39 results on '"Markus Brand"'
Search Results
2. Positive resection margins in Crohn’s disease are a relevant risk factor for postoperative disease recurrence
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Matthias Kelm, Clara Benatzky, Viktoria Buck, Anna Widder, Katrin Schoettker, Mathias Rosenfeldt, Markus Brand, Nicolas Schlegel, Christoph-Thomas Germer, Alexander Meining, Asma Nusrat, and Sven Flemming
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Crohn’s disease ,Postoperative disease recurrence ,Ileocecal resection ,Medicine ,Science - Abstract
Abstract Postoperative disease recurrence in Crohn’s disease represents a relevant issue despite recent advancements in surgical and medical therapies. Additional criteria are necessary to improve the identification of patients at risk and to enable selective therapeutic approaches. The role of resection margins on disease recurrence remains unclear and general recommendations are lacking. A single-center retrospective analysis was performed including all patients who received ileocecal resection due to Crohn’s disease. Resection margins were analyzed by two independent pathologists and defined by histopathological criteria based on previous consensus reports. 158 patients were included for analysis with a median follow up of 35 months. While postoperative morbidity was not affected, positive resection margins resulted in significantly increased rates of severe endoscopic recurrence at 6 months (2.0% versus 15.6%, p = 0.02) and overall (4.2% versus 19.6%, p = 0.001), which resulted in significantly increased numbers of surgical recurrence (0% versus 4.5%, p = 0.04). Additionally, positive margins were identified as independent risk factor for severe endoscopic disease recurrence in a multivariate analysis. Based on that, positive margins represent an independent risk factor for postoperative endoscopic and surgical disease recurrence. Prospective studies are required to determine whether extended resection or postoperative medical prophylaxis is beneficial for patients with positive resection margins.
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- 2024
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3. Kelp forest community structure and demography in Kongsfjorden (Svalbard) across 25 years of Arctic warming
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Luisa Düsedau, Stein Fredriksen, Markus Brand, Philipp Fischer, Ulf Karsten, Kai Bischof, Amanda Savoie, and Inka Bartsch
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age structure ,biomass ,coastal darkening ,depth zonation ,macroalgae ,time series ,Ecology ,QH540-549.5 - Abstract
Abstract The Arctic archipelago of Svalbard is a hotspot of global warming and many fjords experience a continuous increase in seawater temperature and glacial melt while sea‐ice cover declines. In 1996/1998, 2012–2014, and 2021 macroalgal biomass and species diversity were quantified at the study site Hansneset, Kongsfjorden (W‐Spitsbergen) in order to identify potential changes over time. In 2021, we repeated the earlier studies by stratified random sampling (1 × 1 m2, n = 3) along a sublittoral depth transect (0, 2.5, 5, 10, and 15 m) and investigated the lower depth limits of dominant brown algae between 3 and 19 m. The maximum fresh weight (FW) of all seaweeds was 11.5 kg m−2 at 2.5 m and to 99.9% constituted of kelp. Although biomass distribution along the depth transect in 2021 was not significantly different compared to 2012/2013, the digitate kelp community (Laminaria digitata/Hedophyllum nigripes) had transformed into an Alaria esculenta‐dominated kelp forest. Consequently, a pronounced shift in kelp forest structure occurred over time as we demonstrate that biomass allocation to thallus parts is kelp species‐specific. Over the past decade, kelp demography changed and in 2021 a balanced age structure of kelps (juveniles plus many older kelp individuals) was only apparent at 2.5 m. In addition, the abundances and lower depth limits of all dominant brown algae declined noticeably over the last 25 years while the red algal flora abundance remained unchanged at depth. We propose that the major factor driving the observed changes in the macroalgal community are alterations in underwater light climate, as in situ data showed increasing turbidity and decreasing irradiance since 2012 and 2017, respectively. As a consequence, the interplay between kelp forest retreat to lower depth levels caused by coastal darkening and potential macroalgal biomass gain with increasing temperatures will possibly intensify in the future with unforeseen consequences for melting Arctic coasts and fjord ecosystem services.
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- 2024
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4. The Role of Specialized Instruments for Advanced Endoscopic Resections in Gastrointestinal Disease
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Markus Brand, Karl-Hermann Fuchs, Joel Troya, Alexander Hann, and Alexander Meining
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interventional endoscopy ,therapeutic endoscopy ,endoscopic graspers ,ESD ,GI endoscopy ,Science - Abstract
Introduction: Advanced endoscopic therapy techniques have been developed and have created alternative treatment options to surgical therapy for several gastrointestinal diseases. This work will focus on new endoscopic tools for special indications of advanced endoscopic resections (ER), especially endoscopic submucosal dissection (ESD), which were developed in our institution. This paper aims to analyze these specialized instruments and identify their status. Methods: Initially, the technical process of ESD was analyzed, and the following limitations of the different endoscopic steps and the necessary manipulations were determined: the problem of traction–countertraction, the grasping force needed to pull on tissue, the instrument tip maneuverability, the limited angulation/triangulation, and the mobility of the scope and instruments. Five instruments developed by our team were used: the Endo-dissector, additional working channel system, external independent next-to-the-scope grasper, 3D overtube working station, and over-the-scope grasper. The instruments were used and applied according to their special functions in dry lab, experimental in vivo, and clinical conditions by the members of our team. Results: The Endo-dissector has a two-fold function: (1) grasping submucosal tissue with enough precision and strength to pull it off the surrounding mucosa and muscle, avoiding damage during energy application and (2) effectively dividing tissue using monopolar energy. The AWC system quickly fulfills the lack of a second working channel as needed to complete the endoscopic task on demand. The EINTS grasper can deliver a serious grasping force, which may be necessary for a traction–countertraction situation during endoscopic resection for lifting a larger specimen. The 3D overtube multifunctional platform provides surgical-like work with bimanual-operated instruments at the tip of the scope, which allows for a coordinated approach during lesion treatment. The OTSG is a grasping tool with very special features for cleaning cavities with debris. Conclusions: The research and development of instruments with special features can solve unmet needs in advanced endoscopic procedures. The latter may help to increase indications for the endoscopic resections of gut lesions in the future.
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- 2023
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5. Operating Cabled Underwater Observatories in Rough Shelf-Sea Environments: A Technological Challenge
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Philipp Fischer, Holger Brix, Burkard Baschek, Alexandra Kraberg, Markus Brand, Boris Cisewski, Rolf Riethmüller, Gisbert Breitbach, Klas Ove Möller, Jean-Pierre Gattuso, Samir Alliouane, Willem H. van de Poll, and Rob Witbaard
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coastal cabled observatories ,remote sensor operation ,data quality ,Arctic coasts ,North Sea ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
Cabled coastal observatories are often seen as future-oriented marine technology that enables science to conduct observational and experimental studies under water year-round, independent of physical accessibility to the target area. Additionally, the availability of (unrestricted) electricity and an Internet connection under water allows the operation of complex experimental setups and sensor systems for longer periods of time, thus creating a kind of laboratory beneath the water. After successful operation for several decades in the terrestrial and atmospheric research field, remote controlled observatory technology finally also enables marine scientists to take advantage of the rapidly developing communication technology. The continuous operation of two cabled observatories in the southern North Sea and off the Svalbard coast since 2012 shows that even highly complex sensor systems, such as stereo-optical cameras, video plankton recorders or systems for measuring the marine carbonate system, can be successfully operated remotely year-round facilitating continuous scientific access to areas that are difficult to reach, such as the polar seas or the North Sea. Experience also shows, however, that the challenges of operating a cabled coastal observatory go far beyond the provision of electricity and network connection under water. In this manuscript, the essential developmental stages of the “COSYNA Shallow Water Underwater Node” system are presented, and the difficulties and solutions that have arisen in the course of operation since 2012 are addressed with regard to technical, organizational and scientific aspects.
