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Exploring aerosol-cloud interactions in liquid-phase clouds over eastern China and its adjacent ocean using the WRF-Chem–SBM model
No full textIn this study we explore aerosol–cloud interactions in liquid-phase clouds over eastern China (EC) and its adjacent ocean (ECO) using the WRF-Chem–SBM model with four-dimensional assimilation. The results show that our simulations and analyses based on each vertical layer provide a more detailed representation of the aerosol–cloud relationship compared to the column-based analyses which have been widely conducted previously. For aerosol activation, cloud droplet number concentration (Nd) generally increases with aerosol number concentration (Naero) at low Naero and decreases with Naero at high Naero. The main difference between EC and ECO is that Nd increases faster in ECO than EC at low Naero due to abundant water vapor, whereas at high Naero, when aerosol activation in ECO is suppressed, Nd in EC shows significant fluctuation due to strong surface effects (longwave radiation cooling and terrain uplift) and intense updrafts. Cloud liquid water content (CLWC) increases with Nd, but the increase rate gradually slows down for precipitating clouds, while CLWC increases and then decreases in non-precipitating clouds. Higher Nd and CLWC can be found in EC than in ECO, and the transition-point Nd value at which CLWC in non-precipitating clouds changes from increasing to decreasing is also higher in EC. Aerosol activation is strongest at moderate Naero, but CLWC increases relatively fast at low Naero. ECO cloud processes are more limited by cooling and humidification, whereas strong and diverse surface and atmospheric processes in EC allow intense cloud processes to occur under significant warming or drying conditions
Evaluating EEG neurofeedback in sport psychology: a systematic review of RCT studies for insights into mechanisms and performance improvement
No full textElectroencephalographic Neurofeedback Training (EEG NFT) aims to improve sport performance by teaching athletes to control their mental states, leading to better cognitive, emotional, and physical outcomes. The psychomotor efficiency hypothesis suggests that optimizing brain function could enhance athletic ability, indicating the potential of EEG NFT. However, evidence for EEG-NFT’s ability to alter critical brain activity patterns, such as sensorimotor rhythm and frontal midline theta—key for concentration and relaxation—is not fully established. Current research lacks standardized methods and comprehensive studies. This shortfall is due to inconsistent EEG target selection and insufficient focus on coherence in training. This review aims to provide empirical support for EEG target selection, conduct detailed control analyses, and examine the specificity of electrodes and frequencies to relation to the psychomotor efficiency hypothesis. Following the PRISMA method, 2,869 empirical studies were identified from PubMed, Science Direct, Web of Science, Embase, CNKI, and PsycINFO. Thirteen studies met the inclusion criteria: (i) proficient skill levels; (ii) use of EEG; (iii) neurofeedback training (NFT); (iv) motor performance metrics (reaction time, precision, dexterity, balance); (v) control group for NFT comparison; (vi) peer-reviewed English-language publication; and (vii) randomized controlled trial (RCT) design. Studies indicate that NFT can enhance sports performance, including improvements in shooting accuracy, golf putting, and overall motor skills, as supported by the psychomotor efficiency hypothesis. EEG NFT demonstrates potential in enhancing sports performance by optimizing performers’ mental states and psychomotor efficiency. However, the current body of research is hampered by inconsistent methodologies and a lack of standardized EEG target selection. To strengthen the empirical evidence supporting EEG NFT, future studies need to focus on standardizing target selection, employing rigorous control analyses, and investigating underexplored EEG markers. These steps are vital to bolster the evidence for EEG NFT and enhance its effectiveness in boosting sport performance
Early Outcomes of Two Large Mitral Valve Transcatheter Edge-to-Edge Repair Devices: A Propensity Score Matched Multicenter Comparison
No full textBackground/Objectives: Previous trials reported comparable results with PASCAL and earlier MitraClip generations. Limited comparative data exist for more contemporary MitraClip generations, particularly the large MitraClip XT(R/W). We aimed to evaluate acute and 30-day outcomes in patients undergoing mitral valve transcatheter edge-to-edge repair (M-TEER) with one of the large devices, either PASCAL P10 or MitraClip XT(R/W) (3rd/4th generation). Methods: A total of 309 PASCAL-treated patients were matched by propensity score to 253 MitraClip-treated patients, resulting in 200 adequately balanced pairs. Procedural, clinical, and echocardiographic outcomes were collected for up to 30 days, including subgroup analysis for mitral regurgitation (MR) etiologies. Results: PASCAL and MitraClip patients were comparable regarding age (80 vs. 79 years), sex (female: 45.5% vs. 50.5%), and MR etiology (degenerative MR: n = 94, functional MR [FMR]: n = 96, mixed MR: n = 10 in each group). Technical success rates were comparable (96.5% vs. 96.0%; p > 0.999). At discharge, the mean gradient was higher (3.3 mmHg vs. 3.0 mmHg; p = 0.038), and the residual mitral valve orifice area was smaller in MitraClip patients (3.0 cm2 vs. 2.3 cm2; p 0.999). Conclusions: Both M-TEER devices exhibited high and comparable rates of technical success and MR reduction to ≤2+. PASCAL may be advantageous in achieving MR reduction to ≤1+ in patients with FMR
Natural Experiments: Missed Opportunities for Causal Inference in Psychology
No full textKnowledge about causal effects is essential for building useful theories and designing effective interventions. The preferred
design for learning about causal effects is randomized experiments (i.e., studies in which the researchers randomly
assign units to treatment and control conditions). However, randomized experiments are often unethical or unfeasible.
