338 results on '"Wieser J"'
Search Results
152. Layout and analysis: Finding text, titles, and photos in digital images of newspaper pages
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Wieser, J., primary and Pinz, A., additional
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153. Will Moore's Law rule in the land of analog?
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Rutenbar, Rob A., Bonaccio, T., Meng, T., Perea, E., Pitts, R., Sodinii, C., and Wieser, J.
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- 2004
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154. Will Moore's Law rule in the land of analog?
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Rutenbar, R.A., Bonaccio, T., Meng, T., Perea, E., Pitts, R., Sodini, C., and Wieser, J.
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- 2004
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155. Optical diagnostics of plasmas created by relativistic heavy ion beam interaction with solid targets.
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Dewald, E., Jacoby, J., Roth, M., Bock, R., Constantin, C., Niemann, C., Udrea, S., Varentsov, D., Wieser, J., Kozyreva, A., Tauschwitz, A., Hoffmann, D.H., Neuner, U., Shutov, A., and Tahir, N.
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- 2001
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156. Rapid recording of the characteristic parameters of the ferromagnetic hysteresis loop.
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Martin, W. E. and Wieser, J.
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- 1982
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157. Heavy ion beam pumped amplified spontaneous emission on the 172 nm xenon excimer transition.
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Busch, B., Ulrich, A., Krötz, W., Ribitzki, G., Wieser, J., and Winkler, M.
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NOBLE gases , *ION bombardment - Abstract
Presents a study which demonstrated a method of pumping rare gas excimers using high instantaneous power densities obtained by using pulsed heavy ion beams. Background on spectroscopic studies of rare gases excited by heavy ion beams; Materials and methods used; Approaches in determining optical gain.
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- 1993
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158. Excimer Laser Pumped by an Intense, High-Energy Heavy-Ion Beam
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Wieser, J [Coherent GmbH, Munich site, Zielstattstrasse 32, D-81379 Munich (Germany)]
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- 2006
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159. Ion-beam excitation of liquid argon.
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Hofmann, M., Dandl, T., Heindl, T., Neumeier, A., Oberauer, L., Potzel, W., Roth, S., Schönert, S., Wieser, J., and Ulrich, A.
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ION beams , *NUCLEAR excitation , *LIQUID argon , *SCINTILLATION spectrometry , *WAVELENGTHS , *TIME-resolved spectroscopy - Abstract
The scintillation light of liquid argon has been recorded wavelength and time resolved with very good statistics in a wavelength interval ranging from 118 nm through 970 nm. Three different ion beams, protons, sulfur ions and gold ions, were used to excite liquid argon. Only minor differences were observed in the wavelength-spectra obtained with the different incident particles. Light emission in the wavelength range of the third excimer continuum was found to be strongly suppressed in the liquid phase. In time-resolved measurements, the time structure of the scintillation light can be directly attributed to wavelength in our studies, as no wavelength shifter has been used. These measurements confirm that the singlet-to-triplet intensity ratio in the second excimer continuum range is a useful parameter for particle discrimination, which can also be employed in wavelength-integrated measurements as long as the sensitivity of the detector system does not rise steeply for wavelengths longer than 190 nm. Using our values for the singlet-to-triplet ratio down to low energies deposited a discrimination threshold between incident protons and sulfur ions as low as ∼2.5 keV seems possible, which represents the principle limit for the discrimination of these two species in liquid argon. [ABSTRACT FROM AUTHOR]
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- 2013
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160. Attenuation of vacuum ultraviolet light in liquid argon.
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Neumeier, A., Hofmann, M., Oberauer, L., Potzel, W., Schönert, S., Dandl, T., Heindl, T., Ulrich, A., and Wieser, J.
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ULTRAVIOLET radiation , *LIQUID argon , *ATTENUATION (Physics) , *VACUUM , *WAVELENGTHS - Abstract
The transmission of liquid argon has been measured, wavelength resolved, for a wavelength interval from 118 to 250 nm. The wavelength dependent attenuation length is presented for pure argon. It is shown that no universal wavelength independent attenuation length can be assigned to liquid argon for its own fluorescence light due to the interplay between the wavelength dependent emission and absorption. A decreasing transmission is observed below 130 nm in both chemically cleaned and distilled liquid argon and assigned to absorption by the analogue of the first argon excimer continuum. For not perfectly cleaned argon a strong influence of impurities on the transmission is observed. Two strong absorption bands at 126.5 and 141.0 nm with approximately 2 and 4 nm width, respectively, are assigned to traces of xenon in argon. A broad absorption region below 180 nm is found for unpurified argon and tentatively attributed to the presence of water in the argon sample. [ABSTRACT FROM AUTHOR]
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- 2012
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161. Formation of O/W emulsions by static mixers for pharmaceutical applications
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Kiss, N., Brenn, G., Pucher, H., Wieser, J., Scheler, S., Jennewein, H., Suzzi, D., and Khinast, J.
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LAMINAR flow , *MICROSPHERES , *SCALING laws (Statistical physics) , *MULTIPHASE flow , *MATHEMATICAL models , *FATS & oils , *WATER - Abstract
Abstract: Oil-in-water (O/W) emulsions produced by static mixers in the laminar flow regime are characterized for their oil drop size spectra. The emulsions are used in the first process step for the production of microspheres for pharmaceutical applications by the emulsion extraction method. However, emulsion generation by static mixers in the laminar flow regime is rarely discussed in the scientific literature. Here we deduce a non-dimensional correlation for predicting the Sauter mean oil drop size as a function of the static mixer operation parameters and the liquid properties. First, the material properties of the organic and water phases are characterized. Second, the oil drop size spectra of the emulsions are measured by laser diffraction. Dimensional analysis is used to describe the relationship between the process parameters of the static mixer and the Sauter mean oil droplet size. Emulsion production experiments using SMX static mixers with two different diameters are carried out with the mixing of the two liquids taking place in the laminar flow regime. We provide results covering a wide range of all process parameters, which were identified influencing the droplet size of the emulsion. The correlation achieved is related to the non-dimensional drop-size based Ohnesorge number of the emulsification process and allows for the prediction of the mean oil droplet size with good accuracy, which is an essential information about the emulsion properties relevant for the pharmaceutical application. [Copyright &y& Elsevier]
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- 2011
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162. Transmission of ∼10 keV electron beams through thin ceramic foils: Measurements and Monte Carlo simulations of electron energy distribution functions.
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Morozov, A., Heindl, T., Skrobol, C., Wieser, J., Krücken, R., and Ulrich, A.
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ELECTRON beams , *ELECTRON optics , *MONTE Carlo method , *PARTICLES (Nuclear physics) , *NUCLEAR physics , *SIMULATION methods & models - Abstract
Electron beams with particle energy of ~10 keV were sent through 300 nm thick ceramic (Si3N4 + SiO2) foils and the resulting electron energy distribution functions were recorded using a retarding grid technique. The results are compared with Monte Carlo simulations performed with two publicly available packages, Geant4 and Casino v2.42. It is demonstrated that Geant4, unlike Casino, provides electron energy distribution functions very similar to the experimental distributions. Both simulation packages provide a quite precise average energy of transmitted electrons: we demonstrate that the maximum uncertainty of the calculated values of the average energy is 6% for Geant4 and 8% for Casino, taking into account all systematic uncertainties and the discrepancies in the experimental and simulated data. [ABSTRACT FROM AUTHOR]
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- 2008
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163. Fundamental Studies of Intense Heavy-Ion Beam Interaction With Solid Targets.
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Dewald, Eduard, Constantin, Carmen, Niemann, Christoph, Udrea, S., Jacoby, J., Wieser, J., Varentsov, D., Tahir, N.A., Kozyreva, A., Shutov, A., Schlegel, T., Tauschwitz, Andreas, Hoffmann, Dieter H.H., and Bock, R.
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ION bombardment , *ELECTROMAGNETIC interactions , *SOLIDS - Abstract
Presents a study that examined intense heavy-ion beam interaction with solid targets. Experimental setup; Results and discussion; Conclusion.
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- 2003
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164. Determination of Hydrogen Density by Swift Heavy Ions.
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Ge Xu, Barriga-Carrasco, M. D., Blazevic, A., Borovkov, B., Casas, D., Cistakov, K., Gavrilin, R., Iberler, M., Jacoby, J., Loisch, G., Morales, R., Mäder, R., Qin, S.-X., Rienecker, T., Rosmej, O., Savin, S., Schönlein, A., Weyrich, K., Wiechula, J., and Wieser, J.
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ELECTRON density , *HEAVY ions , *HYDROGEN - Abstract
A novel method to determine the total hydrogen density and, accordingly, a precise plasma temperature in a lowly ionized hydrogen plasma is described. The key to the method is to analyze the energy loss of swift heavy ions interacting with the respective bound and free electrons of the plasma. A slowly developing and lowly ionized hydrogen theta-pinch plasma is prepared. A Boltzmann plot of the hydrogen Balmer series and the Stark broadening of the Hß line preliminarily defines the plasma with a free electron density of (1.9±0.1)×1016 cm-3 and a free electron temperature of 0.8-1.3 eV. The temperature uncertainty results in a wide hydrogen density, ranging from 2.3×1016 to 7.8×1018 cm-3. A 108 MHz pulsed beam of 48Ca10+ with a velocity of 3.652 MeV/u is used as a probe to measure the total energy loss of the beam ions. Subtracting the calculated energy loss due to free electrons, the energy loss due to bound electrons is obtained, which linearly depends on the bound electron density. The total hydrogen density is thus determined as (1.9±0.7)×1017 cm-3, and the free electron temperature can be precisely derived as 1.01±0.04 eV. This method should prove useful in many studies, e.g., inertial confinement fusion or warm dense matter. [ABSTRACT FROM AUTHOR]
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- 2017
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165. AVERAGE STRUCTURES OF t-BUTYL CHLORIDE AND 9D-t-BUTYL CHLORIDE DETERMINED BY GAS-PHASE ELECTRON DIFFRACTION.
