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Effects of Different Hemoglobin Levels on Near-Infrared Spectroscopy-Derived Cerebral Oxygen Saturation in Elderly Patients Undergoing Noncardiac Surgery
No full textBackground: Near-infrared spectroscopy (NIRS) is a commonly used technique to evaluate tissue oxygenation and prevent harmful cerebral desaturation in the perioperative setting. The aims of the present study were to assess whether surgery-related anemia can be detected via NIRS of cerebral oxygen saturation and to investigate the effects of different perioperative transfusion strategies on cerebral oxygenation, potentially affecting transfusion decision-making. Study Design and Methods: Data from the ongoing multicenter LIBERAL-Trial (liberal transfusion strategy to prevent mortality and anemia-associated ischemic events in elderly noncardiac surgical patients, LIBERAL) were used. In this single-center sub-study, regional cerebral oxygenation saturation (rSO2) was evaluated by NIRS at baseline, pre-, and post-RBC transfusion. The obtained values were correlated with blood gas analysis-measured Hb concentrations. Results: rSO2 correlated with Hb decline during surgery (r = 0.35, p < 0.0001). Different RBC transfusion strategies impacted rSO2 such that higher Hb values resulted in higher rSO2. Cerebral desaturation occurred at lower Hb values more often. Discussion: Cerebral oxygenation monitoring using NIRS provides noninvasive rapid and continuous information regarding perioperative alterations in Hb concentration without the utilization of patients’ blood for blood sampling. Further investigations are required to demonstrate if cerebral rSO2 may be included in future individualized transfusion decision strategies
Progressive Multiple Alignment of Graphs
No full textThe comparison of multiple (labeled) graphs with unrelated vertex sets is an important
task in diverse areas of applications. Conceptually, it is often closely related to multiple sequence
alignments since one aims to determine a correspondence, or more precisely, a multipartite matching
between the vertex sets. There, the goal is to match vertices that are similar in terms of labels and
local neighborhoods. Alignments of sequences and ordered forests, however, have a second aspect
that does not seem to be considered for graph comparison, namely the idea that an alignment is
a superobject from which the constituent input objects can be recovered faithfully as well-defined
projections. Progressive alignment algorithms are based on the idea of computing multiple align-
ments as a pairwise alignment of the alignments of two disjoint subsets of the input objects. Our
formal framework guarantees that alignments have compositional properties that make alignments
of alignments well-defined. The various similarity-based graph matching constructions do not share
this property and solve substantially different optimization problems. We demonstrate that optimal
multiple graph alignments can be approximated well by means of progressive alignment schemes.
The solution of the pairwise alignment problem is reduced formally to computing maximal common
induced subgraphs. Similar to the ambiguities arising from consecutive indels, pairwise alignments
of graph alignments require the consideration of ambiguous edges that may appear between align-
ment columns with complementary gap patterns. We report a simple reference implementation in
Python/NetworkX intended to serve as starting point for further developments. The computational
feasibility of our approach is demonstrated on test sets of small graphs that mimimc in particular
applications to molecular graphs
Quantifying riming from airborne data during the HALO-(AC)3 campaign
No full textRiming is a key precipitation formation process in
mixed-phase clouds which efficiently converts cloud liquid to
ice water. Here, we present two methods to quantify riming
of ice particles from airborne observations with the normal-
ized rime mass, which is the ratio of rime mass to the mass of
a size-equivalent spherical graupel particle. We use data ob-
tained during the HALO-(AC)3 aircraft campaign, where two
aircraft collected radar and in situ measurements that were
closely spatially and temporally collocated over the Fram
Strait west of Svalbard in spring 2022. The first method is
based on an inverse optimal estimation algorithm for the re-
trieval of the normalized rime mass from a closure between
cloud radar and in situ measurements during these collocated
flight segments (combined method). The second method re-
lies on in situ observations only, relating the normalized rime
mass to optical particle shape measurements (in situ method).
