@article{VincentKenfackSenthilkumaretal.2010, author = {Vincent, Uchechukwu E. and Kenfack, Anatole and Senthilkumar, Dharmapuri Vijayan and Mayer, Dieter and Kurths, J{\"u}rgen}, title = {Current reversals and synchronization in coupled ratchets}, issn = {1539-3755}, doi = {10.1103/Physreve.82.046208}, year = {2010}, abstract = {Current reversal is an intriguing phenomenon that has been central to recent experimental and theoretical investigations of transport based on ratchet mechanism. By considering a system of two interacting ratchets, we demonstrate how the coupling can be used to control the reversals. In particular, we find that current reversal that exists in a single driven ratchet system can ultimately be eliminated with the presence of a second ratchet. For specific coupling strengths a current-reversal free regime has been detected. Furthermore, in the fully synchronized state characterized by the coupling threshold k(th), a specific driving amplitude a(opt) is found for which the transport is optimum.}, language = {en} } @article{ShekharReimannMayeretal.2021, author = {Shekhar, Sumit and Reimann, Max and Mayer, Maximilian and Semmo, Amir and Pasewaldt, Sebastian and D{\"o}llner, J{\"u}rgen and Trapp, Matthias}, title = {Interactive photo editing on smartphones via intrinsic decomposition}, series = {Computer graphics forum : journal of the European Association for Computer Graphics}, volume = {40}, journal = {Computer graphics forum : journal of the European Association for Computer Graphics}, publisher = {Blackwell}, address = {Oxford}, issn = {0167-7055}, doi = {10.1111/cgf.142650}, pages = {497 -- 510}, year = {2021}, abstract = {Intrinsic decomposition refers to the problem of estimating scene characteristics, such as albedo and shading, when one view or multiple views of a scene are provided. The inverse problem setting, where multiple unknowns are solved given a single known pixel-value, is highly under-constrained. When provided with correlating image and depth data, intrinsic scene decomposition can be facilitated using depth-based priors, which nowadays is easy to acquire with high-end smartphones by utilizing their depth sensors. In this work, we present a system for intrinsic decomposition of RGB-D images on smartphones and the algorithmic as well as design choices therein. Unlike state-of-the-art methods that assume only diffuse reflectance, we consider both diffuse and specular pixels. For this purpose, we present a novel specularity extraction algorithm based on a multi-scale intensity decomposition and chroma inpainting. At this, the diffuse component is further decomposed into albedo and shading components. We use an inertial proximal algorithm for non-convex optimization (iPiano) to ensure albedo sparsity. Our GPU-based visual processing is implemented on iOS via the Metal API and enables interactive performance on an iPhone 11 Pro. Further, a qualitative evaluation shows that we are able to obtain high-quality outputs. Furthermore, our proposed approach for specularity removal outperforms state-of-the-art approaches for real-world images, while our albedo and shading layer decomposition is faster than the prior work at a comparable output quality. Manifold applications such as recoloring, retexturing, relighting, appearance editing, and stylization are shown, each using the intrinsic layers obtained with our method and/or the corresponding depth data.}, language = {en} } @article{ScharhagRosenbergerWochatzOttoetal.2014, author = {Scharhag-Rosenberger, Friederike and Wochatz, Monique and Otto, Christoph and Cassel, Michael and Mayer, Frank and Scharhag, J{\"u}rgen}, title = {Blood lactate concentrations are mildly affected by mobile gas exchange measurements}, series = {International journal of sports medicine}, volume = {35}, journal = {International journal of sports medicine}, number = {7}, publisher = {Thieme}, address = {Stuttgart}, issn = {0172-4622}, doi = {10.1055/s-0033-1354386}, pages = {590 -- 594}, year = {2014}, abstract = {We sought to investigate the effects of wearing a mobile respiratory gas analysis system during a treadmill test on blood lactate (bLa) concentrations and commonly applied bLa thresholds. A total of 16 recreational athletes (31 +/- 3 years, V0205: 58 6 ml min(-1)-kg(-1)) performed one multistage treadmill test with and one without gas exchange measurements (GEM and noGEM). The whole bLa curve, the lactate threshold (LT), the individual anaerobic thresholds according to Stegmann(IAT(sr)) and Dickhuth (IAT(Di)), and a fixed bLa concentration of 4 mmob.l(-1) (OBLA) were evaluated. The bLa curve was shifted slightly leftward in GEM compared to noGEM (P<0.05), whereas the heart rate response was not different between conditions (P= 0.89). There was no difference between GEM and noGEM for LT (2.61 +/- 0.34 vs. 2.64 +/- 0.39 m(-1) s(-1) P=0.49) and IAT(st) (3.47 +/- 0.42 vs. 3.55 +/- 0.47m-s(-1), P=0.12). However, IATD(Di) (3.57 +/- 0.39 vs. 3.66 +/- 0.44m-s(-1), P<0.01) and OBLA (3.85 +/- 0.46 vs. 3.96 +/- 0.47m-s-1, P<0.01) occurred at slower running velocities in GEM. The bLa response to treadmill tests is mildly affected by wearing a mobile gas analysis system. This also applies to bLa thresholds located at higher exercise intensities. While the magnitude of the effects is of little importance for recreational athletes, it might be relevant for elite athletes and scientific studies.