Successful sulfonylurea treatment of a neonate with neonatal diabetes mellitus due to a new KCNJ11 mutation.
ABSTRACT Mutations in the KCNJ11 gene, which encodes the Kir6.2 subunit of the ATP-sensitive potassium channel, often result in neonatal diabetes. We describe a female neonate who is a heterozygous for a new missense mutation, V252L, in the KCNJ11 gene and who has been successfully transitioned from insulin to sulfonylurea therapy.
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ABSTRACT: We model the effects of the leaves of mature broadleaf (deciduous) trees on air-to-ground free-space optical communication systems operating through the leaf canopy. The concept of leaf area index (LAI) is reviewed and related to a probabilistic model of foliage consisting of obscuring leaves randomly distributed throughout a treetop layer. Individual leaves are opaque. The expected fractional unobscured area statistic is derived as well as the variance around the expected value. Monte Carlo simulation results confirm the predictions of this probabilistic model. To verify the predictions of the statistical model experimentally, a passive optical technique has been used to make measurements of observed sky illumination in a mature broadleaf environment. The results of the measurements, as a function of zenith angle, provide strong evidence for the applicability of the model, and a single parameter fit to the data reinforces a natural connection to LAI. Specific simulations of signal-to-noise ratio degradation as a function of zenith angle in a specific ground-to-unmanned aerial vehicle communication situation have demonstrated the effect of obscuration on performance.Applied Optics 02/2006; 45(1):191-200. · 1.69 Impact Factor
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ABSTRACT: We investigate robust optical wireless communication in a highly scattering propagation medium using multielement optical detector arrays. The communication setup consists of synchronized multiple transmitters that send information to a receiver array and an atmospheric propagation channel. The mathematical model that best describes this scenario is multi-input to multi-output communication through stochastic slow changing channels. In this model, signals from m transmitters are received by n receiver-detectors. The channel transfer function matrix is G, and its size is n x m. G(i,j) is the transfer function from transmitter i to detector j, and m > or = n. We adopt a quasi-stationary approach in which the channel time variation has a negligible effect on communication performance over a burst. The G matrix is calculated on the basis of the optical transfer function of the atmospheric channel (composed of aerosol and turbulence elements) and the receiver's optics. In this work we derive a performance model using environmental data, such as documented turbulence and aerosol models and noise statistics. We also present the results of simulations conducted for the proposed detection algorithm.Journal of the Optical Society of America A 07/2006; 23(7):1722-30. · 1.67 Impact Factor
Conference Proceeding: Performance of an optical wireless communication system as a function of wavelength[show abstract] [hide abstract]
ABSTRACT: Free-space optical communication has attracted considerable attention recently for a variety of applications. Special attention has been paid to how adverse weather conditions and background radiation affect transmission through the atmosphere. Due to these effects, the performance of laser communication (lasercom) systems is extremely dependent on the laser transmission wavelength. Available weather statistic measurements indicate that weather effects can be mitigated by using medium and far-IR laser sources. In that case, the new and versatile quantum cascade lasers (QCLs), which are adjusted to operate within the atmospheric window regions in the mid-wave and long-wave IR (MWIR and LWIR) 3-20 μm wavelength band, can provide a viable solution to this problem. In this work, we analyze the wavelength dependence of lasercom system performance under different weather conditions for the purpose of making recommendations on preferable transmission wavelengths within the 0.4-20 μm band.Electrical and Electronics Engineers in Israel, 2002. The 22nd Convention of; 01/2003