Gutenberg Open Science (Univ. Mainz)
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The evolution of chemical ordering and property in Fe1+xSe2 upon intercalation ratios
No full textIntercalation has been considered as an effective method to explore innovative two-dimensional (2D) materials and modify their properties. However, the relationship between intercalation concentration, structure, and property remains a largely uncharted territory, and the controllable synthesis of desired intercalated phases faces challenges. Here, a general intercalated rule for the effect of self-intercalation ratio on atomic arrangements is revealed. Then, the controllable synthesis of a series of Fe-intercalated 2D materials is realized. Scanning transmission electron microscopy illustrates that their intercalation structures undergo disordered/ordered/half-ordered/ordered transformation, which confirms the intercalated rule and proposes a new structure termed half-ordered intercalation. Notably, their magnetic and electrical properties can be significantly modulated by intercalation. Orderly intercalated nanoflakes possess room-temperature magnetism with composition-regulated magnetic domains. Moreover, Fe1.5Se2 and Fe1.6Se2 are scarce half-metallic materials showing different magneto-resistance behaviors. This work would guide the design and synthesis of new intercalated materials, and deepen the understanding of the relationship between structure and properties
Structural and dynamic characteristics of water in biological systems
Get PDFXIII, 103 Seiten ; Illustrationen, Diagramm
Raw data for "At the “Peak” of vis-to-UV upconversion : clear advantages of TIPS substituents for a biphenyl annihilator"
No full textSensitized triplet–triplet annihilation systems enable the efficient conversion of two low-energy photons from a low-intensity, noncoherent light source into one high-energy photon, opening avenues for diverse applications. The attachment of triisopropylsilylethynyl (TIPS-ethynyl) groups to aromatic compounds has led to the development of many annihilators with high upconversion quantum yields. Here, we synthesized a series of novel symmetrical biphenyls bearing silylethynyl substituents of varying sizes and evaluated them as annihilators in visible-to-UV upconversion systems. While all of these systems do not suffer from excimer formation issues, their upconversion performances differ significantly. Small substituents like trimethylsilylethynyl gave similar upconversion quantum yields (up to ~12 %) as the TIPS-ethynyl groups, but the larger triphenylsilylethynyl substituents reduce the achievable quantum yields by half, which is likely due to additional nonradiative loss channels arising from altered energies of higher excited triplet states. The UV emission of the novel annihilators is hypsochromically shifted by about 20 nm relative to that of the TIPS-naphthalene benchmark UV annihilator, thereby reaching a highly attractive spectral region for bond activation photochemistry. Using the most efficient annihilator, bTIPS-BP, we achieved blue-to-UV upconversion-driven release of fluorescein from a photocage. In the greater context of photon upconversion and in view of other recent reports on substituent effects, our results indicate that several chromophore-specific effects have to be understood for obtaining optimized systems.Experiment
Approaches towards averting a potential structural shortage of general practitioners : results of a quantitative survey on attitudes, experiences, and ideas from general practitioners in the Federal Republic of Germany
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Securing primary care poses a complex set of challenges for policymakers in national healthcare. The risk of a shortage in general practitioners raises the question as to which approach would make an effective contribution towards averting an impending healthcare shortage. There has been a lack of studies shedding light on how general practitioners pview various approaches towards securing long-term primary care, and which measures they support from their own professional experience. The aim of the study was to ascertain the opinions, attitudes, and experiences of general practitioners in securing primary care across the country. We ran a survey to ask GPs about strategies that they saw as promising or particularly pressing, how they viewed the current situation regarding the shortage of general practitioners, and what they saw as causes for any decline they had already seen in primary care.
Methods
Our survey conducted online addressed a total of 5,164 general practitioners interviewed between August 2023 and April 2024 (40% response rate). Apart from descriptive analysis, we used Student’s t-test for independent samples to determine significant differences between two groups. We also performed a factor analysis (Varimax rotation).
Results
Our respondents displayed a somewhat negative view of primary care development in Germany. Many general practitioners expressed concerns as to whether primary care would remain secure in the long term. Despite partial progress, respondents saw a great need for countermeasures in the coming years. Nearly half of the respondents at 44% saw a noticeable decrease in general practices in their local area. Physicians in small towns and rural communities were more than twice as likely to experience the healthcare shortage due to a decline in general practitioners compared to their colleagues in medium-sized and large cities (42% versus 19%, p<0.001). More than half at 55% reported declining attractiveness in primary care for young physicians, which they attributed to three problem areas: 1) Position of primary care within the healthcare system, 2) Requirements for foundational and continuing medical education, 3) Working conditions. Respondents especially advocated the following approaches toward securing primary care: Establishing a primary care system (88%), more intense promotion of interest in primary care with points of contact in foundational and continuing medical education, especially in accompanying longitudinal programmes (78%), reinforcing multi-professional outpatient care centres (62%), restructuring curricula (54%) and enrolment criteria for medical study courses (51%), and reforming general medical training (55%).
