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Clinical Trajectory and Risk Stratification for Heart Failure with Preserved Ejection Fraction in a Real-World Cohort of Patients with Suspected Coronary Artery Disease
No full textBackground: Heart failure with preserved ejection fraction (HFpEF) is a widespread condition with significant morbidity and mortality. Its clinical heterogeneity may delay the diagnosis. Aim: To identify predictors of HFpEF-related hospitalizations in ambulatory patients presenting with elevated cardiovascular risk, suspected coronary artery diseases (CADs), and positive HFpEF screenings. Methods: Consecutive patients presenting with suspected CAD, enrolled in the observational LIFE-Heart study (2006–2014, NCT00497887), and meeting HFpEF criteria per the 2016 European Society of Cardiology (ESC) guidelines were categorized according to the presence of “overlapping conditions” potentially masking or contributing to their symptoms. Additional stratification using the H2FPEF score (<2: low risk, 2–5: intermediate risk, and ≥6 high risk) was performed. Follow-up for hospitalizations, reasons of hospitalization, and death spanned a median of 6 years. Results: Of 1054 patients (66 ± 10 years, 60% male, NT-pro-BNP 286, IQR 183–574 pg/mL), 53% had overlapping conditions, while 47% had “isolated HFpEF”. The H2FPEF scores classified 23%, 57%, and 20% as low-, intermediate-, and high-risk, respectively, with consistent proportions across patients with and without overlapping conditions (p = 0.91). During the follow-up observational phase, 54% were rehospitalized, 22% experienced heart failure (HF) rehospitalizations, and 11% of patients died. Multivariable logistic regression revealed a high-risk H2FPEF category as an independent predictor of HF rehospitalization in the overall cohort (odds ratio: 3.4, CI: 2.4–4.9, p < 0.01) as well as in patients with and without overlapping conditions. Furthermore, a H2FPEF score ≥ 6 was independently associated with higher mortality rates (hazard ratio: 1.8, CI: 1.2–2.6, p < 0.01) in the Cox regression analysis. Conclusions: Ambulatory patients presenting for suspected CAD and meeting HFpEF screening criteria face elevated risks for rehospitalizations over six years. Regardless of concomitant diagnoses, quantifying cardiac damage with the H2FPEF score helps in risk-stratifying patients for HF hospitalization and mortality
The interaction between acute emotional states and executive functions in youth elite soccer players
No full textIntroduction: Executive functions (EFs) are relevant for game performance in soccer and have been investigated in previous research. However, emotions are a well-known performance factor in sport competitions, which may affect performance by means of EFs. The diagnostic of EFs has mainly been performed disregarding the potential impact of emotional states. Thus, we aimed to initially analyze interaction between emotional states and EFs in two studies with male youth elite soccer players.
Methods: In the first study, 105 players (Mage = 14.97) completed computerized tasks assessing inhibition, cognitive flexibility and working memory. In the second study, 92 players (Mage = 15.17) performed adapted and validated tests of inhibition (n = 45) or cognitive flexibility (n = 47) in a soccer-specific setting (SoccerBot360). Emotional and affective states were assessed using the German Sport Emotion Questionnaire and self-assessment manikins.
Results: For the computerized tasks, results showed a significant negative correlation between switch costs accuracy and tension, r = 0.28, indicating lower error rates with higher levels of tension. In contrast, in the SoccerBot360 we found significant positive correlations for response time and tension (no-switch: r = 0.38; switch: r = 0.39) representing prolonged response times related to tension. Further, for soccer-specific inhibition, positive emotions were significantly positively correlated with response time (congruent: r = 0.32; incongruent: r = 0.32). Subsequent regression analyses also demonstrate that valence and arousal effectively explain variance in cognitive performance parameters under neutral conditions.
Discussion: Accordingly, the ambiguity of the results suggests high variability in EF performance, affective and emotional states as well as a potentially moderating influence of other variables such as context and task difficulty. Thus, future cognitive diagnostic research should integrate assessments of emotional and affective states as these may contribute to situational fluctuations in EF performance
Lament of the Walking Dead: The Lamenting Engagement with the Local Sphere, the Social Implications, and the Bodily Expression of Death in Ps 88 and Job 7
No full textFollowing the self-identification of the lamenting people as dead, this
article challenges the conventional distinction between death in life and biological
death in Ps 88 and Job 7. Genre criticism and an analysis of the rhetoric of death
reveal how both texts employ the paradoxes of a dead person’s lament as argu-
ments to God. In Ps 88, the person praying assigns themselves locally, socially, and
progressively also theologically to the deceased and consequently ends the prayer.
