In vitro assessment of internal implant abutment connections with different cone angles under static loading using synchrotron based radiation

Background The stability of implant abutment connection is crucial to minimize mechanical and biological complications. Therefore, an assessment of the microgap behavior and abutment displacement in different implant abutment designs was performed. Methods Four implant systems were tested, three with a conical implant abutment connection based on friction fit and a cone angle amp; 8201; lt; amp; 8201;12 Medentika, Medentis, NobelActive and a system with an angulated connection lt; amp; 8201;40 Semados . In different static loading conditions 30 N amp; 8201; amp; 8722; amp; 8201;90 , 100 N amp; 8201; amp; 8722; amp; 8201;90 , 200 N amp; 8201; amp; 8722; amp; 8201;30 the microgap and abutment displacement was evaluated using synchrotron based microtomography and phase contrast radioscopy with numerical forward simulation of the optical Fresnel propagation yielding an accuracy down to 0.1 amp; 956;m. Results Microgaps were present in all implant systems prior to loading 0.15 9 amp; 956;m . Values increased with mounting force and angle up to 40.5 amp; 956;m at an off axis loading of 100 N in a 90 angle. Conclusions In contrast to the implant abutment connection with a large cone angle 45 , the conical connections based on a friction fit small cone angles with lt; amp; 8201;12 demonstrated an abutment displacement which resulted in a deformation of the outer implant wall. The design of the implant abutment connection seems to be crucial for the force distribution on the implant wall which might influence peri implant bone stabilit

Solution driven processing of calcium sulfate The mechanism of the reversible transformation of gypsum to bassanite in brines

Here, we show that calcium sulfate dihydrate gypsum can be directly, rapidly and reversibly converted to calcium sulfate hemihydrate bassanite in high salinity solutions brines . The optimum conditions for the efficient production of bassanite in a short time lt;5 min involve the use of brines with c NaCl gt; 4 M and maintaining a temperature, T gt; 80 C. When the solution containing bassanite crystals is cooled down to around room temperature, eventually gypsum is formed. When the temperature is raised again to T gt; 80 C, bassanite is rapidly re precipitated. This contrasts with the better known behaviour of the bassanite phase in low salt environments. In low salinity aqueous solutions, bassanite is considered to be metastable with respect to gypsum and anhydrite, and therefore gypsum to bassanite conversion does not occur in pure water. Interestingly, the high salinity transformation of gypsum to bassanite has been reported by many authors and used in practice for several decades, although its very occurrence actually contradicts numerical thermodynamic predictions regarding solubility of calcium sulfate phases. By following the evolution of crystalline phases with in situ and time resolved X ray diffraction scattering and Raman spectroscopy, we demonstrated that the phase stability in brines at elevated temperatures was inaccurately represented in the thermodynamic databases. Most notably for c NaCl gt; 4 M, and T gt; 80 C gypsum becomes readily more soluble than bassanite, which induces the direct precipitation of the latter from gypsum. The fact that these transformations are controlled by the solution provides extensive opportunities for precise manipulation of crystal formation. Our experiments confirmed that bassanite remained the sole crystalline phase for many hours before reverting into gypsum. This property is extremely advantageous for practical processing and efficient crystal extraction in industrial scenario

Interplay of lattice spin orbital coupling and Jahn Teller effect in noncollinear spinel TixMn1 x FeyCo1 y 2O4 a neutron diffraction study

Local magnetostructural changes and dynamical spin fluctuations in doubly diluted spinel TixMn1 amp; 8210;x FeyCo1 amp; 8210;y 2O4 has been reported by means of neutron diffraction and magnetization studies. Two distinct sets of compositions i x Ti 0.20 and y Fe 0.18; ii x Ti 0.40 and y Fe 0.435 have been considered for this study. The first compound of equivalent stoichiometry Ti0.20Mn0.80Fe0.36Co1.64O4 exhibits enhanced tetragonal distortion across the ferrimagnetic transition temperature TC 258 K in comparison to the end compound MnCo2O4 TC amp; 8764; 180 K with a characteristic ratio ct amp; 8730;2at of 0.99795 8 demonstrating robust lattice spin orbital coupling. However, in the second case Ti0.40Mn0.60Fe0.87Co1.13O4 with higher B site compositions, the presence of Jahn Teller ions with distinct behavior appears to counterbalance the strong tetragonal distortion thereby ceasing the lattice spin orbital coupling. Both the investigated systems show the coexistence of noncollinear antiferromagnetic and ferrimagnetic components in cubic and tetragonal settings. On the other hand, the dynamical ac susceptibility, amp; 967;ac T reveals a cluster spin glass state with Gabay Toulouse GT like mixed phases behaviour below TC. Such dispersive behaviour appears to be sensitive to the level of octahedral substitution. Further, the field dependence of amp; 967;ac T follows the weak anisotropic GT line behaviour with crossover exponent amp; 934; lies in the range 1.38 1.52 on the H T plane which is in contrast to the B site Ti substituted MnCo2O4 spinel that appears to follow irreversible non mean field AT line behaviour amp; 934; amp; 8764; 3 amp; 948; . Finally, the Arrott plots analysis indicates the presence of a pseudo first order like transition T lt; 20 K which is in consonance with and zero crossover of the magnetic entropy change within the frozen spin glass regim