We find good agreement between both methods during col-
located flight segments with median normalized rime masses
of 0.024 and 0.021 (mean values of 0.035 and 0.033) for the
combined and in situ method, respectively. Assuming that
particles with a normalized rime mass smaller than 0.01 are
unrimed, we obtain average rimed fractions of 88 % and 87 %
over all collocated flight segments. Although in situ measure-
ment volumes are in the range of a few cubic centimeters
and are therefore much smaller than the radar volume (about
45 m footprint diameter at an altitude of 500 m above ground,
with a vertical resolution of 5 m), we assume they are repre-
sentative of the radar volume. When this assumption is not
met due to less homogeneous conditions, discrepancies be-
tween the two methods result. We show the performance of
the methods in a case study of a collocated segment of cold-
air outbreak conditions and compare normalized rime mass
results with meteorological and cloud parameters. We find
that higher normalized rime masses correlate with streaks of
higher radar reflectivity. The methods presented improve our
ability to quantify riming from aircraft observation
Evaluation of a football fitness implementation initiative for an older adult population in a small-scale island society
No full textBackground: The proportion of older people increases globally, which calls for sustainable interventions promoting healthy aging. Therefore, we aimed to evaluate the potential of Football Fitness as a sustainable model to promote quality of life, mental health, and physical function for older adult.
Methods: The study was conducted in collaboration with a municipality, a football club, and a university, and was designed as a randomized controlled trial. A total of 66 people (34 women, 32 men) older than 60 years were randomly assigned (60/40) to a Football Fitness (FOT) (n = 38, 20 women, 18 men) and a control group (CON) (n = 28, 14 women, 14 men). FOT participated in Football Fitness for 12 weeks. Quality of life (QoL) and mental wellbeing were determined pre-and post-intervention. Physical loading and Flow experience were measured in one representative training session. Blood pressure (BP), Yo–Yo Intermittent endurance test level 1 (Yo–Yo IE1), sprint performance, postural balance, and body composition were also performed pre-and post-intervention.
Results: An improvement in mental wellbeing was observed for both groups from pre- to post-intervention (p values <0.001) with no between-group differences. Regarding QoL, the environment domain improved in FOT compared to CON (p = 0.02). Mean Flow (M = 5.69; SD = 1.07) and perceived importance (M = 4.20; SD = 1.42) and average experienced difficulty was M = 5.23 (SD = 2.67), perceived skill (M = 5.23; SD = 2.56), and perceived balance (M = 5.64; SD = 1.56). These levels of flow can be characterized as being high. A between-group effect (p = 0.02) existed for systolic BP, which decreased (p < 0.01) by −5% [−8; −1%] in CON and remained unchanged in FOT. Both groups improved the Yo–Yo IE1 to a similar extent, with 28% [11; 44%] (p = 0.001) in FOT and 27% [9; 46%] in CON (p = 0.005). Postural balance improved (p = 0.004) by 38% [13; 63%] in FOT only, resulting in a superior (p = 0.01) balance score in FOT compared to CON post-intervention (p = 0.004).
Conclusion: Football Fitness improved the environmental quality of life domain and postural balance in older adults. Additionally, it appears to be a feasible group activity for older adults that promotes high flow and physical loading during training
Entwicklung der Hämophiliebehandlung im Osten Deutschlands in den letzten 10 Jahren – eine Untersuchung des Kompetenznetz Hämorrhagische Diathese Ost (KHDO)
No full textIm Jahr 2005 hat das Kompetenznetz Hämorrhagische Diathese Ost epidemiologische Daten über Patienten im Osten Deutschlands mit Hämophilie A (HA) und B (HB) publiziert. Diese Studie liefert Daten über die Entwicklung der Hämophiliebehandlung bei diesen Patienten in den letzten 10 Jahren.
Methoden: Daten von 12 Hämophiliezentren im Osten Deutschlands aus dem Jahr 2015 wurden retrospektiv aus den Patientenakten ausgewertet.
Ergebnisse: Wir untersuchten 413 Patienten (115 Kinder, 298 Erwachsene) mit HA oder HB. 286 Patienten (69,2%) hatten eine schwere Hämophilie (PMSH). Im Vergleich zu 2005 ist der Anteil der PMSH mit Prophylaxe bei den Kindern von 90% auf 98.8% und bei den Erwachsenen von 64% auf 80,2% angestiegen. Der Verbrauch von plasmatischen Faktorenkonzentraten ist von >70% auf 55,3% bei Kindern und 55,1% bei Erwachsenen gesunken. Der mittlere Faktorenverbrauch bei PMSH ohne Hemmkörper war 2015 höher als 2005 (Kinder mit HA 151.489 versus 98.894, Erwachsene mit HA 217.151 versus 151.394, Kinder mit HB 105.200 versus 64.256, Erwachsenen mit HB 159.185 versus 85.295). Die mediane jährliche Blutungsrate und Gelenkblutungsrate in 2015 war 2 bzw. 0 bei Kindern und 3 bzw. 0 bei Erwachsenen. Im Jahr 2015 war lediglich ein Kind (1,2%) aber 101 (53,2%) Erwachsene mit schwerer Hämophilie anti-HCV positiv. Der Anteil der anti-HCV-positiven Erwachsenen mit aktiver Hepatitis C fiel von 63,8% auf 12,9%.
