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Toward forest dynamics’ systematic knowledge: concept study of a multi-sensor visually tracked rover including a new insect radar for high-accuracy robotic monitoring
No full textForest dynamics research is crucial in understanding the global carbon cycle and
supporting various scales of forest decision-making, management, and
conservation. Recent advancements in robotics and computing can be
leveraged to address the need for systematic forest monitoring. We propose a
common autonomous sensor box platform that enables seamless data
integration from multiple sensors synchronized using a time stamp–based
mechanism. The platform is designed to be open-source–oriented, ensuring
interoperability and interchangeability of components. The sensor box, designed
for stationary measurements, and the rover, designed for mobile mapping, are
two applications of the proposed platform. The compact autonomous sensor
box has a low-range radar that enables high-detail surveillance of nocturnal
insects and small species. It can be extended to monitor other aspects, such as
vegetation, tree phenology, and forest floor conditions. The multi-sensor visually
tracked rover concept also enhances forest monitoring capabilities by enabling
complex phenology monitoring. The rover has multiple sensors, including
cameras, lidar, radar, and thermal sensors. These sensors operate
autonomously and collect data using time stamps, ensuring synchronized data
acquisition. The rover concept introduces a novel approach for achieving
centimeter-accuracy data management in undercanopy forest conditions. It
utilizes a prism attached to the rover, which an oriented robotic total station
automatically tracks. This enables precise positioning of the rover and accurate
data collection. A dense control network is deployed to ensure an accurate
coordinate transfer from reference points to the rover. The demonstrated
sample data highlight the effectiveness and high potential of the proposed
solutions for systematic forest dynamics monitoring. These solutions offer a
comprehensive approach to capturing and analyzing forest data, supporting
research and management efforts in understanding and conserving
forest ecosystems.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
Co-Delivery of Ylang Ylang Oil of Cananga odorata and Oxaliplatin Using Intelligent pH-Sensitive Lipid-Based Nanovesicles for the Effective Treatment of Triple-Negative Breast Cancer
No full textSmart pH-responsive niosomes loaded with either Oxaliplatin (Ox), Ylang ylang essential oil
(Y-oil), or co-loaded with both compounds (Ox-Y) (Ox@NSs, Y@NSs, and Ox-Y@NSs, respectively) were
formulated utilizing the thin film method. The developed nanocontainers had a spherical morphology
with mean particle sizes lower than 170 nm and showed negative surface charges, high entrapment
efficiencies, and a pH-dependent release over 24 h. The prepared pH-responsive niosomes’ cytotoxicity
was tested against the invasive triple-negative breast cancer (MDA-MB-231) cells, compared to free OX
and Y-oil. All niosomal formulations loaded with Ox and/or Y-oil significantly improved cytotoxic
activity relative to their free counterparts. The Ox-Y@NSs demonstrated the lowest IC50 (0.0002 �g/mL)
when compared to Ox@NSs (0.006 �g/mL) and Y@NSs (18.39 �g/mL) or unloaded Ox (0.05 �g/mL)
and Y-oil (29.01 �g/mL). In addition, the percentages of theMDA-MB-231 cell population in the late
apoptotic and necrotic quartiles were profoundly higher in cells treated with the smart Ox-Y@NSs
(8.38% and 5.06%) than those exposed to free Ox (7.33% and 1.93%) or Y-oil (2.3% and 2.13%) treatments.
