On the indistinguishability of Raman photons

We provide a theoretical framework to study the effect of dephasing on the quantum indistinguishability of single photons emitted from a coherently driven cavity QED $\Lambda$-system. We show that with a large excited-state detuning, the photon indistinguishability can be drastically improved provided that the fluctuation rate of the noise source affecting the excited state is fast compared with the photon emission rate. In some cases a spectral filter is required to realize this improvement, but the cost in efficiency can be made small.Comment: 18 pages, 3 figures, final versio

Lipid-Based Nanovectors for Targeting of CD44-Overexpressing Tumor Cells

Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan that exists in living systems, and it is a major component of the extracellular matrix. The hyaluronic acid receptor CD44 is found at low levels on the surface of epithelial, haematopoietic, and neuronal cells and is overexpressed in many cancer cells particularly in tumour initiating cells. HA has been therefore used as ligand attached to HA-lipid-based nanovectors for the active targeting of small or large active molecules for the treatment of cancer. This paper describes the different approaches employed for the preparation, characterization, and evaluation of these potent delivery systems

Protection against Clostridium difficile infection in a hamster model by oral vaccination using flagellin FliC-loaded pectin beads

International audienceClostridium difficile flagellin FliC is a highly immunogenic pathogen-associated molecular pattern playing a key role in C. difficile pathogenesis and gut colonization. Here, we designed an oral vaccine against C. difficile with FliC encapsulated into pectin beads for colonic release. Bead stability and FliC retention was confirmed in vitro using simulated intestinal media (SIM), while bead degradation and FliC release was observed upon incubation in simulated colonic media (SCM). The importance of FliC encapsulation into pectin beads for protection against C. difficile was assessed in a vaccination assay using a lethal ham-ster model of C. difficile infection. Three groups of hamsters orally received either FliC-loaded beads or unloaded beads in gastro-resistant capsule to limit gastric degradation or free FliC. Two other groups were immunized with free FliC, one intra-rectally and the other intra-peritoneally. Hamsters were then challenged with a lethal dose of C. difficile VPI 10463. Fifty percent of hamsters orally immunized with FliC-loaded beads survived whereas all hamsters orally immunized with free FliC died within 7 days post challenge. No significant protection was observed in the other groups. Only intra-peritoneally immunized hamsters presented anti-FliC IgG antibodies in sera after immunizations. These results suggest that an oral immunization with FliC-loaded beads probably induced a mucosal immune response, therefore providing a protective effect. This study confirms the importance of FliC encapsulation into pectin beads for a protective oral vaccine against C. difficile

Immunotoxicity of poly (lactic-co-glycolic acid) nanoparticles: influence of surface properties on dendritic cell activation

International audienc

PENGEMBANGAN PROGRAM INTERVENSI DINI BERSUMBERDAYA KELUARGA PADA ANAK CEREBRAL PALSY DENGAN HAMBATAN KOMUNIKASI

Penelitian ini dilatarbelakangi oleh kurangnya pemahaman, penerimaan, dan sikap orang tua terhadap hambatan yang dihadapi anak. Hal ini berdampak pada kemampuan keluarga dalam memberikan layanan intervensi dini di rumah. Tujuan dari penelitian ini adalah untuk merumuskan program intervensi dini bersumber daya keluarga yang akan menjadi pedoman orang tua dalam melaksanakan intervensi. Penelitian ini menggunakan pendekatan kualitatif dengan metode deskriptif. Subjek dalam penelitian ini adalah satu keluarga yang memiliki anak Cerebral Palsy dengan hambatan komunikasi di Ciamis. Teknik pengumpulan data yang digunakan adalah observasi, wawancara, dan studi dokumentasi. Hasil penelitian menunjukkan bahwa: 1) anak memiliki hambatan komunikasi yang pencapaian perkembangan komunikasi verbalnya setara dengan anak usia 2-3 tahun dan usia kalender saat ini 5 tahun. 2) rendahnya tingkat pemahaman orangtua terhadap hambatan anak. 3). Rumusan program intervensi dini bersumber daya keluarga ini berdasarkan kondisi objektif serta kebutuhan keluarga dan anak. 4). tingkat pemahaman orang tua mengenai hambatan anak meningkat serta terjadi perubahan sikap dan perilaku orang tua kepada anak;--- The study was motivated by the lack of understanding, acceptance as well as the attitude of the parents toward their child’s obstacles. It somehow has an impact on family’s capacity to give early intervention support at home. This study was aimed at formulating an early intervention program to the child. The study used descriptive qualitative method involving a single family having a child suffering from Cerebral Palsy causing communication barrier at Ciamis. The techniques used in collecting the data were observations, interviews, and document analysis. The study revealed several findings as follows: 1) the child had communication barrier which made her communication verbal developmental stage was equal to 2-3 years old children. 2) The lack of understanding, acceptance and attitude of the parents toward their child’s communication barrier as well as the support in delivering early intervention at home. 3) The early intervention family-based program’s formulation was based on the objective condition as well as the needs’ of both the child and the parents. 4) The level understanding parents of the barriers to child increase and a change in attitudes and behavior of parents to child

Coherent Population Trapping of Single Spins in Diamond Under Optical Excitation

Coherent population trapping is demonstrated in single nitrogen-vacancy centers in diamond under optical excitation. For sufficient excitation power, the fluorescence intensity drops almost to the background level when the laser modulation frequency matches the 2.88 GHz splitting of the ground states. The results are well described theoretically by a four-level model, allowing the relative transition strengths to be determined for individual centers. The results show that all-optical control of single spins is possible in diamond.Comment: minor correction

Photoluminescence of single colour defects in 50 nm diamond nanocrystals

We used optical confocal microscopy to study optical properties of diamond 50 nm nanocrystals first irradiated with an electron beam, then dispersed as a colloidal solution and finally deposited on a silica slide. At room temperature, under CW laser excitation at a wavelength of 514.5 nm we observed perfectly photostable single Nitrogen-Vacancy (NV) colour defects embedded in the nanocrystals. From the zero-phonon line around 575 nm in the spectrum of emitted light, we infer a neutral NV0 type of defect. Such nanoparticle with intrinsic fluorescence are highly promising for applications in biology where long-term emitting fluorescent bio-compatible nanoprobes are still missing.Comment: proceedings of ICDS 23 conference (23rd International Conference on Defects in Semiconductors, July 24 - July 29, 2005, Awaji Island, Hyogo, Japan); to appear in "Physica B

Learned Pre-Processing for Automatic Diabetic Retinopathy Detection on Eye Fundus Images

Diabetic Retinopathy is the leading cause of blindness in the working-age population of the world. The main aim of this paper is to improve the accuracy of Diabetic Retinopathy detection by implementing a shadow removal and color correction step as a preprocessing stage from eye fundus images. For this, we rely on recent findings indicating that application of image dehazing on the inverted intensity domain amounts to illumination compensation. Inspired by this work, we propose a Shadow Removal Layer that allows us to learn the pre-processing function for a particular task. We show that learning the pre-processing function improves the performance of the network on the Diabetic Retinopathy detection task.Comment: Accepted to International Conference on Image Analysis and Recognition ICIAR 2019 Published at https://doi.org/10.1007/978-3-030-27272-2_3

Coupling Single NV Centers in Diamond to Optical Microcavities

Coupling of the NV^- ZPL to a silica microcavity and tapered fiber is demonstrated at cryogenic temperatures. Coupling to a high-Q cavity should enhance the usefulness of the NV^-for quantum information applications