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Measuring Metacognition of Direct and Indirect Parameters of Voluntary Movement [article]

Polina Arbuzova, Caroline Peters, Lukas Roed, Christina Koss, Heiko Maurer, Lisa K. Maurer, Hermann Mueller, Julius Verrel, Elisa Filevich
2020 bioRxiv   pre-print
We can make exquisitely precise movements without the apparent need for conscious monitoring. But can we monitor the low-level movement parameters when prompted? And what are the mechanisms that allow us to monitor our movements? To answer these questions, we designed a semi-virtual ball throwing task. On each trial, participants first threw a virtual ball by moving their arm (with or without visual feedback, or replayed from a previous trial) and then made a two-alternative forced choice on
more » ... resulting ball trajectory. They then rated their confidence in their decision. We measured metacognitive efficiency using meta-d'/d' and compared it between different informational domains of the first-order task (motor, visuomotor or visual information alone), as well as between two different versions of the task based on different parameters of the movement: proximal (position of the arm) or distal (resulting trajectory of the ball thrown). We found that participants were able to monitor their performance based on distal motor information as well as when proximal information was available. Their metacognitive efficiency was also equally high in conditions with different sources of information available. The analysis of correlations across participants revealed an unexpected result: while metacognitive efficiency correlated between informational domains (which would indicate domain-generality of metacognition), it did not correlate across the different parameters of movement. We discuss possible sources of this discrepancy and argue that specific first-order task demands may play a crucial role in our metacognitive ability and should be considered when making inferences about domain-generality based on correlations.
doi:10.1101/2020.05.14.092189 fatcat:eb3tr3vaqzdxjdpfbctsphooqi

Sophisticated Phishers Make More Spelling Mistakes: Using URL Similarity against Phishing [chapter]

Max-Emanuel Maurer, Lukas Höfer
2012 Lecture Notes in Computer Science  
Phishing attacks rise in quantity and quality. With short online lifetimes of those attacks, classical blacklist based approaches are not sucient to protect online users. While attackers manage to achieve high similarity between original and fraudulent websites, this fact can also be used for attack detection. In many cases attackers try to make the Internet address (URL) from a website look similar to the original. In this work, we present a way of using the URL itself for automated detection
more » ... f phishing websites by extracting and verifying dierent terms of a URL using search engine spelling recommendation. We evaluate our concept against a large test set of 8730 real phishing URLs. In addition, we collected scores for the visual quality of a subset of those attacks to be able to compare the performance of our tests for dierent attack qualities. Results suggest that our heuristics are able to mark 54.3% of the malicious URLs as suspicious. With increasing visual quality of the phishing websites, the number of URL characteristics that allow a detection increases, as well.
doi:10.1007/978-3-642-35362-8_31 fatcat:f7u4aipjnjcare3k7vnyfyxjym

Clinical experience with the artificial bone graft substitute Calcibon used following curettage of benign and low-grade malignant bone tumors