}, language = {en} } @inproceedings{ScharhagRosenbergerCarlsohnSchueleretal.2012, author = {Scharhag-Rosenberger, Friederike and Carlsohn, Anja and Sch{\"u}ler, Stefan and Lundby, Carsten and Mayer, Frank and Scharhag, J{\"u}rgen}, title = {Physiological changes over four maximal incremental cycling tests within one day}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {44}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {933 -- 934}, year = {2012}, language = {en} } @article{ScharhagRosenbergerCarlsohnLundbyetal.2014, author = {Scharhag-Rosenberger, Friederike and Carlsohn, Anja and Lundby, Carsten and Schueler, Stefan and Mayer, Frank and Scharhag, J{\"u}rgen}, title = {Can more than one incremental cycling test be performed within one day?}, series = {European journal of sport science : official journal of the European College of Sport Science}, volume = {14}, journal = {European journal of sport science : official journal of the European College of Sport Science}, number = {5}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {1746-1391}, doi = {10.1080/17461391.2013.853208}, pages = {459 -- 467}, year = {2014}, abstract = {Changes in performance parameters over four consecutive maximal incremental cycling tests were investigated to determine how many tests can be performed within one single day without negatively affecting performance. Sixteen male and female subjects (eight trained (T): 25 +/- 3 yr, BMI 22.6 +/- 2.5 kg center dot m(-2), maximal power output (P-max) 4.6 +/- 0.5 W center dot kg(-1); eight untrained (UT): 27 +/- 3 yr, BMI 22.3 +/- 1.2 kg center dot m(-2), P-max 2.9 +/- 0.3 W center dot kg(-1)) performed four successive maximal incremental cycling tests separated by 1.5 h of passive rest. Individual energy requirements were covered by standardised meals between trials. Maximal oxygen uptake (VO2max) remained unchanged over the four tests in both groups (P = 0.20 and P = 0.33, respectively). P-max did not change in the T group (P = 0.32), but decreased from the third test in the UT group (P < 0.01). Heart rate responses to submaximal exercise were elevated from the third test in the T group and from the second test in the UT group (P < 0.05). The increase in blood lactate shifted rightward over the four tests in both groups (P < 0.001 and P < 0.01, respectively). Exercise-induced net increases in epinephrine and norepinephrine were not different between the tests in either group (P 0.15). If VO2max is the main parameter of interest, trained and untrained individuals can perform at least four maximal incremental cycling tests per day. However, because other parameters changed after the first and second test, respectively, no more than one test per day should be performed if parameters other than VO2max are the prime focus.}, language = {en} } @article{ScharhagRosenbergerCarlsohnCasseletal.2011, author = {Scharhag-Rosenberger, Friederike and Carlsohn, Anja and Cassel, Michael and Mayer, Frank and Scharhag, J{\"u}rgen}, title = {How to test maximal oxygen uptake a study on timing and testing procedure of a supramaximal verification test}, series = {Applied physiology, nutrition, and metabolism = Physiologie appliqu{\´e}e, nutrition et m{\´e}tabolisme}, volume = {36}, journal = {Applied physiology, nutrition, and metabolism = Physiologie appliqu{\´e}e, nutrition et m{\´e}tabolisme}, number = {1}, publisher = {NRC Research Press}, address = {Ottawa}, issn = {1715-5312}, doi = {10.1139/H10-099}, pages = {153 -- 160}, year = {2011}, abstract = {On utilise de plus en plus les tests de verification pour confirmer l'atteinte du consommation d'oxygene maximale (VO(2 max)). Toutefois, le moment et les methodes d'evaluation varient d'un groupe de travail a l'autre. Les objectifs de cette etude sont de constater si on peut administrer un test de verification apres un test d'effort progressif ou s'il est preferable de le faire une autre journee et si on peut determiner le VO(2 max) tout de meme lors de la premiere seance chez des sujets ne repondant pas au critere de verification. Quarante sujets (age, 24 +/- 4 ans; VO(2 max), 50 +/- 7 mL center dot min(-1)center dot kg(-1)) participent a un test d'effort progressif sur tapis roulant et, 10 min plus tard, a un test de verification (VerifDay1) a 110 \% de la velocite maximale (v(max)). Le critere de verification est un VO(2) de pointe au VerifDay1 < 5,5 \% a la valeur retenue au test d'effort progressif. Les sujets ne repondant pas au critere de verification passent un autre test de verification, mais a 115 \% du VerifDay1', et ce, 10 min plus tard pour confirmer le VO(2) de pointe du VerifDay1 en tant que VO(2 max). Tous les autres sujets repassent le VerifDay1 a un jour different (VerifDay2). Six sujets sur quarante ne repondent pas au critere de verification. Chez quatre d'entre eux, on confirme l'atteinte du VO(2 max) au VerifDay1'. Le VO(2) de pointe au VerifDay1 est equivalent a celui du VerifDay2 (3722 +/- 991 mL center dot min(-1) comparativement a 3752 +/- 995 mL center dot min(-1), p = 0,56), mais le temps jusqu'a l'epuisement est significativement plus long au VerifDay2 (2:06 +/- 0:22 min:s comparativement a 2:42 +/- 0:38 min:s, p < 0,001, n = 34). Le VO(2) de pointe obtenu au test de verification ne semble pas conditionne par un test d'effort progressif maximal prealable. On peut donc realiser le test d'effort progressif et le test de verification lors de la meme seance d'evaluation. Chez presque tous les individus ne repondant pas au critere de verification, on peut determiner le VO(2 max) au moyen d'un autre test de verification plus intense.