Abstract Due to the increasing life expectancy, orthopaedic surgeons are more and more often confronted with fragility fractures of the pelvis (FFPs). These kinds of fractures are the result of a ...low-energy impact or they may even occur spontaneously in patients with severe osteoporosis. Due to some distinct differences, the established classifications for pelvic ring lesions in younger adults do not fully reflect the clinical and morphological criteria of FFPs. Most FFPs are minimally displaced and do not require surgical therapy. However, in some patients, an insidious progress of bone damage leads to increasing displacement, nonunion and persisting instability. Therefore, new concepts for surgical treatment have to be developed to address the functional needs of the elderly patients. Based on an analysis of 245 consecutive patients with FFPs, we propose a novel classification system for this condition. This classification is based on morphological criteria and it corresponds with the degree of instability. Also in the elderly, these criteria are the most important for the decision on the type of treatment as well as type and extent of surgery. The estimation of the degree of instability is based on radiological and clinical findings. The classification gives also hints for treatment strategies, which may vary between minimally invasive techniques and complex surgical reconstructions.
Over the years, organic optoelectronics have evolved into a mature technology with a wide range of applications. Their building blocks, namely organic semiconductors, are distinctly different from ...their inorganic counterparts due to orientational degrees of freedom that offer unique possibilities for tailoring their properties in thin‐film structures. In this article, the many facets that molecular orientation has for fundamental aspects, like film growth as well as optical and electrical behavior, are reviewed and the implications of molecular orientation for device application are discussed.
In this article, the many facets of molecular orientation in organic optoelectronics are reviewed. Their building blocks are distinctly different from their inorganic counterparts due to orientational degrees of freedom that offer unique possibilities for tailoring their properties in thin‐film structures. The authors elucidate different orientational properties, tailored measurements, and discuss the implications for device application.
Reactions between BIII species and the novel nucleophilic cyclopentadienyl‐stabilized AlI reagent (1) result in a diversity of complexes bearing different Al/B oxidation states and coordination ...geometries. With the triarylborane B(C6F5)3, a simple AlI→BIII adduct is formed. In contrast, a bulky aryldihaloborane undergoes oxidative addition with the formation of a covalent bora‐alane species. With an N‐heterocyclic carbene‐stabilized amino(bromo)borenium ion, a redox reaction was observed, where the product is a borylene‐alane BI→AlIII complex. Additionally, reaction of 1 with BI3 results in complete scrambling of all of the Al/B‐bound substituents, and the formation of a cyclopentadienylboron(I)→AlI3 complex. These latter reactions are the first examples of the reduction of a boron(III) compound to a borylene by a p‐block reagent, and illustrate how subtle changes in the nature of the borane can result in highly divergent reaction outcomes.
All good things come in threes: Reactions of an AlI nucleophile with BIII species leads to three distinct modes of reactivity: adduct formation (AlI‐BIII), oxidative addition (AlII‐BII), and reduction (AlIII‐BI). IMes=1,3‐dimesitylimidazol‐2‐ylidene, TerPhiPr=bis‐2,6‐(2,4,6‐triisopropylphenyl)phenyl.
It is demonstrated that dipolar doping of hole transport layers (HTLs) controls the density and polarity of the accumulated charge at the critical interface between the HTL and the emission layer ...(EML) in organic light‐emitting diodes (OLEDs). Dipolar doping enables spontaneous orientation polarization (SOP) even in nonpolar HTL, and consequently compensates for the negative interface charge originating from the SOP of the adjacent layer. This concept is applied to a phosphorescent OLED, where bis‐4(N‐carbazolyl)phenylphosphine oxide (BCPO) is employed as a polar dopant for the HTL. The net interface charge is completely compensated at ≈29.5% of doping and further doping even facilitates the positive interface charge. The luminescence loss due to triplet‐polaron quenching is observed for both hole and electron accumulations, and it is suppressed by reducing the net interface charge density. On the other hand, the carrier balance factor linearly decreases with increasing doping ratio of BCPO. The results suggest that besides the energy level offset, SOP and permanent dipole moment of the materials should also be taken into account for realizing efficient carrier blocking interfaces. Dipolar doping is a versatile tool to tune charge accumulation, and to study its influence on device performance as well as the role of SOP in OLEDs.
A method to control the density and polarity of the accumulated charge at the critical interface in organic light‐emitting diodes is demonstrated. The luminescence loss due to triplet‐polaron quenching is suppressed by reducing the net interface charge density. Impacts of spontaneous orientation polarization on the charge blocking ability are also demonstrated.
Defects at transition metal (TM) and rare earth (RE) oxide surfaces, neutral oxygen vacancies in particular, play a major role in a variety of technological applications. This is the motivation of ...numerous studies of partially reduced oxide surfaces. We review, discuss, and compare theoretical data for structural and electronic properties and energetic quantities related to the formation of oxygen defects at TM and RE oxide surfaces using TiO
2, ZrO
2, V
2O
5, and CeO
2 as examples. Bulk defects, as far as relevant for comparison with the properties of reduced surfaces, are briefly reviewed. Special attention is given to the fate of the electrons left in the system upon vacancy formation and the ability of state-of-the-art quantum-mechanical methods to provide reliable energies and an accurate description of the electronic structure of the partially reduced oxide systems.