Automated quantification of vacuole fusion and lipophagy in Saccharomyces cerevisiae from fluorescence and cryo soft X ray microscopy data using deep learning

During starvation in the yeast Saccharomyces cerevisiae vacuolar vesicles fuse and lipid droplets LDs can become internalized into the vacuole in an autophagic process named lipophagy. There is a lack of tools to quantitatively assess starvation induced vacuole fusion and lipophagy in intact cells with high resolution and throughput. Here, we combine soft X ray tomography SXT with fluorescence microscopy and use a deep learning computational approach to visualize and quantify these processes in yeast. We focus on yeast homologs of mammalian NPC1 NPC intracellular cholesterol transporter 1; Ncr1 in yeast and NPC2 proteins, whose dysfunction leads to Niemann Pick type C NPC disease in humans. We developed a convolutional neural network CNN model which classifies fully fused versus partially fused vacuoles based on fluorescence images of stained cells. This CNN, named Deep Yeast Fusion Network DYFNet , revealed that cells lacking Ncr1 ncr1 amp; 8710; cells or Npc2 npc2 amp; 8710; cells have a reduced capacity for vacuole fusion. Using a second CNN model, we implemented a pipeline named LipoSeg to perform automated instance segmentation of LDs and vacuoles from high resolution reconstructions of X ray tomograms. From that, we obtained 3D renderings of LDs inside and outside of the vacuole in a fully automated manner and additionally measured droplet volume, number, and distribution. We find that ncr1 amp; 8710; and npc2 amp; 8710; cells could ingest LDs into vacuoles normally but showed compromised degradation of LDs and accumulation of lipid vesicles inside vacuoles. Our new method is versatile and allows for analysis of vacuole fusion, droplet size and lipophagy in intact cell

Field induced magnetic transitions in the highly anisotropic ferrimagnet ErFe5Al7 studied by high field x ray magnetic dichroism

We present a comprehensive study of the magnetic properties of the strongly anisotropic ferrimagnet ErFe5Al7 in pulsed magnetic fields up to 30 T applied along the hard magnetization axis within the basal plane of the tetragonal lattice around the compensation temperature Tcomp . Macroscopic measurements showed two anomalies at about 8 T and 25 T in a small temperature range around Tcomp. High field x ray magnetic circular dichroism XMCD data at the Er M5 and the Fe L3 edge resonances provide insight into the element selective magnetization processes, revealing a coherent rotation of Er 4f and Fe 3d moments, with stepwise jumps including an unexpected one from an easy to a hard magnetization axis. XMCD at the Er L3 edge resonance elucidates the role of Er 5d electrons in coupling the Er 4f and the Fe 3d moments. Finally, an in plane anisotropy constant was evaluated from a simulation of the magnetization process at temperatures well below Tcomp using a two sublattice mode

How Atomic Bonding Plays the Hardness Behavior in the Al Co Cr Cu Fe Ni High Entropy Family

A systematic study on a face centered cubic based compositionally complex alloy system Al Co Cr Cu Fe Ni in its single phase state is carried out, where a mother senary compound Al8Co17Cr17Cu8Fe17Ni33 and five of its suballoys, obtained by removing one element at a time, are investigated and exhaustively analyzed determining the contribution of each alloying element in the solid solution. The senary and the quinaries are compared using experimental techniques including X ray absorption spectroscopy, X ray diffraction, transmission electron microscopy, and first principles hybrid Monte Carlo molecular dynamics simulations. Chemical short range order and bond length distances have been determined both at the experimental and computational level. Electronic structure and local atomic distortions up to 5.2 amp; 8201; have been correlated to the microhardness values. A linear regression model connecting hardness with local lattice distortions is presente

Improved Air Stability of Tin Halide Perovskite Solar Cells by an N Type Active Moisture Barrier