Joerg Friesenbichler, Werner Maurer-Ertl, Marko Bergovec, Lukas A. Holzer, Kathrin Ogris, Lukas Leitner, Andreas Leithner
2017 Scientific Reports  
Artificial bone graft substitutes, such as Calcibon, are becoming increasingly interesting as they do not cause donor site morbidity which is an advantage compared to autologous bone grafts. The aim of this study was to evaluate the efficacy and potential complications associated with the use of Calcibon. Twenty-seven patients with benign and low-grade malignant bone tumors were treated with curettage and refilling of the bony cavity. Based on the radiological classification system of Neer,
more » ... e lesions only comprised Grade I lesions, describing cysts that only require curettage and filling, but no additional treatment. At a mean follow up of six months we observed radiological consolidation without resorption of the bone graft substitute. These observations were also made at a mean follow-up of 13 and 32 months, respectively. According to the classification system of Goslings and Gouma we observed six surgical complications. Summing up, Calcibon seems to be a reliable bone graft substitute with low complication rates. However, delayed resorption should be expected. Calcibon seems to be an alternative to autologous bone grafts or allografts in adequate indications. Benign bone tumors and low-grade malignancies are usually treated with intralesional resection or curettage. After curettage, the bone cavity can be left unfilled or it can be refilled with autologous or allogenic material 1, 2 . The final result should be a full bony ingrowth and a remodeling of the graft into mature bone. A known side effect of autologous bone grafts originating from the iliac crest is donor side morbidity with risks like infection, delayed wound healing, neuro-vascular injuries, heterotopic ossification and local pain, which are the most commonly reported complication 2, 3 . As an alternative to autologous bone grafts, allogenic or artificial bone graft substitutes (ABGS), such as demineralized bone matrix, bone graft extenders, or bone morphogenic proteins, can be applied 2, 4-8 . However, allogenic materials have been reported to be immunogenicity and to transfer infectious diseases with complication rates for infection up to 12.2% 9, 10 . On the other hand, some bone void fillers in general have also been associated with higher complications rates up to 33% 1, 2, 5, 8, 11 . Bone graft extenders like ceramics, salts, or synthetic products, such as polymethylmethacrylate (PMMA), are often used to refill bone cavities as they provide the advantage that they are moldable and can be used to fill irregularly shaped defects. What is more, ABGS are freely available without any restrictions of access, there is no reason for disease transmission. Calcibon (Biomet, Warsaw, IN) is a synthetic bone graft substitute with osteo-conductive properties. It belongs to the family of α-tricalcium-phosphates (α-TCP). Calcibon is a chemical composition of 62.5% α-TCP, 26.8% dicalcium phoshate dihydrate, 8.9% calcium carbonate and 1.8% precipitated hydroxyapatite. In order to liquefy this mixture, 1% disodium hydrogen phosphate dodecahydrate has to be added with an ideal liquid-to-powder ratio of 0.35 mL/g 12 . However, a microporosity with a pore size of less than 1 μm is only present in 30 to 40% of the resulting graft 12 . Following its application to the cavity and drying, Calcibon's biomechanical properties Published: xx xx xxxx OPEN
doi:10.1038/s41598-017-02048-w pmid:28496119 pmcid:PMC5431777 fatcat:nuff4llapjairc32i7pnvp2ylm

Renal function is independently associated with circulating betatrophin

Lukas Maurer, Franziska Schwarz, Antje Fischer-Rosinsky, Nina Schlueter, Sebastian Brachs, Matthias Möhlig, Andreas Pfeiffer, Knut Mai, Joachim Spranger, Thomas Bobbert, Stefan Kiechl
2017 PLoS ONE  
OPEN ACCESS Citation: Maurer L, Schwarz F, Fischer-Rosinsky A, Schlueter N, Brachs S, Möhlig M, et al. (2017) Renal function is independently associated with circulating betatrophin.  ... 
doi:10.1371/journal.pone.0173197 pmid:28257453 pmcid:PMC5336269 fatcat:626t3676c5cbbnrtka44dsgr3a

Transferring the attoclock technique to velocity map imaging

Matthias Weger, Jochen Maurer, André Ludwig, Lukas Gallmann, Ursula Keller
2013 Optics Express  
Attosecond angular streaking measurements have revealed deep insights into the timing of tunnel ionization processes of atoms in intense laser fields. So far experiments of this type have been performed only with a cold-target recoil-ion momentum spectrometer (COLTRIMS). Here, we present a way to apply attosecond angular streaking experiments to a velocity map imaging spectrometer (VMIS) with few-cycle pulses at a repetition rate of 10 kHz and a high ionization yield per pulse.
more » ... photoelectron momentum distributions from strong-field ionization of helium with an elliptically polarized, sub-10-fs pulse were retrieved by tomographic reconstruction from the momentum space electron images and used for the analysis in the polarization plane.
doi:10.1364/oe.21.021981 pmid:24104091 fatcat:nzlgphygcnelzpxk4zmjkrjty4

