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5. Adaptive deep brain stimulation of the superolateral medial forebrain bundle

Author

Rickert, J., Schüttler, M., Coenen, V.A., Schläpfer, T.E., Tangermann, M.W., Rickert, J., Schüttler, M., Coenen, V.A., Schläpfer, T.E., and Tangermann, M.W.

Abstract

24 februari 2022, Item does not contain fulltext, A system for brain stimulation of a patient is provided, the system having an implantable stimulator, at least one sensor component for acquiring at least one measure indicative of patient's mood, and at least one implantable stimulation electrode, designed for providing electrical pulses stimulating inside the patient's brain. The at least one stimulation electrode is connectable, through an implantable connector, to the implantable stimulator, the implantable stimulator having at least one programmable channel for conducting the electrical stimulation pulses to the at least one stimulation electrode, and being adapted for receiving continuous input signals from the at the least one sensor component. The system also has a computational unit for processing the at least one measure, and a patient's body external control interface (5) for patient and/or physician interactions.

Published
2022

10. Integration of product entropy and LCA to screen the potential environmental impacts of complex product systems at the end-of-life stage

Author

Rickert, J., Drachenfels, N. von, Cerdas, F., Herrmann, C., and Publica

Subjects
recycling, environment, lifecycle
Abstract

Applying life cycle assessment (LCA) early in the development of technologies is essential to anticipate potential unforeseen environmental consequences. Modelling the lifecycle of a complex product is nevertheless challenging, as the data required is usually scarce. The approach presented in this paper integrates product entropy into end-of-life modelling for LCA. This enables anticipating the fate of a product after its end-of-use leading to a more realistic allocation of environmental impacts. The approach is demonstrated for the case study of recycling traction batteries with emerging traction battery cell chemistries.

Published
2019

16. About the influence of long-term retarders on the basis of phosphonic acid on the hydration of several clinker phases, portland cement clinkers and portland cements

Author

Rickert, J��rg

Subjects
620 Ingenieurwissenschaften und zugeordnete T��tigkeiten
Abstract

Neben dem Schwerpunkt der Verfl��ssigung werden auch Zusatzmittel ben��tigt, die extrem lange Verarbeitbarkeitszeiten des Betons erm��glichen. Eine neue Wirkungsgruppe, durch die Verarbeitbarkeitszeiten von ��ber 90 Stunden er-reicht werden k��nnen, sind Langzeitverz��gerer (LVZ) auf der Basis von Phosphons��ure. In systematischen Versuchen wurden grundlegende Erkenntnisse ��ber die Wirkungsmechanismen von LVZ auf die Hydratation gewonnen. Es hat sich gezeigt, dass die verz��gernde Wirkung von LVZ auf die Bildung von schwer l��slichem Calciumphosphonat zur��ckzuf��hren ist, welches die Partikeloberfl��chen ��abdichtet��. Vom Angebot an gel��stem Calcium h��ngt es ab, ob sich das ��abdichtende�� Calciumphosphonat direkt bildet oder ob durch den Calciumanspruch des LVZ eine kurzzeitig verst��rkte Hydratation reaktiver Klin-kerphasen hervorgerufen wird. Sulfatoptimierte Zemente wiesen aufgrund der Anteile an Sulfattr��ger gen��ge! nd Calcium-Ionen f��r eine sofortige Bildung von Calciumphosphonat auf. In Verbindung mit der Bildung von prim��rem Ettringit bildet die Sulfattr��geroptimierung die Grundlage f��r die erw��nschte Wirkungsweise des Zusatzmittels., In addition to the large group of plasticizing admixtures, such kind of admixtures are required which enable a very long time of workability of concrete. The workability of concrete over a period of more than 90 hours can be achieved by long-term retarders. This new type of admixture is based on phosphonic acid. By systematic investigations profound knowledge about the operative mechanisms of long-term retarders could be drawn. The retarding action is due to a formation of sparingly soluble calcium phosphonate which ��seal up�� the particle surface. Whether the addition of long-term retarder leads to an immediate formation of calcium phosphonate or to a short termed acceleration of the hydration of reactive clinker phases depends on the supply of solved calcium. Because of the adjusted calcium sulphate content in cement the concentration of calcium is high enough for an immediate formation of sparingly soluble calcium! phosphonate. In combination with the formation of primary ettringite the calcium sulphate agent is the basis for the desired mode of action of the long-term retarder.