Tin halide perovskite solar cells are promising for the next generation of highly efficient photovoltaics. Their commercialization can be accelerated by increasing their stability in moisture and oxygen. Herein, an n type organic molecule IO 4Cl is applied as an interlayer between the perovskite films and electron transport layers in p i n structured devices. The electron rich indacenodithieno [3,2 b]thiophene enhances electron transport, while the hydrocarbon side chains and rigid conjugated backbone isolate air. It is also shown that the C amp; 9552;O in IO 4Cl can coordinate with Sn2 on perovskite films surface and grain boundaries to enhance perovskite crystal stability. In addition, IO 4Cl slows down crystallization dynamics, resulting in lower non radiation recombination. The moisture ingress in the perovskite films is tracked under high relative humidity RH and it is found that IO 4Cl can mitigate moisture infiltration. Finally, the devices with IO 4Cl maintain 95 of the initial power conversion efficiency after 1200 h of storage in a nitrogen filled glovebox, and their stability in ambient air 60 80 RH is significantly improved against pristine devices, thus demonstrating the beneficial effects of IO 4Cl interlayer on device stabilit

Nanocrystal residual strains and density layers enhance failure resistance in the cleithrum bone of evolutionary advanced pike fish

Failure resistant designs are particularly crucial for bones subjected to rapid loading, as is the case for the ambush hunting northern pike Esox lucius . These fish have slim and low density osteocyte lacking bones. As part of the swallowing mechanism, the cleithrum bone opens and closes the jaw. The cleithrum needs sufficient strength and damage tolerance, to withstand years of repetitive rapid gape and suck cycles of feeding. The thin wing shaped bone comprises anisotropic layers of mineralized collagen fibers that exhibit periodic variations in mineral density on the mm and micrometer length scales. Wavy collagen fibrils interconnect these layers yielding a highly anisotropic structure. Hydrated cleithra exhibit Young s moduli spanning 3 9 GPa where the yield stress of amp; 8764;40 MPa increases markedly to exceed amp; 8764;180 MPa upon drying. This 5x observation of increased strength corresponds to a change to brittle fracture patterns. It matches the emergence of compressive residual strains of amp; 8764;0.15 within the mineral crystals due to forces from shrinking collagen layers. Compressive stresses on the nanoscale, combined with the layered anisotropic microstructure on the mm length scale, jointly confer structural stability in the slender and lightweight bones. By employing a range of X ray, electron and optical imaging and mechanical characterization techniques, we reveal the structure and properties that make the cleithra impressively damage resistant composite

Jellyfish A modular code for wave function based electron dynamics simulations and visualizations on traditional and quantum compute architectures

Ultrafast electron dynamics have made rapid progress in the last few years. With Jellyfish, we now introduce a program suite that enables to perform the entire workflow of an electron dynamics simulation. The modular program architecture offers a flexible combination of different propagators, Hamiltonians, basis sets, and more. Jellyfish can be operated by a graphical user interface, which makes it easy to get started for nonspecialist users and gives experienced users a clear overview of the entire functionality. The temporal evolution of a wave function can currently be executed in the time dependent configuration interaction method TDCI formalism, however, a plugin system facilitates the expansion to other methods and tools without requiring in depth knowledge of the program. Currently developed plugins allow to include results from conventional electronic structure calculations as well as the usage and extension of quantum compute algorithms for electron dynamics. We present the capabilities of Jellyfish on three examples to showcase the simulation and analysis of light driven correlated electron dynamics. The implemented visualization of various densities enables an efficient and detailed analysis for the long standing quest of the electron hole pair formatio

Interfacial Passivation Engineering for Highly Efficient Quantum Dot Light Emitting Diodes via Aromatic Amine Functionalized Dipole Molecules

Blue quantum dot QD light emitting diodes QLEDs exhibit unsatisfactory operational stability and electroluminescence EL properties due to severe nonradiative recombination induced by large numbers of dangling bond defects and charge imbalance in QD. Herein, dipolar aromatic amine functionalized molecules with different molecular polarities are employed to regulate charge transport and passivate interfacial defects between QD and the electron transfer layer ETL . The results show that the stronger the molecular polarity, especially with the amp; 8722;CF3 groups possessing a strong electron withdrawing capacity, the more effective the defect passivation of S and Zn dangling bonds at the QD surface. Moreover, the dipole interlayer can effectively reduce electron injection into QD at high current density, enhancing charge balance and mitigating Joule heat. Finally, blue QLEDs exhibit a peak external quantum efficiency EQE of 21.02 with an operational lifetime T50 at 100 cd m 2 exceeding 4000