The accuracy of digital templating in uncemented total hip arthroplasty

Lukas A. Holzer, Georg Scholler, Stefan Wagner, Jörg Friesenbichler, Werner Maurer-Ertl, Andreas Leithner
2018 Archives of Orthopaedic and Trauma Surgery  
Introduction Preoperative planning is an essential part of total hip arthroplasty (THA). It facilitates the surgical procedure, helps to provide the correct implant size and aims at restoring biomechanical conditions. In recent times, surgeons rely more and more on digital templating techniques. Although the conversion to picture archiving and communication system had many positive effects, there are still problems that have to be taken into consideration. Objectives The core objective was to
more » ... aluate the impact of the planners' experience on the accuracy of predicting component size in digital preoperative templating of THA. In addition, the influence of overweight and obesity (according to WHO-criteria), patient's sex and component design on the accuracy of preoperative planning have been analysed. Materials and methods The retrospective study included 632 consecutive patients who had primary uncemented THA. Digital templating was done using "syngo-EndoMap" software by Siemens Medical Solutions AG. Mann-Whitney U test and Kruskal-Wallis test have been used for statistical analysis. The accuracy of predicting component size has been evaluated by comparing preoperative planned sizes with implanted sizes as documented by the surgeons. The planner's experience was tested by comparing the reliability of preoperative planning done by senior surgeons or residents. The influence of BMI on predicting component size has been tested by comparing the accuracy of digital templating between different groups of BMI according to WHO-criteria. The same procedure has been done for evaluating the impact of patient´s sex and component design. Results The implant size was predicted exactly in 42% for the femoral and in 37% for the acetabular component. 87% of the femoral components and 78% of the acetabular cups were accurate within one size. Digital templating of femoral implant size was significantly more reliable when done by a senior surgeon. No difference was found for the acetabular component sizes. The BMI also had an impact on estimating the correct femoral implant size. In overweight patients, planning was significantly more inaccurate than normal weight people. Differences were seen in obese patients. However, these were not significant. Accuracy of acetabular components was not affected. The design of the prostheses and the patient's sex had no influence on predicting component size. Conclusions Inexperience and overweight are factors that correlate with inaccuracy of preoperative digital templating in femoral components, whereas acetabular components seem to be independent of these factors.
doi:10.1007/s00402-018-3080-0 pmid:30523444 fatcat:fwzv6mxphfhltjd752z5ryi52a

High-resolution Episcopic Microscopy (HREM) - Simple and Robust Protocols for Processing and Visualizing Organic Materials

Stefan H. Geyer, Barbara Maurer-Gesek, Lukas F. Reissig, Wolfgang J. Weninger
2017 Journal of Visualized Experiments  
We provide simple protocols for generating digital volume data with the high-resolution episcopic microscopy (HREM) method. HREM is capable of imaging organic materials with volumes up to 5 x 5 x 7 mm 3 in typical numeric resolutions between 1 x 1 x 1 and 5 x 5 x 5 µm 3 . Specimens are embedded in methacrylate resin and sectioned on a microtome. After each section an image of the block surface is captured with a digital video camera that sits on the phototube connected to the compound
more » ... head. The optical axis passes through a green fluorescent protein (GFP) filter cube and is aligned with a position, at which the bock holder arm comes to rest after each section. In this way, a series of inherently aligned digital images, displaying subsequent block surfaces are produced. Loading such an image series in three-dimensional (3D) visualization software facilitates the immediate conversion to digital volume data, which permit virtual sectioning in various orthogonal and oblique planes and the creation of volume and surface rendered computer models. We present three simple, tissue specific protocols for processing various groups of organic specimens, including mouse, chick, quail, frog and zebra fish embryos, human biopsy material, uncoated paper and skin replacement material. Video Link The video component of this article can be found at 20 . However, in contrast to the latter, HREM is capable of visualizing specimens with relative large volumes of up to 5 x 5 x 7 mm 3 in histological quality. A number of recent studies provide detailed characterizations and comparisons of advantages and disadvantages of the single imaging techniques and, for the sake of objectivity, we refer to those for further information regarding their limitations and potential fields of applications 4, 21, 22, 23, 24 . This study focuses on the HREM imaging method and aims to provide very simple protocols for generating HREM data of a broad spectrum of organic materials, as well as examples of their application. The workflow for creating HREM data is simple and applies to all materials that can Journal of Visualized Experiments
doi:10.3791/56071 pmid:28715372 pmcid:PMC5609318 fatcat:gpjslatfcrgwzmyvx7fu545exe