Conclusions
General practitioners have their own proposals and preferences to add to the existing assessments and expert opinions. General practitioners should be involved more consistently than before in planning, implementing, and evaluating measures towards stabilising primary care. Various modes of participation and collaboration exist to this end
Effects of gut-derived inflammation and oxidative stress on vascular dysfunction and arterial hypertension in experimental celiac disease
Get PDFZöliakie (CeD) wird zunehmend mit einem erhöhten kardiovaskulären Risiko in Verbindung gebracht. Klinische Studien weisen auf höhere Mortalitätsraten und eine Zunahme kardiovaskulärer Ereignisse bei Zöliakie-Patienten hin. Ziel dieser Arbeit war es, mithilfe des NOD-DQ8-Mausmodells die Auswirkungen aktiver und nicht-aktiver Zöliakie auf das Herz-Kreislauf-System zu untersuchen. Ein besonderer Fokus lag auf den zugrundeliegenden Mechanismen und beteiligten zellulären sowie molekularen Komponenten.
Die Ergebnisse zeigten eine erfolgreiche Induktion der Zöliakie im Mausmodell, gekennzeichnet durch eine Infiltration von Immunzellen und Kryptenhyperplasie im Dünndarm, was zu einem reduzierten Verhältnis aus Zottenhöhe und Kryptentiefe führte. Systemische Analysen ergaben signifikante gliadininduzierte Veränderungen, darunter ein erhöhter Blutdruck und gesteigerte Serumcholesterinwerte. Trotz nachweislich erhöhter Entzündungswerte und oxidativem Stress im Herzen konnten keine funktionellen Einschränkungen der Herzleistung festgestellt werden. Hingegen wurde im Aortengewebe eine deutliche Gefäßdysfunktion beobachtet, bedingt durch oxidativen und nitro-oxidativen Stress sowie eine vermehrte Infiltration myeloider Immunzellen. Die Analyse des Fettgewebes zeigte unterschiedliche Reaktionen: Das perivaskuläre Fettgewebe (PVAT) wies eine stärkere proinflammatorische Beteiligung auf als das epididymale Fettgewebe (EWAT). Im Gehirn konnte eine erhöhte Expression entzündungsrelevanter Gene nachgewiesen werden, was auf weitreichende systemische Entzündungsreaktionen hinweist. Ein Wechsel zu einer glutenfreien Diät führte innerhalb von zwei Wochen zu einer Normalisierung des Blutdrucks, der Gefäßfunktion und der oxidativen Stresswerte. Dies unterstreicht das Potenzial der diätetischen Intervention zur Umkehrung entzündungsbedingter Schäden. Die Analyse mittels Olink-Plasma-Proteomik identifizierte Interleukin-17A (IL-17A) als möglichen Schlüsselmediator, der intestinale Entzündungsprozesse mit systemischen und vaskulären Effekten verbindet. Diese Ergebnisse tragen zum Verständnis der Beziehung zwischen Zöliakie, systemischen Entzündungen und kardiovaskulären Komplikationen bei und verdeutlichen die Bedeutung einer frühzeitigen Diagnose sowie geeigneter diätetischer Maßnahmen zur Prävention solcher Folgeerkrankungen.147 Seiten ; Illustrationen, Diagramm
Influence of land cover change on atmospheric organic gases, aerosols, and radiative effects
Get PDFBiogenic volatile organic compounds (BVOCs) are emitted in large quantities from the terrestrial biosphere and play a significant role in atmospheric gaseous and aerosol compositions. Secondary organic aerosols (SOAs) resulting from BVOC oxidation affect the radiation budget both directly, through the scattering and absorption of sunlight, and indirectly, by modifying cloud properties. Human activities have extensively altered natural vegetation cover, primarily by converting forests into agricultural land. In this work, a global atmospheric chemistry–climate model, coupled with a dynamic global vegetation model, was employed to study the impacts of perturbing the biosphere through human-induced land use change, thereby exploring changes in BVOC emissions and the atmospheric aerosol burden. A land use scheme was implemented to constrain tree plant functional type (PFT) cover based on land transformation fraction maps from the year 2015. Two scenarios were evaluated: (1) one comparing present-day land cover, which includes areas deforested for crops and grazing land, with potential natural vegetation (PNV) cover simulated by the model, and (2) an extreme reforestation scenario in which present-day grazing land is restored to natural vegetation levels. We find that, compared to the PNV scenario, present-day deforestation results