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Wieser, J
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- 1971
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166. Quantifying the Hydration-Dependent Dynamics of Cu Migration and Activity in Zeolite Omega for the Partial Oxidation of Methane.
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Wieser J, Wardecki D, Fischer JWA, Newton MA, Dejoie C, Knorpp AJ, Hansen TC, Jeschke G, Rzepka P, and van Bokhoven JA
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Copper-exchanged zeolite omega (Cu-omega) is a potent material for the selective conversion of methane-to-methanol (MtM) via the oxygen looping approach. However, its performance exhibits substantial variation depending on the operational conditions. Under an isothermal temperature regime, Cu-omega demonstrates subdued activity below 230 °C, but experiences a remarkable increase in activity at 290 °C. Applying a high-temperature activation protocol at 450 °C causes a rapid deactivation of the material. This behavioral divergence is investigated by combining reactivity studies, neutron diffraction and in situ high-resolution anomalous X-ray powder diffraction (HR-AXRPD), as well as electron paramagnetic resonance spectroscopy, to reveal that the migration of Cu throughout the framework is the primary cause of these behaviors, which in turn is predominantly governed by the degree of hydration of the system. This work suggests that control over the Cu migration throughout the zeolite framework may be harnessed to significantly increase the activity of Cu-omega by generating more active sites for the MtM conversion. These results underscore the power of in situ HR-AXRPD for unraveling the behavior of materials under reaction conditions and suggest that a re-evaluation of Cu-zeolites priorly deemed inactive for the MtM conversion across a broader range of conditions and looping protocols may be warranted., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)
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- 2024
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167. Inpatient management of epidermolysis bullosa: Consensus-based hands-on instructions for neonates and postneonates.
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Abreu Molnar B, Levin L, Yun D, Morel K, Wiss K, Wieser J, Ward C, Trice H, Garcia-Romero MT, Stephenson A, Provost A, Price HN, Perman MJ, Moxon M, Moeves B, McCuaig CC, McCarthy C, Lucky AW, Levy ML, Lee M, Lara-Corrales I, Henner N, Halliburton N, Griffith E, Gorell E, Glick S, Eichenfield L, Collins C, Bruckner AL, Boulrice B, Bayliss S, Badger K, and Paller AS
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- Humans, Infant, Newborn, Hospitalization, Practice Guidelines as Topic, Infant, Female, Dermatology methods, Dermatology standards, Male, Delphi Technique, Epidermolysis Bullosa therapy, Consensus
- Abstract
Background: Epidermolysis bullosa (EB), characterized by skin fragility and blistering, often requires hospitalization. Training for inpatient management of EB is limited, with no unified recommendations available in North America., Objective: To develop consensus-derived best practices for hands-on inpatient management of EB in both the neonatal and postneonatal period., Methods: A modified Delphi method (expert-based input via 2 surveys and a final review) was implemented. Available guidelines from EB Clinical Research Consortium centers were analyzed to determine areas of focus and formulate statements to be voted on by EB Clinical Research Consortium members, experienced EB nurses, and select family members. Study participants evaluated statements using a Likert scale: statements with at least 70% agreement were accepted; statements with 30% or more disagreement were rejected., Results: Ten areas of focus were identified. Delphi participants included 15 dermatologists, 8 nurses, and 6 nonhealth care caregivers. Consensus was established on 103/119 neonatal statements and 105/122 postneonatal statements; no statements were rejected. Most recommendations applied to both age groups., Limitations: Recommendations may require adjustment based on individual patient's clinical context., Conclusion: Using the Delphi method, a consensus-derived resource for hospital-based health care professionals who manage patients with EB has been developed to improve the quality of inpatient care., Competing Interests: Conflicts of interest Dr Garcia-Romero has received the EBCRC grant and has been a speaker for Cerave Latinamerica and Carnot Mexico Laboratories. Dr Price’s’ conflicts of interest are Aegle (PI clinical trial), Rheacell (PI clinical trial) Krystal Biotech (consultant). Dr Perman has served as a consultant for Abeona. Dr Lucky has served as investigator for Krystal Pharma and Phoenicis. Dr McCuaig’s conflicts of interest are AbbVie, Bausch, Boehringer, Galderma, Incyte, J&J, Eli Lilly, Leo, Novartis, Oreal Pfizer, Sanofi, and Sun. Dr Gorell has served as a consultant for Krystal Biotech, Abeona Therapeutics, and Amryt Pharma. Dr Levy’s conflicts of interest are Abeona, Castle Creek, Krystal, and Rheacell. Dr Bruckner’s conflicts of interest are Abeona (consultant), Amryt (consultant and investigator), Castle Creek (consultant and investigator), Krystal Biotech (consultant), Phoenix Tissue Repair (investigator), Phoenicis (investigator), Rheacell (investigator), and TWi Bio (consultant). Dr Paller has been an investigator for AbbVie, Applied Pharma Research, Dermavant, Eli Lilly, Incyte, Janssen, Krystal, Regeneron, and UCB; a consultant for Aegerion Pharma, Azitra, BioCryst, Boehringer-Ingelheim, Bristol Myers Squibb, Eli Lilly, Janssen, Johnson & Johnson, Krystal, LEO Pharma, Novartis, Primus, Regeneron, Sanofi/Genzyme, Seanergy, TWI Biotechnology, and UCB; and on the data safety monitoring board for AbbVie, Abeona, Catawba, Galderma, and InMed., (Copyright © 2024 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.)
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- 2024
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168. Improved patient- and caregiver-reported outcomes distinguish tacrolimus 0.03% from crisaborole in children with atopic dermatitis.
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Ryan Wolf J, Chen A, Wieser J, Johnson B, Baughman L, Lee G, Pope E, Franco A, Love T, and Beck LA
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- Humans, Child, Female, Male, Child, Preschool, Severity of Illness Index, Pruritus drug therapy, Anxiety, Adolescent, Depression drug therapy, Sleep drug effects, Pain drug therapy, Immunosuppressive Agents therapeutic use, Dermatitis, Atopic drug therapy, Tacrolimus therapeutic use, Tacrolimus administration & dosage, Boron Compounds therapeutic use, Caregivers, Quality of Life, Patient Reported Outcome Measures, Bridged Bicyclo Compounds, Heterocyclic therapeutic use
- Abstract
Background: Atopic dermatitis (AD) is a chronic skin disease that affects 20% of children worldwide and is associated with low patient-reported quality of life (QoL). Crisaborole (CRIS) and tacrolimus 0.03% (TAC) are Food and Drug Administration (FDA)-approved topical treatments for mild to moderate AD with similar clinical efficacy. Utilization of patient-reported outcomes (PROs) may provide meaningful data on the impact of AD treatments on patients and caregivers. This study used PROs to monitor the impact of crisaborole (CRIS) and tacrolimus 0.03% (TAC) on children with mild/moderate atopic dermatitis (AD) and caregiver burden., Methods: This open-label study randomized 47 child-caregiver dyads to CRIS or TAC for 12 weeks. Disease severity, child quality of life (QoL), itch, pain interference, anxiety, depression, sleep, caregiver burden and caregiver QoL were assessed at baseline, 6 and 12 weeks., Results: A total of 36 dyads completed the study. Children (mean age = 8.0 ± 3.9 years) had mild baseline AD and were diverse by race (39% white; 36% Black) and gender (53% males). Caregivers were mostly female (78%; mean age = 37 ± 7.6 years). Both arms improved disease severity (Eczema Area and Severity Index) from baseline to 12 weeks (CRIS = -2.4 vs. TAC = -1.9). Within-arm analyses comparing baseline to 12 weeks revealed TAC, but not CRIS, improved all child and caregiver PROs except sleep (all p < 0.05)., Conclusions: Our results demonstrated that topical treatment for 12 weeks was more beneficial than 6 weeks, with TAC improving more PROs than CRIS. Future trials should implement PROs to fully understand the impact of AD treatments., (© 2024 European Academy of Dermatology and Venereology.)
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- 2024
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169. Healthcare systems collaborating to implement a shared decision-making tool in the electronic health record and build evidence on its adoption and use.