Gene expression analysis and protein assays were performed to provide extra elucidation regarding
the molecular mechanism by which the prepared pH-sensitive niosomes induce apoptosis. Ox-Y@NSs
significantly induced the gene expression of the apoptotic markers Tp53, Bax, and Caspase-7, while
downregulating the antiapoptotic Bcl2. As such, Ox-Y@NSs are shown to activate the intrinsic pathway
of apoptosis. Moreover, the protein assay ascertained the apoptotic effects of Ox-Y@NSs, generating
a 4-fold increase in the relative protein quantity of the late apoptotic marker Caspase-7. Our findings
suggest that combining natural essential oil with synthetic platinum-based drugs in pH-responsive
nanovesicles is a promising approach to breast cancer therapy.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
Comparative functional analysis of the GPI-specific metallophosphoesterases Cdc1, Ted1 and Dcr2 from Saccharomyces cerevisiae
No full textDie Biosynthese von Glycosylphosphatidylinositol (GPI) und der Transport von GPI-verankerten
Proteinen vom ER zur Plasmamembran oder der Zellwand wird in Eukaryoten durch ein komplexes
Prozessierungs- und Sortierungsnetzwerk vermittelt, an dem mehr als 20 bekannte Enzyme beteiligt
sind. In der Bäckerhefe Saccharomyces cerevisiae katalysieren die Metallophosphoesterasen
(MPEs) Cdc1 zusammen mit Ted1 und Dcr2 zwei wesentliche Schritte der GPI-Anker Prozessie-
rung. In einem Schritt wird der Ethanolaminphosphat Rest der Mannose-2 (EtNP-2) des GPI-Kerns
durch Ted1 im ER entfernt. Dies ist eine Reaktion, die für den effizienten Export aus dem ER erfor-
derlich ist. Des Weiteren kann EtNP-2 auch durch Dcr2 im Golgi-Apparat entfernt werden. In ei-
nem weiteren Schritt entfernt das Golgi lokalisierte Cdc1 den EtNP Rest von Mannose-1 (EtNP-1)
des GPI-Kerns. Diese Reaktion ist mutmaßlich essentiell für die Sortierung von GPI-verankerten
Proteinen von der Plasmamembran zur Zellwand. Während die essentielle Funktion dieser drei En-
zyme bei der Proteinsortierung durch eine Vielzahl genetischer und zellbiologischer Experimente
aufgedeckt wurde, ist die spezifische Rolle der MPEs bei Zellwandstress oder Biofilmbildung noch
nicht im Detail untersucht. Zudem ist die strukturelle Grundlage für die spezifische Substraterken-
nung und -verarbeitung durch diese Enzyme weitgehend unbekannt.
Im ersten Teil dieser Arbeit wurden die spezifischen Funktionen der Gene CDC1, TED1 und DCR2
bezüglich Zellwandstress und Biofilmbildung untersucht. Hierzu wurden Hefestämme mit verschie-
denen Gendosen dem Wachstum unter verschiedenen Substanzen, die mit der Zellwand inteferieren
oder unter der Biofilmbildung untersucht. Die durchgeführten Untersuchungen deuten darauf hin,
dass Cdc1 spezifisch sensitiv gegenüber den Zellwand einlagernden Substanten Kongorot und Cal-
cofluorweiß ist, während Ted1 und Dcr2 Sensitivität gegenüber des β1-3-Glucansynthase-Inhibitors
Caspofungin zeigten. Diese Befunde lassen sich durch unterschiedliche Substratspezifitäten der drei
Enzyme erklären. Im Gegensatz dazu wurde keine spezifische Funktion der drei MPEs während der
Biofilmbildung beobachtet.
Im zweiten Teil dieser Arbeit wurde eine Struktur-basierte Analyse von Cdc1, Ted1 und Dcr2 durch-
geführt, um für die Enzymfunktion essentielle Reste zu identifizieren. Insgesamt wurden 30 bisher
unbekannte essentielle Reste identifiziert, die an der Bindung des Co-Faktors, der Substratbindung
oder der strukturellen Integrität der Enzyme beteiligt sein könnten. Zudem wurden insgesamt 15
weitere Reste gefunden, die für die volle Funktion der Proteine unter Zellwandstress erforderlich
sind.
III
Ziel des letzten Teils war es, eine Variante von Cdc1 mit einer Ted1-artigen Funktion zu erhalten,
um Reste zu identifizieren, die möglicherweise die Substratspezifität vermitteln. Mit Hilfe in vitro-
Evolution-basierten Ansatzes konnte eine Cdc1-Variante mit 33 mutierten Aminosäuren (Cdc1MORF)
isoliert werden, welche dazu in der Lage war, den Zn2+-abhängigen Wachstumsdefekt eines Hefes-
tammsohne Ted1 zu komplementieren, nicht aber den letalen Wachstumsphänotypen in gleichzeiti-
ger Abwesenheit von Ted1 und Dcr2. Dieser Befund deutet darauf hin, dass Cdc1MORF keine verän-
derte Spezifität für die Bindung und Prozessierung von EtNP-2 aufweist, sondern stattdessen eine
bisher unbekannte Funktion erworben haben könnte, die eine erhöhte Zn2+-Resistenz vermittelt. Al-
lerdings konnte auch gezeigt werden, dass Cdc1MORF nicht mehr dazu in der Lage war, den letalen
Wachstumsphänotypen eines Stammes ohne Cdc1 zu komplementieren. Durch eine Feinanalyse der
33 Mutationen konnte dieser Phänotyp zur Identifizierung weiterer funktioneller Reste von Cdc1
führen.
