Hydroxyapatite functionalization to trigger adsorption and release of risedronate

Bisphosphonates are widely employed drugs for the treatment of pathologies characterized by excessive bone resorption, and display a great affinity for apatitic supports. In this work we investigate how hydroxyapatite functionalization can influence the processes of adsorption and release of a bisphosphonate, namely risedronate. To this aim, pure hydroxyapatite (HA), hydroxyapatite with a partial substitution of Zn to Ca (ZnHA) and poly-ethylenimine-functionalized hydroxyapatite (HAPEI) were submitted to interaction with risedronate solution. The results indicate that the mechanisms of adsorption and release are greatly influenced by the type of the apatitic support. All the apatitic supports display Langmuir isotherms for risedronate adsorption. However in the case of HAPEI the plateau is not reached even at high equilibrium concentrations in solution. The data suggest that risedronate adsorption on HAPEI mineral-organic support occurs not only through chemisorption on apatitic phase, as on HA and ZnHA, but also through physisorption involved by PEI coating, which modulates also bisphosphonate release. These properties of tailor-made hydroxyapatite supports could be exploited to develop delivery systems for antiresorptive agents directly on osteoporotic sites

Chiral transport of hot carriers in graphene in the quantum Hall regime

Photocurrent (PC) measurements can reveal the relaxation dynamics of photo-excited hot carriers beyond the linear response of conventional transport experiments, a regime important for carrier multiplication. In graphene subject to a magnetic field, PC measurements are able to probe the existence of Landau levels with different edge chiralities which is exclusive to relativistic electron systems. Here, we report the accurate measurement of PC in graphene in the quantum Hall regime. Prominent PC oscillations as a function of gate voltage on samples' edges are observed. These oscillation amplitudes form an envelope which depends on the strength of the magnetic field, as does the PCs' power dependence and their saturation behavior. We explain these experimental observations through a model using optical Bloch equations, incorporating relaxations through acoustic-, optical- phonons and Coulomb interactions. The simulated PC agrees with our experimental results, leading to a unified understanding of the chiral PC in graphene at various magnetic field strengths, and providing hints for the occurrence of a sizable carrier multiplication.Comment: 14 pages, 13 figure

Sources brillantes de photons uniques indiscernables et démonstration d'une porte logique quantique

The goal of this thesis was the development of new bright sources of both single and indistinguishable photons that we used for implementing a quantum logic gate. For this purpose, we studied and controlled the spontaneous emission of single semiconductor quantum dot embed in optical structures. First, we proposed a new type of three dimensional cavity - easy to realize and that we named "confined Tamm plasmon modes" cavities - in order to control the spontaneous emission of a quantum dot and to create a bright source of single photons. Then, we fabricated and characterized sources of single photons with brightnesses up to 0.79 photons collected per laser pulse. To do so, we deterministically coupled a single quantum dot to the confined mode of a micropillar. The indistinguishability of the photons emitted by the source has been studied as a function of the pumping conditions. Using a two-color excitation scheme, we obtained for the first time a bright source of indistinguishable single photons. Finally, to show the potential of these sources, we implemented a quantum Controlled-Not gate operating on two single photons. This gate, which flips a target qubit state as a function of a control qubit state, is at the heart of the quantum computer. The measurement of the truth table allows us to determine the success probability of the gate. Using this quantum logic gate, we generated two photons entangled in polarization. The fidelity to the Bell state reaches 71%.L'objectif de cette thèse a été de développer de nouvelles sources brillantes de photons à la fois uniques et indiscernables et de les utiliser pour réaliser une porte logique quantique. Pour cela, nous avons étudié et contrôlé l'émission spontanée de boîtes quantiques semi-conductrices insérées dans des structures optiques. Dans un premier temps, nous avons développé un nouveau type de cavités tridimensionnelles - simples à réaliser et que nous avons nommées cavités à " modes de Tamm plasmoniques confinés " - afin de contrôler l'émission spontanée d'une boîte quantique et de créer une source brillante de photons uniques. Dans un second temps, nous avons fabriqué et caractérisé des sources de photons uniques ayant des brillances records allant jusqu'à 0.79 photons collectés par impulsion laser. Pour cela, nous avons couplé de manière déterministe une boîte quantique à un mode confiné de micropilier. L'indiscernabilité des photons émis par la source a été étudiée en fonction des conditions d'excitation. Un schéma d'excitation à deux couleurs nous a permis d'obtenir pour la première fois une grande indiscernabilité entre les photons à forte brillance de la source. Enfin, pour montrer le potentiel de ces sources, nous avons construit une porte logique quantique Controlled-NOT opérant sur deux photons uniques. Cette porte qui retourne l'état d'un qubit de cible en fonction de l'état d'un qubit de contrôle est l'élément de base d'un ordinateur quantique. Grâce à la mesure de la table de vérité, nous avons obtenu le taux de succès de la porte. Finalement, en utilisant cette porte, nous avons généré deux photons intriqués en polarisation. La fidélité à l'état de Bell atteint 71%