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Branda ME, Ridgeway JL, Mann D, Wieser J, Gomez Y, Dagoberg A, Nautiyal V, Jackson H, Jahn P, Yaple K, Khurana C, Gharai H, Giese B, Corcoran T, Montori V, and Montori VM
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Introduction: Shared decision-making (SDM) is a method of care by which patients and clinicians work together to co-create a plan of care. Electronic health record (EHR) integration of SDM tools may increase adoption of SDM. We conducted a "lightweight" integration of a freely available electronic SDM tool, CV Prevention Choice, within the EHRs of three healthcare systems. Here, we report how the healthcare systems collaborated to achieve integration., Methods: This work was conducted as part of a stepped wedge randomized pragmatic trial. CV Prevention Choice was developed using guidelines for HTML5-based web applications. Healthcare systems integrated the tool in their EHR using documentation the study team developed and refined with lessons learned after each system integrated the electronic SDM tool into their EHR. CV Prevention Choice integration populates the tool with individual patient data locally without sending protected health information between the EHR and the web. Data abstraction and secure transfer systems were developed to manage data collection to assess tool implementation and effectiveness outcomes., Results: Time to integrate CV Prevention Choice in the EHR was 12.1 weeks for the first system, 10.4 weeks for the second, and 9.7 weeks for the third. One system required two 1-hour meetings with study team members and two healthcare systems required a single 1-hour meeting. Healthcare system information technology teams collaborated by sharing information and offering improvements to documentation. Challenges included tracking CV Prevention Choice use for reporting and capture of combination medications. Data abstraction required refinements to address differences in how each healthcare system captured data elements., Conclusion: Targeted documentation on tool features and resource mapping supported collaboration of IT teams across healthcare systems, enabling them to integrate a web-based SDM tool with little additional research team effort or oversight. Their collaboration helped overcome difficulties integrating the web application and address challenges to data harmonization for trial outcome analyses., Competing Interests: The authors declare no conflicts of interest., (© 2024 Mayo Clinic. Learning Health Systems published by Wiley Periodicals LLC on behalf of University of Michigan.)
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- 2024
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170. Assessing the Productivity of the Direct Conversion of Methane-to-Methanol over Copper-Exchanged Zeolite Omega (MAZ) via Oxygen Looping.
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Wieser J, Knorpp AJ, Stoian DC, Rzepka P, Newton MA, and van Bokhoven JA
- Abstract
The methane-to-methanol (MtM) conversion via the oxygen looping approach using copper-exchanged zeolites has been extensively studied over the last decade. While a lot of research has focussed on maximizing yield and selectivity, little has been directed toward productivity-a metric far more meaningful for evaluating industrial potential. Using copper-exchanged zeolite omega (Cu-omega), a material highly active and selective for the MtM conversion using the isothermal oxygen looping approach, we show that this material exhibits unprecedented potential for industrial valorization. In doing so, we also present a novel methodology combining operando XAS and mass spectrometry for the screening of materials for the MtM conversion in oxygen looping mode., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)
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- 2023
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171. Assessing the interrelationship between stigma, social influence, and cervical cancer prevention in an urban underserved setting: An exploratory study.
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Peterson CE, Dykens JA, Weine SM, Holt HK, Fleurimont J, Hutten CG, Wieser J, Abuisneineh F, Awadalla S, Ongtengco NP, Gastala N, and Jasenof IG
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- Male, Humans, Female, Social Stigma, Delivery of Health Care, Uterine Cervical Neoplasms prevention & control, Papillomavirus Infections prevention & control, Papillomavirus Vaccines therapeutic use
- Abstract
In the US, incidence and mortality from cervical cancer disproportionately affects racial/ethnic minorities and low-income women. Despite affordable access to primary and secondary prevention measures at Federally Qualified Health Centers (FQHCs), Human Papillomavirus (HPV) vaccination and screening rates are low, suggesting the presence of non-financial barriers to uptake in this population. This explanatory sequential mixed-methods study sought to explore factors that influence the acceptability of cervical cancer prevention services among parents and legal guardians of vaccine-eligible girls attending an urban FQHC and to assess social influences related to cervical cancer prevention. Participants included eight mothers, one father, and two grandparents/legal guardians. Nine participants self-identified as Black/Afro-Caribbean, or African American, two as Latinx, and one as Native American. The quantitative data suggested discordance between participants' cervical cancer prevention knowledge and their practices. Most indicated that their daughters had received the HPV vaccine but were unsure about HPV transmission modes. Qualitative data revealed that participants were comfortable disclosing information on HPV infection and vaccination status, and most women were likely to share information related to cervical cancer testing and diagnosis. Few comments indicated personal stigma on the part of participants, but there was frequent expression of perceived public stigma (shaming and blaming women), gender differences (men are indifferent to risk), and distrust of the healthcare system. Findings highlight several concepts including the disharmony between knowledge and practice, prevalent perceived public stigma, cumbersome attitudes on the part of men regarding HPV and cervical cancer, and distrust of the healthcare system., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Peterson et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2022
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172. A first attempt at a holistic analysis of various influencing factors on the fish fauna in the Eastern European Alps.
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Schmölz K, Bottarin R, Felber A, Lassacher F, Lehne F, Mark W, Niederwanger M, Niedrist GH, Oberarzbacher S, Pelster B, Peron A, Persiano S, Schletterer M, Schwarzenberger R, Scotti A, Thaler M, Walde J, Wieser J, and Tasser E
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- Animals, Biomass, European Alpine Region, Fisheries, Rivers, Ecosystem, Fishes
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Fish are some of the most threatened vertebrates in the world due to their often-sensitive response to environmental changes. Major land-use changes in the European Alps have direct and indirect impacts on fish communities, and these impacts are expected to increase in the future. Therefore, the identification of factors that are associated with the distribution of fish communities is of great importance to develop guidelines for management, precautions and sustainable use of running waters. In this study, the relationship of various factors - landscape structure and land use, topography, morphology, hydrology, physical and chemical water characteristics, hormonally active substances, pesticides, food availability, fisheries and piscivores birds - with fish assemblages are analysed. Field data from 81 stream sections from 2001 metres above sea level (m.a.s.l.) down to 219 m.a.s.l. are used in the study. The results reveal that the number of fish species has a strong association with topographic characteristics in the catchment area as well as with landscape configuration. Fish abundance and biomass are associated mostly with land-use type, hydrology, morphology as well as topography. In addition, there are indirect connections between fish abundance and biomass through land-use type, topography, water properties and hydromorphology. The results clearly indicate that not a single factor, but a multitude of factors are associated with the fish communities in the Eastern European Alps., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)
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- 2022
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173. Pathogens That Cause Acute Febrile Illness Among Children and Adolescents in Burkina Faso, Madagascar, and Sudan.
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Marks F, Liu J, Soura AB, Gasmelseed N, Operario DJ, Grundy B, Wieser J, Gratz J, Meyer CG, Im J, Lim JK, von Kalckreuth V, Cruz Espinoza LM, Konings F, Jeon HJ, Rakotozandrindrainy R, Zhang J, Panzner U, and Houpt E
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- Adolescent, Adult, Burkina Faso epidemiology, Child, Child, Preschool, Humans, Infant, Infant, Newborn, Madagascar epidemiology, Sudan, Young Adult, Communicable Diseases, Fever epidemiology, Fever etiology
- Abstract
Background: The etiology and optimal clinical management of acute febrile illness (AFI) is poorly understood., Methods: Blood samples taken from study participants with acute fever (≥37.5°C) or a history of fever and recruited into the previous Typhoid Fever Surveillance in Africa (TSAP) study were evaluated using a polymerase chain reaction (PCR)-based TaqMan-Array Card designed to detect a panel of bacterial, viral, and parasitic pathogens. Clinical metadata were also assessed., Results: A total of 615 blood samples available for analysis originated from Burkina Faso (n = 53), Madagascar (n = 364), and Sudan (n = 198) and were taken from participants ranging in age from 0-19 years. Through the TaqMan-Array Card, at least 1 pathogen was detected in 62% (33 of 53), 24% (86 of 364), and 60% (118 of 198) of specimens from Burkina Faso, Madagascar, and Sudan, respectively. The leading identified pathogen overall was Plasmodium spp., accounting for 47% (25 of 53), 2.2% (8 of 364), and 45% (90 of 198) of AFI at the respective sites. In Madagascar, dengue virus was the most prevalent pathogen (10.2%). Overall, 69% (357 of 516) of patients with clinical diagnoses of malaria, respiratory infection, or gastrointestinal infection were prescribed a World Health Organization guideline-recommended empiric antibiotic, whereas only 45% (106 of 237) of patients with pathogens detected were treated with an antibiotic exerting likely activity., Conclusions: A PCR approach for identifying multiple bacterial, viral, and parasitic pathogens in whole blood unveiled a diversity of previously undetected pathogens in AFI cases and carries implications for the appropriate management of this common syndrome., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America.)
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- 2021
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174. Rapid Gas Hydrate Formation-Evaluation of Three Reactor Concepts and Feasibility Study.
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Filarsky F, Wieser J, and Schultz HJ
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Gas hydrates show great potential with regard to various technical applications, such as gas conditioning, separation and storage. Hence, there has been an increased interest in applied gas hydrate research worldwide in recent years. This paper describes the development of an energetically promising, highly attractive rapid gas hydrate production process that enables the instantaneous conditioning and storage of gases in the form of solid hydrates, as an alternative to costly established processes, such as, for example, cryogenic demethanization. In the first step of the investigations, three different reactor concepts for rapid hydrate formation were evaluated. It could be shown that coupled spraying with stirring provided the fastest hydrate formation and highest gas uptakes in the hydrate phase. In the second step, extensive experimental series were executed, using various different gas compositions on the example of synthetic natural gas mixtures containing methane, ethane and propane. Methane is eliminated from the gas phase and stored in gas hydrates. The experiments were conducted under moderate conditions (8 bar(g), 9-14 °C), using tetrahydrofuran as a thermodynamic promoter in a stoichiometric concentration of 5.56 mole%. High storage capacities, formation rates and separation efficiencies were achieved at moderate operation conditions supported by rough economic considerations, successfully showing the feasibility of this innovative concept. An adapted McCabe-Thiele diagram was created to approximately determine the necessary theoretical separation stage numbers for high purity gas separation requirements.
