35 results on '"Thein, J."'
Search Results
2. Some like it hot? Developmental differences in Yellow-bellied Toad (Bombina variegata) tadpoles from geographically close but different habitats
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Dittrich, C., DrakuliC, S., Schellenberg, M., Thein, J., and Rodel, M.-O.
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Tadpoles -- Physiological aspects -- Environmental aspects ,Habitat (Ecology) -- Physiological aspects ,Animal development -- Environmental aspects ,Zoology and wildlife conservation - Abstract
The key for the long-term survival of species is their potential to respond to changing conditions. These reactions are usually species-specific and may vary between populations. The Yellow-bellied Toad (Bombina variegata (L., 1758)) occurs in forested and open areas. We wanted to know whether tadpoles react plastically to different environmental conditions, and if so, whether reaction norms are species, population, or season specific. In a common garden experiment, we compared developmental traits (developmental time, size, body condition) of metamorphs from different habitats (forest vs. quarry) in close geographic proximity. Tadpoles from both habitats grew up under shaded and sunny conditions. The experiments were run during early and late breeding season. We detected different developmental strategies between populations, concerning treatments and season on a microgeographic scale. Tadpoles with quarry origin developed faster and reached larger body sizes, at the expense of lower body condition. Major risks affecting tadpole's survival in the open habitat are high temperatures and high desiccation. Forest tadpoles were comparatively smaller in size, but showed higher plasticity and higher body condition. Under changing climatic conditions, quarry population may reach temperatures above their thermal limits. In contrast, forest conditions may mitigate increasing temperatures. Forest populations could be better adapted to future climate change. Key words: adaptation, plasticity, developmental traits, seasonality, climate change. La cle de la survie a long terme d'une espece reside dans sa capacite de reagir a des conditions changeantes. Ces reactions different normalement selon l'espece et pourraient varier selon la population. Le sonneur a ventre jaune (Bombina variegata (L., 1758)) occupe des zones boisees et ouvertes. Nous voulions savoir si les tetards reagissent de maniere plastique a differentes conditions ambiantes et, le cas echeant, si les normes de reaction varient selon l'espece, la population ou la saison. Dans une experience de jardin commun, nous avons compare des caracteres du developpement (temps de developpement, taille, embonpoint) de metamorphes issus d'habitats differents (foret contre carriere) tres rapproches dans l'espace. Les tetards des deux habitats ont grandi dans des conditions ombragees et ensoleillees. Les experiences ont ete menees au debut et a la fin de la periode de reproduction. Nous avons decele differentes strategies de developpement selon la population en fonction du traitement et de la saison, a une echelle microgeographique. Les tetards provenant de la carriere se developpaient plus rapidement et atteignaient des tailles du corps plus grandes, au detriment de l'embonpoint, qui etait plus faible. Les principaux risques pour la survie des tetards dans l'habitat ouvert sont les temperatures elevees et une forte dessication. Les tetards issus du milieu boise etaient de taille plus faible, mais presentaient une plus grande plasticite et un meilleur embonpoint. Dans des conditions climatiques changeantes, les individus de la population de la carriere pourraient atteindre des temperatures superieures a leurs temperatures limites. En revanche, les conditions propres aux milieux boises pourraient attenuer l'effet du rechauffement. Les populations de forets pourraient etre mieux adaptees aux changements climatiques a venir. [Traduit par la Redaction] Mots-cles: adaptation, plasticite, caracteres du developpement, saisonnalite, changement climatique., Introduction Species have three principal options to survive changing environmental conditions: (1) react plastically to the change; (2) evolve adjusted new characters (e.g., concerning physiology or behaviour); or (3) migrate [...]
