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Graphene oxide-graft-poly(2-(dimethylamino)ethyl methacrylate) as a functional additive for structurally tuned and high-performance thin-film composite membranes
Get PDFForward osmosis (FO), a pressure-free membrane process, holds significant promise for water purification and seawater desalination. However, its efficiency is often limited by internal concentration polarization (ICP). To address this challenge, high-performance thin-film nanocomposite (TFN) membranes were developed by modifying poly(ethersulfone) (PES) substrates with varying amounts of graphene oxide-graft-poly(2-dimethylaminoethyl methacrylate) (GO-g-PDMA) nanoplates. The PDMA polymer is synthesized via atom transfer radical polymerization (ATRP) and covalently grafted onto azide-functionalized GO via click chemistry. This study systematically investigates the effects of GO-g-PDMA loading on substrate morphology, polyamide (PA) active layer formation, and overall membrane performance. Compared to bare GO, GO-g-PDMA significantly enhances the PES substrate's hydrophilicity, porosity, and water permeability. The optimally loaded TFN membrane (0.5 wt% GO-g-PDMA) exhibits superior FO performance, achieving water fluxes of 27.8 ± 1.9 L m−2 h−1 (LMH) in FO mode and 52.1 ± 1.5 LMH in PRO mode. Importantly, this membrane also demonstrates a 53.4% reduction in the structural parameter (S) relative to the unmodified TFC membrane, underscoring its improved resistance to ICP. These findings highlight the potential of GO-g-PDMA-functionalized substrates for enhancing FO membrane performance through synergistic improvements in the structure and function
Do dental students need sonography training? A prospective observational study
Get PDFIntroduction
Sonography is a key diagnostic tool in oral and maxillofacial surgery and complements other imaging methods such as computer tomography or X-rays. While X-ray courses are integral to dentistry students’ training, ultrasound diagnostics have not been integrated into undergraduate and postgraduate training. This study investigates whether there is a demand for undergraduate sonography training among dental students.
Methods
An online questionnaire was developed by a team of experts (dentistry, maxillofacial surgery, otorhinolaryngology, radiology, and didactics) based on the “Checklist for Reporting Results of Internet E-Surveys (Cherries)”. Multiple items addressed several topics using dichotomous (“yes”/ “no”), free text, and 7-level Likert answering formats (1 = not at all; 7 = fully and entirely). These included “personal data”, “previous experience”, “demand for ultrasound diagnostics in an undergraduate degree program”, “desired topics of ultrasound training”, “teaching methods”, and “study materials”. Dentistry students completed the questionnaire in the winter semester of 2023/24. The questionnaire’s validity was assessed using factor analysis, reliability testing (Cronbach’s Alpha, KR-20), and item discrimination.
Results
129 dental students participated (74% female). Many respondents (approx. 90%) were in higher semesters (6–10 semesters) and stated that they had not yet had any contact with ultrasound diagnostics (75%) and had not performed an ultrasound examination as yet (97%). The overall demand for ultrasound training was high (5.8 ± 1.3), particularly for the mandibular joint (6.3 ± 1.1), parotid gland (6.2 ± 1.0), submandibular gland, sublingual gland (6.1 ± 1.1), and floor of the mouth and tongue (5.9 ± 1.4) topics. Concerning the teaching methods and teaching materials, “practical training on a proband” (82%), and the use of “teaching scripts” (85%), “video instructions” (74%), “digital pathological experts” (66%), “e-learning” (62%), and “blended learning” (52%) were most desired. The questionnaire demonstrated high reliability (Cronbach’s Alpha 0.93–0.95), strong factor structure (84% and 64% variance explained), and effective item discrimination.