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- 2021
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175. Dynamin 2 is required for GPVI signaling and platelet hemostatic function in mice.
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Eaton N, Drew C, Wieser J, Munday AD, and Falet H
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- Animals, Dynamin II genetics, Dynamin II pharmacology, Hemostasis, Mice, Platelet Activation, Platelet Membrane Glycoproteins genetics, Blood Platelets, Hemostatics pharmacology
- Abstract
Receptor-mediated endocytosis, which contributes to a wide range of cellular functions, including receptor signaling, cell adhesion, and migration, requires endocytic vesicle release by the large GTPase dynamin 2. Here, the role of dynamin 2 was investigated in platelet hemostatic function using both pharmacological and genetic approaches. Dnm2
fl/fl Pf4-Cre ( Dnm2Plt - / - ) mice specifically lacking dynamin 2 within the platelet lineage developed severe thrombocytopenia and bleeding diathesis and Dnm2Plt - / - platelets adhered poorly to collagen under arterial shear rates. Signaling via the collagen receptor GPVI was impaired in platelets treated with the dynamin GTPase inhibitor dynasore, as evidenced by poor protein tyrosine phosphorylation, including that of the proximal tyrosine kinase Lyn on its activating tyrosine 396 residue. Platelet stimulation via GPVI resulted in a slight decrease in GPVI, which was maintained by dynasore treatment. Dynasore-treated platelets had attenuated function when stimulated via GPVI, as evidenced by reduced GPIbα downregulation, α-granule release, integrin αIIbβ3 activation, and spreading onto immobilized fibrinogen. By contrast, responses to the G-protein coupled receptor agonist thrombin were minimally affected by dynasore treatment. GPVI expression was severely reduced in Dnm2Plt-/- platelets, which were dysfunctional in response to stimulation via GPVI, and to a lesser extent to thrombin. Dnm2Plt-/- platelets lacked fibrinogen in their α-granules, but retained von Willebrand factor. Taken together, the data show that dynamin 2 plays a proximal role in signaling via the collagen receptor GPVI and is required for fibrinogen uptake and normal platelet hemostatic function., (Copyright© 2020 Ferrata Storti Foundation.)- Published
- 2020
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176. The Adult Murine Intestine is Dependent on Constitutive Laminin-γ1 Synthesis.
- Author
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Fields B, DeLaForest A, Zogg M, May J, Hagen C, Komnick K, Wieser J, Lundberg A, Weiler H, Battle MA, and Carlson KS
- Subjects
- Animals, Basement Membrane growth & development, Basement Membrane metabolism, Female, Laminin biosynthesis, Liver metabolism, Mice, Embryonic Development genetics, Intestines growth & development, Laminin genetics
- Abstract
Laminin-γ1 is required for early embryonic development; however, the need for laminin-γ1 synthesis in adulthood is unknown. A global and inducible mouse model of laminin-γ1 deficiency was generated to address this question. Genetic ablation of the Lamc1 gene in adult mice was rapidly lethal. Despite global Lamc1 gene deletion in tamoxifen-induced mutant mice, there was minimal change in total cardiac, pulmonary, hepatic or renal laminin protein. In contrast, laminin-γ1 was significantly depleted in the small intestines, which showed crypt hyperplasia and dissociation of villous epithelium from adjacent mesenchyme. We conclude that the physiologic requirement for laminin-γ1 synthesis in adult mice is dependent on a tissue-specific basal rate of laminin-γ1 turnover that results in rapid depletion of laminin-γ1 in the intestine.
- Published
- 2019
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177. Comparison of Stroke Outcomes of Hub and Spoke Hospital Treated Patients in Mayo Clinic Telestroke Program.
- Author
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Demaerschalk BM, Boyd EL, Barrett KM, Gamble DM, Sonchik S, Comer MM, Wieser J, Hentz JG J, Fitz-Patrick D, and Chang YH
- Subjects
- Aged, Aged, 80 and over, Anticholesteremic Agents therapeutic use, Anticoagulants therapeutic use, Clinical Decision-Making, Delivery of Health Care, Integrated, Disability Evaluation, Female, Fibrinolytic Agents adverse effects, Humans, Infusions, Intravenous, Intracranial Hemorrhages chemically induced, Length of Stay, Male, Middle Aged, Patient Selection, Program Evaluation, Quality Improvement, Quality Indicators, Health Care, Recovery of Function, Retrospective Studies, Risk Factors, Stroke diagnosis, Stroke mortality, Stroke physiopathology, Time Factors, Time-to-Treatment, Tissue Plasminogen Activator adverse effects, Treatment Outcome, Fibrinolytic Agents administration & dosage, Stroke drug therapy, Telemedicine methods, Thrombolytic Therapy adverse effects, Thrombolytic Therapy mortality, Tissue Plasminogen Activator administration & dosage
- Abstract
Purpose: To examine telemedicine as it applies to acute ischemic stroke care at a spoke hospital and the effect on patient outcomes, including the timeliness of response, quality of care, safety, morbidity, and mortality when compared to standard hub hospital stroke center care., Methods: Retrospective review of prospectively entered quality/performance stroke/telestroke patient catalog data were completed for 1000 adult patients who presented with an acute ischemic stroke to the Mayo Clinic Hospitals (500 patients) or to one of thirteen Mayo Clinic affiliated telestroke spoke hospitals in the regions (500 patients). The primary outcome of interest was the percentage of accurate decision making for eligibility of IV alteplase administration assessed by blinded adjudication and the secondary outcomes pertained to complications, discharge parameters, and standard quality metrics., Results: There was no difference in the spoke hospital versus hub hospital groups in identifying and making the correct decision regarding which patients were eligible for IV alteplase administration (96% [95% confidence interval (CI): 94%-97%] versus 97% [95% CI: 95%-98%]; P = 0.32). There was no difference among the groups in proportion receiving IV alteplase, sustaining symptomatic intracranial hemorrhage, and mortality. Patients in the spoke group were less likely to have a favorable outcome at discharge, as defined by National Institutes of Health Stroke Scale (NIHSS): 0-1 or mRS: 0-1 or Glasgow Outcome Scale (GOS): 0-1 (21% versus, 35%; P < 0.001), were less likely to have venous thromboembolism prophylaxis (46% versus 63%; P < 0.01), were less likely to have received antithrombotic therapy (85% versus 90%; P = .02), were less likely to be discharged on anticoagulation when indicated (56% versus 64%; P = .01), and were less likely to be prescribed cholesterol reducing treatment (68% versus 72%; P < .001). The initial acute care hospital length of stay was longer for the spoke hospital group by one day (median: 4 versus 3; P < .001)., Conclusion: The key findings were that evidence-based stroke thrombolysis eligibility decision making, thrombolysis administration, and thrombolysis emergency stroke metrics were uniformly excellent for the spoke hospital group when compared to the standard hub hospital group. However, evidence-based stroke hospitalization and discharge metrics were inferior for the spoke hospital group when compared to the standard hub hospital., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
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178. Determination of Hydrogen Density by Swift Heavy Ions.
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Xu G, Barriga-Carrasco MD, Blazevic A, Borovkov B, Casas D, Cistakov K, Gavrilin R, Iberler M, Jacoby J, Loisch G, Morales R, Mäder R, Qin SX, Rienecker T, Rosmej O, Savin S, Schönlein A, Weyrich K, Wiechula J, Wieser J, Xiao GQ, and Zhao YT
- Abstract
A novel method to determine the total hydrogen density and, accordingly, a precise plasma temperature in a lowly ionized hydrogen plasma is described. The key to the method is to analyze the energy loss of swift heavy ions interacting with the respective bound and free electrons of the plasma. A slowly developing and lowly ionized hydrogen theta-pinch plasma is prepared. A Boltzmann plot of the hydrogen Balmer series and the Stark broadening of the H_{β} line preliminarily defines the plasma with a free electron density of (1.9±0.1)×10^{16} cm^{-3} and a free electron temperature of 0.8-1.3 eV. The temperature uncertainty results in a wide hydrogen density, ranging from 2.3×10^{16} to 7.8×10^{18} cm^{-3}. A 108 MHz pulsed beam of ^{48}Ca^{10+} with a velocity of 3.652 MeV/u is used as a probe to measure the total energy loss of the beam ions. Subtracting the calculated energy loss due to free electrons, the energy loss due to bound electrons is obtained, which linearly depends on the bound electron density. The total hydrogen density is thus determined as (1.9±0.7)×10^{17} cm^{-3}, and the free electron temperature can be precisely derived as 1.01±0.04 eV. This method should prove useful in many studies, e.g., inertial confinement fusion or warm dense matter.
- Published
- 2017
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179. Impact of cannabis use on prefrontal and parietal cortex gyrification and surface area in adolescents and emerging adults.