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- 2016
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3. Problems and approaches related to the cleaning and safe storage of preparation residues from uranium ore mining in eastern Germany
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Thein, J., Hähne, R., Klapperich, H., Groß, U., Arendt, F., editor, Annokkée, G. J., editor, Bosman, R., editor, and Van Den Brink, W. J., editor
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- 1993
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4. Die Grabung des Jahres 1976 auf dem Münsterplatz in Neuss
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Härke, Heinrich, Knörzer, Karl-Heinz, Reichstein, Hans, Thein, J., Watermann, R., and Zedelius, Volker
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Bonner Jahrbücher, Bd. 180.1980: Bonner Jahrbücher
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- 2020
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5. Catastrophic soil loss associated with end-Triassic deforestation
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Marine palynology and palaeoceanography, Marine Palynology, van de Schootbrugge, B., van der Weijst, C. M.H., Hollaar, T. P., Vecoli, M., Strother, P. K., Kuhlmann, N., Thein, J., Visscher, H., van Konijnenburg-van Cittert, H., Schobben, M. A.N., Sluijs, A., Lindström, S., Marine palynology and palaeoceanography, Marine Palynology, van de Schootbrugge, B., van der Weijst, C. M.H., Hollaar, T. P., Vecoli, M., Strother, P. K., Kuhlmann, N., Thein, J., Visscher, H., van Konijnenburg-van Cittert, H., Schobben, M. A.N., Sluijs, A., and Lindström, S.
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- 2020
6. Energetics of calling and metabolic substrate use during prolonged exercise in the European treefrog Hyla arborea
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Grafe, T. U. and Thein, J.
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- 2001
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7. Sedimentation in the Atlas Gulf III: Turonian Carbonates
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Stamm, Roger, Thein, J., von Rad, Ulrich, editor, Hinz, Karl, editor, Sarnthein, Michael, editor, and Seibold, Eugen, editor
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- 1982
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8. SITE-613
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Poag, C, Watts, A, Cousin, M, Goldberg, D, Hart, D, Miller, K, Mountain, G, Nakamura, Y, Palmer, A, Schiffelbein, P, Tarafa, M, Thein, J, Valentine, P, and Wilkins, R
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The general composition of the lithologic units at Site DSDP 613 varies only slightly from those at Site 612, but the style of decomposition is significantly different. Whereas evenbedded hemipelagic deposition prevailed most of the time at Site 612, the section at Site 613 is characterized by the frequent occurrence of slump deposits and conglomeratic, sandy, channel-fill deposits.- from Authors
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- 2016
9. Sedimentationsabläufe im Atlas-Golf (Kreide Küstenbecken Marokko)
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Behrens, M., Krumsiek, K., Meyer, D. E., Schäfer, Essen, A., Siehl, A., Stets, J., Thein, J., and Wurster, P.
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- 1978
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10. Silica Diagenesis in Continental Slope and Rise Sediments off Eastern North America (Sites 603 and 605, Leg 93; Sites 612 and 613, Leg 95)
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Thein, J., primary and von Rad, U., additional
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- 1987
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11. Lithologic and Geochemical Changes across Unconformities at Site 612, Deep Sea Drilling Project Leg 95, New Jersey Transect
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Cousin, M., primary and Thein, J., additional
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- 1987
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12. A Tektite Layer in Upper Eocene Sediments of the New Jersey Continental Slope (Site 612, Leg 95)
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Thein, J., primary
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- 1987
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13. Environmental factors fail to explain oviposition site use in the European common frog
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Grözinger, F., primary, Wertz, A., additional, Thein, J., additional, Feldhaar, H., additional, and Rödel, M.-O., additional
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- 2012
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14. Analysing and modelling solute and sediment transport in the catchment of the Wahnbach River
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Bogena, H., primary, Diekkrüger, B., additional, Klingel, K., additional, Jantos, K., additional, and Thein, J., additional
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- 2003
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15. Visualization tool for a terrain-based genetic algorithm.
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Gordon, V.S. and Thein, J.
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- 2004
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16. Abfallbeseitigung in Bergbaugebieten: Altstandorte und Altlasten. Sicherung oder Sanierung? Ein Fallbeispiel aus dem Mansfelder Land
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Dörhöfer, G., Thein, J., Wigering, H., Gläser, Hans-Reinhard, Gläßer, Walter, Jacob, G., Weiß, Holger, Dörhöfer, G., Thein, J., Wigering, H., Gläser, Hans-Reinhard, Gläßer, Walter, Jacob, G., and Weiß, Holger
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- 1993
17. SITE-613
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POAG, C, WATTS, A, COUSIN, M, GOLDBERG, D, HART, D, MILLER, K, MOUNTAIN, G, NAKAMURA, Y, PALMER, A, SCHIFFELBEIN, P, TARAFA, M, THEIN, J, VALENTINE, P, and WILKINS, R
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The general composition of the lithologic units at Site DSDP 613 varies only slightly from those at Site 612, but the style of decomposition is significantly different. Whereas evenbedded hemipelagic deposition prevailed most of the time at Site 612, the section at Site 613 is characterized by the frequent occurrence of slump deposits and conglomeratic, sandy, channel-fill deposits.- from Authors
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- 1987
18. Palaeogeography and geochemistry of the 'Cenomano-Turonian' Formations in the manganese district of Imini (Morocco) and their relation to ore deposition.
