16 research outputs found
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Design of Polymer-Embedded Heterogeneous Fenton Catalysts for the Conversion of Organic Trace Compounds
Advanced oxidation processes are the main way to remove persistent organic trace compounds from water. For these processes, heterogeneous Fenton catalysts with low iron leaching and high catalytic activity are required. Here, the preparation of such catalysts consisting of silica-supported iron oxide (Fe2O3/SiOx) embedded in thermoplastic polymers is presented. The iron oxide catalysts are prepared by a facile sol–gel procedure followed by thermal annealing (calcination). These materials are mixed in a melt compounding process with modified polypropylenes to stabilize the Fe2O3 catalytic centers and to further reduce the iron leaching. The catalytic activity of the composites is analyzed by means of the Reactive Black 5 (RB5) assay, as well as by the conversion of phenol which is used as an example of an organic trace compound. It is demonstrated that embedding of silica-supported iron oxide in modified polypropylene turns the reaction order from pseudo-first order (found for Fe2O3/SiOx catalysts), which represents a mainly homogeneous Fenton reaction, to pseudo-zeroth order in the polymer composites, indicating a mainly heterogeneous, surface-diffusion-controlled process
Does nociceptin play a role in pain disorders in man?
Nociceptin-immunoreactive cellbodies were detected in the human trigeminal ganglion, while no such fibers were identified in the temporal artery or in dermal tissue from the neck region. In four healthy subjects receiving nociceptin into the temporal muscle in an open labeled design no pain was detected. In 10 healthy subjects who received 200 pmol of nociceptin into tender non-dominant trapezius muscles in a placebo-controlled, randomized, balanced, and double-blinded design local tenderness increased (P = 0.025) while no pain was noted. Thus, the action of nociceptin should be searched for in the trigeminal ganglion and/or in the central nervous system (CNS). (C) 2002 Elsevier Science Inc. All rights reserved
Drought response of mesophyll conductance in forest understory species - impacts on water-use efficiency and interactions with leaf water movement
Regulation of stomatal (gs) and mesophyll conductance (gm) is an efficient means for optimizing the relationship between water loss and carbon uptake in plants. We assessed water-use efficiency (WUE)-based drought adaptation strategies with respect to mesophyll conductance of different functional plant groups of the forest understory. Moreover we aimed at assessing the mechanisms of and interactions between water and CO2 conductance in the mesophyll. The facts that an increase in WUE was observed only in the two species that increased gm in response to moderate drought, and that over all five species examined, changes in mesophyll conductance were significantly correlated with the drought-induced change in WUE, proves the importance of gm in optimizing resource use under water restriction. There was no clear correlation of mesophyll CO2 conductance and the tortuosity of water movement in the leaf across the five species in the control and drought treatments. This points either to different main pathways for CO2 and water in the mesophyll either to different regulation of a common pathway
Seeing, acting, understanding: motor resonance in language comprehension
Observing actions and understanding sentences about actions activates corresponding motor processes in
the observer– comprehender. In 5 experiments, the authors addressed 2 novel questions regarding
language-based motor resonance. The 1st question asks whether visual motion that is associated with an
action produces motor resonance in sentence comprehension. The 2nd question asks whether motor
resonance is modulated during sentence comprehension. The authors’ experiments provide an affirmative
response to both questions. A rotating visual stimulus affects both actual manual rotation and the
comprehension of manual rotation sentences. Motor resonance is modulated by the linguistic input and
is a rather immediate and localized phenomenon. The results are discussed in the context of theories of
action observation and mental simulation
Design of Polymer-Embedded Heterogeneous Fenton Catalysts for the Conversion of Organic Trace Compounds