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Shollenbarger SG, Price J, Wieser J, and Lisdahl K
- Subjects
- Adolescent, Adult, Cognition drug effects, Female, Functional Laterality, Gyrus Cinguli pathology, Humans, Magnetic Resonance Imaging, Male, Memory, Short-Term drug effects, Neuropsychological Tests, Parietal Lobe pathology, Prefrontal Cortex pathology, Psychomotor Performance drug effects, Self Report, Social Perception, Young Adult, Gyrus Cinguli drug effects, Gyrus Cinguli growth & development, Marijuana Abuse pathology, Parietal Lobe drug effects, Parietal Lobe growth & development, Prefrontal Cortex drug effects, Prefrontal Cortex growth & development
- Abstract
Background: Regions undergoing maturation with CB1 receptors may be at increased risk for cannabis-induced alterations. Here, we examine the relationships between cannabis use and prefrontal (PFC) and inferior parietal gyrification and surface area (SA) in youth., Methods: Participants included 33 cannabis users and 35 controls (ages 18-25). Exclusions included co-morbid psychiatric/neurologic disorders and heavy other drug use. Multiple regressions and Pearson r correlations examined the effects of cannabis use on gyrification, SA and cognition., Results: Cannabis use was associated with decreased gyrification in: ventral-medial PFC (RH: [FDR corrected p=.02], LH: [FDR corrected p=.02]); medial PFC (RH: [FDR corrected p=.02], LH: [FDR corrected p=.02]); and frontal poles (RH: [FDR corrected p=.02], LH: [FDR corrected p=.02]). No differences were observed in bilateral hemispheres, PFC, dorsolateral, ventrolateral, or inferior parietal ROIs. Cannabis use was associated with marginally decreased SA in left: medial PFC [FDR corrected p=.09], and ventral lateral PFC: [FDR corrected p=.09]. In cannabis users, increased gyrification was associated with improved working-memory performance in right medial (p=.003), ventral-medial (p=.03), and frontal pole ROIs (p=.007)., Conclusions: Cannabis use was associated with reduced gyrification in PFC regions implicated in self-referential thought and social cognition. Results suggest that these gyrification characteristics may have cognitive implications., (Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2015
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180. Effects of marijuana use on prefrontal and parietal volumes and cognition in emerging adults.
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Price JS, McQueeny T, Shollenbarger S, Browning EL, Wieser J, and Lisdahl KM
- Subjects
- Adolescent, Adult, Executive Function drug effects, Female, Humans, Male, Marijuana Abuse physiopathology, Marijuana Abuse psychology, Marijuana Smoking psychology, Organ Size drug effects, Parietal Lobe pathology, Prefrontal Cortex pathology, Sex Characteristics, Young Adult, Cannabis, Cognition drug effects, Marijuana Abuse pathology, Marijuana Smoking pathology, Parietal Lobe drug effects, Prefrontal Cortex drug effects
- Abstract
Rationale: Chronic marijuana (MJ) use among adolescents has been associated with structural and functional abnormalities, particularly in developing regions responsible for higher order cognition., Objectives: This study investigated prefrontal (PFC) and parietal volumes and executive function in emerging adult MJ users and explored potential gender differences., Methods: Participants (ages 18-25) were 27 MJ users and 32 controls without neurologic or psychiatric disorders or heavy other drug use. A series of multiple regressions examined whether group status, past year MJ use, and their interactions with gender predicted ROI volumes. Post hoc analyses consisted of brain-behavior correlations between volumes and cognitive variables and Fisher's z tests to assess group differences., Results: MJ users demonstrated significantly smaller medial orbitofrontal (mOFC; p = 0.004, FDR p = 0.024) and inferior parietal volumes (p = 0.04, FDR p = 0.12); follow-up regressions found that increased past year MJ use did not significantly dose-dependently predict smaller mOFC volume in a sub-sample of individuals with at least one past year MJ use. There were no significant gender interactions. There was a significant brain-behavior difference by group, such that smaller mOFC volumes were associated with poorer complex attention for MJ users (p < 0.05)., Conclusions: Smaller mOFC volumes among MJ users suggest disruption of typical neurodevelopmental processes associated with regular MJ use for both genders. These results highlight the need for longitudinal, multi-modal imaging studies providing clearer information on timing of neurodevelopmental processes and neurocognitive impacts of youth MJ initiation.
- Published
- 2015
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181. Poorer frontolimbic white matter integrity is associated with chronic cannabis use, FAAH genotype, and increased depressive and apathy symptoms in adolescents and young adults.
- Author
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Shollenbarger SG, Price J, Wieser J, and Lisdahl K
- Subjects
- Adolescent, Adult, Female, Frontal Lobe pathology, Genotype, Humans, Limbic System pathology, Magnetic Resonance Imaging, Male, White Matter pathology, Young Adult, Amidohydrolases genetics, Apathy physiology, Cannabis adverse effects, Depression physiopathology, Frontal Lobe drug effects, Limbic System drug effects, White Matter drug effects
- Abstract
Background: The heaviest period of cannabis use coincides with ongoing white matter (WM) maturation. Further, cannabis-related changes may be moderated by FAAH genotype (rs324420). We examined the association between cannabis use and FAAH genotype on frontolimbic WM integrity in adolescents and emerging adults. We then tested whether observed WM abnormalities were linked with depressive or apathy symptoms., Methods: Participants included 37 cannabis users and 37 healthy controls (33 female; ages 18-25). Multiple regressions examined the independent and interactive effects of variables on WM integrity., Results: Regular cannabis users demonstrated reduced WM integrity in the bilateral uncinate fasciculus (UNC) (MD, right: p = .009 and left: p = .009; FA, right: p = .04 and left: p = .03) and forceps minor (fMinor) (MD, p = .03) compared to healthy controls. Marginally reduced WM integrity in the cannabis users was found in the left anterior thalamic radiation (ATR) (FA, p = .08). Cannabis group ∗ FAAH genotype interaction predicted WM integrity in bilateral ATR (FA, right: p = .05 and left: p = .001) and fMinor (FA, p = .02). In cannabis users, poorer WM integrity was correlated with increased symptoms of depression and apathy in bilateral ATR and UNC., Conclusions: Consistent with prior findings, cannabis use was associated with reduced frontolimbic WM integrity. WM integrity was also moderated by FAAH genotype, in that cannabis-using FAAH C/C carriers and A carrying controls had reduced WM integrity compared to control C/C carriers. Observed frontolimbic white matter abnormalities were linked with increased depressive and apathy symptoms in the cannabis users.
- Published
- 2015
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182. M6P/IGF2R modulates the invasiveness of liver cells via its capacity to bind mannose 6-phosphate residues.
- Author
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Puxbaum V, Nimmerfall E, Bäuerl C, Taub N, Blaas PM, Wieser J, Mikula M, Mikulits W, Ng KM, Yeoh GC, and Mach L
- Subjects
- Animals, Cell Line, Cell Movement, Cell Proliferation, Humans, Leucine analogs & derivatives, Leucine pharmacology, Lysosomes enzymology, Mice, Neoplasm Invasiveness, Protein Binding, Rats, Hepatocytes pathology, Liver Neoplasms pathology, Mannosephosphates metabolism, Receptor, IGF Type 2 physiology
- Abstract
Background & Aims: The mannose 6-phosphate/insulin-like growth factor II receptor (M6P/IGF2R), a multifunctional protein, plays a central role in intracellular targeting of lysosomal enzymes and control of insulin-like growth factor II (IGF-II) bioactivity. Importantly, the gene encoding this receptor is frequently inactivated in a wide range of malignant tumors including hepatocellular carcinomas. Thus, M6P/IGF2R is considered a putative liver tumor suppressor. The aim of this study was to establish the impact of the receptor on the invasive properties of liver cells., Methods: Reconstitution experiments were performed by expression of wild type and mutant M6P/IGF2R in receptor-deficient FRL14 fetal rat liver cells. RNA interference was used to induce M6P/IGF2R downregulation in receptor-positive MIM-1-4 mouse hepatocytes., Results: We show that the M6P/IGF2R status exerts a strong impact on the invasiveness of tumorigenic rodent liver cells. M6P/IGF2R-deficient fetal rat liver cells hypersecrete lysosomal cathepsins and penetrate extracellular matrix barriers in a cathepsin-dependent manner. Forced expression of M6P/IGF2R restores intracellular transport of cathepsins to lysosomes and concomitantly reduces the tumorigenicity and invasive potential of these cells. Conversely, M6P/IGF2R knock-down in receptor-positive mouse hepatocytes causes increased cathepsin secretion as well as enhanced cell motility and invasiveness. We also demonstrate that functional M6P-binding sites are important for the anti-invasive properties of M6P/IGF2R, whereas the capacity to bind IGF-II is dispensable for the anti-invasive activity of the receptor in liver cells., Conclusions: M6P/IGF2R restricts liver cell invasion by preventing the pericellular action of M6P-modified proteins., (Copyright © 2012 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)
- Published
- 2012
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183. Pedaling alters the excitability and modulation of vastus medialis H-reflexes after stroke.