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Thein J. and Thein J.
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Regional distribution and stratigraphic setting of manganese and the associated metals suggest that the ores were formed in a zone of mixing between oxidised groundwater of meteoric origin and reducing seawater near the coast. The ore-forming metals were provided by continental weathering solutions and by remobilisation processes in anoxic deep ocean basins. Giant stratiform manganese deposits of the Imini-type are formed in periods of high sea-level, warm climate and global anoxic conditions in the oceans., Regional distribution and stratigraphic setting of manganese and the associated metals suggest that the ores were formed in a zone of mixing between oxidised groundwater of meteoric origin and reducing seawater near the coast. The ore-forming metals were provided by continental weathering solutions and by remobilisation processes in anoxic deep ocean basins. Giant stratiform manganese deposits of the Imini-type are formed in periods of high sea-level, warm climate and global anoxic conditions in the oceans.
19. Geochemistry and origin of the stratiform sulphide ore deposit of Meggen (Middle Devonian, Rheinisches Schiefergebirge).
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Thein J. and Thein J.
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The deposit is in the upper Middle Devonian clastic and carbonate rocks of the Elspe syncline. A central sulphide lens is surrounded by a ring of barite. In the sulphide ore, the concentrations of S, Fe, Zn, Pb, As, Ba, Cd, Co, Cu, Mn, Ni, Sb and Tl vary with their stratigraphic and topographic position in the deposit and the palaoageographic configuration of the ore is mirrored in the concentric pattern of these concentrations around the deposit. Geochemical trends in the strata are independent of the structure of the orebody. Pronounced analogies in the geochemical and mineralogical composition, as well as in the structure of the orebody, suggest that the Meggen ore was formed in similar a way to the recent deposits of hot brines in the Red Sea., The deposit is in the upper Middle Devonian clastic and carbonate rocks of the Elspe syncline. A central sulphide lens is surrounded by a ring of barite. In the sulphide ore, the concentrations of S, Fe, Zn, Pb, As, Ba, Cd, Co, Cu, Mn, Ni, Sb and Tl vary with their stratigraphic and topographic position in the deposit and the palaoageographic configuration of the ore is mirrored in the concentric pattern of these concentrations around the deposit. Geochemical trends in the strata are independent of the structure of the orebody. Pronounced analogies in the geochemical and mineralogical composition, as well as in the structure of the orebody, suggest that the Meggen ore was formed in similar a way to the recent deposits of hot brines in the Red Sea.
20. Minette-type ironstones
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Siehl, A., primary and Thein, J., additional
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- 1989
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21. Visualization tool for a terrain-based genetic algorithm
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Gordon, V.S., primary and Thein, J., additional
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22. Enhancing Attentional Performance in Parkinson's Disease: The Impact of Combined Deep Brain Stimulation of the Substantia Nigra Pars Reticulata and the Subthalamic Nucleus.
