Effect of charging on CdSe/CdS dot-in-rods single-photon emission

The photon statistics of CdSe/CdS dot-in-rods nanocrystals is studied with a method involving post-selection of the photon detection events based on the photoluminescence count rate. We show that flickering between two states needs to be taken into account to interpret the single-photon emission properties. With post-selection we are able to identify two emitting states: the exciton and the charged exciton (trion), characterized by different lifetimes and different second order correlation functions. Measurements of the second order autocorrelation function at zero delay with post- selection shows a degradation of the single photon emission for CdSe/CdS dot-in-rods in a charged state that we explain by deriving the neutral and charged biexciton quantum yields.Comment: 10 pages, 5 figure

Holographic Manipulation of Nanostructured Fiber Optics Enables Spatially-Resolved, Reconfigurable Optical Control of Plasmonic Local Field Enhancement and SERS

Integration of plasmonic structures on step-index optical fibers is attracting interest for both applications and fundamental studies. However, the possibility to dynamically control the coupling between the guided light fields and the plasmonic resonances is hindered by the turbidity of light propagation in multimode fibers (MMFs). This pivotal point strongly limits the range of studies that can benefit from nanostructured fiber optics. Fortunately, harnessing the interaction between plasmonic modes on the fiber tip and the full set of guided modes can bring this technology to a next generation progress. Here, the intrinsic wealth of information of guided modes is exploited to spatiotemporally control the plasmonic resonances of the coupled system. This concept is shown by employing dynamic phase modulation to structure both the response of plasmonic MMFs on the plasmonic facet and their response in the corresponding Fourier plane, achieving spatial selective field enhancement and direct control of the probe's work point in the dispersion diagram. Such a conceptual leap would transform the biomedical applications of holographic endoscopic imaging by integrating new sensing and manipulation capabilities.L.C. and Fi.P. contributed equally to this work. M.D.V. and Fe.P. jointly supervised and are co-last authors of this work. L.C., D.Z., L.M.P., C.C., M.D.V., and Fe.P. acknowledge European Union’s Horizon 2020 Research and Innovation Program under Grant Agreement No. 828972. Fi.P., A.B., and Fe.P. acknowledge European Research Council under the European Union’s Horizon 2020 Research and Innovation Program under Grant Agreement No. 677683. Fi.P., M.D.V., and Fe.P. acknowledge European Union’s Horizon 2020 Research and Innovation Program under Grant Agreement No 101016787. M.P. and M.D.V. acknowledge European Research Council under the European Union’s Horizon 2020 Research and Innovation Program under Grant Agreement No. 692943. M.P., Fe.P., and M.D.V. acknowledge U.S. National Institutes of Health (Grant No. 1UF1NS108177-01). M.D.V. acknowledges U.S. National Institutes of Health (Grant No. U01NS094190)

The SHOX gene and the short stature. Roundtable on diagnosis and treatment of short stature due to SHOX haploinsufficiency: How genetics, radiology and anthropometry can help the pediatrician in the diagnostic process padova (April 20th, 2011)

The growth of the human body depends from a complex interaction between nutritional, environmental and hormonal factors and by a large number of different genes. One of these genes, short stature homeobox (SHOX), is believed to play a major role in growth. SHOX haploinsufficiency is associated with a wide spectrum of conditions, all characterized growth failure such as Leri-Weill dyschondrosteosis , Turner syndrome, short stature with subtle auxological and radiological findings and the so called “idiopathic short stature” (short stature with no specific findings other than growth failure). The document was prepared by a multidisciplinary team (paediatric endocrinologists, paediatrician, radiologist, geneticist and epidemiologist) to focus on the investigation of children with suspected SHOX- deficiency (SHOX-D) for an early identification and a correct diagnostic work - up of this genetic disorder. On the basis of a number of screening studies, SHOX-D appears to be a relatively frequent cause of short stature. The following recommendations were suggested by our multidisciplinary team: (i) a careful family history, measurements of body proportions and detection of any dysmorphic features are important for the suspect of a genetic disorder ,(ii)the presence of any combination of the following physical findings, such as reduced arm span/ height ratio, increased sitting height/height ratio, above average BMI, Madelung deformity, cubitus valgus, short or bowed forearm, dislocation of the ulna at the elbow, or the appearance of muscular hypertrophy, should prompt the clinician to obtain a molecular analysis of the SHOX region, (iii) it is of practical importance to recognise early or mild signs of Madelung deformity on hand and wrist radiographs, (iv) growth hormone ,after stimulation test, is usually normal . However, treatment with rhGH may improve final adult height; the efficacy of treatment is similar to that observed in those treated for Turner syndrome

The Three-Dimensional Signal Collection Field for Fiber Photometry in Brain Tissue

Fiber photometry is used to monitor signals from fluorescent indicators in genetically-defined neural populations in behaving animals. Recently, fiber photometry has rapidly expanded and it now provides researchers with increasingly powerful means to record neural dynamics and neuromodulatory action. However, it is not clear how to select the optimal fiber optic given the constraints and goals of a particular experiment. Here, using combined confocal/2-photon microscope, we quantitatively characterize the fluorescence collection properties of various optical fibers in brain tissue. We show that the fiber size plays a major role in defining the volume of the optically sampled brain region, whereas numerical aperture impacts the total amount of collected signal and, marginally, the shape and size of the collection volume. We show that ~80% of the effective signal arises from 105 to 106 μm3 volume extending ~200 μm from the fiber facet for 200 μm core optical fibers. Together with analytical and ray tracing collection maps, our results reveal the light collection properties of different optical fibers in brain tissue, allowing for an accurate selection of the fibers for photometry and helping for a more precise interpretation of measurements in terms of sampled volume

The SHOX Gene and The Short Stature. Roundtable On Diagnosis and Treatment of Short Stature Due To SHOX Haploinsufficiency: How Genetics, Radiology And Anthropometry Can Help The Pediatrician in The Diagnostic Process Padova

SHOX haploinsufficiency is associated with a wide spectrum of conditions, all characterized growth failure. The document was prepared by a multidisciplinary team (paediatric endocrinologists, paediatrician, radiologist, geneticist and epidemiologist) to focus on the investigation of children with suspected SHOX- deficiency (SHOX-D) for an early identification and a correct diagnostic work - up of this genetic disorder

Updated Italian recommendations for the diagnosis, treatment and follow-up of the first febrile urinary tract infection in young children

Aim: Our aim was to update the recommendations for the diagnosis, treatment and follow-up of the first febrile urinary tract infection in young children, which were endorsed in 2012 by the Italian Society of Pediatric Nephrology. Methods: The Italian recommendations were revised on the basis of a review of the literature published from 2012 to October 2018. We also carried out an ad hoc evaluation of the risk factors to identify children with high-grade vesicoureteral reflux or renal scarring, which were published in the previous recommendations. When evidence was not available, the working group held extensive discussions, during various meetings and through email exchanges. Results: Four major modifications have been introduced. The method for collecting urine for culture and its interpretation has been re-evaluated. We have reformulated the algorithm that guides clinical decisions to proceed with voiding cystourethrography. The suggested antibiotics have been revised, and we have recommended further restrictions of the use of antibiotic prophylaxis. Conclusion: These updated recommendations have now been endorsed by the Italian Society of Pediatric Nephrology and the Italian Society for Pediatric Infectivology. They can also be used to compare other recommendations that are available, as a worldwide consensus in this area is still lacking