- Author
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Fuchs DP, Sanghvi N, Wieser J, and Schindler-Ivens S
- Subjects
- Adult, Electromyography methods, Exercise Test methods, Female, Humans, Male, Middle Aged, Paresis etiology, Paresis rehabilitation, Stroke complications, Stroke Rehabilitation, Bicycling physiology, H-Reflex physiology, Paresis physiopathology, Quadriceps Muscle physiology, Stroke physiopathology
- Abstract
Objective: Individuals post-stroke display abnormal Group Ia reflex excitability. Pedaling has been shown to reduce Group Ia reflexes and to normalize the relationship between EMG and reflex amplitude in the paretic soleus (SO). The purpose of this study was to determine whether these changes extend to the paretic quadriceps., Methods: H-reflexes were used to examine Group Ia reflex excitability of the vastus medialis (VM). H-reflexes were elicited in paretic (n=13) and neurologically intact (n=13) individuals at 11 positions in the pedaling cycle and during static knee extension at comparable limb positions and levels of VM EMG., Results: VM H-reflexes were abnormally elevated in the paretic limb of stroke survivors. During static muscle activation, H-reflex amplitude did not change with the level of background VM activity. Pedaling reduced the amplitude of paretic VM H-reflexes and restored the normal relationship between VM EMG and H-reflex amplitude., Conclusions: Pedaling-induced changes in Group Ia reflex excitability that have been reported for the paretic SO are evident in the paretic VM. Pedaling may have a generalized effect on lower extremity Group Ia reflexes post-stroke., Significance: Pedaling may be therapeutic for reducing Group Ia reflexes after stroke., (Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2011
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184. Real-time trace detection of security-relevant compounds in complex sample matrices by thermal desorption-single photon ionization-ion trap mass spectrometry (TD-SPI-ITMS).
- Author
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Schramm E, Hölzer J, Pütz M, Schulte-Ladbeck R, Schultze R, Sklorz M, Ulrich A, Wieser J, and Zimmermann R
- Abstract
For the detection of security-relevant substances at low concentrations in complex matrices, coupling of thermal desorption-single photon ionization-ion trap mass spectrometry (TD-SPI-ITMS) was successfully tested. The main advantage of taking solid samples with a wipe pad followed by thermal desorption is the low detection limit by enhanced vapor pressure. Single photon ionization is a soft ionization technique which reduces the target ion fragmentation and shields bulk components with high ionization energies (IE) like nitrogen yielding to clearly arranged mass spectra with significant high mass peaks. To obtain low false-positive and false-negative rates, especially necessary for security-relevant substances, the ion trap mass spectrometer allows identification of signals with MS/MS studies. In this concept, the soft ionization technique fits well with the MS/MS studies, as peaks with high masses are generated yielding significant MS/MS fragments. For the ionization, photon energies between about 8 eV (155 nm) and 12 eV (103 nm) were generated with electron-beam-pumped rare gas excimer lamps (EBEL). Depending on the rare gas used, light with different photon energy is generated, adapted to the substances of interest. So, even most narcotics, having relatively low IEs, can be ionized with 8.4 eV photons without massive fragmentation. For most explosives, photons with higher energy must be used as their IEs are higher. In this work, a mobile setup with a commercial ion trap mass spectrometer has been developed and tested. Even a first real-scenario measurement campaign was accomplished successfully proving the field-suitability of the system.
- Published
- 2009
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185. Conformational polymorphism in aripiprazole: Preparation, stability and structure of five modifications.
- Author
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Braun DE, Gelbrich T, Kahlenberg V, Tessadri R, Wieser J, and Griesser UJ
- Subjects
- Antipsychotic Agents chemical synthesis, Aripiprazole, Calorimetry, Differential Scanning, Crystallization, Crystallography, X-Ray, Humans, Kinetics, Molecular Conformation, Piperazines chemical synthesis, Quinolones chemical synthesis, Solvents chemistry, Spectrophotometry, Infrared, Spectrum Analysis, Raman, Thermodynamics, Antipsychotic Agents chemistry, Piperazines chemistry, Quinolones chemistry
- Abstract
Five phase-pure modifications of the antipsychotic drug aripiprazole were prepared and characterized by thermal analysis, vibrational spectroscopy and X-ray diffractometry. All modifications can be produced from solvents, form I additionally by heating of form X degrees to approximately 120 degrees C (solid-solid transformation) and form III by crystallization from the melt. Thermodynamic relationships between the polymorphs were evaluated on the basis of thermochemical data and visualized in a semi-schematic energy/temperature diagram. At least six of the ten polymorphic pairs are enantiotropically and two monotropically related. Form X degrees is the thermodynamically stable modification at 20 degrees C, form II is stable in a window from about 62-77 degrees C, and form I above 80 degrees C (high-temperature form). Forms III and IV are triclinic ($P\overline 1$), I and X degrees are monoclinic (P2(1)) and form II orthorhombic (Pna2(1)). Each polymorph exhibits a distinct molecular conformation, and there are two fundamental N-H$\cdots$O hydrogen bond synthons (catemers and dimers). Hirshfeld surface analysis was employed to display differences in intermolecular short contacts. A high kinetic stability was observed for three metastable polymorphs which can be categorized as suitable candidates for the development of solid dosage forms., ((c) 2008 Wiley-Liss, Inc.)
- Published
- 2009
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186. Trace detection of organic compounds in complex sample matrixes by single photon ionization ion trap mass spectrometry: real-time detection of security-relevant compounds and online analysis of the coffee-roasting process.
- Author
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Schramm E, Kürten A, Hölzer J, Mitschke S, Mühlberger F, Sklorz M, Wieser J, Ulrich A, Pütz M, Schulte-Ladbeck R, Schultze R, Curtius J, Borrmann S, and Zimmermann R
- Abstract
An in-house-built ion trap mass spectrometer combined with a soft ionization source has been set up and tested. As ionization source, an electron beam pumped vacuum UV (VUV) excimer lamp (EBEL) was used for single-photon ionization. It was shown that soft ionization allows the reduction of fragmentation of the target analytes and the suppression of most matrix components. Therefore, the combination of photon ionization with the tandem mass spectrometry (MS/MS) capability of an ion trap yields a powerful tool for molecular ion peak detection and identification of organic trace compounds in complex matrixes. This setup was successfully tested for two different applications. The first one is the detection of security-relevant substances like explosives, narcotics, and chemical warfare agents. One test substance from each of these groups was chosen and detected successfully with single photon ionization ion trap mass spectrometry (SPI-ITMS) MS/MS measurements. Additionally, first tests were performed, demonstrating that this method is not influenced by matrix compounds. The second field of application is the detection of process gases. Here, exhaust gas from coffee roasting was analyzed in real time, and some of its compounds were identified using MS/MS studies.
- Published
- 2009
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187. Soleus H-reflex excitability during pedaling post-stroke.
- Author
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Schindler-Ivens S, Brown DA, Lewis GN, Nielsen JB, Ondishko KL, and Wieser J
- Subjects
- Adult, Bicycling, Equipment Design, Female, Humans, Male, Middle Aged, Paresis etiology, Reference Values, Stroke physiopathology, Walking, H-Reflex, Motor Activity physiology, Muscle, Skeletal physiology, Paresis physiopathology
- Abstract
A major contributor to impaired locomotion post-stroke is abnormal phasing of paretic muscle activity, but the mechanisms remain unclear. Previous studies have shown that, in the paretic limb of people post-stroke, Group Ia reflexes are abnormally elevated and fail to decrease in amplitude during locomotion. Hence, we hypothesized that inappropriate muscle phasing may be associated with enhanced transmission in the monosynaptic Group Ia afferent pathway. Soleus (SO) H-reflexes were used to examine transmission in the Group Ia afferent pathway to SO motor neurons during pedaling, a locomotor task in which abnormal muscle phasing is evident. Our hypothesis predicted that H-reflexes would be elevated during the flexion phase of pedaling where inappropriate SO activity occurs. H-reflexes were elicited in paretic (n = 13) and neurologically intact (NI, n = 26) individuals at 11 different positions in the pedaling cycle and during tonic plantar flexion at comparable limb positions and levels of SO EMG. In both groups, SO H-reflexes were smaller during pedaling as compared to matched tonic plantar flexion. In the NI group, but not the paretic group, SO H-reflex amplitude was significantly modulated across the pedaling cycle. H-reflexes were large during extension and small during flexion. Reduced H-reflex modulation post-stroke was associated with the level of neuromuscular impairment as indicated by Fugl-Meyer score. However, regardless of impairment level, stroke subjects displayed H-reflex suppression during the flexion phase of pedaling. After correcting for the level of background muscle activity, H-reflexes were found to be larger in paretic as compared to NI individuals, regardless of the phase of the pedaling cycle. We conclude that Group Ia afferent transmission is enhanced in the paretic SO of people post-stroke as compared to NI individuals. However, contrary to our hypothesis, enhanced transmission in the Group Ia monosynaptic spinal pathway is not specifically associated with extraneous extensor muscle activity during the flexion phase of pedaling and is unlikely to account for abnormal locomotor muscle phasing post-stroke. This result is important because it suggests that, despite the presence of hyperactive monosynaptic reflexes post-stroke, this impairment may not make an important contribution to abnormal locomotor muscle activity.
- Published
- 2008
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188. The 46-kDa mannose 6-phosphate receptor does not depend on endosomal acidification for delivery of hydrolases to lysosomes.