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- 2020
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6. Evolution of endoscopic vacuum therapy for upper gastrointestinal leakage over a 10-year period: a quality improvement study
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Stanislaus, Reimer, Florian, Seyfried, Sven, Flemming, Markus, Brand, Alexander, Weich, Anna, Widder, Lars, Plaßmeier, Peter, Kraus, Anna, Döring, Ilona, Hering, Mohammed K, Hankir, Alexander, Meining, Christoph-Thomas, Germer, Johan F, Lock, and Kaja, Groneberg
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Upper Gastrointestinal Tract ,Humans ,Anastomotic Leak ,Surgery ,Quality Improvement ,Negative-Pressure Wound Therapy ,Endoscopy, Gastrointestinal - Abstract
Background Endoscopic vacuum therapy (EVT) is an effective treatment option for leakage of the upper gastrointestinal (UGI) tract. The aim of this study was to evaluate the clinical impact of quality improvements in EVT management on patients’ outcome. Methods All patients treated by EVT at our center during 2012–2021 were divided into two consecutive and equal-sized cohorts (period 1 vs. period 2). Over time several quality improvement strategies were implemented including the earlier diagnosis and EVT treatment and technical optimization of endoscopy. The primary endpoint was defined as the composite score MTL30 (mortality, transfer, length-of-stay > 30 days). Secondary endpoints included EVT efficacy, complications, in-hospital mortality, length-of-stay (LOS) and nutrition status at discharge. Results A total of 156 patients were analyzed. During the latter period the primary endpoint MTL30 decreased from 60.8 to 39.0% (P = .006). EVT efficacy increased from 80 to 91% (P = .049). Further, the need for additional procedures for leakage management decreased from 49.9 to 29.9% (P = .013) and reoperations became less frequent (38.0% vs.15.6%; P = .001). The duration of leakage therapy and LOS were shortened from 25 to 14 days (P = .003) and 38 days to 25 days (P = .006), respectively. Morbidity (as determined by the comprehensive complication index) decreased from 54.6 to 46.5 (P = .034). More patients could be discharged on oral nutrition (70.9% vs. 84.4%, P = .043). Conclusions Our experience confirms the efficacy of EVT for the successful management of UGI leakage. Our quality improvement analysis demonstrates significant changes in EVT management resulting in accelerated recovery, fewer complications and improved functional outcome.
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- 2022
7. A video based benchmark data set (ENDOTEST) to evaluate computer-aided polyp detection systems
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Daniel Fitting, Adrian Krenzer, Joel Troya, Michael Banck, Boban Sudarevic, Markus Brand, Wolfgang Böck, Wolfram G. Zoller, Thomas Rösch, Frank Puppe, Alexander Meining, and Alexander Hann
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Benchmarking ,Gastroenterology ,Humans ,Colonic Polyps ,Mass Screening ,Colonoscopy - Abstract
Computer-aided polyp detection (CADe) may become a standard for polyp detection during colonoscopy. Several systems are already commercially available. We report on a video-based benchmark technique for the first preclinical assessment of such systems before comparative randomized trials are to be undertaken. Additionally, we compare a commercially available CADe system with our newly developed one.ENDOTEST consisted in the combination of two datasets. The validation dataset contained 48 video-snippets with 22,856 manually annotated images of which 53.2% contained polyps. The performance dataset contained 10 full-length screening colonoscopies with 230,898 manually annotated images of which 15.8% contained a polyp. Assessment parameters were accuracy for polyp detection and time delay to first polyp detection after polyp appearance (FDT). Two CADe systems were assessed: a commercial CADe system (GI-Genius, Medtronic), and a self-developed new system (ENDOMIND). The latter being a convolutional neuronal network trained on 194,983 manually labeled images extracted from colonoscopy videos recorded in mainly six different gastroenterologic practices.On the ENDOTEST, both CADe systems detected all polyps in at least one image. The per-frame sensitivity and specificity in full colonoscopies was 48.1% and 93.7%, respectively for GI-Genius; and 54% and 92.7%, respectively for ENDOMIND. Median FDT of ENDOMIND with 217 ms (Inter-Quartile Range(IQR)8-1533) was significantly faster than GI-Genius with 1050 ms (IQR 358-2767,Our benchmark ENDOTEST may be helpful for preclinical testing of new CADe devices. There seems to be a correlation between a shorter FDT with a higher sensitivity and a lower specificity for polyp detection.
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- 2022
8. Artificial intelligence based polyp size measurement in gastrointestinal endoscopy using the auxiliary water jet as a reference
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Boban Sudarevic, Philipp Sodmann, Ioannis Kafetzis, Joel Troya, Thomas Joachim Lux, Zita Sassmannshausen, Katja Herold, Markus Brand, Katrin Schöttker, Stefan Andreas Schmidt, Wolfram G. Zoller, Alexander Meining, and Alexander Hann
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Gastroenterology - Abstract
Background and study aims Measurement of colorectal polyp size during endoscopy is mainly performed visually. In this work, we propose a novel polyp size measurement system (Poseidon) based on artificial intelligence (AI) using the auxiliary water jet as a measurement reference. Methods Visual estimation, biopsy forceps-based estimation, and Poseidon were compared using a CT-colonography-based silicone model with 28 polyps of defined sizes. Four experienced gastroenterologists estimated polyp sizes visually and with biopsy forceps. Furthermore, the gastroenterologists recorded images of each polyp with the water jet in proximity for the application of Poseidon. Additionally, Poseidon's measurements of 29 colorectal polyps during clinical routine were compared to visual estimates. Results Visual estimation had the largest median percentage error (PE) of 25.2% (95% confidence interval (CI95%): 19.1, 30.4), followed by biopsy forceps-based estimation with median 20% (14.4, 25.6) in the silicone model. Poseidon presented a significantly lower median PE of 7.4% (5, 9.4; p
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- 2023
9. Age class composition and growth of Atlantic cod (Gadus morhua) in the shallow water zone of Kongsfjorden, Svalbard
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Markus Brand, Lisa Spotowitz, Felix Christopher Mark, Jørgen Berge, Erlend Lindau Langhelle, Jan Marcin Węsławski, Jane Aanestad Godiksen, and Philipp Fischer
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General Agricultural and Biological Sciences - Abstract
Although Atlantic cod has been observed in Svalbard waters since the 1880s, knowledge about the presence in the Arctic shallow water zone is limited. The regular catch of juvenile Atlantic cod in Kongsfjorden since 2008 is in line with an overall northward shift of boreal fish species toward the Arctic. This is the first study showing the age class composition, growth rates, and stomach content of Atlantic cod in the shallow water zone of Kongsfjorden, Svalbard. From 2012 to 2014 a total of 721 specimens were sampled in 3 to 12 m water depth. The primary age classes were identified as 0+, 1+, and 2+ using otolith age analysis. The different cohorts of these specimens show stable growth rates during the polar day and night. By stomach content analysis, we show that these specimens primarily feed on benthic food sources. These observations support the assumption that the shallow water zone of Kongsfjorden is likely to be a nursery ground for Atlantic cod.
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- 2022
10. Over-the-scope-grasper: A new tool for pancreatic necrosectomy and beyond - first multicenter experience
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Markus Brand, Jeannine Bachmann, Christoph Schlag, Ulrich Huegle, Imdadur Rahman, Edris Wedi, Benjamin Walter, Oliver Möschler, Lukas Sturm, Alexander Meining, and University of Zurich
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10219 Clinic for Gastroenterology and Hepatology ,610 Medicine & health - Abstract
Endoscopic treatment of pancreatic necrosis can be challenging and time-consuming because sticky necrotic debris is sometimes difficult to remove. The over-the-scope-grasper, a new tool that has recently become available for this purpose, might also be useful for other indications. However, clinical data on the efficacy and safety of this new device are lacking.To evaluate the technical success and safety of the device in a multicenter setting.The over-the-scope-grasper was used in nine selected endoscopic centers between November 2020 and October 2021 for appropriate indications. Overall, 56 procedures were included in the study. We retrospectively evaluated procedural parameters of all endoscopic interventions using a predefined questionnaire, with special respect to technical success, indications, duration of intervention, type of sedation, and complications. In the case of pancreatic necrosectomy, the access route, stent type, number of necrosis pieces removed, and clinical handling were also recorded.A total of 56 procedures were performed, with an overall technical success rate of 98%. Most of the procedures were endoscopic pancreatic necrosectomies (33 transgastric, 4 transduodenal). In 70% of the procedures, access to the necrotic cavity was established with a lumen apposing metal stent. The technical success of pancreatic necrosectomy was 97%, with a mean of 8 pieces (range, 2-25 pieces) of necrosis removed in a mean procedure time of 59 min (range, 15-120 min). In addition, the device has been used to remove blood clots (These first multicenter data demonstrate that the over-the-scope-grasper is a promising device for endoscopic pancreatic necrosectomy, which is also appropriate for removing foreign bodies and blood clots, or cleaning insufficiency cavities prior to endoluminal vacuum therapy.