Published
2004
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29. Influences of temperature on interactions between superplasticizers and cements with several main constituents.

Author

Herrmann, J. and Rickert, J.

Subjects
*TEMPERATURE effect, *PLASTICIZERS, *ATMOSPHERIC temperature, *PORTLAND cement, *CEMENT clinkers, *X-ray diffraction measurement
Abstract

The effect of superplasticizers at standard temperature is well known. Influences of common hot and cold weather temperatures on interactions between superplasticizers and cements were determined. With temperature decreasing from 30 to 5 °C the superplasticizer saturation dosage for Portland cement decreased considerably. Without any adjustment, fluctuations in temperature can quickly result in an insufficient or excessive addition of superplasticizer. The use of clinker-efficient cements with higher proportions of further main constituents enhanced the robustness of the cement-superplasticizer-interactions against temperature variations. Cements with several main constituents compensated for the temperature-dependent action mechanisms of the superplasticizers to a more uniform performance at varying temperatures, [ABSTRACT FROM AUTHOR]

Published
2018

39. Zeta potential and rheology of cement pastes - influence of superplasticizers and of granulated blastfurnace slag and limestone.

Author

Rickert, J.

Subjects
*MINERAL aggregates, *SLAG, *STRENGTH of building materials, *ADSORPTION (Chemistry), *LIMESTONE
Abstract

The influence of four PCE-based superplasticizers (synthesized selectively in the laboratory) on the shear resistance, especially at the saturation point, of cement pastes was investigated at the FIZ (Research Institute of the Cement Industry) using two commercially available cements. The intention was to clarify whether, and possibly from which parameters of the molecular structure of the PCE (polycarboxylate ether), it is possible to deduce a general mode of operation in conjunction with different cements. Rheological investigations of the shear resistance, especially at the saturation point, were compared with zeta potential measurements. The influence of two limestones and two granulated blastfurnace slags on the zeta potential and the shear resistance of laboratory cements produced with them, as well as on the adsorption of a commercially available PCE, was also examined. For the cements investigated the PCEs with high charge densities were relatively independent of the lengths of the side and main chains with respect to reaching the saturation point most effectively. The duration of the plasticizing action on the saturation point did not always correlate with the lengths of the side chains. The shear resistance fell with increasing quantity of active substance and the zeta potential was displaced in the direction of the isoelectric point (0 mV) due to the displacement of the shear plane caused by adsorption of the PCE. There was a correlation between the quantity of active substance adsorbed, the zeta potential and the shear resistance. The saturation point was determined both with the aid of rheological measurements of the shear resistance and by determining the zeta potential. The limestones and granulated blastfurnace slags investigated were able to adsorb sulfate ions from the pore solution, resulting in a negative zeta potential. Competitive adsorption between sulfate ions and plasticizer molecules is therefore also to be expected with these components. Increasing the proportion of granulated blastfurnace slag led to a significant drop in the shear resistance of the cement pastes and displacement of the zeta potential in the direction of the isoelectric point. The limestones used affected the shear resistance and the zeta potential of the cement paste to different extents and more significantly than the granulated blastfurnace slags investigated. [ABSTRACT FROM AUTHOR]

Published
2012

40. Dolomite-rich carbonate rocks as cement main constituent.

Author

Lipus, K., Dietrich, N., and Rickert, J.