Simultaneous, Full Characterization of a Single-Photon State

As single-photon sources become more mature and are used more often in quantum information, communications, and measurement applications, their characterization becomes more important. Single-photon-like light is often characterized by its brightness, as well as two quantum properties: the suppression of multiphoton content and the photon indistinguishability. While it is desirable to obtain these quantities from a single measurement, currently two or more measurements are required. Here, we show that using two-photon (n=2) number-resolving detectors, one can completely characterize single-photon-like states in a single measurement, where previously two or more measurements were necessary. We simultaneously determine the brightness, the suppression of multiphoton states, the indistinguishability, and the statistical distribution of Fock states to third order for a quantum light source. We find n≥3 number-resolving detectors provide no additional advantage in the single-photon characterization. The new method extracts more information per experimental trial than a conventional measurement for all input states and is particularly more efficient for statistical mixtures of photon states. Thus, using this n=2, number-resolving detector scheme will provide advantages in a variety of quantum optics measurements and systems

3287993.pdf

Supplemental Materia

Case Report: Immune Checkpoint Blockade Plus Interferon-Γ Add-On Antifungal Therapy in the Treatment of Refractory Covid-Associated Pulmonary Aspergillosis and Cerebral Mucormycosis

Invasive fungal diseases (IFD) still cause substantial morbidity and mortality, and new therapeutic approaches are urgently needed. Recent data suggest a benefit of checkpoint inhibitors (ICI). We report the case of a diabetic patient with refractory IFD following a SARSCoV-2 infection treated by ICI and interferon-gamma associated with antifungal treatment

Integrierte Informationsverarbeitung mit dem OePNV-Datenmodell. Rahmenlastenhefte Anhaenge zum technischen Schlussbericht

SIGLEAvailable from TIB Hannover: F97B2190+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Scalable performance in solid-state single-photon sources

The desiderata for an ideal photon source are high brightness, high single-photon purity, and high indistinguishability. Defining brightness at the first collection lens, these properties have been simultaneously demonstrated with solid-state sources; however, absolute source efficiencies remain close to the 1% level and indistinguishability has only been demonstrated for photons emitted consecutively on the few-nanoseconds scale. Here, we employ deterministic quantum dot-micropillar devices to demonstrate solid-state single-photon sources with scalable performances. In one device, an absolute brightness at the output of a single-mode fiber of 14% and purities of 97.1%–99.0% are demonstrated. When nonresontantly excited, it emits a long stream of photons that exhibit indistinguishability up to 70%—above the classical limit of 50%—even after 33 consecutively emitted photons with a 400 ns separation between them. Resonant excitation in other devices results in near-optimal indistinguishability values: 96% at short timescales, remaining at 88% in timescales as large as 463 ns after 39 emitted photons. The performance attained by our devices brings solid-state sources into a regime suitable for scalable implementations