Zusammenfassung: In den letzten 10 Jahren wurden mehr Patienten auf eine prophylaktische Behandlung umgestellt. Dies geht mit einem moderaten Anstieg des Verbrauchs an Faktorenkonzentraten einher, resultiert aber in einer niedrigen Blutungsrate.:Inhaltsverzeichnis
1. Abkürzungsverzeichnis
2. Einleitung
2.1 Physiologie der Hämostase
2.2 Zellbasiertes Gerinnungsmodell
2.3 Hämophilie
2.3.1 Ätiologie und Epidemiologie
2.3.2 Grundlagen des Therapieregimes und Monitoring
2.3.3 Präparate
a) Historische Entwicklung und Therapiestandard
b) Weitere Therapieoptionen
c) Faktorenunabhängige Therapie
2.3.4 Komplikationen: Blutungsereignisse, Virale Infektionen, Hemmkörperentwicklung
a) Blutungsereignisse
b) Virale Infektionen
c) Hemmkörperentwicklung
3. Zielsetzung der vorliegenden Arbeit
4. Publikationsmanuskript
5. Zusammenfassung der Arbeit
6. Literatur
7. Anlagen
8. Darstellung des eigenen Beitrags
9. Erklärung über die selbstständige Verfassung der Arbeit
10. Lebenslauf
11. Verzeichnis der wissenschaftlichen Veröffentlichungen
12. Danksagun
Machine learning algorithms predict canine structural epilepsy with high accuracy
No full textIntroduction: Clinical reasoning in veterinary medicine is often based on
clinicians’ personal experience in combination with information derived from
publications describing cohorts of patients. Studies on the use of scientific
methods for patient individual decision making are largely lacking. This applies
to the prediction of the individual underlying pathology in seizuring dogs as
well. The aim of this study was to apply machine learning to the prediction of
the risk of structural epilepsy in dogs with seizures.
Materials and methods: Dogs with a history of seizures were retrospectively
as well as prospectively included. Data about clinical history, neurological
examination, diagnostic tests performed as well as the final diagnosis were
collected. For data analysis, the Bayesian Network and Random Forest algorithms
were used. A total of 33 features for Random Forest and 17 for Bayesian Network
were available for analysis. The following four feature selection methods were
applied to select features for further analysis: Permutation Importance, Forward
Selection, Random Selection and Expert Opinion. The two algorithms Bayesian
Network and Random Forest were trained to predict structural epilepsy using
the selected features.
Results: A total of 328 dogs of 119 different breeds were identified retrospectively
between January 2017 and June 2021, of which 33.2% were diagnosed with
structural epilepsy. An overall of 89,848 models were trained. The Bayesian
Network in combination with the Random feature selection performed best.
It was able to predict structural epilepsy with an accuracy of 0.969 (sensitivity:
0.857, specificity: 1.000) among all dogs with seizures using the following
features: age at first seizure, cluster seizures, seizure in last 24 h, seizure in last
6 month, and seizure in last year.
Conclusion: Machine learning algorithms such as Bayesian Networks and
Random Forests identify dogs with structural epilepsy with a high sensitivity and
specificity. This information could provide some guidance to clinicians and pet
owners in their clinical decision-making process
Road safety implications of the partial legalisation of cannabis in Germany: protocol for a quasi-experimental study
No full textIntroduction Germany is reforming its legal approach to cannabis, allowing the possession and cultivation of cannabis for recreational purposes. The objective of this study is to investigate the impact of the policy reform on (1) The prevalence of cannabis use in the general population and (2) Driving under the influence of cannabis (DUIC) among regular users.
Methods and analysis A quasi-experimental research design will be employed, with repeated cross-sectional surveys on self-reported DUIC and cannabis use conducted at three measurement points in Germany (intervention group) and Austria (control group) over a 2-year observation period (2023–2025). Data will be collected from approximately 50 000 individuals aged between 18 years and 64 years. To minimise reporting biases in the measurement of DUIC, we will use direct and indirect assessments via crosswise model and motor vehicle accident data from official statistics. In a difference-in-difference framework, regression analyses and interrupted time series analysis will be carried out for hypothesis testing.