Workflow for Criticality Assessment Applied in Biopharmaceutical Process Validation Stage 1

Thomas Zahel, Lukas Marschall, Sandra Abad, Elena Vasilieva, Daniel Maurer, Eric Mueller, Patrick Murphy, Thomas Natschläger, Cécile Brocard, Daniela Reinisch, Patrick Sagmeister, Christoph Herwig
2017 Bioengineering  
Sandra Abad, Elena Vasilieva and Daniel Maurer conducted the necessary experiments in DoE approaches at small scale.  ...  Lukas Marschall assisted in the development of the retrospective power analysis method, wrote the manuscript and designed the illustrations.  ... 
doi:10.3390/bioengineering4040085 pmid:29023375 pmcid:PMC5746752 fatcat:knoyukf5cjdftpmbu4fb3swvse

Sexual Dimorphic Regulation of Body Weight Dynamics and Adipose Tissue Lipolysis

Verena Benz, Mandy Bloch, Sami Wardat, Christian Böhm, Lukas Maurer, Shokoufeh Mahmoodzadeh, Petra Wiedmer, Joachim Spranger, Anna Foryst-Ludwig, Ulrich Kintscher, Ingrid A. Dahlman
2012 PLoS ONE  
Successful reduction of body weight (BW) is often followed by recidivism to obesity. BW-changes including BW-loss and -regain is associated with marked alterations in energy expenditure (EE) and adipose tissue (AT) metabolism. Since these processes are sex-specifically controlled, we investigated sexual dimorphisms in metabolic processes during BWdynamics (gain-loss-regain). Research Design: Obesity was induced in C57BL/6J male (m) and female (f) mice by 15 weeks high-fat diet (HFD) feeding.
more » ... sequently BW was reduced (-20%) by caloric restriction (CR) followed by adaptive feeding, and a regain-phase. Measurement of EE, body composition, blood/organ sampling were performed after each feeding period. Lipolysis was analyzed ex-vivo in gonadal AT. Results: Male mice exhibited accelerated BW-gain compared to females (relative BW-gain m:140.563.2%; f:103.766.5%; p,0.001). In consonance, lean mass-specific EE was significantly higher in females compared to males during BW-gain. Under CR female mice reached their target-BW significantly faster than male mice (m:12.2 days; f:7.6 days; p,0.001) accompanied by a sustained sex-difference in EE. In addition, female mice predominantly downsized gonadal AT whereas the relation between gonadal and total body fat was not altered in males. Accordingly, only females exhibited an increased rate of forskolin-stimulated lipolysis in AT associated with significantly higher glycerol concentrations, lower RER-values, and increased AT expression of adipose triglyceride lipase (ATGL) and hormone sensitive lipase (HSL). Analysis of AT lipolysis in estrogen receptor alpha (ERa)-deficient mice revealed a reduced lipolytic rate in the absence of ERa exclusively in females. Finally, re-feeding caused BW-regain faster in males than in females. Conclusion: The present study shows sex-specific dynamics during BW-gain-loss-regain. Female mice responded to CR with an increase in lipolytic activity, and augmented lipid-oxidation leading to more efficient weight loss. These processes likely involve ERa-dependent signaling in AT and sexual dimorphic regulation of genes involved in lipid metabolism.
doi:10.1371/journal.pone.0037794 pmid:22662224 pmcid:PMC3360591 fatcat:n5nnf7zuvvfr7av6hopfjiquk4

