b amplitudes after cues than did controls. Cue-P3b amplitude correlated with detecting subsequent targets. Cue-P3b tomography indicated posterior sources that were attenuated in children with HD. Brain mapping indicates that children with HD attend to cues (preceding potential targets) with increased initial orienting (N1) followed by insufficient resource allocation (P3b). These multiple, condition-specific attention deficits in HD within 300 msec extend previous results on ADHD and underline the importance of high temporal resolution in mapping severe attention deficits.
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Kindh Entwickl, 2003
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Numerical Simulation of Optoelectronic Devices 2014, Sep 1, 2014
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Langmuir, Oct 1, 2004
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Journal of Biological Chemistry, May 9, 2002
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Makromolekulare Chemie Macromolecular Symposia, Oct 1, 1991
We have developed a highly sensitive, multi-angle, static light scattering (TRSLS = time resolved... more We have developed a highly sensitive, multi-angle, static light scattering (TRSLS = time resolved static light scattering) instrument, which measures the angular dependent Rayleigh scattering intensity of solutions simultaneously at 38 angles within approximately one second. It is thus suitable as a quick and easy to use static light scattering device for routine polymer and colloid characterization. The time resolution allows the kinetics of many systems to be investigated down to a second time scale, such as polymerization kinetics of linear, branched and crosslinked polymer structures, thermoreversible gelation, growth of colloidal particles, structural changes in micellar systems, etc.
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Molecular Pharmacology, Jun 1, 1998
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