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Dem Leiden Ausdruck verleihen: Biblische und liturgiewissenschaftliche Perspektiven auf Klagetexte
No full textInvestigating the neural mechanisms of transcranial direct current stimulation effects on human cognition: current issues and potential solutions
No full textTranscranial direct current stimulation (tDCS) has been studied extensively for its potential to enhance human cognitive functions in healthy individuals and to treat cognitive impairment in various clinical populations. However, little is known about how tDCS modulates the neural networks supporting cognition and the complex interplay with mediating factors that may explain the frequently observed variability of stimulation effects within and between studies. Moreover, research in this field has been characterized by substantial methodological variability, frequent lack of rigorous experimental control and small sample sizes, thereby limiting the generalizability of findings and translational potential of tDCS. The present manuscript aims to delineate how these important issues can be addressed within a neuroimaging context, to reveal the neural underpinnings, predictors and mediators of tDCS-induced behavioral modulation. We will focus on functional magnetic resonance imaging (fMRI), because it allows the investigation of tDCS effects with excellent spatial precision and sufficient temporal resolution across the entire brain. Moreover, high resolution structural imaging data can be acquired for precise localization of stimulation effects, verification of electrode positions on the scalp and realistic current modeling based on individual head and brain anatomy. However, the general principles outlined in this review will also be applicable to other imaging modalities. Following an introduction to the overall state-of-the-art in this field, we will discuss in more detail the underlying causes of variability in previous tDCS studies. Moreover, we will elaborate on design considerations for tDCS-fMRI studies, optimization of tDCS and imaging protocols and how to assure high-level experimental control. Two additional sections address the pressing need for more systematic investigation of tDCS effects across the healthy human lifespan and implications for tDCS studies in age-associated disease, and potential benefits of establishing large-scale, multidisciplinary consortia for more coordinated tDCS research in the future. We hope that this review will contribute to more coordinated, methodologically sound, transparent and reproducible research in this field. Ultimately, our aim is to facilitate a better understanding of the underlying mechanisms by which tDCS modulates human cognitive functions and more effective and individually tailored translational and clinical applications of this technique in the future
Temporal stability of optimism and pessimism (LOT-R) over 6 years in the general population
No full textObjective:
The aims of this study were to examine changes in habitual optimism over a six-year period and to analyze the relationship between changes in optimism and changes in other quality of life-related variables.
Method:
A randomly selected community sample of the German adult general population (N = 4,965) was surveyed twice, with a time interval of 6.04 years.
Results:
During the course of the 6 years, the mean score of the LOT-R total scale improved (effect size d = 0.11). The temporal stability in terms of the test–retest correlation was r = 0.61 for the total sample. There were only marginal gender differences in this temporal stability, however, the stability in the oldest age group ≥70 years (r = 0.50) was lower than the stability of the other age groups. The cross-sectional correlations showed clear relationships between optimism on the one hand and quality of life, life satisfaction, social support, and low levels of anxiety and physical complaints on the other. The corresponding longitudinal correlations between changes in optimism and changes in the other variables were less pronounced, but in the same direction.
Conclusion:
The study confirmed the applicability of the LOT-R in longitudinal studies. In samples with participants of 70 years and above, the limited stability in the optimism assessments needs to be considered in clinical practice and epidemiologic research
Enhancement of a musculoskeletal shoulder model in OpenSim and validation with in vivo force data: The influence of OpenSim workflow configurations
No full textMusculoskeletal modeling is widely used to investigate biomechanical mechanisms that are difficult or impossible
to measure experimentally, such as glenohumeral joint reaction force (GH-JRF), used to characterize shoulder
stability. However, objective quality criteria for OpenSim workflow configurations remain limited. This study evaluated
the influence of different modeling choices on GH-JRF estimation accuracy using in vivo reference data from an
instrumented shoulder prosthesis (Orthoload). In addition, commonly used quality metrics, scaling RMSE and
inverse kinematic (IK) RMSE, were assessed as indicators of dynamic simulation accuracy. Experimental kinematic
data were reprocessed through multiple workflow configurations, combining two musculoskeletal models, five scaling
methods, two IK setups, and three force calculation approaches across unloaded abduction, forward flexion and
backward flexion. GH-JRF accuracy was defined using RMSE and waveform similarity. Model selection and force
calculation approach showed the strongest influence on GH-JRF accuracy, whereas scaling methods and IK setup
selection had little systematic effect. No consistent association was found between scaling or IK accuracy and GHJRF
estimation. These findings indicate, that improvements in scaling or kinematic accuracy do not necessarily
translate into enhanced dynamic validity and highlight the need for outcome specific validation in musculoskeletal
shoulder modeling
Selbstevaluation in der Orthopädie und Unfallchirurgie: Inverse Schulterendoprothetik - Das klinische Outcome in Abhängigkeit der zugrundeliegenden Indikation
No full textDie inverse Schulterendoprothetik ist im vergangenen Jahrzehnt zunehmend in den
Fokus und aus dem Schatten der Knie- und Hüftendoprothetik gerückt. Ursprünglich
galt nur die Rotatorenmanschettendefektarthropathie als eindeutige Indikation für die
Implantation einer RSA, heute sollte sowohl bei degenerativen als auch bei
traumatischen Erkrankungen die Entscheidung für eine RSA erwogen werden.