On the other hand, observational studies are usually feasible but lack the random assignment that renders randomized
experiments causally informative. Natural experiments can sometimes offer unique opportunities for dealing with this
dilemma, allowing causal inference on the basis of events that are not controlled by researchers but that nevertheless
establish random or as-if random assignment to treatment and control conditions. Yet psychological researchers have
rarely exploited natural experiments. To remedy this shortage, we describe three main types of studies exploiting natural
experiments (standard natural experiments, instrumental-variable designs, and regression-discontinuity designs) and
provide examples from psychology and economics to illustrate how natural experiments can be harnessed. Natural
experiments are challenging to find, provide information about only specific causal effects, and involve assumptions that
are difficult to validate empirically. Nevertheless, we argue that natural experiments provide valuable causal-inference
opportunities that have not yet been sufficiently exploited by psychologists
Evaluation of the Blood Neutrophil-to-Lymphocyte Ratio (NLR) as a Diagnostic and Prognostic Biomarker in Dogs with Portosystemic Shunt
No full textRoutine blood parameters (e.g., the neutrophil-to-lymphocyte ratio, NLR) are
valuable tools for diagnosing inflammatory, infectious, and metabolic conditions. Dogs with con-
genital liver shunts show evidence of generalized inflammation and clinical signs that may overlap
with those of other diseases. Therefore, the potential diagnostic and prognostic value of blood cell
ratios, including the NLR, was investigated in 106 dogs with congenital liver shunts and compared
to two other disease groups. An association was detected between the blood NLR and systemic
inflammation but not with any characteristics of the liver shunt or clinical correlates. The NLR
could not distinguish the three disease groups, dogs with liver shunts that were either medically or
surgically treated, or dogs either with successful shunt surgery or those with surgical complications.
However, lower NLRs (<2.53) were predictive of dogs with liver shunt surgery requiring only one
PSS closure session rather than two consecutive surgeries. Thus, evaluating the blood NLR might
be clinically useful in dogs with liver shunts. Although this parameter may have little value in
distinguishing dogs with a liver shunt from dogs with other diseases, it appears to be predictive for
the number of surgical sessions required for shunt closure via ligation.The neutrophil-to-lymphocyte ratio (NLR) can help in assessing inflammatory diseases,
sepsis, and chronic hepatic conditions in humans. Dogs with congenital portosystemic shunts (PSSs)
have signs of generalized inflammation, and the clinical signs can overlap with other conditions,
including hypoadrenocorticism (HOC). Thus, the potential diagnostic and prognostic value of leuko-
cyte ratios as surrogate markers was assessed in a retrospective case–control study including 106 dogs
diagnosed with PSSs. The disease control groups were dogs with parenchymal hepatopathy (PH;
n = 22) or HOC (n = 31). In the PSS dogs, the blood NLRs were associated with the severity of
systemic inflammation but not with the shunt type, hepatoencephalopathy, systemic infection, or
hypoglycemia. The baseline NLRs did not differ between the three disease groups, between medically
and surgically treated PSS dogs, or between those with successful PSS ligation and dogs experiencing
peri-/post-surgical complications. However, dogs requiring two consecutive surgical interventions
had significantly higher NLRs, and an NLR of <2.53 distinguished dogs with successful shunt ligation
in one surgery from those requiring two consecutive surgeries for PSS closure. The blood NLR might
be a useful clinicopathologic variable in PSS, but its value in helping differentiate PSS from HOC
cases appears low. Integrating the NLR into a diagnostic algorithm may allow for a prediction of the
number of surgical interventions required
A cloud-by-cloud approach for studying aerosol–cloud interaction in satellite observations