In contrast, Job employs his bodily decay as a walking corpse to demand peace from
God in the realm of Sheol.Der Selbst-Identifikation der Betenden als Tote folgend, stellt
der Artikel die herkömmliche Trennung zwischen dem Tod im Leben und dem bio-
logischen Tod in Ps 88 und Hiob 7 in Frage. Die Analyse der Todesrhetorik und die
Gattungskritik zeigen, wie die beiden Klagenden die Paradoxien der Klage eines
Toten als Argumente gegenüber Gott einsetzen. Während sich die betende Person
des 88. Psalms lokal, sozial und zunehmend auch theologisch den Verstorbenen
zuordnet und daraufhin das Gebet beendet, klagt Hiob als wandelnde Leiche vehe-
ment Ruhe vor Gott in der Scheol ein
Novel machine learning approach toward classification model of HIV-1 integrase inhibitors
No full textHIV-1 (human immunodeficiency virus-1) has been causing severe pandemics by attacking the immune system of its host. Left untreated, it can lead to AIDS (acquired immunodeficiency syndrome), where death is inevitable due to opportunistic diseases. Therefore, discovering new antiviral drugs against HIV-1 is crucial. This study aimed to explore a novel machine learning approach to classify compounds that inhibit HIV-1 integrase and screen the dataset of repurposing compounds. The present study had two main stages: selecting the best type of fingerprint or molecular descriptor using the Wilcoxon signed-rank test and building a computational model based on machine learning. In the first stage, we calculated 16 different types of fingerprint or molecular descriptors from the dataset and used each of them as input features for 10 machine-learning models, which were evaluated through cross-validation. Then, a meta-analysis was performed with the Wilcoxon signed-rank test to select the optimal fingerprint or molecular descriptor types. In the second stage, we constructed a model based on the optimal fingerprint or molecular descriptor type. This data followed the machine learning procedure, including data preprocessing, outlier handling, normalization, feature selection, model selection, external validation, and model optimization. In the end, an XGBoost model and RDK7 fingerprint were identified as the most suitable. The model achieved promising results, with an average precision of 0.928 ± 0.027 and an F1-score of 0.848 ± 0.041 in cross-validation. The model achieved an average precision of 0.921 and an F1-score of 0.889 in external validation. Molecular docking was performed and validated by redocking for docking power and retrospective control for screening power, with the AUC metrics being 0.876 and the threshold being identified at −9.71 kcal mol−1. Finally, 44 compounds from DrugBank repurposing data were selected from the QSAR model, then three candidates were identified as potential compounds from molecular docking, and PSI-697 was detected as the most promising molecule, with in vitro experiment being not performed (docking score: −17.14 kcal mol−1, HIV integrase inhibitory probability: 69.81%
Understanding optimal cadence dynamics: a systematic analysis of the power-velocity relationship in track cyclists with increasing exercise intensity
No full textBackground: This study aimed to investigate the changes in force-velocity (F/v) and power-velocity (P/v) relationships with increasing work rate up to maximal oxygen uptake and to assess the resulting alterations in optimal cadence, particularly at characteristic metabolic states.
Methods: Fourteen professional track cyclists (9 sprinters, 5 endurance athletes) performed submaximal incremental tests, high-intensity cycling trials, and maximal sprints at varied cadences (60, 90, 120 rpm) on an SRM bicycle ergometer. Linear and non-linear regression analyses were used to assess the relationship between heart rate, oxygen uptake (V.O2), blood lactate concentration and power output at each pedaling rate. Work rates linked to various cardiopulmonary and metabolic states, including lactate threshold (LT1), maximal fat combustion (FATmax), maximal lactate steady-state (MLSS) and maximal oxygen uptake (V.O2max), were determined using cadence-specific inverse functions. These data were used to calculate state-specific force-velocity (F/v) and power-velocity (P/v) profiles, from which state-specific optimal cadences were derived. Additionally, fatigue-free profiles were generated from sprint data to illustrate the entire F/v and P/v continuum.
