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Gemischte Gefühle: Was bedeutet das neue „Whatever it takes“ für die deutschen Immobilienmärkte?
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Outcomes of biosynthetic collagen prostheses with comparison to cryopreserved arterial homografts for bypass reconstruction in infrainguinal vascular graft infections
Get PDFBackground and Aims: Managing infrainguinal vascular graft infections (VGI) in bypass
reconstruction is complex. Although an autologous vein is the preferred graft material, alternative
conduits are required when autologous veins are unavailable. This study aimed to compare the
efficacy of cryopreserved arterial homografts and biosynthetic glutaraldehydemodified
ovine collagen grafts (Omniflow II) for the treatment of infrainguinal VGI.
Methods: The study was retrospective across two centers and included patients with infrainguinal
VGI treated with cryopreserved arterial homografts or Omniflow II grafts between 2009 and 2019.
Freedom from reinfection, primary patency rates, amputation-free survival, and overall survival
were analyzed using 5-year Kaplan-Meier estimates.
Results: Overall, 63 patients with infrainguinal VGI were treated with either Omniflow II grafts
(n = 34) or cryopreserved arterial homografts (n = 29). At 5 years, freedom from reinfection was
97.1% for Omniflow II grafts and 93.1% for cryopreserved arterial homografts (p = .4). Primary
patency was 50% for Omniflow II grafts and 55.2% for the cryopreserved arterial homografts
(p = .5). Amputation-free survival was 52.9% for Omniflow II grafts and 55.2% for cryopreserved
arterial homografts (p = .7). No graft degeneration or graft ruptures were observed during the
follow-up.
Conclusions: This study suggests that biosynthetic grafts are viable and accessible alternatives
for traditional graft materials, offering similar efficacy and ease of use. Although autologous
vein grafts remain the gold standard for VGI management, biosynthetic grafts may serve as
a viable alternatives to cryopreserved arterial homografts in the treatment of infrainguinal
VGIs
Quantum Hall effect and current distribution in the three-dimensional topological insulator HgTe
Get PDFWe study the quantum Hall effect (QHE) in the three-dimensional topological insulator HgTe, which features topological Dirac-type surface states in a bulk gap opened by strain. Despite the coexistence of multiple carrier subsystems, the system exhibits perfectly quantized Hall plateaus at high magnetic fields. Here we study the system using three different experimental techniques: Transport experiments, capacitance measurements including the quantum capacitance, and current distribution measurements using electrostatically sensitive scanning probe microscopy. Our key finding is that at sufficiently high magnetic fields, the different electronic subsystems merge into one, and the current in a quantum Hall plateau is distributed across the entire width of the Hall bar device
First-principles determination of spin–orbit coupling parameters in two-dimensional materials
No full textSpin–orbit coupling (SOC) is fundamental to many phenomena in solid-state physics. Two-dimensional materials and van der Waals heterostructures provide researchers with exquisite control over this interaction; the ability to fine-tune SOC has impacts on spin transport and relaxation, topological states, optoelectronics, magnetization dynamics and even superconductivity and other correlated states. This Technical Review covers both the theoretical methodology and experimentally relevant phenomenology of SOC in 2D materials, by providing essential insights into the process of extracting the spin interactions from the underlying electronic structure obtained from first-principles density functional theory calculations. This Technical Review begins with graphene. Its SOC has a surprisingly complicated origin yet graphene remains the benchmark for other elemental centrosymmetric 2D materials in which SOC leads to a mixing of spin-up and spin-down components of the Bloch states. We then discuss spin–orbit materials, such as transition-metal dichalcogenides, in which strong SOC and the lack of space-inversion symmetry yield large spin splittings of the valence and conduction bands. This enables highly efficient optical spin orientation or robust valley Hall effect in transition-metal dichalcogenides. Next, we give guidelines for extracting the spin–orbit characteristics of van der Waals heterostructures, such as graphene/WSe2, which serve as a platform for SOC engineering. For these representative systems, we highlight the essentials of first-principles-based methodology, including supercell formation, strain artefacts, twisting, gating and lattice relaxation. Finally, we briefly discuss the effects of proximity exchange coupling, which is another relevant spin interaction for spintronics
Fallbeispiel Lucy – Fallbeispiel einer Jugendlichen mit Lernschwierigkeiten Version 0.1
Get PDFDas Fallbeispiel Lucy wurde von Expertinnen in der sonderpädagogischen und inklusiven Praxis entwickelt. Das realitätsnähe, aber fiktive Fallbeispiel kann in der Lehrkräftebildung eingesetzt werden. Es ist in deutscher und englischer Sprache als veränderbares Werk mit Open Access veröffentlicht.
Zusätzlich kann das Einzelfallraster für pädagogische Diagnostik (Lutz, 2023) als Strukturierungshilfe verwenden werden, um übersichtlich protektive und Risikofaktoren in Bezug auf das Fallbeispiel und dessen Umfeld darzustellen
Hypnosis as a non-pharmacological intervention for invasive medical procedures - A systematic review and meta-analytic update
Get PDFHypnosis is recognized as an effective non-pharmacological intervention for managing anxiety, pain, and physiological stress during invasive medical procedures. Despite its growing use, variability in techniques and inconsistent outcome measurements have challenged its clinical standardization. This systematic review and meta-analysis evaluated the effectiveness of hypnosis in reducing anxiety, pain, and physiological stress during invasive procedures, while identifying the most effective techniques as well as assessing analgesic use and safety. A comprehensive literature search was conducted in PubMed, Cochrane Library, and Scopus to identify randomized controlled trials (RCTs) evaluating hypnosis in invasive procedures. Eligible studies were assessed for bias using the Revised Cochrane Risk of Bias Tool. Meta-analyses were performed with a random-effects model, and subgroup analyses were conducted based on hypnosis techniques, patient characteristics, and procedure types. Twenty RCTs with 1250 patients were included. Hypnosis significantly reduced anxiety (SMD = −0.43, 95 % CI: −0.58 to −0.28, p < 0.001) and pain (SMD = −0.35, 95 % CI: −0.50 to −0.20, p < 0.001) compared to standard care. Subgroup analyses indicated that virtual reality-enhanced hypnosis and tailored interventions for high-anxiety procedures were most beneficial. Physiological stress markers, including heart rate and blood pressure, were also reduced, supporting the calming effects of hypnosis. Adverse effects were minimal. Hypnosis is effective and safe for reducing anxiety and pain during invasive medical procedures. Standardized protocols and further research are needed to optimize its clinical use and enhance adoption in routine care
Preassembly-Controlled Radical Recombination at Bismuth: Decarboxylative C–N Coupling with Sulfonamides
Get PDFPersistent transition metal radicals form the foundation for many metallaphotoredox protocols. Their ability to efficiently trap organic radicals and convert them into various coupling products has inspired the exploration of selective radical reactions even beyond the d-block. Radical processes involving bismuth hold great potential but innovative strategies are required to control the reactivity of bismuth intermediates. Herein we report preassembly as a powerful strategy to enforce a selective recombination of a bismuth(II) radical and an organic radical. As a result, an inner-sphere pathway is accessed, enabling the formation of C–N coupling products