Subjects
*CARBONATE rocks, *DOLOMITE, *LIMESTONE, *CEMENT, *PORTLAND cement, *CONCRETE durability, *ROCK concerts
Abstract

The suitability of dolomite-rich carbonate rocks as a cement main constituent and thus for the production of highperformance cements and concretes of high durability was investigated. Four Portland cements were combined with five carbonate rocks containing different dolomites and a calcite-rich limestone as reference material, to investigate a total of thirty CEM ll/A cements with 20 mass % and CEM ll/B with 30 mass % of the carbonate constituent. The dolomite content of the carbonate rocks was between 67 and 98 mass %. Fresh and hardened concrete properties were tested. The focus was on studies on frost resistance. It turned out that all tested dolomite-rich carbonate rocks have shown a comparable high-performance with the calcite-rich reference limestone. Differences of Portland cement (clinker) properties had a greater impact on the cement and concrete performance than the differences between the five dolomite containing carbonate rocks. Based on the results of the investigation, dolomite-rich carbonate rocks could also be used as a cement main constituent as well as limestones defined in the current cement standard. A corresponding change in the cement standard would enable cement producers to use also dolomitic limestone resources in their quarries in future. [ABSTRACT FROM AUTHOR]

Published
2019

41. Influence of limestone composition in cement on cement and concrete properties.

Author

Dietrich, N., Lipus, K., and Rickert, J.

Subjects
*LIMESTONE, *PORTLAND cement, *PORTLAND cement industry, *CALCIUM carbonate, *CEMENT industries & the environment, *MATERIALS compression testing, ENVIRONMENTAL aspects
Abstract

Using numerous limestones, the impact of limestone specific parameters on the properties of the derived Portland limestone cements (CEM II/A- and CEM II/B-cements with 15 or 30 mass % of limestone) and the durability of concretes made of these cements, has been investigated. Parameters were the geologic origin, microstructural characteristics and the mineralogical composition, especially the secondary phases beside calcite. The limestone samples basically differed in the calcium carbonate content. All limestones met the standard requirements acc. to EN 197-1 for TOC content and methylene blue adsorption, but not always for the calcium carbonate content. The different calcium carbonate contents of the limestones had no significant impact on the microstructure, porosity and compressive strength development of the Portland limestone cement mortars investigated. However, parameters like particle size of the cement component and the limestone content were of great importance. However, differences in the mineral phases and their distribution in the limestone microstructure influenced certain durability properties of the concretes made with CEM ll/B cements containing limestone. Non-standard compliant limestones with high dolomite content resulted in consistently good concrete durability, and those with low quartz to clay mass ratio in mostly appropriate concrete durability. [ABSTRACT FROM AUTHOR]

Published
2017

43. On Patient Safety: The Danger of Private Equity Involvement in Healthcare.

Author

Rickert J

Subjects
Humans, Private Sector, Healthcare Disparities, Health Equity, Patient Safety
Abstract

Competing Interests: The author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research ® editors and board members are on file with the publication and can be viewed on request.

Published
2024
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44. On Patient Safety: Managing the Spread of Tropical Diseases.

Author

Rickert J

Subjects
Humans, Tropical Medicine
Abstract

Competing Interests: The author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research ® editors and board members are on file with the publication and can be viewed on request.

Published
2024
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45. Moderate Intensity Exercise Reduces Side Effects of Cancer Therapy and Maintains Cardiorespiratory Fitness in Male Breast Cancer Patients: Findings from the BRECA Male Crossover Study.