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- 2022
11. Development and evaluation of a deep learning model to improve the usability of polyp detection systems during interventions
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Markus Brand, Joel Troya, Adrian Krenzer, Zita Saßmannshausen, Wolfram G. Zoller, Alexander Meining, Thomas J. Lux, and Alexander Hann
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Deep Learning ,Oncology ,Artificial Intelligence ,Gastroenterology ,Colonic Polyps ,Humans ,Colonoscopy ,ddc:610 ,Sensitivity and Specificity - Abstract
Background The efficiency of artificial intelligence as computer-aided detection (CADe) systems for colorectal polyps has been demonstrated in several randomized trials. However, CADe systems generate many distracting detections, especially during interventions such as polypectomies. Those distracting CADe detections are often induced by the introduction of snares or biopsy forceps as the systems have not been trained for such situations. In addition, there are a significant number of non-false but not relevant detections, since the polyp has already been previously detected. All these detections have the potential to disturb the examiner's work. Objectives Development and evaluation of a convolutional neuronal network that recognizes instruments in the endoscopic image, suppresses distracting CADe detections, and reliably detects endoscopic interventions. Methods A total of 580 different examination videos from 9 different centers using 4 different processor types were screened for instruments and represented the training dataset (519,856 images in total, 144,217 contained a visible instrument). The test dataset included 10 full-colonoscopy videos that were analyzed for the recognition of visible instruments and detections by a commercially available CADe system (GI Genius, Medtronic). Results The test dataset contained 153,623 images, 8.84% of those presented visible instruments (12 interventions, 19 instruments used). The convolutional neuronal network reached an overall accuracy in the detection of visible instruments of 98.59%. Sensitivity and specificity were 98.55% and 98.92%, respectively. A mean of 462.8 frames containing distracting CADe detections per colonoscopy were avoided using the convolutional neuronal network. This accounted for 95.6% of all distracting CADe detections. Conclusions Detection of endoscopic instruments in colonoscopy using artificial intelligence technology is reliable and achieves high sensitivity and specificity. Accordingly, the new convolutional neuronal network could be used to reduce distracting CADe detections during endoscopic procedures. Thus, our study demonstrates the great potential of artificial intelligence technology beyond mucosal assessment.
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- 2022
12. autoAssembler: Automatic Reconstruction of Laser-Cut 3D Models
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Ingo Apel, Laurenz Seidel, Erik Brendel, Conrad Lempert, Markus Brand, Lukas Rambold, Thijs Roumen, and Patrick Baudisch
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Minimum bounding box ,Computer science ,Laser cutting ,Process (computing) ,Beam search ,Contrast (statistics) ,Edge (geometry) ,Symmetry (geometry) ,Algorithm ,Parametric statistics - Abstract
Recent research showed how to import laser cut 3D models encoded in the form of 2D cutting plans into a 3D editor (assembler3 [28]), which allows users to perform parametric manipulations on such models. In contrast to assembler3 , which requires users to perform this process manually, we present autoAssembler, which performs this process automatically. AutoAssembler uses a beam search algorithm to search possible ways of assembling plates. It uses joints on these plates to combine them into assembly candidates. It thereby preferably pursues candidates (1) that have no intersecting plates, (2) that fit into a small bounding box, (3) that use plates whose joints fit together well, (4) that do not add many unpaired joints, (5) that make use of constraints posed by other plates, and (6) that conform to symmetry axes of the plates. This works for models that have at least one edge joint (finger or t-joint). In our technical evaluation, we imported 66 models using autoAssembler. AutoAssembler assembled 79% of those models fully automatically; another 18% of models required on average 2.7 clicks of post-processing, for an overall success rate of 97%.
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- 2021
13. Kono-S Anastomosis in Crohn’s Disease: A Retrospective Study on Postoperative Morbidity and Disease Recurrence in Comparison to the Conventional Side-To-Side Anastomosis
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Matthias Kelm, Joachim Reibetanz, Mia Kim, Kathrin Schoettker, Markus Brand, Alexander Meining, Christoph-Thomas Germer, and Sven Flemming
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ddc:610 ,General Medicine ,Crohn’s disease ,surgical therapy ,ileocecal resection ,Kono-S anastomosis - Abstract
Introduction: The rates of postoperative recurrence following ileocecal resection due to Crohn’s disease remain highly relevant. Despite this fact, while the Kono-S anastomosis technique initially demonstrated promising results, robust evidence is still lacking. This study aimed to analyze the short- and long-term outcomes of the Kono-S versus side-to-side anastomosis. Methods: A retrospective single-center study was performed including all patients who received an ileocecal resection between 1 January 2019 and 31 December 2021 at the Department of Surgery at the University Hospital of Wuerzburg. Patients who underwent conventional a side-to-side anastomosis were compared to those who received a Kono-S anastomosis. The short- and long-term outcomes were analyzed for all patients. Results: Here, 29 patients who underwent a conventional side-to-side anastomosis and 22 patients who underwent a Kono-S anastomosis were included. No differences were observed regarding short-term postoperative outcomes. The disease recurrence rate postoperatively was numerically lower following the Kono-S anastomosis (median Rutgeert score of 1.7 versus 2.5), with a relevantly increased rate of patients in remission (17.2% versus 31.8%); however, neither of these results reached statistical significance. Conclusion: The Kono-S anastomosis method is safe and feasible and potentially decreases the severity of postoperative disease remission.
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- 2022
14. Assembler3: 3D Reconstruction of Laser-Cut Models
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Conrad Lempert, Markus Brand, Carl Goedecken, Ingo Apel, Yannis Kommana, Patrick Baudisch, Thijs Roumen, Erik Brendel, Muhammad Abdullah, Pascal Crenzin, Lukas Rambold, Laurenz Seidel, and Ben Hurdelhey
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Engineering drawing ,Matching (statistics) ,Laser cutting ,Computer science ,05 social sciences ,3D reconstruction ,020207 software engineering ,02 engineering and technology ,Reuse ,Laser ,law.invention ,Workflow ,law ,0202 electrical engineering, electronic engineering, information engineering ,0501 psychology and cognitive sciences ,Joint (audio engineering) ,050107 human factors ,Parametric statistics - Abstract
We present Assembler3 a software tool that allows users to perform 3D parametric manipulations on 2D laser cutting plans. Assembler3 achieves this by semi-automatically converting 2D laser cutting plans to 3D, where users modify their models using available 3D tools (kyub), before converting them back to 2D. In our user study, this workflow allowed users to modify models 10x faster than using the traditional approach of editing 2D cutting plans directly. Assembler3 converts models to 3D in 5 steps: (1) plate detection, (2) joint detection, (3) material thickness detection, (4) joint matching based on hashed joint "signatures", and (5) interactive reconstruction. In our technical evaluation, Assembler3 was able to reconstruct 100 of 105 models. Once 3D-reconstructed, we expect users to store and share their models in 3D, which can simplify collaboration and thereby empower the laser cutting community to create models of higher complexity.