- Author
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Probst OC, Ton P, Svoboda B, Gannon A, Schuhmann W, Wieser J, Pohlmann R, and Mach L
- Subjects
- 3T3-L1 Cells, Animals, Cathepsin B metabolism, Cathepsin D metabolism, Cathepsin L, Cathepsins metabolism, Cells, Cultured, Cysteine Endopeptidases metabolism, Glycosylation, Humans, Hydrogen-Ion Concentration, Ionophores pharmacology, Lysosomes drug effects, Mice, Mice, Knockout, Monensin pharmacology, NIH 3T3 Cells, Protein Transport drug effects, Receptor, IGF Type 2 genetics, Signal Transduction, Tissue Distribution, Endosomes chemistry, Hydrolases metabolism, Lysosomes enzymology, Receptor, IGF Type 2 physiology
- Abstract
In mammalian cells, the mannose 6-phosphate receptor pathway accounts for the transport of most soluble acid hydrolases to lysosomes. It is believed that dissociation of mannose 6-phosphate receptors and their ligands is entirely driven by the acidic environment in endosomal compartments. Indeed, pH-perturbing substances such as ammonium chloride and monensin have been shown to inhibit lysosomal enzyme targeting in cells that express both known mannose 6-phosphate receptors. We now demonstrate that ammonium chloride and monensin exert modest effects on the intracellular retention of lysosomal hydrolases in murine cells that synthesize only the 46-kDa mannose 6-phosphate receptor. Neither ammonium chloride nor monensin induces changes to the subcellular localization of lysosomal hydrolases and the 46-kDa mannose 6-phosphate receptor in these cells. This suggests that endosomal dissociation of the receptor and its ligands still occurs in the presence of these agents. We conclude that the murine 46-kDa mannose 6-phosphate receptor has the capacity to deliver its cargo proteins to lysosomes even in the absence of endosomal acidification.
- Published
- 2006
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189. Energy-transfer processes in neon-hydrogen mixtures excited by electron beams.
- Author
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Morozov A, Krücken R, Ulrich A, Wieser J, and McCarthy T
- Abstract
Energy- and charge-transfer processes in neon-hydrogen mixtures (500-1400 hPa neon and 0.001-3 hPa hydrogen partial pressures) excited by a pulsed low-energy (approximately 10 keV) electron beam were investigated using time-resolved spectroscopy. Time spectra of the hydrogen Lyman-alpha line, neon excimer emission (second continuum), and neon atomic lines (3p-3s transitions) were recorded. The time-integrated intensity of the Lyman-alpha emission was measured for the same range of gas mixtures. It is shown that direct energy transfer from Ne*2 excimers and neon atoms in the four lowest excited states as well as recombination of H3+ ions are the main channels populating atomic hydrogen in the n=2 state. A rate constant of (4.2+/-1.4)x10(-11) cm3 s(-1) was obtained for the charge transfer from Ne2+ ions to molecular hydrogen. A lower limit for the depopulation rate constant of Ne*2 excimers by molecular hydrogen (combination of energy transfer and ionization) was found to be 1.0 x 10(-10) cm3 s(-1).
- Published
- 2005
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190. Single photon ionization time-of-flight mass spectrometry with a pulsed electron beam pumped excimer VUV lamp for on-line gas analysis: setup and first results on cigarette smoke and human breath.
- Author
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Mühlberger F, Streibel T, Wieser J, Ulrich A, and Zimmermann R
- Subjects
- Humans, Ions chemistry, Molecular Structure, Respiration, Time Factors, Electrons, Mass Spectrometry instrumentation, Mass Spectrometry methods, Online Systems instrumentation, Smoke analysis, Nicotiana chemistry, Ultraviolet Rays
- Abstract
Single-photon ionization (SPI) using vacuum ultraviolet (VUV) light produced by an electron beam pumped rare gas excimer source has been coupled to a compact and mobile time-of-flight mass spectrometer (TOFMS). The novel device enables real-time on-line monitoring of organic trace substances in complex gaseous matrixes down to the ppb range. The pulsed VUV radiation of the light source is employed for SPI in the ion source of the TOFMS. Ion extraction is also carried out in a pulsed mode with a short time delay with respect to ionization. The experimental setup of the interface VUV light source/time-of-flight mass spectrometer is described, and the novel SPI-TOFMS system is characterized by means of standard calibration gases. Limits of detection down to 50 ppb for aliphatic and aromatic hydrocarbons were achieved. First on-line applications comprised real-time measurements of aromatic and aliphatic trace compounds in mainstream cigarette smoke, which represents a highly dynamic fluctuating gaseous matrix. Time resolution was sufficient to monitor the smoking process on a puff-by-puff resolved basis. Furthermore, human breath analysis has been carried out to detect differences in the breath of a smoker and a nonsmoker, respectively. Several well-known biomarkers for smoke could be identified in the smoker's breath. The possibility for even shorter measurement times while maintaining the achieved sensitivity makes this new device a promising tool for on-line analysis of organic trace compounds in process gases or biological systems.
- Published
- 2005
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191. Single-photon ionization quadrupole mass spectrometry with an electron beam pumped excimer light source.
- Author
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Mühlberger F, Wieser J, Morozov A, Ulrich A, and Zimmermann R
- Abstract
The application of soft ionization methods for mass spectrometry (MS), such as single-photon ionization (SPI) using vacuum ultraviolet (VUV) light, provides powerful analytical instrumentation for real-time on-line monitoring of organic substances in gaseous matrixes. A compact and mobile quadrupole mass spectrometer (QMS) system using a novel electron beam pumped rare gas VUV lamp for SPI has been developed for on-line analysis of organic trace compounds (ppb concentrations). The VUV radiation of the light source is employed for SPI in the ion source of the QMS. The concept of the interfacing of the VUV light source with the QMS is described and the SPI-QMS is characterized. On-line detection limits down to 50 ppb for benzene, toluene, and m-xylene were achieved. The instrument is well suited for continuous measurements of aromatic and aliphatic trace compounds and can therefore be used for on-line monitoring of trace compounds in dynamically fluctuating process gases. First measurements of gas standards, petrochemical samples, and on-line monitoring of automotive exhaust are presented.
- Published
- 2005
- Full Text
- View/download PDF
192. Single photon ionization (SPI) via incoherent VUV-excimer light: robust and compact time-of-flight mass spectrometer for on-line, real-time process gas analysis.
- Author
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Mühlberger F, Wieser J, Ulrich A, and Zimmermann R
- Abstract
Fast on-line detection of organic compounds from complex mixtures, such as industrial process gas streams, require selective and sensitive analytical methods. One feasible approach for this purpose is the use of mass spectrometry (MS) with a selective and soft (fragment-free) ionization technique, such as chemical ionization (CI) or photo ionization (PI). Single photon ionization (SPI) with vacuum ultraviolet (VUV) light is a particularly sof tionization technique, well-suited for detection of both aromatic and aliphatic species. Problematic, however, is the generation of the VUV light. In general, the vacuum ultraviolet (VUV) light sources for SPI-MS are based either on lasers (e.g., 118-nm radiation generated by frequency-tripling of the third harmonic of a Nd:YAG laser) or on conventional VUV lamps, such as deuterium lamps. Althoughthe laser-based techniques are very sophisticated and expensive, the conventional lamps have serious drawbacks regarding their optical parameters, such as low-output power, low spectral power density, and broad emission bands. In this work, a novel excimer VUV light source, in which an electron beam is used to form rare gas excimer species, is used. The excimer VUV light sourceproduces brilliant and intense VUV light. The novel VUV light source was coupled to a compact and mobile time-of-flight mass spectrometer (TOFMS). A special interface design, including optical (VUV optics) as well as electronic measures (e.g., pulsed ion extraction) was realized. The use of the excimer VUV lamp for SPI will allow the realization of very compact, rugged, and sensitive SPI-TOFMS devices, which preferably will be adapted for process analytical application or monitoring issues (e.g., chemical warfare detection). The excimer VUV-lamp technology delivers VUV light with a good beam quality and high-output power at low costs. Furthermore, it allows changing the emitted wavelength as well as the bandwidth of the excimer VUV lamp in t he 100-200-nm region by changing the gas filling. Consequently, SPI-TOFMS with an excimer light source is a fast detection technique that can be used for online monitoring, for example, in environmental studies or industrial manufacturing processes. In this paper, technology and characteristics of the new excimer light source, as well as the combination with the TOFMS, are presented. Furthermore, a first characterization of the SPI-TOFMS instrument, regarding analytical parameters such as detection limits and selectivity, is given. This includes a discussion of potential improvements that probably will be achievable within a future prototype genertation. Finally, first applications of the system for on-line measurement of organic trace species in a complex gas mixture (here, motorcycle exhaust gas) are presented.
- Published
- 2002
- Full Text
- View/download PDF
193. Asexual sporulation in Aspergillus nidulans.
- Author
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Adams TH, Wieser JK, and Yu JH
- Subjects
- Gene Expression Regulation, Fungal, Genes, Fungal physiology, Reproduction, Spores, Fungal genetics, Aspergillus nidulans physiology
- Abstract
The formation of mitotically derived spores, called conidia, is a common reproductive mode in filamentous fungi, particularly among the large fungal class Ascomycetes. Asexual sporulation strategies are nearly as varied as fungal species; however, the formation of conidiophores, specialized multicellular reproductive structures, by the filamentous fungus Aspergillus nidulans has emerged as the leading model for understanding the mechanisms that control fungal sporulation. Initiation of A. nidulans conidiophore formation can occur either as a programmed event in the life cycle in response to intrinsic signals or to environmental stresses such as nutrient deprivation. In either case, a development-specific set of transcription factors is activated and these control the expression of each other as well as genes required for conidiophore morphogenesis. Recent progress has identified many of the earliest-acting genes needed for initiating conidiophore development and shown that there are at least two antagonistic signaling pathways that control this process. One pathway is modulated by a heterotrimeric G protein that when activated stimulates growth and represses both asexual and sexual sporulation as well as production of the toxic secondary metabolite, sterigmatocystin. The second pathway apparently requires an extracellular signal to induce sporulation-specific events and to direct the inactivation of the first pathway, removing developmental repression. A working model is presented in which the regulatory interactions between these two pathways during the fungal life cycle determine whether cells grow or develop.