Conclusion
The data suggest a demand for undergraduate ultrasound training in dentistry. A practice-oriented, digitally supported training should be developed and implemented
Efficient manipulation of magnetic domain wall by dual spin-orbit torque in synthetic antiferromagnets
Get PDFCurrent-induced domain-wall motion (CIDWM) in a synthetic antiferromagnet is a key phenomenon for developing potential high-density-packed magnetic domain-wall memory with fast operation. Here, CIDWM is reported in the antiferromagnetically-coupled two Co layers through the Ir interlayer sandwiched by the two Pt layers: Pt/Co/Ir/Co/Pt. The top and bottom Pt layers play a role for generating the spin current coming from the spin Hall effect, which gives rise to the dual spin-orbit torque (SOT) acting on the perpendicular magnetizations of the Co layers. Although a simple argument would predict that SOTs from top and bottom Pt layers cancel each other out, the dual SOT nucleates a reversed magnetic domain and drives the CIDWM effectively at current density of the order of 1011 A m−2. This study also examines the effect of antisymmetric interlayer exchange coupling (AIEC) on CIDWM. A positive correlation between the magnitude of AIEC and the domain wall velocity is found, whereas the current density required for nucleating the reversed domain shows a negative correlation with the magnitude of AIEC. These facts suggest that the existence of AIEC improves the performance of CIDWM. The present results provide a new avenue to design SOT domain wall devices based on a synthetic antiferromagnet
Regulatory small RNA pathways in the nematode C. elegans and the ant T. rugatulus
Get PDFEpigenetic regulation via RNA interference (RNAi) is an important method for altering gene expression and for silencing transposons; transposable genetic elements which can self-insert into the genome at various locations, thus wreaking havoc on the genome when not kept in check. RNAi functions via proteins known as Argonautes which associate with small RNAs, using these to direct them to their targets via sequence complementarity. This thesis concerns different pathways related to RNAi in the nematode Caenorhabditis elegans, in which RNAi has long been studied, as well as in the ant, Temnothorax rugatulus, in which RNAi has not priorly been studied. In Chapter I, we show how the worm-specific Argonaute WAGO-3 is paternally inherited via the sperm in C. elegans, where it localizes to the newly found PEI-granule, whose phase-separation is controlled by the proteins PEI-1 and PEI-2. We show evidence to support the segregation into budding spermatids of PEI-1/2 and WAGO-3 via anchoring to fibrous body–membranous organelles (FB-MOs). We also show that WAGO-3 is important for paternal inheritance of transgenerational epigenetic memory (RNAe).
In Chapter II, we show that T. rugatulus expresses at least two different classes of small RNAs; miRNAs and piRNAs. We show that miRNAs are related to caste-differentiation and that the piRNA pathway, relevant for transposon silencing, is active even in rudimentary ovaries incapable of reproducing.
Finally, in Chapter III, we provide new insights into the functionalities of the three germline-expressed, worm-specific Argonautes WAGO-1, WAGO-3, and WAGO-4 in C. elegans. We show evidence that WAGO-1 and WAGO-4 influence the paternal ALG-3/4 pathway, possibly via interaction with the nuclear Argonaute WAGO-9/HRDE-1. WAGO-3, on the other hand, we find to influence the maternal ERGO-1 pathway, most likely also via interaction with one or more nuclear Argonautes. We find that Argonaute regulation depends on the lifestage of C. elegans, and we lastly show that mRNA misregulation caused by loss of WAGO-4 is
remembered transgenerationally.Epigenetisches Regulierung durch RNA Interferenz (RNAi) ist eine wichtige Methode um Genexpression zu beeinflussen und um Transposons zu unterdrücken. Transposons sind genetische Elemente die sich selbst an verschiedene Orte des Genoms einfügen können, und dabei das Genom zerstören, wenn sie nicht kontrolliert werden. RNAi funktioniert durch Proteine, sogenannte Argonauten, der mit Small RNAs interagieren und diesen benutzten, um ihre Ziele durch Sequenzkomplementarität zu finden. Dieser Dissertation betrifft verschiedene Pathways bezogen auf RNAi in der Nematode Caenorhabditis elegans, bei dem RNAi schon lange studiert wurde, sowie in die Ameise Temnothorax rugatulus, bei der RNAi nicht zuvor studiert wurde.
In Kapitel I zeigen wir wie der wurmspezifischen Argonaut WAGO-3 paternal durch die Spermien in C. elegans geerbt wird. Hier lokalisiert es sich auf dem neu entdeckten PEI-Granulum, dessen Phasentrennung durch die Proteine PEI-1 und PEI-2 kontrolliert wird. Wir zeigen Beweise, die die Segregation von PEI-1/2 und WAGO-3 in budding Spermatiden durch Verankerung an Fibrous Body-Membranous Organellen (FBMOs) unterstützen. Wir zeigen, dass WAGO-3 wichtig für paternaler Erbe vom transgenerationelles epigenetisches Gedächtnis ist.
In Kapitel II zeigen wir, dass T. rugatulus mindesten zwei verschiedenen Klassen von Small RNAs exprimieren; miRNAs und piRNAs. Wir zeigen, dass miRNAs mit der Kastendifferenzierung zusammenhängen, und dass das piRNA Pathway, die für Transposon-unterdrückung notwendig ist, sogar in rudimentären Eierstöcken, die sich nicht reproduzieren können, aktiv ist.