Ziel dieser Arbeit war es, 1) das klinische Outcome in Abhängigkeit der
zugrundeliegenden Indikation nach Implantation einer RSA zu untersuchen sowie 2)
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zu zeigen, dass die Selbstevaluation auch in der Orthopädie und Unfallchirurgie zu
vergleichbaren und zuverlässigen Ergebnissen führt.
In einer monozentrischen und retrospektiven Studie konnten 136 Patienten, welche
zwischen 2012 und 2022 mit einer RSA versorgt wurden, mittels 3 verschiedenen
postalisch versandter Fragebögen im Verfahren der Selbstevaluation nachuntersucht
werden. Erfasst wurden mithilfe des Constant Scores, des DASH Scores und des EQ-
5D-5L Bewegungsumfang, Funktionalität und Lebensqualität.
Die Patienten wurden anhand ihrer zugrundeliegenden Indikation in drei Gruppen
gegliedert: primäre Frakturen, sekundäre Interventionen, degenerative Erkrankungen.
Die Gruppe der Sekundärversorgungen setzte sich sehr heterogen zusammen, daher
trafen wir eine weitere Unterteilung: posttraumatische Omarthrosen (Gruppe 1),
posttraumatische Humeruskopfnekrosen (Gruppe 2), fehlverheilte proximale
Humerusfrakturen (Gruppe 3), Sekundärlösung nach Osteosynthese (Gruppe 4),
Lockerungen von Prothesen (Gruppe 5), Luxationen von Prothesen (Gruppe 6),
Infektionen (Gruppe 7).
Außerdem konnten wir 35 Patienten in der Ambulanz des Universitätsklinikums Leipzig
nachuntersuchen.
Das durchschnittliche Follow-up betrug 48 Monate (min. 6; max. 139). Die Gruppe der
degenerativen Erkrankungen zeigte die höchsten Score-Ergebnisse: 58 Punkte (min.
13; max. 87) im CS, einen Mittelwert von 35 (min. 82; max. 1) im DS und ein Ergebnis
von 0,72 (min. 0,028; max. 1) im EQ.
Die niedrigsten Ergebnisse erzielte die Gruppe der Sekundärversorgungen: 49 Punkte
(Min. 18; Max. 91) im CS, 42 (Min. 87; Max. 6) im DS, 0,68 (Min. -0,57; Max. 1) im EQ.
Knapp oberhalb lagen die Ergebnisse der primären Frakturversorgungen: CS von 52
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Punkten (Min. 20; Max. 93), 40 Punkte (Min. 73; Max. 4) im DS und 0,75 (Min. 0,19;
Max. 1 im EQ).
Die höchsten Ergebnisse zeigte Gruppe 7 mit 68 (Min. 24, Max. 90) Punkten im CS,
23 (Min. 38, Max. 6) Punkten im DS und 0,91(Min. 0,796, Max. 1) im EQ, dicht gefolgt
von Gruppe 5. Die Gruppen 1-4 rangierten im CS zwischen 38 und 49 Punkten. Gruppe
6 präsentierte die niedrigsten Ergebnisse: 37 im CS (Min. 18; Max. 61), 54 (Min. 82;
Max. 82) im DS und im EQ 0,415 (Min. -0,57; Max. 1).