Mammalian pregnancy involves tremendous de novo maternal vascular construction to adequately support conceptus development. In early mouse decidua basalis (DB), maternal uterine natural killer (uNK) ...cells oversee this process directing various aspects during the formation of supportive vascular networks. The uNK cells recruited to early implantation site DB secrete numerous factors that act in the construction of early decidual vessels (neoangiogenesis) as well as in the alteration of the structural components of newly developing and existing vessels (pruning and remodeling). Although decidual and placental development sufficient to support live births occur in the absence of normally functioning uNK cells, development and structure of implantation site are optimized through the presence of normally activated uNK cells. Human NK cells are also recruited to early decidua. Gestational complications including recurrent spontaneous abortion, fetal growth restriction, preeclampsia, and preterm labor are linked with the absence of human NK cell activation via paternally inherited conceptus transplantation antigens. This review summarizes the roles that mouse uNK cells normally play in decidual neoangiogenesis and spiral artery remodeling in mouse pregnancy and briefly discusses changes in early developmental angiogenesis due to placental growth factor deficiency.
Background Fragility fractures of the pelvis (FFP) represent an increasing clinical entity. Until today, there are no guidelines for treatment of FFP. In our center, recommendation for operative ...treatment was given to all patients, who suffered an FFP type III and IV and to patients with an FFP type IIwith unsuccessful non-operative treatment. We performed a retrospective observational study and investigated differences between fracture classes and management alternatives. We hypothetized that operative treatment may reduce mortality. Materials and methods The medical charts and radiographs of 362 patients were analysed. Patient demographics, FFP-classification, length of hospital stay (LoS), type of treatment, general and surgery-related complications, mortality, Short Form-8 physical component score (SF-8 PCS) and mental component score (SF-8 MCS), Parker Mobility Score (PMS) and Numeric Rating Scale (NRS) were documented. Results 238 patients had FFP type II and 124 FFP type III and IV. 52 patients with FFP type II (21.8%) and 86 patients with FFP type III and IV (69.4%) were treated operatively (p<0.001). Overall mortality did not differ between the fracture classes (p = 0.127) but was significantly lower in the operative group (p<0.001). Median LoS was significantly higher in FFP type III and IV (p<0.001) and in operated patients (p<0.001). There were more in-hospital complications in patients with FFP type III and IV (p = 0.001) and in the operative group (p = 0.006). More patients of the non-operative group were mobile (p<0.001) and independent (p<0.001) at discharge. Half of the patients could not return in their living environment.203 of the 235 surviving patients (86%) answered the questionnaires after a mean follow-up time of 38 months. SF-8 PCS, SF-8 MCS and PMS did not differ between the fracture classes and treatment groups. Pain perception was higher in the operated group (p = 0.013). Conclusion In our study, we observed that operative treatment of FFP provides low mortality rates, although LoS and in-hospital complications were higher in the operative group. At discharge, the non-operative group was more mobile and independent. At follow up, quality of life and mobility were comparable between the groups. Further prospective studies are needed to clarify the impact of operative treatment of FFP on mortality and functional outcome.
Many proteins have the potential to aggregate into amyloid fibrils, protein polymers associated with a wide range of human disorders such as Alzheimer's and Parkinson's disease. The thermodynamic ...stability of amyloid fibrils, in contrast to that of folded proteins, is not well understood: the balance between entropic and enthalpic terms, including the chain entropy and the hydrophobic effect, are poorly characterised. Using a combination of theory, in vitro experiments, simulations of a coarse-grained protein model and meta-data analysis, we delineate the enthalpic and entropic contributions that dominate amyloid fibril elongation. Our prediction of a characteristic temperature-dependent enthalpic signature is confirmed by the performed calorimetric experiments and a meta-analysis over published data. From these results we are able to define the necessary conditions to observe cold denaturation of amyloid fibrils. Overall, we show that amyloid fibril elongation is associated with a negative heat capacity, the magnitude of which correlates closely with the hydrophobic surface area that is buried upon fibril formation, highlighting the importance of hydrophobicity for fibril stability.
Homotypic or heterotypic internalization of another, either living or necrotic cell is currently in the center of research interest. The active invasion of a living cell called entosis and ...cannibalism of cells by rapidly proliferating cancers are prominent examples. Additionally, normal healthy tissue cells are capable of non-professional phagocytosis. This project studied the relationship between non-professional phagocytosis, individual proliferation and cell cycle progression. Three mesenchymal and two epithelial normal tissue cell lines were studied for homotypic non-professional phagocytosis. Homotypic dead cells were co-incubated with adherent growing living cell layers. Living cells were synchronized by mitotic shake-off as well as Aphidicolin-treatment and phagocytotic activity was analyzed by immunostaining. Cell cycle phases were evaluated by flow cytometry. Mesenchymal and epithelial normal tissue cells were capable of internalizing dead cells. Epithelial cells had much higher non-professional phagocytotic rates than mesenchymal cells. Cells throughout the entire cell cycle were able to phagocytose. The phagocytotic rate significantly increased with progressing cell cycle phases. Mitotic cells regularly phagocytosed dead cells, this was verified by Nocodazole and Colcemid treatment. Taken together, our findings indicate the ability of human tissue cells to phagocytose necrotic neighboring cells in confluent cell layers. The origin of the cell line influences the rate of cell-in-cell structure formation. The higher cell-in-cell structure rates during cell cycle progression might be influenced by cytoskeletal reorganization during this period or indicate an evolutionary anchorage of the process. Recycling of nutrients during cell growth might also be an explanation.
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