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Thein J, Linnhoff S, Voges J, Galazky I, and Zaehle T
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- Humans, Male, Middle Aged, Female, Aged, Pars Reticulata physiopathology, Parkinson Disease therapy, Parkinson Disease physiopathology, Parkinson Disease complications, Deep Brain Stimulation methods, Subthalamic Nucleus physiopathology, Attention physiology, Reaction Time physiology
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Objective: The concomitant stimulation of the subthalamic nucleus and the substantia nigra pars reticulata is a promising approach to improve treatment of refractory axial symptoms in Parkinson's disease. While dual stimulation of the subthalamic nucleus and the substantia nigra pars reticulata has previously shown beneficial effects on gait, the role of the substantia nigra, a crucial component of the basal ganglia circuitry, in cognitive functions such as attention and executive control remains underexplored. This study aimed to investigate the impact of selective substantia nigra pars reticulata stimulation on attentional performance in patients receiving standard deep brain stimulation of the subthalamic nucleus., Methods: Twelve patients with bilateral subthalamic nucleus stimulation underwent computerized assessment of attention using a simple reaction time task. Reaction times were assessed under standard stimulation of the subthalamic nucleus versus simultaneous stimulation of the subthalamic nucleus and the substantia nigra pars reticulata., Results: The results revealed a significant improvement in reaction times during the simple reaction time task when patients received dual stimulation compared to standard stimulation., Conclusions: Our findings provide further evidence for the pivotal role of the substantia nigra pars reticulata in cognitive functions such as attention. Despite the limitations of the study, including a small sample size, our results suggest potential benefits of simultaneous deep brain stimulation of the subthalamic nucleus and the substantia nigra pars reticulata on attentional performance in patients with Parkinson's disease. Further research with larger cohorts is warranted to confirm these findings and better understand the underlying mechanisms., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2024
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23. Suprazygomatic Maxillary Nerve Blocks and Opioid Requirements in Pediatric Adenotonsillectomy: A Randomized Clinical Trial.
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Lin C, Abboud S, Zoghbi V, Kasimova K, Thein J, Meister KD, Sidell DR, Balakrishnan K, and Tsui BCH
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- Humans, Child, Male, Female, Child, Preschool, Prospective Studies, Adolescent, Pain Measurement, Tonsillectomy methods, Adenoidectomy methods, Analgesics, Opioid therapeutic use, Analgesics, Opioid administration & dosage, Pain, Postoperative drug therapy, Pain, Postoperative prevention & control, Nerve Block methods
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Importance: Pain management following pediatric adenotonsillectomies is opioid-inclusive, leading to potential complications., Objective: To investigate the use of suprazygomatic maxillary nerve (SZMN) blocks to reduce pain and opioid use after pediatric intracapsular adenotonsillectomy and to measure recovery duration and incidence of complications., Design, Setting, and Participants: This was a randomized, blinded, prospective single-center tertiary pediatric hospital that included 60 pediatric patients (2-14 years old) scheduled for intracapsular adenotonsillectomy from November 2021 to March 2023. Patients were excluded for having combined surgical procedures, developmental delay, coagulopathy, chronic pain history, known or predicted difficult airway, or unrepaired congenital heart disease. Participants were randomized to receive bilateral SZMN blocks (block group) or not (control group)., Intervention: SZMN block administered bilaterally under general anesthesia for intracapsular adenotonsillectomy., Primary Outcomes and Measures: Opioid consumption, FLACC (Face, Legs, Activity, Cry, Consolability) scores, and rates of opioid-free postanesthesia care unit (PACU) stay. Secondary outcomes were recovery duration and incidence of adverse effects, ie, nausea, vomiting, block site bleeding, and emergency delirium., Results: The study population included 53 pediatric patients (mean [SD] age, 6.5 [3.6] years; 29 [55%] females; 24 [45%] males); 26 were randomly assigned to the SZMN block group and 27 to the control group. The mean (SD) opioid morphine equivalent consumption during PACU stay was 0.15 (0.14) mg/kg for the 27 patients in the control group compared with 0.07 (0.11) mg/kg for the 26 patients in the block group (mean difference, 0.08; 95% CI, 0.01-0.15; Cohen d, 0.64). The block group had a higher incidence of opioid-free PACU stays (n = 7 patients; 58%) compared with the control group (n = 15 patients; 26%) (mean difference, 32%; 95% CI, 5%-53%). Patients in the block group experienced lower FLACC scores (0.7 vs 1.6; mean difference, 0.9; 95% CI, 0.2-1.6; Cohen d, 0.7). The overall occurrence of adverse events was similar in the 2 groups, with no reported nerve block-related complications., Conclusions and Relevance: The results of the randomized clinical trial indicate that SZMN blocks are a useful adjunct tool for managing postoperative pain in pediatric intracapsular adenotonsillectomy. Use of these blocks during adenotonsillectomy provided clinically meaningful reductions of postoperative opioid consumption with a low risk of complications., Trial Registration: ClinicalTrials.gov Identifier: NCT04797559.