No full textThe effective radiative forcing (ERF) due to aerosol–cloud interactions (ACIs) and rapid adjustments (ERFaci) still causes the largest uncertainty in the assessment of climate change. It is understood only with medium confidence and is studied primarily for warm clouds. Here, we present a novel cloud-by-cloud (C×C) approach for studying ACI in satellite observations that combines the concentration of cloud condensation nuclei (nCCN) and ice nucleating particles (nINP) from polar-orbiting lidar measurements with the development of the properties of individual clouds by tracking them in geostationary observations. We present a step-by-step description for obtaining matched aerosol–cloud cases. The application to satellite observations over central Europe and northern Africa during 2014, together with rigorous quality assurance, leads to 399 liquid-only clouds and 95 ice-containing clouds that can be matched to surrounding nCCN and nINP respectively at cloud level. We use this initial data set for assessing the impact of changes in cloud-relevant aerosol concentrations on the cloud droplet number concentration (Nd) and effective radius (reff) of liquid clouds and the phase of clouds in the regime of heterogeneous ice formation. We find a of 0.13 to 0.30, which is at the lower end of commonly inferred values of 0.3 to 0.8. The between −0.09 and −0.21 suggests that reff decreases by −0.81 to −3.78 nm per increase in nCCN of 1 cm−3. We also find a tendency towards more cloud ice and more fully glaciated clouds with increasing nINP that cannot be explained by the increasingly lower cloud top temperature of supercooled-liquid, mixed-phase, and fully glaciated clouds alone. Applied to a larger number of observations, the C×C approach has the potential to enable the systematic investigation of warm and cold clouds. This marks a step change in the quantification of ERFaci from space
Analytical Framework to Understand the Origins of Methyl Side-Chain Dynamics in Protein Assemblies
No full textSide-chain motions play an important role in understanding protein structure, dynamics, protein–protein, and protein–ligand interactions. However, our understanding of protein side-chain dynamics is currently limited by the lack of analytical tools. Here, we present a novel analytical framework employing experimental nuclear magnetic resonance (NMR) relaxation measurements at atomic resolution combined with molecular dynamics (MD) simulation to characterize with a high level of detail the methyl side-chain dynamics in insoluble protein assemblies, using amyloid fibrils formed by the prion HET-s. We use MD simulation to interpret experimental results, where rotameric hops, including methyl group rotation and χ1/χ2 rotations, cannot be completely described with a single correlation time but rather sample a broad distribution of correlation times, resulting from continuously changing local structure in the fibril. Backbone motion similarly samples a broad range of correlation times, from ∼100 ps to μs, although resulting from mostly different dynamic processes; nonetheless, we find that the backbone is not fully decoupled from the side-chain motion, where changes in side-chain dynamics influence backbone motion and vice versa. While the complexity of side-chain motion in protein assemblies makes it very challenging to obtain perfect agreement between experiment and simulation, our analytical framework improves the interpretation of experimental dynamics measurements for complex protein assemblies
Retrospektive Analyse der Gabe von Donorlymphozyteninfusionen bei Patienten nach allogener Blutstammzelltransplantation. Eine Betrachtung des Transplantationszentrums Leipzig von 2007-2018.
No full textEinleitung:
Die allogene Blutstammzelltransplantation (alloSCT) ist eine therapeutische Option bei vielen malignen wie nicht malignen hämatologischen Erkrankungen, welche eine immunologische Wirkung der Zellen des Spenders nutzt. Um diese immunologische Wirkung der alloSCT zu verstärken, wurde die Gabe von Donorlymphozyteninfusionen (DLI) entwickelt. Die Gabe von DLI kann im Nachgang der Transplantation entweder prophylaktisch (beispielsweise bei einer unzureichenden Remission vor alloSCT), präemptiv oder therapeutisch erfolgen. Obwohl mittlerweile etwa 1,5 Millionen alloSCT weltweit durchgeführt worden sind, bleibt die Datenlage zu DLI und insbesondere zu patientenseitigen und prozessseitigen Risikofaktoren unzureichend.