in a 26 % reduction in BVOC emissions, which decreases the global biogenic SOA (bSOA) burden by 0.16 Tg (a decrease of 29 %), while the total organic aerosol (OA) burden decreases by 0.17 Tg (a reduction of 9 %). On the other hand, the extreme reforestation scenario, compared to present-day land cover, suggests an increase in BVOC emissions of 22 %, which increases the bSOA burden by 0.11 Tg and the total OA burden by 0.12 Tg – increases of 26 % and 6 %, respectively. For the present-day deforestation scenario, we estimate a positive total radiative effect (aerosol + cloud) of 60.4 mW m−2 (warming) relative to the natural vegetation scenario, while for the extreme reforestation scenario, we report a negative (cooling) effect of 38.2 mW m−2 relative to current vegetation cover
Molecular simulations of enzymatic phosphorylation of disordered proteins and their condensates
Get PDFCondensation and aggregation of disordered proteins in cellular non-equilibrium environments are shaped decisively by enzymes. Enzymes called kinases phosphorylate proteins, consuming the chemical fuel ATP. Protein phosphorylation by kinases such as Casein kinase 1 delta (CK1δ) determines the interactions of neurodegeneration-linked proteins such as TDP-43. Hyperphosphorylation of TDP-43 by CK1δ may be a cytoprotective mechanism for neurons, but how CK1δ interacts with protein condensates is not known. Molecular dynamics simulations hold the promise to resolve how kinases interact with disordered proteins and their condensates, and how this shapes the phosphorylation dynamics. In practice, it is difficult to verify whether implementations of chemical-fuel driven coarse-grained simulations are thermodynamically consistent, which we address by a generally applicable and automatic Markov state modeling approach. In this work, we thus elucidate with coarse-grained simulations, drivers of how TDP-43 is phosphorylated by CK1δ and how this leads to the dissolution of TDP-43 condensates upon hyperphosphorylation
Vergleich der operativen Therapien per Laparotomie versus minimal-invasiver Hysterektomie bei Vorliegen eines Karzinoms des Corpus uteri am Klinikum Worms gGmbH
Get PDFV, 72 Seiten ; Illustrationen, Diagramm
Etablierung einer RT-qPCR Methode zur Quantifizierung von ausgewählten Angiogenese-assoziierten Faktoren und Immunmodulatoren im Chorion-Allantois-Membran Assay (CAM-Assay)
Get PDFX, 125 Seiten ; Illustrationen, Diagramm
Is it safe to omit any chest X-ray before removing the chest drain after elective, non-cardiac thoracic surgery? A single-center, retrospective, case–control study
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Every patient undergoing non-cardiac thoracic surgery will receive several chest X-rays through the perioperative period. The patient might receive a preoperative X-ray as a baseline as well as several X-rays before and after drain removal. This routine has several disadvantages, for the patient, the health care system and the medical staff. Purpose of this study was to examine if all X-rays before removal of the drain can be omitted.
Methods:
Two hundred fifty-five patients who underwent elective thoracic surgery were included in this retrospective analysis. Patients undergoing urgent procedures or empyema surgery, as well as patients with symptoms requiring further diagnostic measures or patients who required clamping of the drain before removal, were excluded.
Results:
Forty-five patients received an X-ray before removal of the drain, and 210 patients did not. The X-ray group developed significantly more minor complications than the no X-ray group. 46.7% of the X-rays before drain removal (X-ray group) were reported with abnormalities. However, these abnormalities never led to a change in patient care. Drainage time and postoperative hospital stay were significantly longer in the X-ray group.
Conclusions:
Omitting any X-ray between surgery and removal of the chest drain appears to be safe in our retrospective patient cohort. The proposed benefits of omitting the X-ray are very relevant for the health care system, the medical and nursing teams, and, more importantly, for the patients. Evidence suggests that X-ray of patients regularly do not exist. It is therefore reasonable to consider exploring this question in a formal prospective trial