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- 2024
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24. Alpine salamanders at risk? The current status of an emerging fungal pathogen.
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Böning P, Lötters S, Barzaghi B, Bock M, Bok B, Bonato L, Ficetola GF, Glaser F, Griese J, Grabher M, Leroux C, Munimanda G, Manenti R, Ludwig G, Preininger D, Rödel MO, Seibold S, Smith S, Tiemann L, Thein J, Veith M, and Plewnia A
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- Animals, Communicable Diseases, Emerging microbiology, Communicable Diseases, Emerging epidemiology, Communicable Diseases, Emerging veterinary, Salamandra microbiology, Europe epidemiology, Chytridiomycota, Batrachochytrium genetics, Batrachochytrium pathogenicity, Mycoses veterinary, Mycoses microbiology, Mycoses epidemiology, Urodela microbiology
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Amphibians globally suffer from emerging infectious diseases like chytridiomycosis caused by the continuously spreading chytrid fungi. One is Batrachochytrium salamandrivorans (Bsal) and its disease ‒ the 'salamander plague' ‒ which is lethal to several caudate taxa. Recently introduced into Western Europe, long distance dispersal of Bsal, likely through human mediation, has been reported. Herein we study if Alpine salamanders (Salamandra atra and S. lanzai) are yet affected by the salamander plague in the wild. Members of the genus Salamandra are highly susceptible to Bsal leading to the lethal disease. Moreover, ecological modelling has shown that the Alps and Dinarides, where Alpine salamanders occur, are generally suitable for Bsal. We analysed skin swabs of 818 individuals of Alpine salamanders and syntopic amphibians at 40 sites between 2017 to 2022. Further, we compiled those with published data from 319 individuals from 13 sites concluding that Bsal infections were not detected. Our results suggest that the salamander plague so far is absent from the geographic ranges of Alpine salamanders. That means that there is still a chance to timely implement surveillance strategies. Among others, we recommend prevention measures, citizen science approaches, and ex situ conservation breeding of endemic salamandrid lineages., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Böning et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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25. Temperature preferences drive additive biotic homogenization of Orthoptera assemblages.
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Thorn S, König S, Fischer-Leipold O, Gombert J, Griese J, and Thein J
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- Animals, Biodiversity, Ecosystem, Temperature, Grassland, Orthoptera
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The degradation of natural habitats is causing ongoing homogenization of biological communities and declines in terrestrial insect biodiversity, particularly in agricultural landscapes. Orthoptera are focal species of nature conservation and experienced significant diversity losses over the past decades. However, the causes underlying these changes are not yet fully understood. We analysed changes in Orthoptera assemblages surveyed in 1988, 2004 and 2019 on 198 plots distributed across four major grassland types in Central Europe. We demonstrated compositional differences in Orthoptera assemblages found in wet, dry and mesic grasslands, as well as ruderal habitats decreased, indicating biotic homogenization. However, mean α-diversity of Orthoptera assemblages increased over the study period. We detected increasing numbers of species with preferences for higher temperatures in mesic and wet grasslands. By analysing the temperature, moisture and vegetation preferences of Orthoptera, we found that additive homogenization was driven by a loss of species adapted to extremely dry and nitrogen-poor habitats and a parallel spread of species preferring warmer macroclimates.
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- 2022
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26. The Effect of Kalman-Weighted Averaging and Artifact Rejection on Residual Noise During Auditory Brainstem Response Testing.