Methoden: Die Analyse von 97 Patienten beschreibt die Charakteristika sowie
Verläufe aller Patienten aus den Jahren 2007-2018, welche am Universitätsklinikum
Leipzig mit DLI behandelt wurden. Hierfür wurden die Patientenakten sowie die
Daten der Transplantationsdokumentation ausgewertet. Die Analyse erfolgte mit R
Software (Version 3.6.2) und SPSS (Version 27). Ergebnisse: Das mediane Gesamtüberleben (OS) in der Gesamtkohorte betrug 701 Tage nach Gabe der DLI. In unserer Analyse konnte wir zeigen, dass eine prophylaktische Gabe von DLI mit einem besseren progressionsfreien Überleben (PFS) als eine therapeutische Gabe im Rezidiv (1-Jahres-PFS 66% vs. 50%; p=0,02) vergesellschaftet ist. Patienten welche die DLI in kompletter Remission (CR) erhielten zeigten ein verbessertes PFS (60% vs.47% p=0.02). Hinsichtlich des OS zeigte sich kein Unterschied hinsichtlich der Umstände der Gabe (prophylaktisch vs. therapeutisch (p=0,90) oder des Remissionsstatus (p=0.15). In der multivariaten Analyse des PFS war ein höheres Alter (Alter >50 Jahre (a) im Trend mit einem schlechteren PFS assoziiert (HR 1,76; p=0,06). Bei der multivariaten Analyse des OS zeigt sich, dass die Patienten mit weiblichen Geschlecht bei einer therapeutische DLI-Gabe ein besseres OS hatten (männlich vs. weiblich; 77% vs. 92%; p=0,047). Schlussfolgerung: Unsere Daten zeigen, dass die prophylaktische Gabe der DLI sowie eine Gabe in CR mit einem besseren PFS vergesellschaftet sind. In unserer
Kohorte zeigt sich ein Vorteil des OS für weibliches Geschlecht. Die Subgruppenanalyse erbrachte keinen Unterschied der Parameter OS und PFS
hinsichtlich der Diagnosen myelodysplastische Neoplasie/akute myeloische Leukämie/ akute Leukämie (MDS/AML/AL) vs. nonMDS/AML/AL. Aufgrund der Seltenheit der Prozedur und der damit einhergehenden Interzentrumsvariabilität sollten diese Daten Anlass zur weiterführenden Analyse gepoolter Daten aus mehreren Zentren oder für prospektive multizentrische Studien geben.:Deckblatt
Zusammenfassung
Inhaltsverzeichnis
Abkürzungsverzeichnis
Tabellenverzeichnis
Abbildungsverzeichnis
Genderdisclaimer
1.Einleitung
1.1. Krankheiten
1.1.1. Akute myeloische Leukämie (AML)
1.1.2. Akute lymphatische Leukämie (ALL)
1.1.3. Non-Hodgkin-Lymphom (NHL)
1.1.4. Myeloproliferative Neoplasien (MPN)
1.1.5. Myelodysplastische Syndrome/Neoplasien (MDS)
1.2. Allogene Blutstammzelltransplantation
1.2.1. Allgemeines
1.2.1.1. Geschichte der alloSCT
1.2.1.2. Ablauf einer alloSCT
1.2.2. Transplantationsimmunologie
1.2.2.1. Allgemeines
1.2.2.2. Immunologische Grundlagen
1.2.2.3. Host-versus-Graft-Reaktion
1.2.2.4. Graft-versus-Tumor/Leukämie-Reaktion (GvT/GvL)
1.2.2.5. Graft-versus-Host-Reaktion
1.2.3. Konditionierung
1.2.3.1. Allgemeines
1.2.3.2. Myeloablative Konditionierung (MA)
1.2.3.3. Reduced Intensity Conditioning (RIC)
1.2.3.4. Nicht Myeloablative Konditionierung (NMA)
1.2.4. Spenderauswahl
1.2.4.1. Allgemeines
1.2.4.2. Matched Sibling Donor
1.2.4.3. Matched Unrelated Donor
1.2.4.4. Missmatched Unrelated Donor
1.2.4.5. Haploidente Transplantation
1.2.4.6. Syngene Transplantation
1.2.5. Transplantatquelle
1.2.5.1. Allgemeines
1.2.5.2. Stammzellen des Knochenmarks (BM)
1.2.5.3. Periphere Blutstammzellen (PBSCT)
1.2.5.4. Stammzellen aus Nabelschnurblut (UCB)
1.2.6. Remissionsstatus nach alloSCT
1.2.6.1. Allgemeines
1.2.6.2. Chimärismus
1.2.6.3. Messbare Resterkrankung (MRD)
1.2.6.4. Bildgebung
1.2.7. Rezidivtherapie nach alloSCT
1.2.7.1. Allgemeines
1.2.7.2. Pharmakologische Therapie
1.2.7.3. Strahlentherapie
1.2.7.4. Immunologische Therapie nach alloSCT
1.2.7.4.1. Allgemeines