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- 2021
15. Early Ileocecal Resection Is an Effective Therapy in Isolated Crohn’s Disease
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Matthias, Kelm, Friedrich, Anger, Robin, Eichlinger, Markus, Brand, Mia, Kim, Joachim, Reibetanz, Katica, Krajinovic, Christoph-Thomas, Germer, Nicolas, Schlegel, and Sven, Flemming
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lcsh:R ,ileocecal resection ,lcsh:Medicine ,ddc:610 ,surgical therapy ,Article ,Crohn’s Disease - Abstract
Despite the increasing incidence and prevalence of Crohn’s Disease (CD), no curative options exist and treatment remains complex. While therapy has mainly focused on medical approaches in the past, growing evidence reveals that in cases of limited inflammation, surgery can suffice as an alternative primary treatment. We retrospectively assessed the disease course and outcomes of 103 patients with terminal Ileitis who underwent primary surgery (n = 29) or received primary medical treatment followed by surgery (n = 74). Primary endpoint was the need for immunosuppressive medication after surgical treatment (ileocecal resection, ICR) during a two-years follow-up. Rates for laparoscopic ICR were enhanced in case of early surgery, but no differences were seen for postoperative complications. In case of immunosuppressive medication, patients with ICR at an early state of disease needed significantly less anti-inflammatory medication during the two-year postoperative follow-up compared to patients who were primarily treated medically. Furthermore, in a subgroup analysis for patients with localized ileocecal disease manifestation, early surgery consistently resulted in a decreased amount of medical therapy postoperatively. In conclusion primary ICR is safe and effective in patients with limited CD, and the need for immunosuppressive medication during the postoperative follow-up is low compared to patients receiving surgery at a later stage of disease.
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- 2021
16. Endoscopic full thickness resection vs. transanal endoscopic microsurgery for local treatment of rectal neuroendocrine tumors - a retrospective analysis
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Marko Kornmann, Alexander Meining, Stanislaus Reimer, Markus Brand, Sven Flemming, and Joachim Reibetanz
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Transanal Endoscopic Microsurgery ,medicine.medical_specialty ,Microsurgery ,medicine.medical_treatment ,Rectum ,Neuroendocrine tumors ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Retrospective analysis ,Medicine ,Humans ,Full thickness resection ,ddc:610 ,Stage (cooking) ,R0 resection ,Retrospective Studies ,Endoscopic full thickness resection (eFTR) ,business.industry ,Rectal Neoplasms ,Neuroendocrine tumor (NET) ,Transanal endoscopic microsurgery (TEM) ,Gastroenterology ,Hepatology ,medicine.disease ,Surgery ,Neuroendocrine Tumors ,medicine.anatomical_structure ,Treatment Outcome ,030220 oncology & carcinogenesis ,030211 gastroenterology & hepatology ,Original Article ,business ,Full-thickness resection device (FTRD) - Abstract
Purpose Local treatment of small well-differentiated rectal neuroendocrine tumors (NETs) is recommended by current guidelines. However, although several endoscopic methods have been established, the highest R0 rate is achieved by transanal endoscopic microsurgery (TEM). Since a recently published study about endoscopic full thickness resection (eFTR) showed a R0 resection rate of 100%, the aim of this study was to evaluate both methods (eFTR vs. TEM). Methods We retrospectively analyzed all patients with rectal NET treated either by TEM (1999–2018) or eFTR (2016–2019) in two tertiary centers (University Hospital Wuerzburg and Ulm). We analyzed clinical, procedural, and histopathological outcomes in both groups. Results Twenty-eight patients with rectal NET received local treatment (TEM: 13; eFTR: 15). Most tumors were at stage T1a and grade G1 or G2 (in the TEM group two G3 NETs were staged T2 after neoadjuvant chemotherapy). In both groups, similar outcomes for en bloc resection rate, R0 resection rate, tumor size, or specimen size were found. No procedural adverse events were noted. Mean procedure time in the TEM group was 48.9 min and 19.2 min in the eFTR group. Conclusion eFTR is a convincing method for local treatment of small rectal NETs combining high safety and efficacy with short interventional time.
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- 2021
17. Multimodal Non-Destructive In Situ Observation of Crystallinity Changes in High-Density Polyethylene Samples with Relation to Optical Parameters during Tensile Deformation
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Karoline Felbermayer, Sandrine van Frank, Bettina Heise, Markus Brandstetter, Christian Rankl, Harald Ladner, and Peter Burgholzer
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crystallinity ,HDPE ,optical parameters ,terahertz spectroscopy ,optical coherence tomography ,infrared spectroscopy ,Chemical technology ,TP1-1185 - Abstract
Many non-destructive optical testing methods are currently used for material research, providing various information about material parameters. At RECENDT, a multimodal experimental setup has been designed that combines terahertz (THz) spectroscopy, optical coherence tomography (OCT), infrared (IR), and Raman spectroscopy with a tensile test stage. This setup aims to gather material information such as crystallinity and optical parameters of high-density polyethylene (HDPE) during a tensile test. The setup compares common IR and Raman spectroscopy and the less common optical methods THz and OCT. Complementarity is achieved through different frequency ranges and measurement approaches, resulting in different measured optical material parameters and depths. During tensile testing, HDPE samples with varying crystallinity were analysed, and the determined optical parameters such as refractive index, birefringence, scattering coefficient of decay, and penetration depth can be correlated with the change in crystallinity. These findings demonstrate that the optical methods and their outcomes can be interconnected. With further optimization of the experimental setup, it would be possible to observe the alignment of fibres in fibre composite panels and the stress distribution of polymers effectively. This opens interesting possibilities for polymer characterization in the future, including quality control during moulding processes and material testing.
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- 2024
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18. The challenge of sensor selection, long term-sensor operation and data evaluation in inter- -institutional long term monitoring projects (lessons learned in the MOSES project)
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Uta Koedel, Philipp Fischer, Madlen Friedrich, Markus Brand, Peter Dietrich, Holger Brix, Ingeborg Bussmann, and Dorit Kerschke
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Accuracy and precision ,Data processing ,business.industry ,Real-time computing ,Modular design ,Field (computer science) ,Term (time) ,Environmental data ,Earth system science ,13. Climate action ,Environmental science ,14. Life underwater ,business ,Scale (map) - Abstract
Measuring environmental variables over longer times in coastal marine environments is a challenge in regard to sensor maintenance and data processing of continuously produced comprehensive datasets. In the project “MOSES” (Modular Observation Solutions for Earth Systems), this procedure became even more complicated because seven large Helmholtz centers from the research field Earth and Environment (E&E) within the framework of the German Ministery of Educatiopn and Research (BMBF) work together to design and construct a large scale monitoring network across earth compartments to study the effects of short-term events on long term environmental trends. This requires the development of robust and standardized automated data acquisition and processing routines, to ensure reliable, accure and precise data.Here, the results of two intercomparison workshops on senor accuracy and precicion for selected environmental variables are presented. Environmental sensors which were to be used in MOSES campaigns on hydrological extremes (floods and draughts) in the Elbe catchment and the adjacent coastal areas in the North Sea in 2019 to 2020 were compared for selected parameters (temperature, salinity, chlorophyll-A, turbidity and methane) in the same experimentally controlled water body, assuming that all sensors provide comparable data. Results were analyzed with respect to individual sensor accuracy and precision related to an “assumed” real value as well as with respect to a cost versus accuracy/precision index for measuring specific environmental data. The results show, that accuracy and precision of sensors do not necessarily correlate with the price of the sensors and that low cost sensors may provide the same or even higher accuracy and precision values as even the highest price sensor types.
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- 2020
19. Surgical Results and Complications of Cochlear Implantation in Far-Advanced Otosclerosis
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Markus Brand, Søren Foghsgaard, Niels West, and Per Cayé-Thomasen
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Male ,medicine.medical_specialty ,Denmark ,Stapes Surgery ,Tertiary Care Centers ,03 medical and health sciences ,Postoperative Complications ,0302 clinical medicine ,Vertigo ,otorhinolaryngologic diseases ,medicine ,Humans ,030223 otorhinolaryngology ,Cochlear implantation ,Retrospective Studies ,biology ,business.industry ,Retrospective cohort study ,General Medicine ,Perioperative ,medicine.disease ,biology.organism_classification ,Cochlear Implantation ,Facial nerve ,Surgery ,Cochlear Implants ,Otosclerosis ,Treatment Outcome ,Otorhinolaryngology ,030220 oncology & carcinogenesis ,Vestibule ,Female ,Complication ,business - Abstract
Objective To report surgical results and complications of cochlear implantation in patients with far-advanced otosclerosis (FAO). Materials and methods This was a retrospective chart review of surgical results in terms of electrode insertion as well as peri- and postoperative complications. Ten cochlear implantations (CIs) were performed in eight patients with FAO. A prior stapedotomy had been performed in all cases. Results Full electrode insertion was achieved in nine of the 10 operations (90%) and partial insertion in one operation. An unintended opening of the vestibule during drilling was the only perioperative complication. Postoperative complications occurred as two cases of vertigo (one prolonged). No chorda tympani syndrome and no cases of facial nerve stimulation were noted. Conclusion Although based on a limited number of cases, we conclude that full electrode insertion can be achieved in almost all cases and that major complications are infrequent in CI in patients with FAO. Postoperative vertigo appears to be the most commonly occurring complication.