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Norrix LW, Thein J, and Velenovsky D
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- Adult, Female, Healthy Volunteers, Humans, Male, Young Adult, Artifacts, Electroencephalography methods, Evoked Potentials, Auditory, Brain Stem, Hearing Tests methods, Noise
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Purpose Low residual noise (RN) levels are critically important when obtaining electrophysiological recordings of threshold auditory brainstem responses. In this study, we examine the effectiveness and efficiency of Kalman-weighted averaging (KWA) implemented on the Vivosonic Integrity System and artifact rejection (AR) implemented on the Intelligent Hearing Systems SmartEP system for obtaining low RN levels. Method Sixteen adults participated. Electrophysiological measures were obtained using simultaneous recordings by the Vivosonic and Intelligent Hearing Systems for subjects in 2 relaxed conditions and 4 active motor conditions. Three averaging times were used for the relaxed states (1, 1.5, and 3 min) and for the active states (1.5, 3, and 6 min). Repeated-measures analyses of variance were used to examine RN levels as a function of noise reduction strategy (i.e., KWA, AR) and averaging time. Results Lower RN levels were obtained using KWA than AR in both the relaxed and active motor states. Thus, KWA was more effective than was AR under the conditions examined in this study. Using KWA, approximately 3 min of averaging was needed in the relaxed condition to obtain an average RN level of 0.025 μV. In contrast, in the active motor conditions, approximately 6 min of averaging was required using KWA. Mean RN levels of 0.025 μV were not attained using AR. Conclusions When patients are not physiologically quiet, low RN levels are more likely to be obtained and more efficiently obtained using KWA than AR. However, even when using KWA, in active motor states, 6 min of averaging or more may be required to obtain threshold responses. Averaging time needed and whether a low RN level can be attained will depend on the level of motor activity exhibited by the patient.
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- 2019
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27. Exciton-Vibrational Couplings in Homo- and Heterodimer Stacks of Perylene Bisimide Dyes within Cyclophanes: Studies on Absorption Properties and Theoretical Analysis.
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Bialas D, Brüning C, Schlosser F, Fimmel B, Thein J, Engel V, and Würthner F
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The optical properties of a series of three cyclophanes comprising either identical or different perylene bisimide (PBI) chromophores were studied by UV/Vis absorption spectroscopy and their distinctive spectral features were analyzed. All the investigated cyclophanes show significantly different absorption features with respect to the corresponding constituent PBI monomers indicating strong coupling interactions between the PBI units within the cyclophanes. DFT calculations suggest a π-stacked arrangement of the PBI units at close van der Waals distance in the cyclophanes with rotational displacement. Simulations of the absorption spectra based on time-dependent quantum mechanics properly reproduced the experimental spectra, revealing exciton-vibrational coupling between the chromophores both in homo- and heterodimer stacks. The PBI cyclophane comprising two different PBI chromophores represents the first example of a PBI heterodimer stack for which the exciton coupling has been investigated. The quantum dynamics analysis reveals that exciton coupling in heteroaggregates is indeed of similar strength as for homoaggregates., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
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- 2016
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28. Impact of Alkyl Spacer Length on Aggregation Pathways in Kinetically Controlled Supramolecular Polymerization.
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Ogi S, Stepanenko V, Thein J, and Würthner F
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We have investigated the kinetic and thermodynamic supramolecular polymerizations of a series of amide-functionalized perylene bisimide (PBI) organogelator molecules bearing alkyl spacers of varied lengths (ethylene to pentylene chains, PBI-1-C2 to PBI-1-C5) between the amide and PBI imide groups. These amide-functionalized PBIs form one-dimensional fibrous nanostructures as the thermodynamically favored states in solvents of low polarity. Our in-depth studies revealed, however, that the kinetic behavior of their supramolecular polymerization is dependent on the spacer length. Propylene- and pentylene-tethered PBIs follow a similar polymerization process as previously observed for the ethylene-tethered PBI. Thus, the monomers of these PBIs are kinetically trapped in conformationally restricted states through intramolecular hydrogen bonding between the amide and imide groups. In contrast, the intramolecularly hydrogen-bonded monomers of butylene-tethered PBI spontaneously self-assemble into nanoparticles, which constitute an off-pathway aggregate state with regard to the thermodynamically stable fibrous supramolecular polymers obtained. Thus, for this class of π-conjugated system, an unprecedented off-pathway aggregate with high kinetic stability could be realized for the first time by introducing an alkyl linker of optimum length (C4 chain) between the amide and imide groups. Our current system with an energy landscape of two competing nucleated aggregation pathways is applicable to the kinetic control over the supramolecular polymerization by the seeding approach.
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- 2016
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29. Giants, dwarfs and the environment - metamorphic trait plasticity in the common frog.