Roman Ruins as an Experiment for Radiocarbon Dating of Mortar

Irka Hajdas, Jürgen Trumm, Georges Bonani, Carol Biechele, Mantana Maurer, Lukas Wacker
2012 Radiocarbon: An International Journal of Cosmogenic Isotope Research  
The remains of Vindonissa, the Roman legionary camp in Switzerland, have been the subject of extensive archaeological studies. Knowledge of the building time plays a role in reconstructions of the history of this site. We radiocarbon dated mortar samples selected from one of the Roman monuments (Westtor) as well as a nearby Medieval monastery. 14C ages obtained on the first fraction and second fraction of very short dissolution appear close to the expected Roman age of ∼2000 BP, while the monastery is dated to historic times, after AD 1308.
doi:10.1017/s0033822200047548 fatcat:hrefcpjbynfule5vxeyu4bbnu4

Liver function predicts survival in patients undergoing extracorporeal membrane oxygenation following cardiovascular surgery

Christian Roth, Lore Schrutka, Christina Binder, Lukas Kriechbaumer, Gottfried Heinz, Irene M. Lang, Gerald Maurer, Herbert Koinig, Barbara Steinlechner, Alexander Niessner, Klaus Distelmaier, Georg Goliasch
2016 Critical Care  
Extracorporeal membrane oxygenation (ECMO) represents a valuable and rapidly evolving therapeutic option in patients with severe heart or lung failure following cardiovascular surgery. However, despite significant advances in ECMO techniques and management, prognosis remains poor and accurate risk stratification challenging. We therefore evaluated the predictive value of liver function variables on all-cause mortality in patients undergoing venoarterial ECMO support after cardiovascular
more » ... Methods: We included into our single-center registry a total of 240 patients undergoing venoarterial ECMO therapy following cardiovascular surgery at a university-affiliated tertiary care center. Results: The median follow-up was 37 months (interquartile range 19-67 months), and a total of 156 patients (65 %) died. Alkaline phosphatase and total bilirubin were the strongest predictors for 30-day mortality, with adjusted hazard ratios (HRs) per 1-standard deviation increase of 1.36 (95 % confidence interval [CI] 1.10-1.68; P = 0.004) and 1.22 (95 % CI 1.07-1.40; P = 0.004), respectively. The observed associations persisted for long-term mortality, with adjusted HRs of 1.27 (95 % CI 1.03-1.56; P = 0.023) for alkaline phosphatase and 1.22 (95 % CI 1.07-1.39; P = 0.003) for total bilirubin. Conclusions: The present study demonstrates that elevated values of alkaline phosphatase and total bilirubin are sensitive parameters for predicting the short-term and long-term outcomes of ECMO patients.
doi:10.1186/s13054-016-1242-4 pmid:26968521 pmcid:PMC4788876 fatcat:xrobafptv5edlbluy6dkncty44

Exhaled Volatile Organic Compounds during Inflammation Induced by TNF-α in Ventilated Rats

Frederic W. Albrecht, Felix Maurer, Lukas M. Müller-Wirtz, Michaela H. Schwaiblmair, Tobias Hüppe, Beate Wolf, Daniel I. Sessler, Thomas Volk, Sascha Kreuer, Tobias Fink
2020 Metabolites  
Systemic inflammation alters the composition of exhaled breath, possibly helping clinicians diagnose conditions such as sepsis. We therefore evaluated changes in exhaled breath of rats given tumor necrosis factor-alpha (TNF-α). Thirty male Sprague-Dawley rats were randomly assigned to three groups (n = 10 each) with intravenous injections of normal saline (control), 200 µg·kg−1 bodyweight TNF-α (TNF-α-200), or 600 µg·kg−1 bodyweight TNF-α (TNF-α-600), and were observed for 24 h or until death.
more » ... nimals were ventilated with highly-purified synthetic air to analyze exhaled air by multicapillary column–ion mobility spectrometry. Volatile organic compounds (VOCs) were identified from a database. We recorded blood pressure and cardiac output, along with cytokine plasma concentrations. Control rats survived the 24 h observation period, whereas mean survival time decreased to 22 h for TNF-α-200 and 23 h for TNF-α-600 rats. Mean arterial pressure decreased in TNF-α groups, whereas IL-6 increased, consistent with mild to moderate inflammation. Hundreds of VOCs were detected in exhalome. P-cymol increased by a factor-of-two 4 h after injection of TNF-α-600 compared to the control and TNF-α-200. We found that 1-butanol and 1-pentanol increased in both TNF-α groups after 20 h compared to the control. As breath analysis distinguishes between two doses of TNF-α and none, we conclude that it might help clinicians identify systemic inflammation.
doi:10.3390/metabo10060245 pmid:32549262 fatcat:5gguhksbzzdm3p6uxoi7g6kcwm

