@article{LabudekSchweizerRothetal.2019,
  author    = {Labudek, Sarah and Schweizer, Geoffrey and Roth, Anika and Pizzera, Alexandra and Plessner, Henning and Brand, Ralf},
  title     = {REFS-D},
  series = {Zeitschrift f{\"u}r Sportpsychologie},
  volume    = {26},
  journal   = {Zeitschrift f{\"u}r Sportpsychologie},
  number    = {1},
  publisher = {Hogrefe},
  address   = {G{\"o}ttingen},
  issn      = {1612-5010},
  doi       = {10.1026/1612-5010/a000256},
  pages     = {15 -- 24},
  year      = {2019},
  abstract  = {Ziel des vorliegenden Artikels ist die teststatistische {\"U}berpr{\"u}fung und Validierung einer deutschsprachigen Version der Referee Self-Efficacy Scale (REFS). Die REFS erfasst im englischsprachigen Original die Selbstwirksamkeit von Schiedsrichterinnen und Schiedsrichtern mit den Subskalen Wissen {\"u}ber das Spiel, Entscheidungsfindung, Druck und Kommunikation. Die Items wurden mit Hilfe der {\"U}bersetzung-R{\"u}ck{\"u}bersetzung ins Deutsche {\"u}bertragen. Die Struktur und die psychometrischen Eigenschaften der deutschen Items wurden anhand einer Stichprobe aus 265 deutschsprachigen Fußballschiedsrichterinnen und -schiedsrichtern {\"u}berpr{\"u}ft. Da die im englischsprachigen Original vorgeschlagene Skalenzuordnung der REFS nach der {\"U}bersetzung ins Deutsche nicht replizierbar war, wurden Items mit mangelhaften Skaleneigenschaften aus der deutschsprachigen REFS-Version (REFS-D) ausgeschlossen. Das Resultat der Analysen ist eine Skala mit acht Items, die sich drei Subskalen, Spielumsetzung, Druck und Kommunikation, zuordnen lassen. Die REFS-D weist zufriedenstellende interne Konsistenzen und signifikante mittelhohe Korrelationen mit allgemeiner Selbstwirksamkeit auf. Trotz einiger Einschr{\"a}nkungen stellt die REFS-D als {\"o}konomische Skala einen Ansatzpunkt f{\"u}r zuk{\"u}nftige Forschung dar.},
  language  = {de}
}
@article{TepelArmbrusterGroenetal.2013,
  author    = {Tepel, Martin and Armbruster, Franz Paul and Groen, Hans Juergen and Scholze, Alexandra and Reichetzeder, Christoph and Roth, Heinz J{\"u}rgen and Hocher, Berthold},
  title     = {Nonoxidized, biologically active parathyroid hormone determines mortality in hemodialysis patients},
  series = {The journal of clinical endocrinology \& metabolism},
  volume    = {98},
  journal   = {The journal of clinical endocrinology \& metabolism},
  number    = {12},
  publisher = {Endocrine Society},
  address   = {Chevy Chase},
  issn      = {0021-972X},
  doi       = {10.1210/jc.2013-2139},
  pages     = {4744 -- 4751},
  year      = {2013},
  abstract  = {Background: It was shown that nonoxidized PTH (n-oxPTH) is bioactive, whereas the oxidation of PTH results in a loss of biological activity. Methods: In this study we analyzed the association of n-oxPTH on mortality in hemodialysis patients using a recently developed assay system. Results: Hemodialysis patients (224 men, 116 women) had a median age of 66 years. One hundred seventy patients (50\%) died during the follow-up period of 5 years. Median n-oxPTH levels were higher in survivors (7.2 ng/L) compared with deceased patients (5.0 ng/L; P = .002). Survival analysis showed an increased survival in the highest n-oxPTH tertile compared with the lowest n-oxPTH tertile (chi(2), 14.3; P = 0008). Median survival was 1702 days in the highest n-oxPTH tertile, whereas it was only 453 days in the lowest n-oxPTH tertile. Multivariable-adjusted Cox regression showed that higher age increased odds for death, whereas higher n-oxPTH reduced the odds for death. Another model analyzing a subgroup of patients with intact PTH (iPTH) concentrations at baseline above the upper normal range of the iPTH assay (70 ng/L) revealed that mortality in this subgroup was associated with oxidized PTH but not with n-oxPTH levels. Conclusions: The predictive power of n-oxPTH and iPTH on the mortality of hemodialysis patients differs substantially. Measurements of n-oxPTH may reflect the hormone status more precisely. The iPTH-associated mortality is most likely describing oxidative stress-related mortality.},
  language  = {en}
}
@inproceedings{HocherArmbrusterScholzeetal.2013,
  author    = {Hocher, Berthold and Armbruster, Franz Paul and Scholze, Alexandra and Marckmann, Peter and Reichetzeder, Christoph and Roth, Heinz J{\"u}rgen and Tepel, Martin},
  title     = {Non-oxidized, biological active parathyroid hormone determines motality in hemodialsysis patients},
  series = {Nephrology, dialysis, transplantation},
  volume    = {28},
  booktitle = {Nephrology, dialysis, transplantation},
  publisher = {Oxford Univ. Press},
  address   = {Oxford},
  issn      = {0931-0509},
  pages     = {33 -- 33},
  year      = {2013},
  language  = {en}
}
@article{HoffBiskabornDirksenetal.2015,