- Published
- 2017
20. First year of practical experiences of the new Arctic AWIPEV-COSYNA cabled Underwater Observatory in Kongsfjorden, Spitsbergen
- Author
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Philipp Fischer, Uwe Posner, Markus Brand, Max Schwanitz, Friedhelm Schröder, and Reiner Loth
- Subjects
0106 biological sciences ,lcsh:GE1-350 ,geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,010604 marine biology & hydrobiology ,lcsh:Geography. Anthropology. Recreation ,Sampling (statistics) ,Fjord ,01 natural sciences ,Oceanography ,Arctic ,lcsh:G ,Abundance (ecology) ,Littoral zone ,Environmental science ,14. Life underwater ,Species richness ,Underwater ,lcsh:Environmental sciences ,0105 earth and related environmental sciences ,Global biodiversity - Abstract
A combined year-round assessment of selected oceanographic data and a macrobiotic community assessment was performed from October 2013 to November 2014 in the littoral zone of the Kongsfjorden polar fjord system on the western coast of Svalbard (Norway). State of the art remote controlled cabled underwater observatory technology was used for daily vertical profiles of temperature, salinity, and turbidity together with a stereo-optical assessment of the macrobiotic community, including fish. The results reveal a distinct seasonal cycle in total species abundances, with a significantly higher total abundance and species richness during the polar winter when no light is available underwater compared to the summer months when 24 h light is available. During the winter months, a temporally highly segmented community was observed with respect to species occurrence, with single species dominating the winter community for restricted times. In contrast, the summer community showed an overall lower total abundance as well as a significantly lower number of species. The study clearly demonstrates the high potential of cable connected remote controlled digital sampling devices, especially in remote areas, such as polar fjord systems, with harsh environmental conditions and limited accessibility. A smart combination of such new digital sampling methods with classic sampling procedures can provide a possibility to significantly extend the sampling time and frequency, especially in remote and difficult to access areas. This can help to provide a sufficient data density and therefore statistical power for a sound scientific analysis without increasing the invasive sampling pressure in ecologically sensitive environments.
- Published
- 2017
21. Species composition and abundance of the shallow water fish community of Kongsfjorden, Svalbard
- Author
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Philipp Fischer and Markus Brand
- Subjects
0106 biological sciences ,biology ,Range (biology) ,Ecology ,010604 marine biology & hydrobiology ,Biodiversity ,Species diversity ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Demersal zone ,Myoxocephalus scorpius ,Oceanography ,13. Climate action ,Abundance (ecology) ,Sculpin ,Gadus ,14. Life underwater ,General Agricultural and Biological Sciences - Abstract
Projections show that climate change will lead to structural change in Arctic ecosystems. Studies project the extinction of local species and intense species invasion to the Arctic Ocean. A lack of basic biological data about the Arctic shallow water fish community will make it hard to assess whether these communities will change or not. Baseline studies in combination with future reassessments are needed to establish a basic knowledge about the change of these communities. This study provides a quantitative first time description of the shallow water fish community of Kongsfjorden, Svalbard. The fish assemblage in the depth range from 3 to 12 m was determined with respect to abundance and species composition. Among a total sample size of 2804 specimens, the presence of 12 fish species and one family (Liparidae) was detected. Myoxocephalus scorpius (shorthorn sculpin) (74.9 %), Gadus morhua (Atlantic cod) (17.2 %), and Gymnocanthus tricuspis (Arctic staghorn sculpin) (3.8 %) were identified as the most abundant species across all sampling sites. A signif- icant relationship between algal coverage and fish abun- dance was detected. Furthermore, we demonstrated a fjord inward increase in biodiversity along the south shore that might be correlated with a change in hydrographic regime.
- Published
- 2016
22. Percolation and Contaminant Transport in Road Embankments with and without Technical Safeguards to Reduce Percolation – Lysimeter Experiments
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R. Hilliges, Manfred Schnell, Birgit Kocher, Astrid Tiffert, Markus Brand, Tanja Marks, and Michael Endres
- Subjects
pollutant control ,Lysimeter ,road runoff ,Environmental engineering ,technical safeguards ,Soil classification ,02 engineering and technology ,010501 environmental sciences ,Soil type ,containmant leaching ,01 natural sciences ,020401 chemical engineering ,Loam ,Soil water ,Environmental science ,0204 chemical engineering ,Drainage ,Leaching (agriculture) ,Surface runoff ,0105 earth and related environmental sciences - Abstract
Alternative materials, like recycling materials, industrial by-products and soils already influenced by human activities (e.g. urban soils) are commonly accepted as building material in earthwork constructions. The risk of contaminant leaching from these materials can be limited by reducing the amount of percolating water. Technical safeguards are means to achieve this, but they must be adapted to the requirements of road construction. The research project aims to better knowledge of the percolation and leaching processes in road embankments constructed from alternative materials with different technical safeguards.The input and behavior of water and contaminants from re-used soils and road runoff is measured in eight field lysimeters at an urban road in an enterprise zone in Augsburg, southern Germany with about 9,700 vehicles per day. Each lysimeter contains the cut out of an embankment. The technical safeguards aim to decrease percolation and include a capillary barrier / drainage layer from geotextile and a second one from gravel, a bituminous film of 1kg/m2 and a modified mineral sealing of 10cm.A sandy gravel and a loamy soil were each used for construction of the embankment cut out in four lysimeters. The soils were spiked with a low contamination of Cd, Cu and CN- to test the efficiency of the technical safeguards. In the percolate water of the lysimeters as well as in the road runoff the pH value, electrical conductivity and the concentrations of sulphate, chloride, As, Pb, CN-, Cr, Cu, Hg, Ni, Mo, Sb, Tl, V and Zn have been analyzed in two-week composite samples since July of 2010. The amount of road runoff, lysimeter runoff and percolating water with its electrical conductivity are measured continuously. It has to be noted that measures were taken during a testing period in order to solve imperfections in the test set-up. These measures will have affected the observations presented.Results show that the unfiltered road runoff shows considerable concentrations of Zn and also elevated concentrations of Pb, as expected from former experience and literature. Up to now, all embankment types lead to a strong retention of these two substances. However, elevated Zn and Pb concentrations can be found in the percolating water during times of high chloride concentrations originating from deicing salt. Furthermore it was shown that the average contaminant leaching of each lysimeter was relatively small during the measurement period.Changes in concentrations of other parameters seem to be induced mainly by high chloride content of the infiltrating road runoff, but the time of occurrence of the changes in the effluent as well as the temporal variations depend also on the soil type, soil pH and the technical safeguards. Additionally, it seems that the soil type has a stronger influence on the percolation process compared to the different technical safeguards. Possible reasons will be discussed.