Author

Schultz EB, Zubac D, Bloch W, Baurecht H, Rickert J, and Baumann FT

Abstract

Introduction: There is growing evidence that aerobic exercise mitigates cancer therapy-related side effects and improves cardiorespiratory fitness (CRF). However, to the best of our knowledge, no exercise study has been conducted in male breast cancer (MBC) patients. The aim of this study was to investigate the feasibility and efficacy of different exercise intensities on CRF and self-reported questionnaire items in MBC patients., Methods: Twenty-two MBC patients (60 ± 9 years) participated in this randomized crossover study. After completion of medical treatment, MBC patients were randomly assigned to either moderate (40-50% of heart rate [HR] max. and self-perceived exertion: 11) or vigorous (70-80% of HR max. and self-perceived exertion: 15) exercise intensity during the first 3 months of the study. After a 1-month washout period, participants switched group assignments. Primary endpoints were CRF and questionnaire items., Results: We observed a dropout rate of 36% over 7 months, with the number of participants decreasing from 22 to 14. The results showed significant improvements in "Physical Function" ( p = 0.037) and "Social Function" ( p = 0.016) after moderate training. A non-significant improvement was also observed in "Breast Symptoms" ( p = 0.095), but there was no change in "Fatigue" ( p = 0.306). There were no differences observed in cardiovascular fitness (V̇O 2 peak) between the treatment groups., Conclusion: This study emphasizes the effectiveness of exercise intervention for an exceedingly rare cancer, highlighting the vital role of moderate intensity aerobic exercise in mitigating treatment side effects. Despite minimal peak V̇O 2 differences, both exercise protocols adequately sustain CRF. Future studies are imperative to design optimized, sex-specific rehabilitation strategies tailored to the unique requirements of MBC patients, advancing our understanding of this under explored realm., Competing Interests: The authors have no conflicts of interest to declare., (© 2023 The Author(s). Published by S. Karger AG, Basel.)

Published
2023
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46. On Patient Safety: When Doctors Strike.

Author

Rickert J

Subjects
Humans, Medical Staff, Hospital, Strikes, Employee, Physicians
Abstract

Competing Interests: The author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research ® editors and board members are on file with the publication and can be viewed on request.

Published
2023
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47. On Patient Safety: Latent Tuberculosis-How We Can Help Address This Problem.

Author

Rickert J

Subjects
Humans, Rifampin, Risk Factors, Latent Tuberculosis diagnosis
Abstract

Competing Interests: The author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research ® editors and board members are on file with the publication and can be viewed on request.

Published
2023
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48. On Patient Safety: Quit Skipping Your Checklist-Based Time-Outs.

Author

Rickert J

Subjects
Humans, Operating Rooms, Checklist, Patient Safety
Abstract

Competing Interests: The author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research ® editors and board members are on file with the publication and can be viewed on request.

Published
2023
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49. On Patient Safety: Combating Antibiotic Resistance With Effective Hand Hygiene.

Author

Rickert J

Subjects
Humans, Drug Resistance, Microbial, Hand Disinfection, Guideline Adherence, Patient Safety, Infection Control, Hand Hygiene, Cross Infection
Abstract

Competing Interests: The author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request.

Published
2023
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50. Toward a fully implantable ecosystem for adaptive neuromodulation in humans: Preliminary experience with the CorTec BrainInterchange device in a canine model.

Author

Schalk G, Worrell S, Mivalt F, Belsten A, Kim I, Morris JM, Hermes D, Klassen BT, Staff NP, Messina S, Kaufmann T, Rickert J, Brunner P, Worrell GA, and Miller KJ

Abstract

This article describes initial work toward an ecosystem for adaptive neuromodulation in humans by documenting the experience of implanting CorTec's BrainInterchange (BIC) device in a beagle canine and using the BCI2000 environment to interact with the BIC device. It begins with laying out the substantial opportunity presented by a useful, easy-to-use, and widely available hardware/software ecosystem in the current landscape of the field of adaptive neuromodulation, and then describes experience with implantation, software integration, and post-surgical validation of recording of brain signals and implant parameters. Initial experience suggests that the hardware capabilities of the BIC device are fully supported by BCI2000, and that the BIC/BCI2000 device can record and process brain signals during free behavior. With further development and validation, the BIC/BCI2000 ecosystem could become an important tool for research into new adaptive neuromodulation protocols in humans., Competing Interests: GW declares intellectual property disclosures related to behavioral state and seizure classification algorithms licensed to Cadence Neuroscience Inc. GW has licensed intellectual property to NeuroOne, Inc. GS has provided consulting services to CorTec and JR is employed by CorTec. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Schalk, Worrell, Mivalt, Belsten, Kim, Morris, Hermes, Klassen, Staff, Messina, Kaufmann, Rickert, Brunner, Worrell and Miller.)

Published
2022
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