Schließlich geben wir in Kapitel III neue Einblicke in die Funktionalitäten der drei in der Keimbahn exprimierten wurmspezifischen Argonauten WAGO-1, WAGO-3 und WAGO-4 in C. elegans. Wir zeigen Evidenz dafür, dass WAGO-1 und WAGO-4 mit der paternalen ALG-3/4 Pathway interagieren, möglicherweise durch Interaktion mit der nuklearen Argonaut WAGO-9/HRDE-1. Anderseits finden wir, dass WAGO-3 mit der maternalen ERGO-1 Pathway interagiert, höchstwahrscheinlich auch durch Interaktion mit einen oder mehreren nuklearen Argonauten. Wir stellen fest, dass Argonaut-regulierung vom Lebensstadium von C. elegans abhängig ist, und zeigen schließlich, dass Fehlregulierung von mRNAs, die durch Verlust von WAGO-4 verursacht ist, transgenerationell erinnert wird.160, 2 Seiten ; Illustrationen, Diagramm
Attività economiche nell’ambito dei fiumi Teppia e Ninfa nel Quattrocento
Get PDFDie Studie beleuchtet die wirtschaftlichen Aktivitäten entlang der Flüsse Teppia und Ninfa im 15. Jahrhundert, einem Kernraum des nördlichen Agro Pontino unter der Herrschaft der Familie Caetani. Sie entstand im Kontext des von Michael Matheus initiierten und geleiteten internationalen und interdisziplinären Projektes zur Geschichte der Garten- und Ruinenstadt Ninfa und ihrer Umgebung vom Mittelalter bis ins 20. Jahrhundert: Ninfa: Das Pompeji des Mittelalters – FB 07 – Spätmittelalterliche Geschichte und Vergleichende Landesgeschichte. Auf Basis der Regesta Chartarum, der Imbreviaturen des Notars Antonio Tuzi aus Sermoneta (heute im Staatsarchiv Latina) und kartographischer Quellen aus dem Archivio Caetani in Rom wird die Topographie des Gebiets rekonstruiert und ihr Zusammenhang mit Verkehrs- und Wirtschaftsnetzen untersucht.
Die Flüsse dienten nicht nur als natürliche Grenzen, sondern auch als zentrale Ressourcen für Mühlenbetrieb, Bewässerung und eine umfangreiche Fischerei, die durch Verträge zwischen lokalen Grundbesitzern, Klöstern und in Velletri oder Rom ansässigen Händlern organisiert war. Ergänzend dazu bildeten Wege wie die Via Pedemontana und zahlreiche Brücken die Grundlage eines funktionierenden Agrarraums mit vielfältigen Nutzungsformen – von Weinanbau und Obstgärten bis zur Imkerei.
Die Untersuchung zeigt, dass die nördlichen Pontinischen Sümpfe im Spätmittelalter ein dynamisches Wirtschaftsgebiet waren, in dem natürliche Ressourcen und menschliche Aktivitäten in produktiver Wechselwirkung standen
In silico possibilities to understand peri-implant bone healing : state of the art
No full textPurpose
This scoping review was carried out to discover and compare all the possibilities the researchers have thought of in the recent past to perform in silico studies on bone healing after implantation of dental implants.
Methods
An electronic search was conducted in Pubmed, Web of Science, Science Direct and google scholar database to find out related articles in dental peri-implant healing simulations from the period of 2010 until 2025.
Results
In total, 40 articles were found relevant for this review. Different theories have been applied in the literature to simulate the mechanobiology of bone healing. Success has been found in predicting bone healing via in silico studies. The finite element was used often for these studies; however, the application of artificial intelligence is increasing with time in this sector.
Conclusions
In silico platforms provide a non-invasive and fast approach to study the bone healing process. They can be used as an aid to predict peri-implant bone healing in dentistry. The rise of artificial intelligence in this sector opens a new path, where these studies can be performed with high accuracy at an astounding fast pace. These methods can be a boon to clinicians, patients as well as implant developers
Impact of preoperative geriatric screening and comorbidity assessment in patients with vulvar and vaginal cancer
No full textPurpose
Patients with vulvar (VC) and vaginal (VaC) cancer are often frail and should be prescreened before a time-consuming comprehensive geriatric assessment (CGA). This study assessed the impact of the preoperatively determined frailty status with the G8 geriatric screening tool (G8) and comorbidity assessment on the outcome of patients with VC/VaC.
Methods
We conducted an observational study with prospective data collection of patients aged ≥ 60 undergoing surgery for VC and VAC from 05/2020 to 01/2025. Patients were assessed with the G8 tool, age-adjusted Charlson-Comorbidity Index and the Lee-index. Positive G8 results led to CGA-based testing and, if indicated, geriatric consultation. Cox regression, Kaplan–Meier curves and propensity score matching (PSM) were used to analyze the predictive validity of the G8.
Results
41 patients were screened. 26 patients were included with a mean follow-up of 23 months. 10 patients were considered G8 positive (G8 ≤ 14 points). Median age was 74.5 (interquartile range: 66–81.3) years. The G8 positive cohort was older, had more comorbidities and had higher ECOG and ASA performance status than the G8 negative cohort. 20% of the G8 positive patients did not receive standard surgical therapy and only one in five patients underwent standard adjuvant radio-/chemotherapy. The univariate Cox-model for overall survival (OS) for G8 positivity had a hazard ratio of 5.65 with 95% CI [1.14–28.1] and a significantly lower 2-year OS (40.0 vs. 85.1%), supported by PSM adjusted for residual confounding (p = 0.017).
Conclusions
The G8 can be easily implemented in the clinical routine to identify VC and VaC patients with a reduced 2-year OS who may benefit from CGA
Microphysical properties and thermodynamic phase of Arctic low-level clouds from in-situ aircraft measurements
Get PDFThe Arctic region is experiencing the most pronounced mean temperature rise of any region on Earth, causing drastic changes in the regional and global climate. Current investigations seek to elucidate the processes responsible for the intensified anthropogenic temperature change. Clouds in particular are suspected to play a crucial role in the Arctic climate feedback mechanisms. Clouds cool or warm the surface, depending on their ambient condition, microphysical properties, and thermodynamic phase. The gap in knowledge of microphysical cloud processes is particularly pronounced for mixed-phase clouds, which contain supercooled droplets with coexisting ice crystals and are frequently encountered in the lower part of the atmosphere at high latitudes. To better assess the role of clouds in the Arctic climate system, a comprehensive in-situ cloud data set of low-level Arctic clouds was measured within the scope of this thesis, using an advanced setup of airborne in-situ cloud probes.
The airborne in-situ cloud measurements were carried out over the northern Fram Strait between Greenland and Svalbard in spring 2019, summer 2020, and spring 2022. In total, 2676 min of low-level in-situ cloud observations were performed during 33 research flights above the sea ice and the open Arctic ocean with the research aircraft Polar 5 and Polar 6 of the Alfred Wegener Institute. At first, the in-situ cloud data from spring 2019 and summer 2020 are combined to investigate the distribution of particle number concentration N, effective diameter Deff, and cloud water content CWC (liquid and ice) of Arctic low-level clouds, measured at latitudes between 76 °N and 83 °N. A method is developed to quantitatively derive the occurrence probability of their thermodynamic phase from the combination of microphysical cloud probe and Polar Nephelometer data. The changes in cloud microphysics and cloud thermodynamic phase are investigated related to the ambient meteorological situation in spring and summer, and the effects of surface conditions, including sea ice or open ocean, on low-level clouds are revealed. A median N from 0.2 cm−3 to 51.7 cm−3 is found, with about two orders of magnitude higher N for mainly liquid clouds in summer compared to ice and mixed-phase cloud conditions measured in spring. A southward directed air mass flow from the sea ice in cold air outbreaks dominates cloud formation processes at temperatures below -10 °C in spring. In contrast, northward directed warm air intrusions favor the formation of liquid clouds at warmer temperatures in summer. The median CWC is higher in summer (0.16 g m−3) than in spring (0.06 g m−3), as this is dominated by the available atmospheric water content and the temperatures at cloud formation level. Significant differences in the particle sizes in spring and summer are observed, as well as an impact of the surface conditions, which modify the heat and moisture fluxes in the boundary layer. Analyses of the cloud thermodynamic phase show that the mixed-phase state is the dominant thermodynamic cloud phase in spring, with a frequency of occurrence of 61% over the sea ice and 66% over the ocean. In summer, the cloud particles are most likely in the liquid state.
In a subsequent study on Arctic low-level mixed-phase cloud conditions, the microphysical properties suggest a distinction between classic mixed-phase clouds and mixed-phase haze. The microphysical composition of this mixed-phase haze is similar to that of classic mixed-phase clouds. However, the supercooled droplets are replaced with large (> 2.8 µm) wet aerosol particles, and N is reduced by more than a factor of 150 in comparison to classic mixed-phase clouds. Further results show an increase of N in the atmospheric boundary layer over the sea ice compared to the open ocean, likely due to increased particle formation processes originating from the sea ice.
The results of this work enhance our understanding of the microphysical processes and thermodynamic phase composition of Arctic low-level clouds and will contribute to improve cloud parameterizations in climate and weather models. The findings will help to assess the role of low-level clouds in the Arctic radiation budget and to quantify their feedback mechanism in the region of the world with the strongest anthropogenic climate change.V, 158 Seiten ; Illustrationen, Diagramm