- Published
- 2016
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23. Sensor for Rapid In-Field Classification of Cannabis Samples Based on Near-Infrared Spectroscopy
- Author
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Robert Zimmerleiter, Wolfgang Greibl, Gerold Meininger, Kristina Duswald, Günther Hannesschläger, Paul Gattinger, Matthias Rohm, Christian Fuczik, Robert Holzer, and Markus Brandstetter
- Subjects
cannabis analysis ,near-infrared spectroscopy ,handheld sensor ,law enforcement ,partial least squares discriminant analysis ,forensic science ,Chemical technology ,TP1-1185 - Abstract
A rugged handheld sensor for rapid in-field classification of cannabis samples based on their THC content using ultra-compact near-infrared spectrometer technology is presented. The device is designed for use by the Austrian authorities to discriminate between legal and illegal cannabis samples directly at the place of intervention. Hence, the sensor allows direct measurement through commonly encountered transparent plastic packaging made from polypropylene or polyethylene without any sample preparation. The measurement time is below 20 s. Measured spectral data are evaluated using partial least squares discriminant analysis directly on the device’s hardware, eliminating the need for internet connectivity for cloud computing. The classification result is visually indicated directly on the sensor via a colored LED. Validation of the sensor is performed on an independent data set acquired by non-expert users after a short introduction. Despite the challenging setting, the achieved classification accuracy is higher than 80%. Therefore, the handheld sensor has the potential to reduce the number of unnecessarily confiscated legal cannabis samples, which would lead to significant monetary savings for the authorities.
- Published
- 2024
- Full Text
- View/download PDF
24. Diffraction-limited hyperspectral mid-infrared single-pixel microscopy
- Author
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Alexander Ebner, Paul Gattinger, Ivan Zorin, Lukas Krainer, Christian Rankl, and Markus Brandstetter
- Subjects
Medicine ,Science - Abstract
Abstract In this contribution, we demonstrate a wide-field hyperspectral mid-infrared (MIR) microscope based on multidimensional single-pixel imaging (SPI). The microscope employs a high brightness MIR supercontinuum source for broadband (1.55 $$\upmu \hbox {m}$$ μ m –4.5 $$\upmu \hbox {m}$$ μ m ) sample illumination. Hyperspectral imaging capability is achieved by a single micro-opto-electro-mechanical digital micromirror device (DMD), which provides both spatial and spectral differentiation. For that purpose the operational spectral bandwidth of the DMD was significantly extended into the MIR spectral region. In the presented design, the DMD fulfills two essential tasks. On the one hand, as standard for the SPI approach, the DMD sequentially masks captured scenes enabling diffraction-limited imaging in the tens of millisecond time-regime. On the other hand, the diffraction at the micromirrors leads to dispersion of the projected field and thus allows for wavelength selection without the application of additional dispersive optical elements, such as gratings or prisms. In the experimental part, first of all, the imaging and spectral capabilities of the hyperspectral microscope are characterized. The spatial and spectral resolution is assessed by means of test targets and linear variable filters, respectively. At a wavelength of 4.15 $$\upmu \hbox {m}$$ μ m a spatial resolution of 4.92 $$\upmu \hbox {m}$$ μ m is achieved with a native spectral resolution better than 118.1 nm. Further, a post-processing method for drastic enhancement of the spectral resolution is proposed and discussed. The performance of the MIR hyperspectral microsopce is demonstrated for label-free chemical imaging and examination of polymer compounds and red blood cells. The acquisition and reconstruction of Hadamard sampled 64 $$\times$$ × 64 images is achieved in 450 ms and 162 ms, respectively. Thus, combined with an unprecedented intrinsic flexibiliy gained by a tunable field of view and adjustable spatial resolution, the demonstrated design drastically improves the sample throughput in MIR chemical and biomedical imaging.
- Published
- 2023
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25. First year of the new Arctic AWIPEV-COSYNA cabled Underwater Observatory in Kongsfjorden, Spitsbergen
- Author
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Friedhelm Schröder, Reiner Loth, Philipp Fischer, Uwe Posner, Max Schwanitz, and Markus Brand
- Subjects
0106 biological sciences ,geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,010604 marine biology & hydrobiology ,Fjord ,01 natural sciences ,Salinity ,Oceanography ,Arctic ,Abundance (ecology) ,Observatory ,Littoral zone ,Environmental science ,14. Life underwater ,Species richness ,0105 earth and related environmental sciences ,Global biodiversity - Abstract
A combined year round assessment of selected oceanographic data and a macrobiotic community assessment was performed from October 2013 to November 2014 in the littoral zone of the polar fjord systems Kongsfjorden on the west coast of Svalbard (Norway). A state of the art remote controlled cabled underwater observatory technology was used for daily vertical profiles of temperature, salinity and turbidity together with a stereo-optical assessment of the macrobiotic community, including fish. The results reveal a distinct seasonal cycle in total species abundances with a significantly higher total abundance and species richness during the polar winter when no light is available under water compared to the summer months when 24-h light is available. During the winter months, a temporally highly segmented community was observed with respect to species occurrence with single species dominating the winter community for restricted times. In contrast, the summer community showed an overall lower total abundance, as well as a significantly lower number of species. The study clearly demonstrates the high potential of cable connected remote controlled digital sampling devices, especially in remote areas, such as the polar fjord systems, with harsh environmental conditions and limited accessibility. A smart combination of such new digital “sampling” methods with classic sampling procedures can provide a possibility to significantly extend the sampling time and frequency especially in remote and difficult to access areas. This can help to provide a sufficient data density and therefore statistical power for a sound scientific analysis without increasing the invasive sampling pressure in ecologically sensitive environments.
- Published
- 2016
26. IKKβ binds NLRP3 providing a shortcut to inflammasome activation for rapid immune responses
- Author
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Yaw Asare, Margarita Shnipova, Luka Živković, Christina Schlegl, Federica Tosato, Arailym Aronova, Markus Brandhofer, Laura Strohm, Nathalie Beaufort, Rainer Malik, Christian Weber, Jürgen Bernhagen, and Martin Dichgans
- Subjects
Medicine ,Biology (General) ,QH301-705.5 - Published
- 2022
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27. Klotho and phosphate are modulators of pathologic uremic cardiac remodeling
- Author
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Han Jun Cho, John M. Shelton, Masaya Takahashi, Jean Paek, Makoto Kuro-o, Ming Chang Hu, Mingjun Shi, Beverley Adams-Huet, Joseph A. Hill, Markus Brand, Ansel P. Amaral, Myles Wolf, Christian Faul, Masatomo Taniguchi, Orson W. Moe, and Kathy Hill
- Subjects
medicine.medical_specialty ,Heart disease ,Normal diet ,Cardiomegaly ,Mice, Transgenic ,urologic and male genital diseases ,Sensitivity and Specificity ,Muscle hypertrophy ,Phosphates ,Mice ,Random Allocation ,Fibrosis ,Internal medicine ,Up Front Matters ,Renin–angiotensin system ,Medicine ,Animals ,Myocytes, Cardiac ,Renal Insufficiency, Chronic ,Klotho ,Klotho Proteins ,Cells, Cultured ,Glucuronidase ,Uremia ,Ventricular Remodeling ,business.industry ,General Medicine ,Fibroblasts ,medicine.disease ,Angiotensin II ,female genital diseases and pregnancy complications ,Fibroblast Growth Factors ,Disease Models, Animal ,Fibroblast Growth Factor-23 ,Endocrinology ,Nephrology ,Heart Function Tests ,business ,Biomarkers - Abstract
Cardiac dysfunction in CKD is characterized by aberrant cardiac remodeling with hypertrophy and fibrosis. CKD is a state of severe systemic Klotho deficiency, and restoration of Klotho attenuates vascular calcification associated with CKD. We examined the role of Klotho in cardiac remodeling in models of Klotho deficiency-genetic Klotho hypomorphism, high dietary phosphate intake, aging, and CKD. Klotho-deficient mice exhibited cardiac dysfunction and hypertrophy before 12 weeks of age followed by fibrosis. In wild-type mice, the induction of CKD led to severe cardiovascular changes not observed in control mice. Notably, non-CKD mice fed a high-phosphate diet had lower Klotho levels and greatly accelerated cardiac remodeling associated with normal aging compared with those on a normal diet. Chronic elevation of circulating Klotho because of global overexpression alleviated the cardiac remodeling induced by either high-phosphate diet or CKD. Regardless of the cause of Klotho deficiency, the extent of cardiac hypertrophy and fibrosis correlated tightly with plasma phosphate concentration and inversely with plasma Klotho concentration, even when adjusted for all other covariables. High-fibroblast growth factor-23 concentration positively correlated with cardiac remodeling in a Klotho-deficient state but not a Klotho-replete state. In vitro, Klotho inhibited TGF-β1-, angiotensin II-, or high phosphate-induced fibrosis and abolished TGF-β1- or angiotensin II-induced hypertrophy of cardiomyocytes. In conclusion, Klotho deficiency is a novel intermediate mediator of pathologic cardiac remodeling, and fibroblast growth factor-23 may contribute to cardiac remodeling in concert with Klotho deficiency in CKD, phosphotoxicity, and aging.