Insgesamt konnten im Rahmen dieser Arbeit strukturelle Hotspots auf der Oberfläche von GPI-spe-
zifischen MPEs identifiziert werden, die an der Bindung von Co-Faktoren, Substraten oder der
strukturellen Integrität der Enzyme beteiligt. Auch konnten Reste ermittelt werden, welche die ro-
buste Funktion unter Zellwandstress gewährleisten.AbstractAbstract
In eukaryotes, biosynthesis of glycosylphosphatidylinositol (GPI) and transport of GPI-anchored
proteins from the ER to the plasma membrane or the cell wall are mediated by a complex process-
ing and sorting network involving more than 20 known enzymes. In the budding yeast Saccha-
romyces cerevisiae, the metallophosphoesterases (MPEs) Cdc1 together with Ted1 and Dcr2 ca-
talyze two essential steps of GPI-anchor processing. In one step, the ethanolaminephosphate moiety
of mannose-2 (EtNP-2) of the GPI-core is removed by Ted1 in the ER, a reaction that is required for
efficient ER export. In addition, EtNP-2 can be removed by Dcr2 in the Golgi apparatus. In another
step, Golgi-localized Cdc1 removes the EtNP moiety from mannose-1 (EtNP-1) of the GPI-core, a
reaction that is thought to be essential for sorting of GPI-anchored proteins from the plasma mem-
brane to the cell wall. While a substantial body of genetic and cell biological evidence has unco-
vered the essential function of these three enzymes in protein sorting, potential specific roles of
these MPEs during cell wall stress or biofilm formation has not be investigated in detail. In addi-
tion, the structural basis for specific substrate recognition and processing by these enzymes is
largely unknown.
In the first part of this work, the specific functions of CDC1, TED1 and DCR2 genes during cell
wall stress and biofilm formation were investigated by gene dosage variation and exposure of re-
spective yeast strains to different cell wall perturbing agents or biofilm-inducing conditions. These
investigations indicate that Cdc1 is specifically sensitive against the cell wall perturbing agents
Congo red and Calcofluor white, while Ted1 and Dcr2 appear to be highly sensitive against the β1-
3-glucan synthase inhibitor Caspofungin. These findings can be explained by different substrate
specificities of the three enzymes. In contrast, no specific function of the three MPEs was observed
during biofilm formation.
In a second part, a structure-guided analysis of Cdc1, Ted1 and Dcr2 was performed, in order to
identify residues that are essential for function of the enzymes. In summary, a total of 30 previously
unknown essential residues were identified that could be involved in co-factor binding, substrate
binding or structural integrity of the enzymes. In addition, a total of 15 further residues were found,
which are required for full functionality of the proteins under cell wall stress.
In the last part, it was attempted to obtain a variant of Cdc1 with a Ted1-like function, in order to
identify residues that might confer substrate specificity. By employing an in vitro evolution-based
approach, a Cdc1 variant carrying 33 amino acids mutations (Cdc1MORF) could be isolated, which
I
was able to complement the Zn2+-dependent growth defect of a yeast strain lacking Ted1, but not the
lethal growth phenotype caused by the absence of both Ted1 and Dcr2. This finding suggests that
Cdc1MORF does not exhibit an altered specificity towards binding and processing of EtNP-2, but
might instead have acquired a so far unknown function conferring increased Zn2+-resistance. Impor-
tantly, however, Cdc1MORF was also not able to complement the lethal growth phenotype of a strain
lacking Cdc1. By performing a fine analysis of the 33 mutations, this phenotype enabled the identi-
fication of further residues essential for the functionality of Cdc1.
Taken together, this work identifies structural hotspots on the surface of GPI-specific MPEs that ap-
pear to be involved in co-factor binding, substrate binding or structural integrity of the enzymes as
well as residues that confer robust function under cell wall stress
Microstructure predicts non-motor outcomes following deep brain stimulation in Parkinson’s disease
No full textDeep brain stimulation of the subthalamic nucleus (STN-DBS) effectively treats motor and non-motor symptoms in advanced Parkinson’s disease (PD). As considerable interindividual variability of outcomes exists, neuroimaging-based biomarkers, including microstructural metrics, have been proposed to anticipate treatment response. In this prospective open-label study, we sought to detect microstructural properties of brain areas associated with short-term non-motor outcomes following STN-DBS. Thirty-seven PD patients underwent diffusion MRI and clinical assessments at preoperative baseline and 6-month follow-up. Whole brain voxel-wise analysis assessed associations between microstructural metrics and non-motor outcomes. Intact microstructure within specific areas, including the right insular cortex, right putamen, right cingulum, and bilateral corticospinal tract were associated with greater postoperative improvement of non-motor symptom burden. Furthermore, microstructural properties of distinct brain regions were associated with postoperative changes in sleep, attention/memory, urinary symptoms, and apathy. In conclusion, diffusion MRI could support preoperative patient counselling by identifying patients with above- or below-average non-motor responses.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
Safety perception in patients with advanced idiopathic Parkinson’s disease – a qualitative study
No full textBackground: A fundamental cornerstone of quality of healthcare is patient
safety, which many people with life-limiting illnesses feel is being compromised.