Results: HR, V.O2 demonstrated linear relationships, while BLC exhibited an exponential relationship with work rate, influenced by cadence (p < 0.05, η2 ≥ 0.655). Optimal cadence increased sigmoidally across all parameters, ranging from 66.18 ± 3.00 rpm at LT1, 76.01 ± 3.36 rpm at FATmax, 82.24 ± 2.59 rpm at MLSS, culminating at 84.49 ± 2.66 rpm at V.O2max (p < 0.01, η2 = 0.936). A fatigue-free optimal cadence of 135 ± 11 rpm was identified. Sprinters and endurance athletes showed no differences in optimal cadences, except for the fatigue-free optimum (p < 0.001, d = 2.215).
Conclusion: Optimal cadence increases sigmoidally with exercise intensity up to maximal aerobic power, irrespective of the athlete’s physical condition or discipline. Threshold-specific changes in optimal cadence suggest a shift in muscle fiber type recruitment toward faster types beyond these thresholds. Moreover, the results indicate the need to integrate movement velocity into Henneman’s hierarchical size principle and the critical power curve. Consequently, intensity zones should be presented as a function of movement velocity rather than in absolute terms
Migrating the Basic Programming Paradigms course materials from a private to a public repository on GitHub
No full textKriterien der Rechtsformwahl
No full textDie vorliegende Arbeit befasst sich mit der Rechtsformwahl von Unternehmen und untersucht die hierbei relevanten Entscheidungskriterien aus rechtstatsächlicher Perspektive. Ausgangspunkt ist eine systematische Aufarbeitung des bestehenden Forschungsstandes, auf deren Grundlage Forschungsfragen und Hypothesen zur Rechtsformwahl entwickelt werden. Empirisch basiert die Arbeit auf einer Befragung von Unternehmensgründern (Oktober 2018), deren Ergebnisse zunächst deskriptiv ausgewertet und anschließend mithilfe inferenzstatistischer Verfahren überprüft werden; ergänzend wird eine explorative Faktorenanalyse eingesetzt, um übergreifende Strukturmuster der Entscheidungskriterien herauszuarbeiten. Inhaltlich stehen die Motive der Rechtsformwahl, der Einfluss externer Beratung sowie mögliche spätere Änderungsabsichten im Mittelpunkt der Analyse. Die Arbeit ordnet die gewonnenen Befunde in den rechtlichen und ökonomischen Kontext ein und trägt zur empirischen Beschreibung der Rechtsformwahl in Deutschland bei.:A. Einleitung 1
I. Problemstellung 1
II. Gang der Untersuchung 3
B. Forschungsstand 5
I. Begriffsbestimmung 5
II. Abgrenzung 9
III. Theoretische Ansätze 11
1. Literatur 11
a. Explizit zur Rechtsformwahl 11
b. Rechtsformwahl als Teil des Beitrags 12
c. Teilaspekte der Rechtsformwahl 13
2. Online-Angebote 15
a. Explizit zur Rechtsformwahl 15
b. Rechtsformwahl als Teil des Informationsangebots 16
IV. Empirische Ansätze 17
1. Hofmann (1988) 18
2. Zieren (1989) 19
3. Buschmann et al. (2003) 21
4. Weitere Studien 23
a. Brüderl et al. (1996) 23
b. Gries et al. (1997) 25
c. Hinz (1998) 27
d. Breithecker/Baumann (1998) 28
e. Holt (2001) 29
f. Helm et al. (2004) 30
g. Hermes (2006) 32
h. Heiss (2006) 33
i. Braun/Richter (2010) 34
j. Sell et al. (2010) 35
k. Siegel (2014) 37
5. Zusammenfassung 38
V. Ableitung von Forschungsfragen und Forschungshypothesen 39
1. Einführung zur Hypothesenableitung 39
2. Haftungsbeschränkung 43
3. Unternehmensnachfolge 48
4. Beratung 51
5. Rechtsformwechsel 55
6. Rechtsformwahlkriterien 58
a. Kriterienanzahl 58
b. Faktorenanalyse 60
C. Empirische Erhebung zur Rechtsformwahl 63
I. Zielsetzung 63
II. Konzeption der Erhebung 64
1. Untersuchungsdesign 64
2. Operationalisierung 66
a. Rechtsformwahlkriterien 66
b. Rechtsform 72
c. Beratung 73
d. Rechtsformwechsel 73
e. Optimierungspotentiale 73
f. Fragebogengestaltung 74
3. Stichprobenziehung 75
a. Definition der Grundgesamtheit 75
b. Definition der Stichprobe 75
c. „Repräsentativität“ 77
III. Durchführung der Erhebung 78
1. Datenerhebung 78
a. Online-Befragung 78
b. Anschreiben 79
c. Pilotstudie 80
d. Hauptstudie 80
2. Datenaufbereitung 81
3. Rücklaufstatistik 82
IV. Wesentliche Ergebnisse der Erhebung (Deskriptivstatistische Analyse) 84
1. Rechtsform 84