1.2.7.4.2. DLI bei CML
1.2.7.4.3. DLI bei AML
1.2.7.4.4. DLI bei ALL
1.2.7.4.5. DLI bei NHL
1.2.7.4.6. DLI bei anderen Entitäten
2. Aufgabenstellung
3. Patienten und Methoden
3.1. Patientendaten
3.2. Daten zur Transplantation
3.3. Daten zur Donorlymphozyteninfusion
3.4. Definition der Konditionierungstherapie
3.5. Klassifikation der Erkrankungen
3.6. Definition von Remission/Rezidiv
3.6.1. Definition von Remission/Rezidiv AML/MDS
3.6.2. Definition von Remission/Rezidiv: ALL
3.6.3. Definition von Remission/Rezidiv: NHL
3.6.4. Definition von Remission/Rezidiv: CML
3.6.5. Definition von Remission/Rezidiv: PMF
3.7. Klassifikation der GvHD
3.8. Definition der Art der DLI (prophylaktisch vs. therapeutisch)
3.9. Statistische Methoden
4. Ergebnisse
4.1. Patientencharakteristika
4.1.1. Demografische Daten
4.1.2. Daten zur alloSCT
4.1.3. Daten zur DLI Gabe
4.1.4. Daten zum Therapieergebnis
4.2. Vergleich der prophylaktischen und therapeutischen Kohorte
4.3. Ergebnisse der prophylaktischen Korhorte
4.3.1. PFS der prophylaktischen Kohorte
4.3.2. OS der prophylaktischen Kohorte
4.4. Ergebnisse der therapeutischen Kohorte
4.4.1. PFS der therapeutischen Kohorte
4.4.2. OS der therapeutischen Kohorte
4.5. Ergebnisse der MDS/AML/AL vs. nonMDS/AML/AL-Kohorte
4.6. Ergebnisse der AML vs. nonAML-Kohorte
4.7. Ergebnisse der prophylaktischen und therapeutischen Kohorte
innerhalb der „AML“-Subgruppe
4.8. Ergebnisse der CR vs. non CR-Kohorte
4.9. Ergebnisse der prophylaktischen und therapeutischen Kohorte
4.10. Ergebnisse der prophylaktischen und therapeutischen Kohorte
innerhalb der CR-Subgruppe
4.11. Ergebnisse der prophylaktischen und therapeutischen Kohorte
innerhalb der nonCR-Subgruppe
5. Diskussion
6. Zusammenfassung
7. Referenzen/Literatur
8. Erklärung über den Anteil an der Promotionsarbeit
9. Erklärung über die eigenständige Abfassung der Arbeit
10. Lebenslauf
11. Publikationen
12. Danksagun
Evaluation of methods to determine the surface mixing layer height of the atmospheric boundary layer in the central Arctic during polar night and transition to polar day in cloudless and cloudy conditions
No full textThis study evaluates methods to derive the surface mixing layer (SML) height of the Arctic atmospheric boundary layer (ABL) using in situ measurements inside the Arctic ABL during winter and the transition period to spring. An instrumental payload carried by a tethered balloon was used for the measurements between December 2019 and May 2020 during the year-long Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition. Vertically highly resolved (centimeter scale) in situ profile measurements of mean and turbulent parameters were obtained, reaching from the sea ice to several hundred meters above ground.
Two typical conditions of the Arctic ABL over sea ice were identified: cloudless situations with a shallow surface-based inversion and cloudy conditions with an elevated inversion. Both conditions are associated with significantly different SML heights whose determination as accurately as possible is of great importance for many applications. We used the measured turbulence profile data to define a reference of the SML height. With this reference, a more precise critical bulk Richardson number of 0.12 was derived, which allows an extension of the SML height determination to regular radiosoundings. Furthermore, we have tested the applicability of the Monin–Obukhov similarity theory to derive SML heights based on measured turbulent surface fluxes. The application of the different approaches and their advantages and disadvantages are discussed