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Grözinger F, Thein J, Feldhaar H, and Rödel MO
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- Animal Distribution, Animals, Body Size, Body Weight, Germany, Larva anatomy & histology, Ponds, Population Density, Predatory Behavior, Rana temporaria anatomy & histology, Larva growth & development, Metamorphosis, Biological, Rana temporaria growth & development
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In order to understand adaptation processes and population dynamics, it is central to know how environmental parameters influence performance of organisms within populations, including their phenotypes. The impact of single or few particular parameters in concert was often assessed in laboratory and mesocosm experiments. However, under natural conditions, with many biotic and abiotic factors potentially interacting, outcomes on phenotypic changes may be different. To study the potential environmental impact on realized phenotypic plasticity within a natural population, we assessed metamorphic traits (developmental time, size and body mass) in an amphibian species, the European common frog Rana temporaria, since a) larval amphibians are known to exhibit high levels of phenotypic plasticity of these traits in response to habitat parameters and, b) the traits' features may strongly influence individuals' future performance and fitness. In 2007 we studied these metamorphic traits in 18 ponds spread over an area of 28 km2. A subset of six ponds was reinvestigated in 2009 and 2010. This study revealed locally high variances in metamorphic traits in this presumed generalist species. We detected profound differences between metamorphing froglets (up to factor ten); both between and within ponds, on a very small geographic scale. Parameters such as predation and competition as well as many other pond characteristics, generally expected to have high impact on development, could not be related to the trait differences. We observed high divergence of patterns of mass at metamorphosis between ponds, but no detectable pattern when metamorphic traits were compared between ponds and years. Our results indicate that environment alone, i.e. as experienced by tadpoles sharing the same breeding pond, can only partly explain the variability of metamorphic traits observed. This emphasizes the importance to assess variability of reaction norms on the individual level to explain within-population variability.
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- 2014
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30. Does clinical diagnosis indicate ocular chlamydial infection in areas with a low prevalence of trachoma?
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Thein J, Zhao P, Liu H, Xu J, Jha H, Miao Y, Pizzarello L, Tapert L, Schachter J, Mabon M, Osaki-Holm S, Lietman T, and Paxton A
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- Adolescent, Adult, Aged, Child, Child, Preschool, China epidemiology, Chlamydia trachomatis genetics, Chlamydia trachomatis isolation & purification, Conjunctiva microbiology, DNA, Bacterial analysis, Female, Humans, Infant, Male, Middle Aged, Nepal epidemiology, Polymerase Chain Reaction, Prevalence, Trachoma microbiology, Trachoma diagnosis, Trachoma epidemiology
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The WHO has initiated a global program to eliminate trachoma. This program includes mass antibiotic administrations to reduce the prevalence of Chlamydia trachomatis, the causative agent in trachoma. DNA amplification tests are the most sensitive methods to diagnose C. trachomatis infection, but are expensive and not typically performed in trachoma-endemic areas. Trachoma programs use clinical examination to determine which communities and which individuals within communities would benefit from antibiotic treatment, so understanding the relationship between clinical activity and chlamydial infection is important. In this study, we determine what percent of individuals with clinically active trachoma are infected with chlamydia in low prevalence communities of China and Nepal (with <10% clinical activity in children), and compare this against a high prevalence community of Nepal (with >30% clinical activity in children). In the low prevalence areas, only 8% clinically active cases had evidence of chlamydia. In the high prevalence community, 70% of clinically active cases harbored chlamydia. These results imply that clinical activity is less indicative of infection at a lower prevalence. In the context of a trachoma program, both clinically active cases and the community as a whole may stand to benefit less from antibiotic treatment in lower prevalence areas.
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- 2002
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31. Aquatic-based rehabilitation and training for the shoulder.
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Thein JM and Brody LT
- Abstract
Objective: To describe the application of aquatic rehabilitative exercise to injuries of the upper extremity., Background: Water has been used for centuries as a medium for rehabilitation, relaxation, and training. Athletes use the pool to rehabilitate specific injuries, as a training medium during injury recovery, and as an alternative training site. The pool can be used to rehabilitate a number of upper extremity impairments, as well as to restore functional movement patterns in a resistive medium., Description: Exercises can be modified to be performed in pools of varying size and depth. Well-chosen equipment will enhance the rehabilitative opportunities for the clinician and patient., Clinical Advantages: All aspects of the rehabilitation program, including passive stretching, resistive exercise, functional movement patterns, and cardiovascular training, can take place in the same location. The water's warmth and buoyancy enhance stretching, while the buoyancy allows initiation of resistive exercise at a low level. The water's viscosity provides resistance throughout a movement pattern in any plane.