a. Abgleich mit amtlichen Daten 86
b. Abgleich mit empirischen Erhebungen 89
c. Zwischenergebnis 91
2. Beratung 91
a. Inanspruchnahme von Beratung 91
b. Beratungsquellen 93
3. Rechtsformwahlkriterien 97
a. Höchste Relevanz 99
b. Niedrigste Relevanz 102
4. Rechtsformwechsel 105
a. Wechselbereitschaft 105
(1) Indirekter Abgleich mit amtlichen Daten 105
(2) Abgleich mit empirischen Erhebungen 108
b. Gründe für den Rechtsformwechsel 109
5. Optimierungspotential 111
a. Bürokratie 113
b. Schnelleres Verfahren 117
c. Online-Gründung 121
d. Zentrale Anlaufstelle 123
e. Finanz- und Rechtsberatung 124
f. Steuerstundung 126
g. Zwischenergebnis 128
D. Inferenzstatistische Analyse 129
I. Einführung zur Hypothesenüberprüfung 130
II. Haftungsbegrenzung 133
1. Kruskal-Wallis-Test 137
a. Berechnung der Teststatistik 137
b. Post-hoc-Analyse 139
c. Schlussfolgerung 143
2. Chi-Quadrat-Test auf Unabhängigkeit 144
a. Berechnung der Teststatistik 146
b. Post-hoc-Analyse 148
c. Schlussfolgerung 152
3. Abgleich mit Studien 154
4. Annex zur Haftungsbeschränkung 156
III. Unternehmensnachfolge 160
1. Kruskal-Wallis-Test 160
2. Chi-Quadrat-Test 163
3. Schlussfolgerung 164
4. Abgleich mit Studien 165
IV. Beratung 166
1. Chi-Quadrat-Test 167
2. Schlussfolgerung 169
3. Abgleich mit Studien 170
V. Rechtsformwechsel 173
1. Mann-Whitney-U-Test 174
2. Chi-Quadrat-Test zu Rechtsformwechsel und Rechtsformkriterien 178
3. Chi-Quadrat-Test zu Rechtsformwechsel und Rechtsform 180
4. Chi-Quadrat-Test zu Gründungskosten und Rechtsform 181
5. Schlussfolgerung 184
6. Abgleich mit Studien 186
VI. Kriterien der Rechtsformwahl 188
1. Einführung zur explorativen Faktorenanalyse 188
a. Grundbegrifflichkeiten 191
(1) Kovarianz und Korrelation 191
(2) Varianz 192
(3) Eigenwert und Varianzanteil 196
(4) Kommunalität und Faktorladung 197
(5) Fehlervarianz, spezifische Varianz und Messfehler 200
(6) Reliabilität und Validität 202
b. Verfahrensschritte 203
(1) Extraktionsmethode 204
(2) Kommunalitätenproblem 205
(3) Faktorenauswahl 207
(4) Rotationsmethode 209
(5) Interpretation 212
2. Durchführbarkeit 214
a. KMO-Koeffizient 214
b. MSA-Koeffizient 215
c. Bartlett-Test 216
3. Berechnung 218
a. Extraktionsmethode 218
(1) Zielstellung 220
(2) Theoretischer Hintergrund 221
(3) Ergebnisvarianz 222
(4) Fehlerkonzept 223
b. Faktorenauswahl 225
(1) Kaiser-Guttman-Kriterium 225
(2) Scree-Test 227
(3) Parallelanalyse 229
(4) MAP-Test 230
(5) Theoriegeleitete Anzahl 231
(6) Gesamtschau 231
(7) Rotationsmethode 232
4. Interpretation und Schlussfolgerung 235
a. Interpretationsvorschlag 236
b. Alternativvorschlag 238
c. Erweiterte Darstellung der Strukturmatrix 240
d. Schlussfolgerung 244
(1) Erster Faktor 245
(2) Zweiter Faktor 246
(3) Dritter Faktor 247
(4) Gesamtschau 248
e. Abgleich mit Studien 249
E. Zusammenfassung, Thesen 251
Abkürzungsverzeichnis VII
Literaturverzeichnis IX
Danksagung XXXI
Anhang XXXII
Evaluating the representation of Arctic cirrus solar radiative effects in the Integrated Forecasting System with airborne measurements
No full textIn two case studies, airborne measurements of broadband solar irradiances above and below Arctic cirrus are compared to simulations of the Integrated Forecasting System (IFS) operated by the European Centre for Medium-Range Weather Forecasts (ECMWF) using offline runs of ECMWF's operational radiation scheme, “ecRad”. Furthermore, independent of the solar irradiances, cirrus properties are derived from collocated airborne active remote sensing observations to evaluate the optical and microphysical parameterizations in ecRad. The data were collected in the central Arctic over sea ice (81–90° N) with instrumentation installed aboard the High Altitude LOng range research aircraft (HALO) during a campaign in March and April 2022. Among others, the HALO instrumentation included upward- and downward-looking pyranometers to measure broadband solar irradiances, a cloud radar, and a multi-wavelength water vapour differential absorption lidar. Extended horizontal flight legs above and below single-layer cirrus were performed. The solar