}, language = {en} } @misc{ScharhagKnebelMayeretal.2011, author = {Scharhag, J{\"u}rgen and Knebel, F. and Mayer, Frank and Kindermann, Wilfried}, title = {Does marathon running damage the heart? - an update}, series = {Deutsche Zeitschrift f{\"u}r Sportmedizin : offizielles Organ der Deutschen Gesellschaft f{\"u}r Sportmedizin und Pr{\"a}vention (Deutscher Sport{\"a}rztebund) e.V. (DGSP) und Weiterbildungsorgan der {\"O}sterreichischen Gesellschaft f{\"u}r Sportmedizin und Pr{\"a}vention}, volume = {62}, journal = {Deutsche Zeitschrift f{\"u}r Sportmedizin : offizielles Organ der Deutschen Gesellschaft f{\"u}r Sportmedizin und Pr{\"a}vention (Deutscher Sport{\"a}rztebund) e.V. (DGSP) und Weiterbildungsorgan der {\"O}sterreichischen Gesellschaft f{\"u}r Sportmedizin und Pr{\"a}vention}, number = {9}, publisher = {WWF-Verl.-Ges.}, address = {Greven}, issn = {0344-5925}, pages = {293 -- 298}, year = {2011}, abstract = {Since the legend of the ancient Marathon run, the risk of endurance exercise-induced cardiovascular damage or sudden cardiac death is discussed. In recent studies, the exercise-induced increases in cardiac biomarkers in endurance athletes as well as acute alterations in cardiac function and cardiovascular abnormalities have been reported. As elevations of the cardiac biomarkers troponin and BM) have been observed frequently for the vast majority of athletes after Marathon runs or strenuous exercise bouts followed by a decrease within a short period, a physiological reaction rather than a pathologicial cause is presumed. Also a transient decrease of cardiac function demonstrated by newer echocardiographic techniques (tissue Doppler or speckle tracking imaging, 3D echocardiography) after strenuous exercise often termed "cardiac fatigue" should not be considered necessarily as pathologic, as cardiac function also depends on hemodynamic load and heart rate. Furthermore, exercise-induced changes in cardiac function did not correlate with exercise-induced increases in cardiac biomarkers in most studies. The functional cardiac alterations can also be detected by magnetic resonance imaging (MRI) after Marathon runs. However, no signs of acute or chronic myocardial damage have been demonstrated in MRI studies in cardiovascular healthy athletes after running a Marathon, although especially in older athletes undetected cardiovascular diseases such as coronary artery disease or myocardial necrosis or fibrosis can be present. hi conclusion, according to recent studies. there seems to be a lack of evidence to support endurance exercise-induced cardiac damage in the healthy heart which is adapted tostrenous exercise by regular endurance training. Nevertheless, as running a Marathon results in a high cardiac load, a sufficient endurance training period as well as a preparticipation or regular medical screening to exclude relevant congenital or aquired cardiovascular diseases is recommended from a sports cardiology perspective to exclude relevant congenital or acquired cardiovascular diseases}, language = {de} } @inproceedings{ScharhagHotzkowKopinskietal.2012, author = {Scharhag, J{\"u}rgen and Hotzkow, Kristin and Kopinski, Stephan and Barche, Martin and Mayer, Frank}, title = {Echocardiographic 3d speckle tracking values on cardiac wall motion in elite adult, adolescent and pediatric athletes}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {44}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {241 -- 241}, year = {2012}, language = {en} } @inproceedings{OttoScharhagRosenbergerCarlsohnetal.2012, author = {Otto, Christoph and Scharhag-Rosenberger, Friederike and Carlsohn, Anja and Scharhag, J{\"u}rgen and Mayer, Frank}, title = {Differences in using the same supramaximal verification test protocol for treadmill and cycle ergometry}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {44}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {295 -- 295}, year = {2012}, language = {en} } @article{MeierGrospietschMayer2018, author = {Meier, Monique and Grospietsch, Finja and Mayer, J{\"u}rgen}, title = {Vernetzung von Wissensfacetten professioneller Handlungskompetenz in hochschuldidaktischen Lehr-Lernsettings}, series = {Koh{\"a}renz in der universit{\"a}ren Lehrerbildung}, journal = {Koh{\"a}renz in der universit{\"a}ren Lehrerbildung}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, isbn = {978-3-86956-438-8}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-418558}, pages = {143 -- 178}, year = {2018}, language = {de} }