Ethics and dissemination Participants will be informed about voluntary participation, data protection laws and the option to delete data on request. Ethical approval was obtained from the Local Psychological Ethics Committee of the Centre for Psychosocial Medicine in Hamburg, Germany (reference number: 0686). Findings will be disseminated through scientific networks and will be key for a comprehensive evaluation of the cannabis law reform. The findings will facilitate the design and implementation of road safety measures
Myocardial injury and clinical outcome in octogenarians after non–ST-elevation myocardial infarction
No full textIntroduction: The aim of this study was to analyze age-associated myocardial
injury and clinical outcome after non-ST-elevation myocardial infarction (NSTEMI).
Methods: This prospective, multicenter study consists of 440 patients with
NSTEMI enrolled at 7 centers. All patients were treated with primary
percutaneous coronary intervention and underwent cardiac magnetic
resonance (CMR) imaging 1–10 days after study inclusion. CMR parameters
of myocardial injury and clinical outcome were evaluated by creating
2 subgroups: <80 years vs. ≥80 years. The clinical endpoint was the 1-year
incidence of major adverse cardiac events (MACE) consisting of death,
re-infarction and new congestive heart failure.
Results: Elderly patients ≥80 years accounted for 13.9% of the study population
and showed a divergent cardiovascular risk profile compared to the subgroup of
patients <80 years. CMR imaging did not reveal significant differences regarding
infarct size, microvascular obstruction, left ventricular ejection fraction or
multidimensional strain analysis between the study groups. At 1-year follow-
up, MACE rate was significantly increased in patients ≥80 years compared to
patients aged <80 years (19.7% vs. 9.6%; p = 0.019). In a multiple stepwise
logistic regression model, the number of diseased vessels, aldosterone
antagonist use and left ventricular global longitudinal strain were identified as
independent predictors for MACE in all patients, while there was no
independent predictive value of age regarding 1-year clinical outcome.
Conclusion: This prospective, multicenter analysis shows that structural and
functional myocardial damage is similar in younger and older patients with
NSTEMI. Furthermore, in this heterogeneous but also clinically representative
cohort with reduced sample size, age was not independently associated with
1-year clinical outcome, despite an increased event rate in patients ≥80 years
The recent turn in analytical sociology: The dismissal of general theories, mental states, and analytic philosophy – and the old issue of mechanism explanations
No full textAnalytical sociology is a sociological approach whose advocates share two methodological doctrines: sociology should be a rigorous discipline and focus on action-based explanations of social processes. This article analyzes some recent methodological innovations of analytical sociology: (1) it is proposed to abandon general theories, in particular rational choice theory. We raise several objections against this claim. The major argument for applying general theories is that an empirical comparison with middle range theories implies conditions for their modification and at the same time tests the general theory. Another flaw of the critique of rational choice theory is that the target is not a wide ‘bounded rationality’ version that is increasingly applied in the social sciences. Instead, an outdated narrow version is attacked; (2) a new demand is to give up explanations with mental states such as goals and beliefs and focus on situational factors. It is argued that this leads to false explanations because the impact of situational factors on action depends on mental states. Omitting mental states thus leads to invalid explanations; (3) a major unresolved issue is the thesis that mechanism explanations are a special kind of explanation that do not need to apply theories. It is shown why this demand is mistaken
Acting from knowledge
No full textThis essay explores the idea of acting from knowledge. This
idea is a thought of ourselves: the distinctive way in which
we act, in which we live, resides in this, that our actions, our
life, may rest on knowledge. Yet the idea of action resting
on knowledge is puzzling, even mysterious. The difficulty
springs from the character of judgment that is knowledge:
its objectivity. The objectivity of a judgment is a character
of its validity: it is objectively valid. Yet it is equally, and
therefore, a character of the source of the reality of a valid
judgment: a judgment that is knowledge is explained by
nothing other than that which constitutes its validity. Now,
action from knowledge partakes of this character of the
knowledge on which it rests: it is explained by nothing other
than what constitutes its validity, that is, its goodness. This
dissolves the idea that action springs from a natural power,
a power of change, a physis. That is the mystery. What
could action be but the act of a natural power, and what
could we be but agents of such a power