Beim Vergleich der Inklinationswinkel konnten wir keinen klinisch relevanten
Unterschied feststellen. Die klinische Untersuchung zeigte Übereinstimmung mit den
Selbstevaluationen der Patienten.
Trotz der verhältnismäßig kleinen Patientenkohorte ist es uns gelungen, klinisch
relevante Unterschiede zwischen den einzelnen Indikationsgruppen aufzuzeigen.
Insbesondere bei den verschiedenen Ätiologien, welche zu einer Sekundärversorgung
mittels RSA führten, zeigten sich klare Abstufungen. Die ausbleibenden relevanten
Unterschiede zwischen den Inklinationswinkeln stärken unsere These der
Abhängigkeit des klinischen Outcomes von der zugrundeliegenden Indikation
ungemein.
Die Selbstevaluation inklusive selbstberichteter Bewegungsumfänge ist in der
Orthopädie und Unfallchirurgie noch kein allgemeingültiger Goldstandard. Wir konnten
mit unseren Ergebnissen belegen, dass dieses Selbstbefragungs-Instrument
insbesondere im Hinblick auf die zurückliegende Covid-19-Pandemie ein
zuverlässiges Tool ist, welches reliable Ergebnisse liefert.:Abkürzungsverzeichnis
1 Einleitung
1.1 Das Glenohumeralgelenk
1.2 Die inverse Schulterendoprothese
1.2.1 Epidemiologie
1.2.2 Indikationen
1.2.3 Biomechanik der inversen Schulterendoprothese
1.3 Selbstevaluation in der Orthopädie und Unfallchirurgie
2 Zielsetzung
3 Patienten & Methoden
3.1 Studiendesign
3.2 Erhobene Daten
3.3 Indikationen
3.4 Operative Versorgung
3.5 Fragebögen
3.5.1 Constant Score
3.5.2 DASH Score
3.5.3 EQ-5D-5L
3.6 Selbstevaluation und klinische Untersuchung
3.7 Statistik
4 Ergebnisse
4.1 Beschreibung des gesamten Patientenkollektives
4.1.1 Epidemiologische Daten
4.1.2 Indikationen
4.2 Auswertung der einzelnen Gruppen
4.2.1 Primäre Frakturen
4.2.2 Sekundärversorgungen
4.2.3 Degenerative Erkrankungen
4.3 Untergruppen der Sekundärversorgung
4.4 Einzelauswertung Constant-Score
4.5 Vergleich der Selbstevaluation mit der klinischen Untersuchung
4.6 Vergleich der Inklinationswinkel
5 Diskussion
5.1 Patientenkollektiv
5.2 Constant-Score in Abhängigkeit der Indikationen
5.3 Erfassung von Alltagskompetenz und Lebensqualität
5.4 Sekundärversorgungen
5.4.1 Frakturfolgeversorgungen (Gruppen 1-4)
5.4.2 Lockerung und Luxation einer Prothese (Gruppen 5, 6)
5.4.3 Infektionen (Gruppe 7)
5.5 Selbstevaluation und klinische Untersuchung
5.6 Inklinationswinkel
5.7 Fazit und Ausblick
6 Limitationen
7 Zusammenfassung der Arbeit
8 Literaturverzeichnis
9 Anlagen
9.1 Abbildungsverzeichnis
9.2 Tabellenverzeichnis
9.3 Constant-Score
9.4 DASH-Score
9.5 EQ-5D-5L
10 Erklärung über die eigenständige Abfassung der Arbeit
11 Curriculum vitae
12 Danksagun
Non-native Accents among School Beginners and Teacher Expectations for Future Student Achievements
No full textBased on sociological, economic, and social-psychological theories of discrimination and bias, this study addresses non-native accents among ethnic minority students as they begin school and explores effects of such accents on their teachers’ achievement expectations. Using a unique data set of first graders in Germany, the analysis reveals that a non-native accent is relevant to teachers’ expectations net of student skills, abilities, and other background variables. Associations are stronger in the language domain than in mathematics, indicating that teachers perceive accent-free speech as a language-learning requirement. However, residual influences of non-native accents on teacher expectations also exist in the math domain and persist even after prolonged periods of teacher-student interaction. Mechanisms of statistical discrimination and stereotype-based discrimination can partially explain these effects. However, the overall pattern of results suggests a stigmatization of non-native accents, potentially resulting from the activation of negative associations related to foreignness and disfluency
Non-ischemic cerebral enhancing (NICE) lesions after flow diversion for intracranial aneurysms: a multicenter study
No full textBackground Non- ischemic cerebral enhancing (NICE)
lesions have been reported as a rare complication of
various neuroendovascular procedures, but information
on their incidence after flow diversion is scant. It is
unclear if specific devices or novel coating technologies
may impact their occurrence.