Perceptions of impaired safety are associated with the occurrence of psychological
distress and healthcare utilization. However, little is known about how people
with idiopathic Parkinson’s disease (iPD) perceive their own safety toward the end
of life. The aim of our study was therefore to investigate factors that influence the
perception of safety of patients with advanced iPD.
Methods: We conducted semi-structured interviews with a purposeful sample
of 21 patients with advanced iPD. Participants were recruited at the neurology
department of a tertiary care hospital in Germany between August 2021 and June
2022. Data were analyzed using reflexive thematic analysis.
Results: iPD-patients reported relevant impairment of their safety. While most
participants expressed safety concerns based on the manifestation of disease,
our analysis identified enablers and barriers to establishing safety in patients with
advanced iPD, in 10 additional domains: relationship to the disease, informedness,
self-perception, utilization of support and care structures, healthcare professionals
and structures, treatment, social interaction, social security, spirituality, and
environment.
Conclusion: This study provides new insights into safety perceptions of
patients with advanced iPD, which extend well beyond the physical realm. The
findings suggest that clinicians and policy makers should consider a holistic and
multidisciplinary approach to assessing and improving patients’ safety taking into
account the enablers and barriers identified in this study.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
IKEA Effect vs. Trophy Effect – An Experimental Comparison
No full textmer’s valuation of the product. These phenomena are called the IKEA and the trophy effect. We test both of them separately as well as combined and find that the trophy winner effect looms larger than the IKEA effect for inexpensive items, in our case paper planes. For more expensive products, in our case 3-D-puzzles, we find a trophy loser effect. Positive emotions of trophy winners drive our result for inexpensive products, whereas negative emotions of trophy losers drive our result for more expensive products. We discuss the implications of our findings
Directed Technical Change and Energy Intensity Dynamics: Structural Change vs. Energy Efficiency
No full textThis paper uses a model with Directed Technical Change to theoretically analyse observable heterogeneous energy intensity developments. Based on the empirical evidence, we decompose changes in aggregate energy intensity into structural changes in the economy (structural effect) and within-sector energy efficiency improvements (effciency effect). The relative importance of these effects is determined by energy price growth and sectoral productivities that drive the direction of technical change. When research is directed to the labour-intensive sector, the structural effect is the main driver of energy intensity dynamics. In contrast, the effciency effect dominates energy intensity developments, when research is directed to energy-intensive industries. Increasing energy price generally leads to lower energy intensities and temporal energy price shocks might induce a permanent redirection of innovation activities. We calibrate the model to empirical data and simulate energy intensity developments across countries. The results of our very stylised model are largely consistent with empirical evidence
Die Rolle der Omega-3-Fettsäuren in der Pathogenese des GDM
No full textIn der vorliegenden Arbeit wurde die Rolle der Omega-3-FS in Erythrozyten in der Pathogenese des GDM anhand des n3-Index und des n6/n3-Quotienten untersucht. Hierzu erfolgte die gaschromatographische-massenspektrometrische Analyse von FS in Erythrozyten, Supplementen sowie pflanzlichen Ölen.
Zunächst erfolgte die Etablierung einer Methode, die sich an Schober et al. orientierte. Die Proben wurden laborchemisch aufgearbeitet und nach Umesterung zu FAMEs mittels Triple Quad GC/MS-MS analysiert. 35 FS konnten so detektiert und ausgewertet werden. Vor Analyse der Proben erfolgte eine Methodenvalidierung. Dazu wurden eine zehnfache Aufarbeitung sowie zehnfache gaschromatographische Analyse durchgeführt.
Bei den Blutproben handelte es sich um 102 anonymisierte Proben schwangerer Probandinnen mit GDM sowie 102 anonymisierte Proben schwangerer Probandinnen ohne GDM. Es konnte ein signifikant niedrigerer Omega-3-Index ((EPA+DHA)/alle FS) und ein signifikant größerer n6/n3-Quotient bei Probandinnen mit GDM festgestellt werden. Außerdem lagen nach Auswertung der relativen FS-Ergebnisse eine signifikant größere ALA-Konzentration sowie ein signifikant größerer AA/DHA-Quotient bei Probandinnen mit GDM vor. Signifikante Unterschiede der Gesamt-Omega-3- und Gesamt-Omega-6-FS konnten nicht nachgewiesen werden.