Ultrafast resolution of tunneling delay time

Alexandra S. Landsman, Matthias Weger, Jochen Maurer, Robert Boge, André Ludwig, Sebastian Heuser, Claudio Cirelli, Lukas Gallmann, Ursula Keller
2014 Optica  
We compare the main competing theories of tunneling time against experimental measurements using the attoclock in strong laser field ionization of helium atoms. Refined attoclock measurements reveal a real and not instantaneous tunneling delay time over a large intensity regime, using two different experimental apparatus. Only two of the theoretical predictions are compatible within our experimental error: the Larmor time, and the probability distribution of tunneling times constructed using a
more » ... eynman Path Integral (FPI) formulation. The latter better matches the observed qualitative change in tunneling time over a wide intensity range, and predicts a broad tunneling time distribution with a long tail. The implication of such a probability distribution of tunneling times, as opposed to a distinct tunneling time, challenges how valence electron dynamics are currently reconstructed in attosecond science. It means that one must account for a significant uncertainty as to when the hole dynamics begin to evolve.
doi:10.1364/optica.1.000343 fatcat:cvgg4qdyevddjk7bjldobd6ima

First-principles calculations of hybrid inorganic–organic interfaces: from state-of-the-art to best practice

Oliver T. Hofmann, Egbert Zojer, Lukas Hörmann, Andreas Jeindl, Reinhard J. Maurer
2021 Physical Chemistry, Chemical Physics - PCCP  
A detailed review of these recent developments in materials research was recently given by Maurer et al. 175 The local density approximation (LDA) constitutes the 1 st rung of Perdew's ladder and is  ... 
doi:10.1039/d0cp06605b pmid:33875987 pmcid:PMC8237233 fatcat:dyc7ojieprewrbuwwlj56fbske

Quantification of Volatile Aldehydes Deriving from In Vitro Lipid Peroxidation in the Breath of Ventilated Patients

Lukas M. Müller-Wirtz, Daniel Kiefer, Sven Ruffing, Timo Brausch, Tobias Hüppe, Daniel I. Sessler, Thomas Volk, Tobias Fink, Sascha Kreuer, Felix Maurer
2021 Molecules  
Exhaled aliphatic aldehydes were proposed as non-invasive biomarkers to detect increased lipid peroxidation in various diseases. As a prelude to clinical application of the multicapillary column–ion mobility spectrometry for the evaluation of aldehyde exhalation, we, therefore: (1) identified the most abundant volatile aliphatic aldehydes originating from in vitro oxidation of various polyunsaturated fatty acids; (2) evaluated emittance of aldehydes from plastic parts of the breathing circuit;
more » ... 3) conducted a pilot study for in vivo quantification of exhaled aldehydes in mechanically ventilated patients. Pentanal, hexanal, heptanal, and nonanal were quantifiable in the headspace of oxidizing polyunsaturated fatty acids, with pentanal and hexanal predominating. Plastic parts of the breathing circuit emitted hexanal, octanal, nonanal, and decanal, whereby nonanal and decanal were ubiquitous and pentanal or heptanal not being detected. Only pentanal was quantifiable in breath of mechanically ventilated surgical patients with a mean exhaled concentration of 13 ± 5 ppb. An explorative analysis suggested that pentanal exhalation is associated with mechanical power—a measure for the invasiveness of mechanical ventilation. In conclusion, exhaled pentanal is a promising non-invasive biomarker for lipid peroxidation inducing pathologies, and should be evaluated in future clinical studies, particularly for detection of lung injury.
doi:10.3390/molecules26113089 pmid:34064214 fatcat:564o5xak3jhtlmkv7vh2yot7va
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