- Published
- 1998
- Full Text
- View/download PDF
194. The Neurospora rca-1 gene complements an Aspergillus flbD sporulation mutant but has no identifiable role in Neurospora sporulation.
- Author
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Shen WC, Wieser J, Adams TH, and Ebbole DJ
- Subjects
- Amino Acid Sequence, Aspergillus nidulans physiology, Base Sequence, Cloning, Molecular, DNA, Fungal, Gene Deletion, Genetic Complementation Test, Molecular Sequence Data, Mutagenesis, Neurospora crassa growth & development, Sequence Homology, Amino Acid, Spores, Fungal genetics, Aspergillus nidulans genetics, DNA-Binding Proteins genetics, Fungal Proteins genetics, Genes, Fungal, Neurospora crassa genetics, Trans-Activators genetics
- Abstract
The Aspergillus nidulans flbD gene encodes a protein with a Myb-like DNA-binding domain that is proposed to act in concert with other developmental regulators to control initiation of conidiophore development. We have identified a Neurospora crassa gene called rca-1 (regulator of conidiation in Aspergillus) based on its sequence similarity to flbD. We found that N. crassa rca-1 can complement the conidiation defect of an A. nidulans flbD mutant and that induced expression of rca-1 caused conidiation in submerged A. nidulans cultures just as was previously observed for overexpression of flbD. Thus, the N. crassa gene appears to be a functional homologue of A. nidulans flbD and this is the first demonstration of functional complementation of an A. nidulans sporulation defect using a gene from an evolutionarily distant fungus. However, deletion of the rca-1 gene in N. crassa had no major effect on growth rate, macroconidiation, microconidiation, or ascospore formation. The only phenotype displayed by the rca-1 mutant was straight or counterclockwise hyphal growth rather than the clockwise spiral growth observed for wild type. Thus, if rca-1 is involved in N. crassa development, its role is subtle or redundant.
- Published
- 1998
- Full Text
- View/download PDF
195. Dominant mutations affecting both sporulation and sterigmatocystin biosynthesis in Aspergillus nidulans.
- Author
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Wieser J, Yu JH, and Adams TH
- Subjects
- Aspergillus nidulans growth & development, Fungal Proteins genetics, Aspergillus nidulans genetics, GTP-Binding Proteins, Genes, Fungal, Mutation, Spores, Fungal, Sterigmatocystin biosynthesis, Transcription Factors
- Abstract
The initiation of conidiophore development in the filamentous fungus Aspergillus nidulans is a complex process requiring the activities of several genes including fluG, flbA, flbB, flbC, flbD, and flbE. Recessive mutations in any one of these genes result in greatly reduced expression of the brlA developmental regulatory gene and a colony morphology described as fluffy. These fluffy mutants have somewhat diverse phenotypes but generally grow as undifferentiated masses of vegetative hyphae to form large cotton-like colonies. In this paper we describe a genetic screen to identify dominant mutations resulting in similar fluffy colony morphologies. We have identified 36 dominant fluffy mutant strains and shown that 29 of these mutants have greatly reduced brlA expression as compared to wild-type. In addition, we have found that 19 of these mutants are not only developmentally altered but also fail to produce the toxic, carcinogenic, secondary metabolite sterigmatocystin. At least three of the mutants isolated result from dominant activating mutations in fadA which encodes the G alpha subunit of a heterotrimeric G-protein. Another of the mutants results from a dominant interfering mutation in brlA. We discuss the approaches taken to characterize these potentially important regulators of growth, development and secondary metabolism.
- Published
- 1997
- Full Text
- View/download PDF
196. In vivo modulated N-acyl side chain of N-acetylneuraminic acid modulates the cell contact-dependent inhibition of growth.
- Author
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Wieser JR, Heisner A, Stehling P, Oesch F, and Reutter W
- Subjects
- Cell Division drug effects, Cell Membrane drug effects, Cell Membrane physiology, Cells, Cultured, Contact Inhibition drug effects, Fibroblasts, Humans, Kinetics, Lung, Membrane Glycoproteins metabolism, N-Acetylneuraminic Acid chemical synthesis, Cell Division physiology, Contact Inhibition physiology, N-Acetylneuraminic Acid analogs & derivatives, N-Acetylneuraminic Acid pharmacology, Receptors, Cell Surface physiology
- Abstract
Sialylation of plasma membrane glycoproteins is thought to be involved in the regulation of differentiation and in the process of tumorigenesis. Here we show that sialylation also affects cell-cell contact-dependent growth regulation. When cultured in the presence of non-physiological synthetic sialic acid precursors, human diploid fibroblasts no longer exhibited density-dependent inhibition of growth. Concomitantly, increased sialylation of contactinhibin, a glycoprotein involved in density-dependent inhibition of growth, was observed. These results indicate that sialidase-resistant sialic acid modifications lead to dysregulated growth control. The modifications have been induced by N-propanoyl and other N-acyl derivatives of D-mannosamine.
- Published
- 1996
- Full Text
- View/download PDF
197. Genetic requirements for initiating asexual development in Aspergillus nidulans.
- Author
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Wieser J, Lee BN, Fondon Jw 3rd, and Adams TH
- Subjects
- Alleles, Aspergillus nidulans growth & development, Aspergillus nidulans ultrastructure, Cloning, Molecular, Epistasis, Genetic, Fungal Proteins biosynthesis, Fungal Proteins genetics, Genetic Complementation Test, Genetic Linkage, Phenotype, Promoter Regions, Genetic, Recombinant Fusion Proteins biosynthesis, Aspergillus nidulans genetics, Fungal Proteins physiology, Gene Expression Regulation, Developmental, Gene Expression Regulation, Fungal, Genes, Fungal, Reproduction, Asexual genetics, Transcription Factors
- Abstract
Conidiation in the filamentous ascomycete Aspergillus nidulans requires activation of brlA, a well-characterized transcriptional regulator of genes that are induced specifically during asexual development. We have isolated and characterized developmental mutations in six loci, designated fluG, flbA, flbB, flbC, flbD, and flbE, that result in defective development and reduced brlA expression. These mutants grow indeterminately to produce masses of aerial hyphae resulting in the formation of cotton-like colonies with a "fluffy" morphology. The results of growth and epistasis tests involving all pairwise combinations of fluffy mutations indicate complex hierarchical relationships among these loci. We discuss these genetic interactions and propose that there are multiple mechanisms for activating brlA.
- Published
- 1994
- Full Text
- View/download PDF
198. What is your diagnosis? Mineralized mass in the right caudoventral quadrant, and imperceptible serosal surfaces in the middle portion of the abdomen.
- Author
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Wieser JR
- Subjects
- Animals, Cats, Hematoma complications, Hematoma diagnostic imaging, Male, Peritoneal Diseases complications, Peritoneal Diseases diagnostic imaging, Peritoneal Diseases veterinary, Precursor Cell Lymphoblastic Leukemia-Lymphoma complications, Precursor Cell Lymphoblastic Leukemia-Lymphoma diagnostic imaging, Radiography, Cat Diseases diagnostic imaging, Hematoma veterinary, Omentum, Precursor Cell Lymphoblastic Leukemia-Lymphoma veterinary
- Published
- 1994
199. [Nursing: profession or calling? A transition from "nursing as a calling" to "nursing as a profession" is necessary and in the end it is up to us nurses to give to our profession a direction, satisfactory to ourselves].
- Author
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Wieser J
- Subjects
- Health Occupations trends, Humans, Motivation, Students, Nursing psychology
- Published
- 1992
200. Progressive muscular dystrophy (Duchenne): biochemical studies by flow-cytometry.
- Author
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Hirsch-Kauffmann M, Valet G, Wieser J, and Schweiger M
- Subjects
- Cell Cycle, Cell Survival, Cells, Cultured, Child, Child, Preschool, Female, Fibroblasts metabolism, Fibroblasts pathology, Flow Cytometry, Histocytochemistry, Humans, Hydrogen-Ion Concentration, Male, Muscular Dystrophies pathology, Esterases metabolism, Muscular Dystrophies metabolism, Receptors, Mitogen metabolism
- Abstract
The peanut lectin (PNL) receptor density of the cell membrane and several metabolic parameters of cultured fibroblasts of normal human individuals and of patients with muscular dystrophy were measured by simultaneous two and three parameter flow cytometry. The PNL-receptor density was significantly decreased on muscular dystrophy fibroblasts (between 20.7 and 33.6%) as compared to normal fibroblasts. The cell volume, the esterase activity, the intracellular pH, and the percentage of proliferating cells of both types of fibroblasts were not significantly altered. The mean cell volume of different fibroblast cultures varied between 2500 and 6000 micron 3. The concentration of the intracellular esterase activity of fibroblasts was low (0.169 relative units) as compared to lymphocytes and granulocytes of the peripheral blood (1.56 and 2.17 relative units). The fibroblasts had an acidic intracellular pH of 6.52 while lymphocytes and granulocytes had basic pH values of 7.30 and 7.17. Some of the fibroblasts were in the S + G2/M phase of the cell cycle (20%). The study shows that the measurement of biochemical parameters of vital and fixed single fibroblasts by flow-cytometry is of great interest for the recognition of differences between normal individuals and muscular dystrophy patients.
- Published
- 1985
- Full Text
- View/download PDF
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