- Published
- 2014
28. Coronary flow regulation in mouse heart during hypercapnic acidosis: role of NO and its compensation during eNOS impairment
- Author
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Anke Heintz, Andreas Deussen, Markus Brand, Thea Koch, and M. Damm
- Subjects
Male ,medicine.medical_specialty ,Nitric Oxide Synthase Type III ,Physiology ,Nitric Oxide ,Nitric oxide ,Glibenclamide ,Hypercapnia ,chemistry.chemical_compound ,Mice ,Potassium Channels, Calcium-Activated ,KATP Channels ,Enos ,Physiology (medical) ,Internal medicine ,Coronary Circulation ,medicine ,Animals ,Acidosis ,biology ,business.industry ,Receptors, Adenosine A2 ,biology.organism_classification ,medicine.disease ,Adenosine ,Nitric oxide synthase ,Mice, Inbred C57BL ,Respiratory acidosis ,Endocrinology ,NG-Nitroarginine Methyl Ester ,chemistry ,Anesthesia ,Circulatory system ,biology.protein ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,medicine.drug - Abstract
Aims This study addressed the hypotheses that the hypercapnic flow response in wild-type (WT) mouse heart is mainly mediated by nitric oxide (NO) and, thus, severely blunted in endothelial nitric oxide synthase knockout (eNOS-KO) mice and in WT mice after continuous pharmacological block (2 weeks) of NOS enzymes (WT-LN). Methods and results Step changes of arterial pCO2 were performed in isolated perfused hearts ( n = 105). Contributions of NOS (L-NAME, TRIM), cyclooxygenase (indomethacin), epoxyeicosanotrienes (miconazole), adenosine A2A-receptors (SCH 58261), KV-channels (4-AP), KCa-channels (TEA), and KATP-channels (glibenclamide) were studied in WT and eNOS-KO mouse hearts. Change of arterial pCO2 increased coronary flow by 31.3 ± 4% in WT, a response that was significantly decreased to 9.2 ± 6% after L-NAME. Additional glibenclamide infusion ( n = 5) completely abolished the steady-state flow increase during hypercapnic acidosis (−4.2 ± 2.3%, P = 0.004 vs. control). Hearts from eNOS-KO mice as well as WT-LN showed a fully preserved flow response insensitive towards NOS-blockade. Whereas indomethacin, miconazole, TEA, and SCH 58261 were ineffective to reduce the flow response, glibenclamide blunted it in eNOS-KO hearts. Conclusion NO-production and KATP-channel activation together may fully account for the steady-state hypercapnic flow response in mouse heart. However, chronic deletion of eNOS does not result in a reduced hypercapnic flow response. Enhanced activation of KATP-channels and potentially Kv-channels contributes to the compensatory mechanisms involved in the hypercapnic flow response when eNOS activity is absent.
- Published
- 2007
29. Designed CXCR4 mimic acts as a soluble chemokine receptor that blocks atherogenic inflammation by agonist-specific targeting
- Author
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Christos Kontos, Omar El Bounkari, Christine Krammer, Dzmitry Sinitski, Kathleen Hille, Chunfang Zan, Guangyao Yan, Sijia Wang, Ying Gao, Markus Brandhofer, Remco T. A. Megens, Adrian Hoffmann, Jessica Pauli, Yaw Asare, Simona Gerra, Priscila Bourilhon, Lin Leng, Hans-Henning Eckstein, Wolfgang E. Kempf, Jaroslav Pelisek, Ozgun Gokce, Lars Maegdefessel, Richard Bucala, Martin Dichgans, Christian Weber, Aphrodite Kapurniotu, and Jürgen Bernhagen
- Subjects
Science - Abstract
The development of specific anti-cytokine/chemokine therapeutic strategies for atherosclerotic disease is challenging. Here, the authors have designed a peptide-based ectodomain mimic of the chemokine receptor CXCR4 that selectively targets MIF but not CXCL12 and blocks experimental atherosclerosis in vivo.
- Published
- 2020
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30. The Role of Macrophage Migration Inhibitory Factor in Adipose-Derived Stem Cells Under Hypoxia
- Author
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Elena Hofmann, Josefin Soppert, Tim Ruhl, Epameinondas Gousopoulos, Simona Gerra, Gabriele Storti, Yuan Tian, Markus Brandhofer, Riccardo Schweizer, Seung-Yong Song, Nicole Lindenblatt, Norbert Pallua, Jürgen Bernhagen, and Bong-Sung Kim
- Subjects
adipose-derived stem cells ,macrophage migration inhibitory factor ,hypoxia ,cytokine ,chronic wounds ,Physiology ,QP1-981 - Abstract
Background: Adipose-derived stem cells (ASCs) are multipotent mesenchymal stem cells characterized by their strong regenerative potential and low oxygen consumption. Macrophage migration inhibitory factor (MIF) is a multifunctional chemokine-like cytokine that is involved in tissue hypoxia. MIF is not only a major immunomodulator but also is highly expressed in adipose tissue such as subcutaneous adipose tissue of chronic non-healing wounds. In the present study, we investigated the effect of hypoxia on MIF in ASCs isolated from healthy versus inflamed adipose tissue.Methods: Human ASCs were harvested from 17 patients (11 healthy adipose tissue samples, six specimens from chronic non-healing wounds). ASCs were treated in a hypoxia chamber at
- Published
- 2021
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31. QCL-based mid-infrared hyperspectral imaging of multilayer polymer oxygen barrier-films
- Author
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Robert Zimmerleiter, Ramin Nikzad-Langerodi, Cyril Ruckebusch, Matthias Godejohann, Jakob Kilgus, Kristina Duswald, and Markus Brandstetter
- Subjects
Quantum cascade laser ,Mid-infrared spectroscopy ,Hyperspectral imaging ,Multi-layer polymer film ,Principal component analysis ,Multivariate curve resolution ,Polymers and polymer manufacture ,TP1080-1185 - Abstract
In this work, mid-infrared hyperspectral images of multilayer polymer film (MLPF) cross sections are acquired with a high-speed quantum cascade laser (QCL) based mid-infrared microscope and analyzed using different data analysis techniques. The investigated MLPF is a polypropylene (PP) and ethylene-vinyl alcohol co-polymer (EVOH) composite commonly used for food packaging due to its outstanding barrier characteristics. Pure band integration of supposedly selective absorption bands for the two constituents of the MLPF is compared to principal component analysis (PCA) and multivariate curve resolution (MCR) algorithms regarding the ability to spatially resolve the differently composed areas in the MLPF. While both pure band integration and PCA are strongly affected by common physical artifacts in the spectral data, such as sample tilt, scattering or interference effects, MCR managed to give a clear picture of the composition of the MLPF, which matches the actual situation given by the manufacturing process. The obtained results can guide the way to the application of high-performance mid-infrared spectroscopic instrumentation for spatially resolved polymer analysis by meaningful interpretation of hyperspectral image data.