- Published
- 2000
32. Nonoperative treatment for patellofemoral pain.
- Author
-
Brody LT and Thein JM
- Subjects
- Femur, Humans, Knee, Orthotic Devices, Pain etiology, Patella, Knee Joint, Pain rehabilitation, Physical Therapy Modalities methods
- Abstract
Patellofemoral pain, often called patellofemoral stress syndrome or patellofemoral joint dysfunction, is a commonly seen knee pain syndrome in patients of all ages. It is often a frustrating problem for both the patient and the clinician, as the source of pain can be elusive, making treatment choices difficult. Strategies have been proposed based upon potential sources of pain, including both operative techniques as well as conservative management. Current nonoperative treatment strategies and techniques in the treatment of patellofemoral pain are reviewed. Recommendations and criteria for progression of rehabilitation and suggestions for future research regarding patellofemoral pain are suggested.
- Published
- 1998
- Full Text
- View/download PDF
33. Aquatic-based rehabilitation and training for the elite athlete.
- Author
-
Thein JM and Brody LT
- Subjects
- Cardiovascular Physiological Phenomena, Hemodynamics, Humans, Postural Balance, Weight-Bearing, Athletic Injuries rehabilitation, Exercise Therapy, Physical Fitness, Sports
- Abstract
Elite athletes are competing for longer seasons, training more hours, and taking less time off. This schedule may predispose the elite athlete to overuse injuries. When an injury occurs, aquatic-based rehabilitation may expedite the recovery process, as effective cardiovascular and musculoskeletal training may be accomplished by aquatic exercise. The pool may be used both during rehabilitation and postrecovery as an adjunctive tool. Knowledge of the unique physical properties of water, as well as the physiological responses to immersion both at rest and during exercise, will aid the physical therapist when designing a rehabilitation or training program for the athlete. Understanding the principles of movement in water will provide a foundation for creative use of water's unique properties.
- Published
- 1998
- Full Text
- View/download PDF
34. The female athlete.
- Author
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Thein LA and Thein JM
- Subjects
- Female, Humans, Menstruation Disturbances metabolism, Nutritional Physiological Phenomena, Body Composition physiology, Menstruation Disturbances etiology, Sports physiology
- Abstract
Since the passage of Title IX in 1972, women's participation in physical activity and sports has increased significantly. A concurrent expansion in the body of knowledge regarding women and sports has occurred. Questions regarding menstrual dysfunction and exercise continue, while new questions about menstrual dysfunction and its effect on bone mineral density have arisen. Physical and physiological differences between men and women not only guide treatment, but help fuel policy decisions regarding competition between males and females. It is essential for the physical therapist to remain current on issues related to women and sports in order to better advise and treat the female athlete.
- Published
- 1996
- Full Text
- View/download PDF
35. Ergogenic aids.
- Author
-
Thein LA, Thein JM, and Landry GL
- Subjects
- Anabolic Agents adverse effects, Animals, Caffeine pharmacology, Clenbuterol pharmacology, Erythropoietin pharmacology, Growth Hormone pharmacology, Growth Hormone physiology, Hemodynamics drug effects, Humans, Muscle, Skeletal drug effects, Substance Abuse Detection, Anabolic Agents pharmacology, Doping in Sports, Exercise physiology
- Abstract
In the context of sport, an ergogenic aid can be broadly defined as a technique or substance used for the purpose of enhancing performance. Ergogenic aids have been classified as nutritional, pharmacologic, physiologic, or psychologic and range from use of accepted techniques such as carbohydrate loading to illegal and unsafe approaches such as anabolic-androgenic steroid use. The efficacy of many of these techniques is controversial, whereas the deleterious side effects are clear. The purpose of this article is to review the epidemiology, administration, efficacy, pharmacology, and side effects of commonly used ergogenic aids. Physical therapists should be able to recognize the signs of ergogenic aid abuse in individuals under their care, and they should be aware of the side effects of these aids. Moreover, the physical therapist can serve as a resource for those individuals seeking information on the risks and benefits of ergogenic aids.
- Published
- 1995
- Full Text
- View/download PDF
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