Methods We conducted a multicenter study on
the incidence of NICE lesions after flow diverter (FD)
implantation for cerebral aneurysm treatment.
Results Eight centers identified 15 patients and
provided detailed data. The clinical presentation
ranged from asymptomatic to hemiplegia and cognitive
impairment. The mean time to diagnosis after treatment
was 65.1±101.5 days. Five centers disclosed information
on all of their 1201 FD procedures during the inclusion
period (2015–2022), during which 12 patients were
diagnosed with NICE lesions in these institutions—that
is, an incidence of 1%. FD coatings did not increase the
incidence (6/591 patients (1%) treated with surface-
modified FD vs 6/610 patients (1%) treated with bare
FD; P=1.00). Significantly increased rates of 3.7% (6
cases in 161 procedures; P<0.01) and 3.3% (5 cases in
153 procedures; P<0.01) were found with stents of two
specific product lines. The use of one product line was
associated with a significantly lower incidence (0 cases in
499 procedures (0%); P<0.01).
Conclusions Novel stent coatings are not associated
with an increased incidence of NICE lesions. The
incidence rate of 1% suggests that these lesions may
occur more often after flow diversion than after other
endovascular treatments. We found a concerning
accumulation of NICE lesion cases when FDs from two
product families were used
A Science Friction Story: Molecular Interactions in Semiflexible Polymer Networks
No full textEstablished model theories, developed to capture the mechanical behavior of soft, complex materials composed of semiflexible polymers, assume that entropic interactions between filaments are primarily responsible for determining the mechanical response. In recent studies, the generally accepted tube model has been challenged in terms of this basic assumption about filament–filament interactions, but also because of its predictions regarding the frequency dependence of the elastic modulus in the intermediate frequency regime. A central question is how molecular interactions and friction between network constituents influence the rheological response of isotropic entangled networks of semiflexible polymers. It has been previously shown that friction forces between aligned pairs of actin filaments are not negligible. Here, the influence of friction forces and attractive interactions on network rheology is systematically investigated by means of targeted surface modification. It is shown that these forces have a qualitative and quantitative influence on the viscoelastic properties of semiflexible polymer networks and contribute to their response to nonlinear deformations. By comparing two polymer model systems with respect to their surface compositions, a possible explanation is given about the origin of acting forces on a molecular level
Die Prädiktion des Therapieansprechens bei Patienten mit chronischer Hepatitis-B-Infektion durch die Quantifizierung des anti-HBc-Antikörpers
No full textApproaching Thrombospondin-1 as a Potential Target for Mesenchymal Stromal Cells to Support Liver Regeneration after Partial Hepatectomy in Mouse and Humans
No full textExtended liver resection carries the risk of post-surgery liver failure involving thrombospondin-1-mediated aggravation of hepatic epithelial plasticity and function. Mesenchymal stromal cells (MSCs), by interfering with thrombospondin-1 (THBS1), counteract hepatic dysfunction, though the mechanisms involved remain unknown. Herein, two-thirds partial hepatectomy in mice increased hepatic THBS1, downstream transforming growth factor-β3, and perturbation of liver tissue homeostasis. All these events were ameliorated by hepatic transfusion of human bone marrow-derived MSCs. Treatment attenuated platelet and macrophage recruitment to the liver, both major sources of THBS1. By mitigating THBS1, MSCs muted surgery-induced tissue deterioration and dysfunction, and thus supported post-hepatectomy regeneration. After liver surgery, patients displayed increased tissue THBS1, which is associated with functional impairment and may indicate a higher risk of post-surgery complications. Since liver dysfunction involving THBS1 improves with MSC treatment in various animal models, it seems feasible to also modulate THBS1 in humans to impede post-surgery acute liver failure