  author    = {Hoff, Ulrike and Biskaborn, Boris and Dirksen, Veronika G. and Dirksen, Oleg and Kuhn, Gerhard and Meyer, Hanno and Nazarova, Larisa B. and Roth, Alexandra and Diekmann, Bernhard},
  title     = {Holocene environment of Central Kamchatka, Russia: Implications from a multi-proxy record of Two-Yurts Lake},
  series = {Global and planetary change},
  volume    = {134},
  journal   = {Global and planetary change},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0921-8181},
  doi       = {10.1016/j.gloplacha.2015.07.011},
  pages     = {101 -- 117},
  year      = {2015},
  abstract  = {Within the scope of Russian German palaeoenvironmental research, Two-Yurts Lake (TYL, Dvuh-Yurtochnoe in Russian) was chosen as the main scientific target area to decipher Holocene climate variability on Kamchatka. The 5 x 2 km large and 26 m deep lake is of proglacial origin and situated on the eastern flank of Sredinny Ridge at the northwestern end of the Central Kamchatka Valley, outside the direct influence of active volcanism. Here, we present results of a multi-proxy study on sediment cores, spanning about the last 7000 years. The general tenor of the TYL record is an increase in continentality and winter snow cover in conjunction with a decrease in temperature, humidity, and biological productivity after 5000-4500 cal yrs BP, inferred from pollen and diatom data and the isotopic composition of organic carbon. The TYL proxy data also show that the late Holocene was punctuated by two colder spells, roughly between 4500 and 3500 cal yrs BP and between 1000 and 200 cal yrs BP, as local expressions of the Neoglacial and Little Ice Age, respectively. These environmental changes can be regarded as direct and indirect responses to climate change, as also demonstrated by other records in the regional terrestrial and marine realm. Long-term climate deterioration was driven by decreasing insolation, while the short-term climate excursions are best explained by local climatic processes. The latter affect the configuration of atmospheric pressure systems that control the sources as well as the temperature and moisture of air masses reaching Kamchatka. (C) 2015 Elsevier B.V. All rights reserved.},
  language  = {en}
}
@article{ScholzeLiuPedersenetal.2014,
  author    = {Scholze, Alexandra and Liu, Ying and Pedersen, Lise and Xia, Shengqiang and Roth, Heinz J. and Hocher, Berthold and Rasmussen, Lars Melholt and Tepel, Martin},
  title     = {Soluble alpha-Klotho and its relation to kidney function and fibroblast growth factor-23},
  series = {The journal of clinical endocrinology \& metabolism},
  volume    = {99},
  journal   = {The journal of clinical endocrinology \& metabolism},
  number    = {5},
  publisher = {Endocrine Society},
  address   = {Washington},
  issn      = {0021-972X},
  doi       = {10.1210/jc.2013-4171},
  pages     = {E855 -- E861},
  year      = {2014},
  abstract  = {Context: Relations between fibroblast growth factor-23 (FGF-23), soluble alpha-klotho (s-alpha-klotho), and kidney function in chronic kidney disease (CKD) are still unclear. Especially the role of s-alpha-klotho requires further study. Objectives: Our objectives were to analyze the relation of s-alpha-klotho to estimated glomerular filtration rate (eGFR), FGF-23, and other parameters of calcium-phosphate metabolism and to investigate the response of s-alpha-klotho to cholecalciferol. Patients, Design, and Setting: Twenty-four CKD (stage 1-5) patients participated in this 8-week randomized controlled trial (vitamin D and chronic renal insufficiency). Interventions: Interventions included 40 000 IU cholecalciferol or placebo weekly. Main Outcome Measure: S-alpha-klotho was determined by ELISA with antihuman klotho antibodies 67G3 and 91F1. Results: For all patients, s-alpha-klotho concentrations did not differ between CKD stages. When patients were subdivided based on FGF-23 concentrations, a positive association of s-alpha-klotho with eGFR became apparent in patients with lower than median FGF-23 concentrations but not in those above median value. Patients with s-alpha-klotho below 204 pg/mL showed higher age, lower phosphate clearance, and lower bone-specific alkaline phosphatase compared with patients with higher s-alpha-klotho. Treatment with cholecalciferol significantly increased 1,25-dihydroxyvitamin D. The increase of FGF-23 had only borderline significance. There was no significant effect of high-dose cholecalciferol administration for 8 weeks on plasma s-alpha-klotho. Conclusions: CKD patients with s-alpha-klotho below 204 pg/mL had higher age, lower phosphate clearance, and lower bone-specific alkaline phosphatase. An association of s-alpha-klotho with eGFR was observed only in the presence of close to normal, but not high, FGF-23 concentrations. Cholecalciferol treatment did not change s-alpha-klotho concentrations.},
  language  = {en}
}