Des Weiteren wurden sechs verschiedene im Handel erhältliche Fischöle sowie eine Algen- und eine EPA-Kapsel analysiert. Dabei zeigten sich große Unterschiede der FS-Zusammensetzung und der Omega-3-Indices. Der höchste Omega-3-Index lag bei der EPA-Kapsel mit 78,31% vor, wobei EPA mit 64,75% den größten Teil hieran einnahm. Weitere hohe Omega-3-Indices lagen bei den Fischölkapseln von Elevit® (65,49%), Femibion® (60,48%) und Orthomol® Natal (57,08%) vor. Die Algenkapsel Velnatal® plus wies mit 18,71% den geringsten Omega-3-Index auf. Die n6/n3-Quotienten variierten zwischen der Fischölkapsel Orthomol® Natal mit 0,07 und der Algenkapsel Velnatal®plus mit 1,06.
Unter den 11 analysierten pflanzlichen Ölen und Samen wiesen Lein- und Chiasamenöl den höchsten Omega-3-Anteil in Form von ALA auf. Der Gehalt an EPA und DHA betrug bei allen pflanzlichen Ölen mit Ausnahme von Hanföl 0%.
Omega-3-FS scheinen damit einen protektiven Effekt auf die Entwicklung eines GDM zu haben. Langfristiges Ziel ist es, FS-Biomarker, die mit GDM in Verbindung stehen, zu identifizieren und Referenzwerte für diese zu bestimmen. Anhand dieser Parameter können Risikogruppen ausgemacht und Ernährungsempfehlungen beschlossen werden. Es bedarf weiterer Studien, bei denen zusätzliche Informationen über die Probandinnen und deren Ernährungsweise erhoben werden. Auch bedarf es weiterer longitudinaler Studien, welche Veränderungen des Glucose- und Fettsäurestoffwechsels detektieren. Insbesondere aufgrund der weitreichenden Konsequenzen von GDM für Mutter und Kind sind Ursachenfindung und adäquate Prävention der Erkrankung unverzichtbar
The effect of early skin-to-skin contact after cesarean section on breastfeeding duration and development of atopic-allergic diseases
No full textIntroduction:
Breastfeeding to strengthen the immune system suggests allergy prevention as a possible option. The connection between breastfeeding and the development of atopic-allergic diseases is being discussed. The primary aim of this work was to investigate an association of the first early skin-to-skin contact following cesarean section with the development of atopic diseases within the 1st year of life.
Methods:
The present study was conducted as a bicentric prospective cohort study in central Germany with a 15-month recruitment period. Data collection was by telephone interviews with a follow-up of 12 months. The statistical evaluation procedure was based on a hierarchical test of the association of early skin-to-skin contact between mother and child with the two main outcome measures. The primary outcome is the duration of breastfeeding. The second outcome is the onset of atopic-allergic disease within the 1st year of life.
Results:
Mothers breastfed longer if they had skin-to-skin contact within the first 30 minutes postpartum [χ²(df=5) = 19.020, p=0.002], if they breastfed their newborns early immediately after birth (p<0.001), and if the first skin-to-skin contact lasted more than one hour [χ²(df=4) = 19.617, p<0.001]. Regarding atopic-allergic diseases, no significant effects of skin-to-skin contact were found in relation to disease development. Regarding breastfeeding, no significant effects of atopic-allergic diseases could be detected either.
Conclusions:
The results of this study reflect the benefits of skin-to-skin contact in the context of breastfeeding and atopic disease. The current scientific knowledge regarding skin contact and the development of atopic-allergic diseases should be extended and deepened.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
The Impact of Psychological Pressure and Psychological Traits on Performance – Experimental Evidence of Penalties in Handball
No full textOur handball penalty field experiment analyses the influence of psychological traits and pres-sure on individual performance in sequential tournaments. We use a short ABBA-sequence with four throws for each subject and observe an average score rate of 60% in our sample of amateur league players. On game level, we find a weak and insignificant first-mover advantage that becomes stronger and significant if we control for psychological traits and pressure. On shot level, we also find no significant first-mover advantage on average. However, confident individuals have a higher scoring rate in the role of player A and less confident individuals in the role of player B. Moreover, ceteris paribus, player A scores more goals than player B under tournament incentives. Whereas self-esteem increases the probability to throw a goal in our experiment, risk-taking reduces it