- Published
- 2021
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- View/download PDF
32. Clinical presentation and characteristics of lymphoma in the head and neck region
- Author
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Katharina Storck, Markus Brandstetter, Ulrich Keller, and Andreas Knopf
- Subjects
Head and neck ,Lymphoma ,Neck mass ,Symptom ,Tonsillitis ,Specialties of internal medicine ,RC581-951 - Abstract
Abstract Background The study analyses clinical characteristics of histologically defined head and neck (H&N) lymphoma to raise the awareness of ENT specialists to the leading symptoms. Method From 2003 to 2011, all patients with histologically defined H&N lymphoma from our clinic were evaluated. Results This study identified 221 patients with H&N lymphoma comprising 193 non-Hodgkin lymphomas (NHL) and 28 Hodgkin lymphomas (HL). Among NHL there were 77 indolent (iNHL), 110 aggressive (aNHL), six highly aggressive NHL and further 28 HL. Patients with highly aggressive NHL and HL were significantly younger (p
- Published
- 2019
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33. Towards Real-Time In-Situ Mid-Infrared Spectroscopic Ellipsometry in Polymer Processing
- Author
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Alexander Ebner, Robert Zimmerleiter, Kurt Hingerl, and Markus Brandstetter
- Subjects
ellipsometry ,quantum cascade laser ,in-line monitoring ,polymer films ,polymer processing ,real-time ,Organic chemistry ,QD241-441 - Abstract
Recent developments in mid-infrared (MIR) spectroscopic ellipsometry enabled by quantum cascade lasers (QCLs) have resulted in a drastic improvement in signal-to-noise ratio compared to conventional thermal emitter based instrumentation. Thus, it was possible to reduce the acquisition time for high-resolution broadband ellipsometric spectra from multiple hours to less than 1 s. This opens up new possibilities for real-time in-situ ellipsometry in polymer processing. To highlight these evolving capabilities, we demonstrate the benefits of a QCL based MIR ellipsometer by investigating single and multilayered polymer films. The molecular structure and reorientation of a 2.5 µm thin biaxially oriented polyethylene terephthalate film is monitored during a stretching process lasting 24.5 s to illustrate the perspective of ellipsometric measurements in dynamic processes. In addition, a polyethylene/ethylene vinyl alcohol/polyethylene multilayer film is investigated at a continuously varying angle of incidence (0∘– 50∘) in 17.2 s, highlighting an unprecedented sample throughput for the technique of varying angle spectroscopic ellipsometry in the MIR spectral range. The obtained results underline the superior spectral and temporal resolution of QCL ellipsometry and qualify this technique as a suitable method for advanced in-situ monitoring in polymer processing.
- Published
- 2021
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34. HemoPill Acute ® in Suspected Nonvariceal Upper Gastrointestinal Bleeding
- Author
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Vivantes Netzwerk für Gesundheit GmbH, University Hospital Freiburg, Sana Klinikum Offenbach, and Dr. med. Markus Brand, Senior Physician - Gastroenterologist
- Published
- 2024
35. Research Concerning the Bending Properties of Reconstituted Spruce Lumber Boards, Obtained by Edge-Cutting at 45° and Gluing
- Author
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Mihaela Porojan, Markus Brandstetter, Mihai Ispas, Bogdan Bedelean, and Mihaela Campean
- Subjects
spruce wood ,reconstituted lumber ,wood bonding at 45° ,density ,MOR ,MOE ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The best-possible valorization of each cut log is a priority. The aim of this research was to evaluate the potential of a solution for increasing the conversion efficiency of tapered logs, by edge-cutting the narrowest sideboards at 45° and joining them by gluing, in order to obtain usable lumber boards. The modality of obtaining the glued elements was described and the values of the density and bending properties (MOE and MOR) of these elements compared to solid wood elements taken from the same logs and the same position within each log was determined. The envisaged outcome was to determine if the bonded products are suited to be used as cores within laminated products for construction.
- Published
- 2021
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36. Spectral-Coding-Based Compressive Single-Pixel NIR Spectroscopy in the Sub-Millisecond Regime
- Author
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Paul Gattinger, Ivan Zorin, Christian Rankl, and Markus Brandstetter
- Subjects
single-pixel ,spectroscopy ,near-infrared ,DMD ,multiplexing ,spectral coding ,Chemical technology ,TP1-1185 - Abstract
In this contribution, we present a high-speed, multiplex, grating spectrometer based on a spectral coding approach that is founded on principles of compressive sensing. The spectrometer employs a single-pixel InGaAs detector to measure the signals encoded by an amplitude spatial light modulator (digital micromirror device, DMD). This approach leads to a speed advantage and multiplex sensitivity advantage atypical for standard dispersive systems. Exploiting the 18.2 kHz pattern rate of the DMD, we demonstrated 4.2 ms acquisition times for full spectra with a bandwidth of 450 nm (5250–4300 cm−1; 1.9–2.33 µm). Due to the programmability of the DMD, spectral regions of interest can be chosen freely, thus reducing acquisition times further, down to the sub-millisecond regime. The adjustable resolving power of the system accessed by means of computer simulations is discussed, quantified for different measurement modes, and verified by comparison with a state-of-the-art Fourier-transform infrared spectrometer. We show measurements of characteristic polymer absorption bands in different operation regimes of the spectrometer. The theoretical multiplex advantage of 8 was experimentally verified by comparison of the noise behavior of the spectral coding approach and a standard line-scan approach.
- Published
- 2021
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37. A Localized Analysis of the Sterilization Process by Direct Steam Monitoring
- Author
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Elisabeth Leiss-Holzinger, Karoline Felbermayer, Dzenan Ismic, Christian Rankl, Johannes Hillmann, and Markus Brandstetter
- Subjects
Sensors ,optical sensors ,optical fiber sensors ,infrared sensors ,monitoring ,process monitoring ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Steam sterilization is a standard tool in the field of healthcare and medical equipment as it is economical, effective, and reliable. Considering the increase of antibiotic resistance and the challenge in sterilizing narrow tubes used for keyhole surgery, a safe process control is required. To achieve this, a full understanding of the local dynamics of the sterilization process inside the sterilizer is crucial. In this paper, water condensation under high temperature and high pressure, focusing on sterilization conditions, is qualitatively analyzed. An infrared sensor system was designed supplied by two LEDs, at a steam-absorbing and a non-absorbing wavelength, respectively. The local water vapor concentration was directly detected by evaluating the absorbance of infrared light as it passes through steam. Based on the absorbance monitored by this optical sensor, the condition of the steam was classified with respect to saturation and the onset of condensation. For typical sterilization cycles, differences as well as identical behavior between the local sensor measurements and the global results calculated from the temperature and pressure sensors are discussed.
- Published
- 2017
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38. Application of a Novel Low-Cost Hyperspectral Imaging Setup Operating in the Mid-Infrared Region
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Jakob Kilgus, Robert Zimmerleiter, Kristina Duswald, Florian Hinterleitner, Gregor Langer, and Markus Brandstetter
- Subjects
hyperspectral imaging ,mid-infrared ,tunable Fabry-Pérot interferometer ,bolometer camera ,machine learning ,General Works - Abstract
In this contribution, we demonstrate the realization and application of a low-cost, flexible, small and fast hyperspectral imaging approach operating in the midinfrared fingerprint region where most molecules exhibit their fundamental vibrations. Following this approach, the recording of chemical images of macroscopic-sized samples at standoff distances in reflection geometry is possible. The optical setup is based on spectral identification by means of a MEMS-based Fabry-Pérot interferometer combined with 2D-snapshot spatial resolution using a bolometer camera. Results show the successful spatially resolved (resolution below 500 µm) chemical identification of different samples deposited on a metal surface (FOV = 6 × 5 cm) at a working distance of 35 cm.
- Published
- 2018
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39. Multi-disciplinary System Engineering and the Compatibility Modeling Language (U)CML
- Author
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Markus Brandstatter and Carolin Eckl
- Subjects
Micro Process ,Compatibility Management ,Product Life Cycle ,Phased Development ,Multi-Disciplinary System Model ,Information technology ,T58.5-58.64 ,Communication. Mass media ,P87-96 - Abstract
Over time, technical systems such as automobiles or spacecraft have grown more complex due to the incorporation of increasingly more and different components. The integration of these components, which are frequently designed and constructed within separate departments and companies may lead to malfunctioning systems as their interplay cannot be tested within the earlier phases of development. This paper introduces compatibility management as one solution to the problems of late component integration. Compatibility management is carried out on a common crossdomain model of the system and therefore allows to test compatibility early on. We show how compatibility management can be embedded into the phased development of ECSS-M-30A and present the (Unified) Compatibility Modeling Language ((U)CML), which is used for the underlying cross-domain model. A case study demonstrates the application of (U)CML in the development of a small satellite and explains different degrees of compatibility.
- Published
- 2009
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