Advanced oxidation processes are the main way to remove persistent organic trace compounds from water. For these processes, heterogeneous Fenton catalysts with low iron leaching and high catalytic activity are required. Here, the preparation of such catalysts consisting of silica-supported iron oxide (Fe2O3/SiOx) embedded in thermoplastic polymers is presented. The iron oxide catalysts are prepared by a facile sol–gel procedure followed by thermal annealing (calcination). These materials are mixed in a melt compounding process with modified polypropylenes to stabilize the Fe2O3 catalytic centers and to further reduce the iron leaching. The catalytic activity of the composites is analyzed by means of the Reactive Black 5 (RB5) assay, as well as by the conversion of phenol which is used as an example of an organic trace compound. It is demonstrated that embedding of silica-supported iron oxide in modified polypropylene turns the reaction order from pseudo-first order (found for Fe2O3/SiOx catalysts), which represents a mainly homogeneous Fenton reaction, to pseudo-zeroth order in the polymer composites, indicating a mainly heterogeneous, surface-diffusion-controlled process
A New Light-Emitting, Fabric-Based Device for Photodynamic Therapy of Actinic Keratosis: Protocol for a Randomized, Controlled, Multicenter, Intra-Individual, Phase II Noninferiority Study (The Phosistos Study)
International audienceBackground: Actinic keratosis (AK) is a common early in situ skin carcinoma caused by long-term sun exposure and usually develops on sun-exposed skin areas. Left untreated, AK may progress to squamous cell carcinoma. To prevent such risk, most clinicians routinely treat AK. Therapy options for AK include cryotherapy, topical treatments, curettage, excision surgery, and photodynamic therapy (PDT).Objective: The aim of this study is to assess the noninferiority, in terms of efficacy at 3 months, of a PDT protocol involving a new light-emitting device (PDT using the Phosistos protocol [P-PDT]) compared with the conventional protocol (PDT using the conventional protocol [C-PDT]) in the treatment of AK.Methods: In this randomized, controlled, multicenter, intra-individual, phase II noninferiority clinical study, subjects with AK of the forehead and scalp are treated with P-PDT on one area and with C-PDT on the contralateral area. In both areas, lesions are prepared and methyl aminolevulinate (MAL) is applied. Thirty minutes after MAL application, the P-PDT area is exposed to red light at low irradiance (1.3 mW/cm2) for 2.5 hours so that a light dose of 12 J/cm2 is achieved. In the control area (C-PDT area), a 37 J/cm2 red light irradiation is performed 3 hours after MAL application. Recurrent AK at 3 months is retreated. The primary end point is the lesion complete response rate at 3 months. Secondary end points include pain scores at 1 day, local tolerance at 7 days, lesion complete response rate at 6 months, cosmetic outcome at 3 and 6 months, and patient-reported quality of life and satisfaction throughout the study. A total of 45 patients needs to be recruited.Results: Clinical investigations are complete: 46 patients were treated with P-PDT on one area (n=285 AK) and with C-PDT on the contralateral area (n=285 AK). Data analysis is ongoing, and statistical results will be available in the first half of 2019.Conclusions: In case of noninferiority in efficacy and superiority in tolerability of P-PDT compared with C-PDT, P-PDT could become the treatment of choice for AK.Trial registration: ClinicalTrials.gov NCT03076892; https://clinicaltrials.gov/ct2/show/NCT03076892 (Archived by WebCite at http://www.webcitation.org/779qqVKek).International registered report identifier (irrid): DERR1-10.2196/12990
Institutionelle Transformationsprozesse der Schulkultur in ostdeutschen Gymnasien Zur Rekonstruktion gymnasialer Schulmythen und Partizipationsverhaeltnisse
Nach der Wende hat sich in den neu entstandenen Gymnasien in der ehemaligen DDR eine 'Diversifikation' schulischer Kulturen ergeben. Die Studie unterstellt damit nicht, dass es in der DDR eine einheitliche und gleichfoermige Schullandschaft gegeben hat. Es existierte jedoch eine unterschwellige und inoffizielle Differenziertheit des DDR-Schulsystems und dessen 'untergruendigen Schulmythen', die erst jetzt offiziell freigesetzt werden koennen. Die Studie versucht die Rekonstruktion dieser Schulkultur durch die Erschliessung des spannungsvollen Verhaeltnisses zwischen dem Realen, dem Symbolischen und dem einzelnen Imaginaeren der Schule in den neuen Bundeslaendern. Die Schulkultur wird dabei insgesamt als das Ergebnis der Auseinandersetzungen und Aushandlungen der schulischen Akteure im Rahmen kultureller Distinktionen verstanden. (pre)Available from UuStB Koeln(38)-990106303 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman