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Biomechanical comparison of two plantar lapidus plating systems
No full textBackground:
Hallux valgus (HV) is a common forefoot deformity that often leads to foot pain and functional limitations, requiring surgical intervention when conservative treatments fail. Tarsometatarsal arthrodesis is a widely used procedure for severe HV deformities, with plantar plate fixation demonstrating superior biomechanical outcomes. However, the biomechanical equivalence of different plantar plate designs remains unclear. Specifically, there is a lack of biomechanical studies comparing how design variations affect load distribution, durability, and the risk of material failure postoperatively. This study aims to address this gap by evaluating the biomechanical performance of 2 commonly used plantar plate designs.
Methods:
This study involved a biomechanical analysis of 2 widely used plantar Lapidus plating designs: U-shaped plates and straight-shaped plates. A total of 20 fresh frozen cadaveric feet from 10 donors were included. The plates were assigned randomly to each specimen, and tarsometatarsal arthrodesis was performed according to the manufacturers’ guidelines. Mechanical testing was conducted using a universal testing machine, focusing on cyclic loading and maximum load capacity to assess the mechanical stability of each system. Cyclic loads were systematically applied in 4 increments, culminating in a ramp test to ascertain the maximum load to material failure.
Results:
Both the U-shaped and the straight-shaped plantar Lapidus plates demonstrated commendable mechanical stability under cyclic loading, with nearly no significant differences in stiffness across the 4 cyclic loading force cycles. In the maximum load capacity test, the straight-shaped plate showed a higher mean load capacity (540.6 N, SD = 36.09) compared with the U-shaped plate (446.6 N, SD = 91.32), with a statistically significant difference (P = .03) and a large effect size (Cohen d = 1.56).
Conclusion:
This biomechanical study demonstrated that both U-shaped and straight-shaped plantar Lapidus plating systems provided comparable mechanical performance under stepwise cyclic loading conditions. The straight-shaped plates showed a higher failure rate during cyclic loading but achieved a significantly greater maximum load capacity in the final load-to-failure test. In contrast, the U-shaped plates were more consistent under repeated loading, suggesting potential advantages in fatigue resistance. These findings may reflect a trade-off between repetitive load endurance and maximum load-bearing capacity. Although these results offer biomechanical insight into the design-specific behavior of 2 commonly used plantar plating systems, their clinical relevance should be interpreted with caution, given the limitations of cadaveric testing, the absence of biological bone healing, and small sample sizes. Further clinical and long-term outcome studies are needed to confirm whether the observed mechanical differences translate into meaningful differences in patient function or fusion success.
Level of Evidence:
Level V, preclinical biomechinal study
Impaired non-verbal auditory memory maintenance in schizophrenia : an ERP study
No full textIndividuals with schizophrenia (SZ) exhibit deficits in speech perception in noise, which are closely related to their abnormalities in auditory working memory (WM). Auditory WM, especially the non-verbal auditory WM, serves as a bridge between perception, action, and long-term memory, playing a crucial role in integrating sound sequences to facilitate auditory object perception and auditory scene analysis (ASA). Although considerable research has been conducted on auditory sensory memory and visual WM in schizophrenia, studies specifically addressing non-verbal auditory WM remain scarce. Therefore, this study recorded the behavioral performance and event related potentials of 36 SZ and 36 healthy controls (HC) during a modified non-musical tone-sequence delayed matching-to-sample task (DMTS). The results showed that, in the tone-sequence DMTS, SZ had not only lower accuracy but also slower reaction times compared to the HC. More importantly, during the retention period, the memory maintenance of SZ begins to decay rapidly from the mid-stage, manifested by a significantly reduction in the late sustained anterior negativity (SAN2). Meanwhile, the early sustained anterior negativity (SAN1) in patients showed a significant correlation with their general pathological symptoms. The pathological symptoms can be predicted by the SAN1 under load 4 condition. This study provides empirical evidence for the impairment of non-verbal auditory WM maintenance in schizophrenia, which is of significant importance for understanding the auditory dysfunction and ASA difficulties experienced by SZ
Die monotheistische Wende im Ḥimyar
No full textIn diesem Artikel präsentiere ich die Ergebnisse meiner Dissertation, die ich am 01. Dezember 2021 an der Friedrich-Schiller-Universität Jena im Fach Semitistik verteidigt habe. Zunächst werde ich die Hauptfragestellung vorstellen, gefolgt von einer Diskussion der verwendeten Quellen und der angewandten Modelle aus der Konversionsforschung. Anschließend werde ich die Ergebnisse meiner Analyse von Lexikon und Onomastikon ansprechen, und danach die historische Einbettung des Prozesses in die monotheistische Wende im Römischen und Sasānidischen Reich sowie in Aksum. Zum Schluss möchte ich einige zentrale Ergebnisse zusammenfassen.Elektronische Reproduktio
Leveraging a phased pangenome for haplotype design of hybrid potato
No full textThe tetraploid genome and clonal propagation of the cultivated potato (Solanum tuberosum L.) dictate a slow, non-accumulative breeding mode of the most important tuber crop. Transitioning potato breeding to a seed-propagated hybrid system based on diploid inbred lines has the potential to greatly accelerate its improvement3. Crucially, the development of inbred lines is impeded by manifold deleterious variants; explaining their nature and finding ways to eliminate them is the current focus of hybrid potato research. However, most published diploid potato genomes are unphased, concealing crucial information on haplotype diversity and heterozygosity. Here we develop a phased potato pangenome graph of 60 haplotypes from cultivated diploids and the ancestral wild species, and find evidence for the prevalence of transposable elements in generating structural variants. Compared with the linear reference, the graph pangenome represents a broader diversity (3,076 Mb versus 742 Mb). Notably, we observe enhanced heterozygosity in cultivated diploids compared with wild ones (14.0% versus 9.5%), indicating extensive hybridization during potato domestication. Using conservative criteria, we identify 19,625 putatively deleterious structural variants (dSVs) and reveal a biased accumulation of deleterious single nucleotide polymorphisms (dSNPs) around dSVs in coupling phase. Based on the graph pangenome, we computationally design ideal potato haplotypes with minimal dSNPs and dSVs. These advances provide critical insights into the genomic basis of clonal propagation and will guide breeders to develop a suite of promising inbred lines
Photo-thermoresponsive polypyrrole-crosslinked single-chain nanoparticles for photothermal therapy
No full textIrradiating a chromophore allows cancer diagnostics by photoacoustic (PA) imaging, but also causes transformation of light into thermal energy and so enables therapy by photothermal effects. Useful chromophores for photothermal therapy (PTT), such as nanoconfined oligomers and polymers, should not only display an excellent light-to-heat efficiency, but in addition must display biocompatibility and good water-solubility. We in this study have designed water-dispersible, nanocaged polypyrroles (PPy), embedded into single-chain nanoparticles (SCNP, sized 6.8 – 8.9 nm) displaying thermoresponsivity, so reaching largely increased PTT-effects. Such encaged PPy-SCNPs allow an efficient photothermal heat conversion reaching temperatures up to 85°C. In a parallelized 96-well-plate-design the PPy-SCNPs can effect an almost complete death of illuminated (cancer) cells at already low concentrations (0.001 mg/mL) with low radiant fluxes. The thermoresponsivity of the SCNPs, surrounding the PPy-chains, then responds to the photothermal heat, so creating a unique self-amplifying effect for photothermal therapy and photoacoustic imaging
Constant enzymatic in situ production of H₂O₂ for an Unspecific Peroxygenase by an L-amino acid oxidase
No full textUnspecific Peroxygenases have been the subject of a lot of research in the recent past as they offer opportunities for green hydroxylation reactions using hydrogen peroxide (H2O2) as donor. A striking problem of UPOs is their low stability against their own co-substrate H2O2. In order to prevent the deactivation, we developed an enzyme cascade with an l-amino acid oxidase (LAAO) to produce hydrogen peroxide in situ at a constant low concentration, aiming for much higher lifespan and therefore longer working time of the enzyme. This way, we are able to convert a variety of substrates with conversion rates up to 95%
"You're free from just a girl or a boy" : nonbinary children's understanding of their gender
No full textBackground: In recent years, research on gender diversity in early childhood has increased significantly. However, much of the published literature still focuses on children whose experiences align with binary gender norms, inadvertently excluding nonbinary experiences from analysis. Aims: We seek to explore how nonbinary children, aged five to eight, perceive and understand their gender modality and experiences. Methods: Nine American nonbinary children were interviewed using a semi-structured approach, which included two book readings, a drawing activity, and approximately 23 pre-determined questions. Inductive reflexive thematic analysis was utilized for developing, analyzing, and interpreting patterns across a qualitative dataset. All authors engaged in various aspects of reflexivity throughout the process, including personal, functional, and disciplinary reflexivity. Analysis: We constructed five themes, which were evident across the accounts of participating children. The first one, Being nonbinary has different meanings for different people, illustrates the diverse interpretations of nonbinary identities. Gender is hard to describe but my pronouns help me make sense of it, highlights the challenges of explaining gender, yet pronouns help participants lucidly put their and others’ gender into words. People can change their gender for good or just for a little while, reflect participants’ view of gender as dynamic and fluid. “I have the agency to decide who I am with a little help of others”: feeling, learning, choosing and telling, explores participants’ journey in adopting the label “nonbinary”. Lastly, Being nonbinary is both easy and hard: easy because I am myself, hard because of other people, depicts the multifaceted experiences of being nonbinary, from the affirmation to bullying. Discussion: In an era marked by a contentious political climate and ongoing debates about trans/nonbinary individuals, these young children defy conventional norms and establish themselves as active architects of their identity narratives, driven by their agency and self-determination
Architekturkonzept deterministischer Kommunikationsnetzwerke für die IT/OT-Konvergenz
No full textDie industrielle Fertigung steht vor der Herausforderung, immer komplexere und vernetz-
te Systeme zu betreiben, welche zur selben Zeit hohe Anforderungen an Zuverlässigkeit
und Sicherheit erfüllen müssen. Traditionelle Ansätze stoßen dabei zunehmend an ihre
Grenzen. Hier bietet die Einführung von Virtualisierungstechnologie eine vielversprechen-
de Lösung, wodurch jedoch zusätzliche Anforderungen an die Kommunikationsnetzwerke
gestellt werden.
Diese Arbeit entwickelt auf Basis dieser identifizierten Anforderungen spezifische Architektur-
bausteine für ein IT/OT-konvergiertes Kommunikationsnetzwerk. Fokus liegt dabei auf der
Erreichung von Determinismus, damit eine zuverlässige und echtzeitfähige Kommunikation
erreicht wird. Durch die Kombination von Mechanismen wie Paketduplizierung und Quality
of Service wird die Virtualisierung und Konsolidierung von Automatisierungsapplikationen
ermöglicht, was die Betreibbarkeit aufgrund der flexiblen und skalierbaren Infrastruktur
vereinfacht.
Das Ergebnis ist ein umfassendes Architekturkonzept, das die breite Nutzung von IT-
Technologien in der Automatisierungsdomäne ermöglicht. Repräsentative Versuchsaufbauten
und der Vergleich mit den definierten Anforderungen bestätigen die Validität des entwickelten
Konzepts.Industrial production is facing the challenge of operating increasingly complex and networked
systems, which at the same time have to meet high reliability and safety requirements.
Traditional approaches are increasingly reaching their limits. Here, the introduction of
virtualization technology offers a promising solution, which, however, places additional
demands on the communication networks.
Based on these identified requirements, architecture modules are developed for an IT/OT-
converged communication network. One focus is on achieving determinism in order to
achieve reliable and real-time capable communication. The combination of mechanisms such
as packet duplication and quality of service enables the virtualization and consolidation
of automation applications, which simplifies operability due to the flexible and scalable
infrastructure.
The result is a comprehensive architecture concept that enables the broad use of IT techno-
logies in the automation domain. Representative test setups and the comparison with the
defined requirements confirm the validity of the developed concept.Literaturverzeichnis: Seite 119-13
Just Transitions Beyond Silos: Toward Inclusive and Ethical Governance
Get PDFThis policy paper outlines pathways to recalibrate just transition research and governance, addressing inappropriate siloed approaches that overlook lived realities, impact and unintended consequences of regulation, as well as various forms of resistance. It advocates for inclusive, ethical governance to address the interconnected challenges of climate and societal transitions. The paper calls for interdisciplinary collaboration and context-sensitive frameworks that balance urgency with ecological sustainability, social equity and technological innovation, alongside ethical safeguards. Key themes include legal pluralism to navigate overlapping and often conflicting legal and governance frameworks, centering marginalised voices through knowledge diversity, and addressing power imbalances through ethical reflexivity. The recommendations prioritise participatory policymaking, auditing of legal pluralism and power dynamics, as well as strengthening global climate equity, to ensure inclusive ecosocial transitions.Das Just Transition Center ist ein Projekt der Martin-Luther-Universität Halle-Wittenberg und beschäftigt sich mit Übermorgen-Fragen für einen gerechten, nachhaltigen und klimaneutralen Übergang in der Strukturwandelregion Mitteldeutsches Revier. Dafür arbeiten 17 interdisziplinäre Forschungsteams und vier Revierscouts eng mit den Akteuren in der Fokusregion südliches Sachsen-Anhalt zusammen und entwickeln Lösungen und Strategien für die Transformationsgesellschaft
Entwicklung eines automatisierten Testsystems für 5G-Sicherheitstestfälle, inklusive Aufbau und Erprobung eines 5G-Campusnetzes
Get PDFDiese Masterarbeit befasst sich mit der Entwicklung eines automatisierten Testsystems zur Überprüfung sicherheitsrelevanter Funktionen in 5G-Netzwerken. Ziel war es, eine realitätsnahe und flexible Testumgebung auf Basis eines privaten 5G-Netzes zu schaffen. Hierfür wurden Open-Source-Komponenten wie Open5GS und srsRAN sowie Hardware wie der USRP B210 verwendet. Das Testsystem ermöglicht sowohl generische Sicherheitsprüfungen als auch spezifische Tests für zentrale 5G-Netzfunktionen wie AMF und SMF. Durch die Integration von Robot Framework, Wireshark und weiteren Tools konnten Testfälle effizient automatisiert und ausgewertet werden. Die Ergebnisse zeigen, dass das System potenzielle Schwachstellen zuverlässig identifiziert und somit einen wertvollen Beitrag zur Verbesserung der Netzwerksicherheit in 5G-Umgebungen leistet.Literaturverzeichnis: Seite 76-7