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The dynamics of a quantum system in a dissipative environment presents a rich and still largely unexplored phenomenology that is relevant for the control of quantum devices. The simplest problem can be modeled as a two-level system—such as a spin—in contact with a thermal bath. Here, we present experiments in which we monitor the spin reversal in a TbPc2 single-molecule spin transistor, and we show that the application of microwave pulses can cause the spin to flip between its two lowest-lying states (| ↑ ⟩ and | ↓ ⟩) at a rate that increases with increasing duration and power of the pulses. This process is neither resonant nor coherent with the microwave pulses. Moreover, an asymmetry appears in the | ↓ ⟩ → | ↑ ⟩ and | ↑ ⟩ → | ↓ ⟩ transition probabilities, suggesting that the process occurs out of equilibrium. We explain the experimental results and provide an estimate of the local temperature increase induced by the microwave pulses by means of a model that takes into account the energy exchange between the single Tb3+ electron spin and the local environment. [ABSTRACT FROM AUTHOR]

Several technological issues have to be faced to realize devices working at the single molecule level. One of the main challenges consists of defining methods to fabricate electrodes to make contact with single molecules. Here, we report the realization of novel spintronic devices made of a TbPc2 single molecule embedded between two nanometer-separated graphene electrodes, obtained by feedback-controlled electroburning. We demonstrate that this approach allows the realisation of devices working at low temperature. With these, we were able to characterize the magnetic exchange coupling between the electronic spin of the Tb3+ magnetic core and the current passing through the molecular system in the Coulomb blockade regime, thus showing that the use of graphene is a promising way forward in addressing single molecules. [ABSTRACT FROM AUTHOR]

Objective. Sinus floor elevation with lateral approach is probably the most frequently performed reconstructive procedure to rehabilitate posterior maxilla when a bone deficiency is present. Different graft materials have been proposed and tested, often with high clinical performances and predictable results. Histological analysis is required when evaluating new materials. We investigated human biopsies retrieved after sinus floor elevation procedure by histomorphometric evaluation to test the performance of an equine-derived bone grafting material. Study Design. Seventeen consecutive patients were enrolled and sinus lift surgeries were performed using an equine bone graft. Six months after surgery, at implant placement, bone samples were collected. Histomorphometry analysis was carried out on decalcified samples. Results. All surgeries were uneventful and no additional grafting was required prior to implant insertion. Forty percent of new bone formation was detected, which represented the most abundant tissue retrieved, followed by the residual graft material (33%) and fibrous tissue (27%). A significant reduction in particles size demonstrates a remodeling activity of the graft material. Conclusion. Within the limitations of this study, this equine-derived bone graft proved to be an effective material to induce new bone formation in the sinus floor elevation procedure. [ABSTRACT FROM AUTHOR]

Aims: Promoting bone formation at the tissue interface is an important step to improve implant success. This study investigated whether stimulation of Wnt signaling by GSK3b inhibitor lithium chloride (LiCl) could affect the response of mesenchymal or osteoblastic cells growing on titanium surfaces with different topography and wettability, and improve their differentiation along the osteoblastic lineage. Material and methods: Murine mesenchymal C2C12 cells were plated on Pickled, acid-etched/sandblasted (SLA), and hydrophilic SLA titanium disks (modSLA) and stimulated with increasing doses of LiCl. Cell viability was measured using chemiluminescence-based ATP quantitation and activation of Wnt canonical signaling was measured using a Luciferase-based reporter assay. Gene expression was measured using real time PCR in C2C12 cells, murine osteoblastic MC3T3 cells or murine primary bone marrow cells. Results: LiCl stimulated Wnt activation and expression of Wnt markers in C2C12 cells on modSLA. Addition of 1 mM LiCl increased levels for bone marker Osteocalcin in MC3T3 cells on modSLA surfaces. Similarly, LiCl potently enhanced Osteoprotegetrin levels in MC3T3 cells on modSLA. When primary bone marrow cells were stimulated with LiCl, the expression of Wnttarget genes and osteoblastic differentiation markers was increased on modSLA surfaces. Conclusions: Stimulation of the canonical Wnt pathway promoted osteoblast differentiation on hydrophilic modSLA surfaces. Taken together, these results demonstrate that Wnt activators such as LiCl should be further tested as a possible approach to improve implant osseointegration. [ABSTRACT FROM AUTHOR]