radiation measurements are used to evaluate ecRad in two case studies of optically thin and thick cirrus, with an average transmissivity of 0.9 and 0.6, respectively. Different ice optics parameterizations optionally available in ecRad are applied to test the match between simulation and measurements. Furthermore, the IFS-predicted ice water content and ice effective radius are replaced by values retrieved with the radar and lidar. The choice of ice optics parameterizations does not significantly improve the model–measurement agreement. However, introducing the retrieved ice microphysical properties brings measured and modelled irradiances in closer agreement for the optically thin cirrus, while the optically thick cirrus case is simulated as too thick. It is concluded that the ice water content simulated by the IFS is realistic and that the mismatch between observed and simulated solar irradiances mostly originates from the assumed or parameterized ice effective radius
Cardiovascular and Vector-Cardiographic Effects of Articaine Anesthesia with Epinephrine
No full textThe aim was to investigate the vector-cardiographic effects in patients submitted to dental extraction under local anesthesia. Twenty-one patients aged 36.6 ± 12.4 years with a clinical and radiographic indication of mandibular or maxillary tooth extraction were enrolled. The intervention was a local or mandibular nerve block anesthesia with 4% articaine hydrochloride containing epinephrine (1 : 100,000; 40 mg/ml + 10 μg/ml). Blood pressure (BP), heart rate (HR), pulse wave transit time, and vector-cardiography data were recorded throughout 3 min before and 5 min after injection. QRS- and T-wave area under the curve (QRSAUC/TAUC) were calculated from the X/Y/Z QRS-vector or T-vector. T-wave amplitude (TAM), TAUC values, and diastolic BP decreased, and HR significantly increased 4 min after injection. A transient moderate HR drop and a corresponding small increase in TAM and TAUC immediately after the injection procedure may be explained by a decreased sympathetic tone due to psychological relief. In dental anesthesia, the systemic epinephrine effects are represented by a decrease in TAUC. These effects are most pronounced in the X- and Y-leads. The 3D determination of vector planes or amplitudes is a simple method to register the sympathetic tone in local anesthesia independently of possible effects on T-wave characteristics in single leads. In conclusion, T-wave determination may help to detect even small increases in systemic adrenaline concentration in case of accidental intravascular injection. At the same time, full rhythm and spatial ischemia control is provided
Hyperspectral Imaging Detects Clitoral Vascular Issues in Gender-Affirming Surgery
No full textThe aim of this study was to assess the efficacy of hyperspectral imaging (HSI) as an intraoperative perfusion imaging modality during gender affirmation surgery (GAS). The hypothesis posited that HSI could quantify perfusion to the clitoral complex, thereby enabling the prediction of either uneventful wound healing or the occurrence of necrosis. In this non-randomised prospective clinical study, we enrolled 30 patients who underwent GAS in the form of vaginoplasty with the preparation of a clitoral complex from 2020 to 2024 and compared patients’ characteristics as well as HSI data regarding clitoris necrosis. Individuals demonstrating uneventful wound healing pertaining to the clitoral complex were designated as Group A. Patients with complete necrosis of the neo-clitoris were assigned to Group B. Patient characteristics were collected and subsequently a comparative analysis carried out. No significant difference in patient characteristics was observed between the two groups. Necrosis occurred when both StO2 and NIR PI parameters fell below 40%. For the simultaneous occurrence of StO2 and NIR PI of 40% or less, a sensitivity of 92% and specificity of 72% was calculated. Intraoperatively, the onset of necrosis in the clitoral complex can be reliably predicted with the assistance of HSI