Various Compressed Sensing Set-Ups Evaluated Against Shannon Sampling Under Constraint of Constant Illumination

Under the constraint of constant illumination, an information criterion is formulated for the Fisher information that compressed sensing measurements in optical and transmission electron microscopy contain about the underlying parameters. Since this approach requires prior knowledge of the signal's support in the sparse basis, we develop a heuristic quantity, the detective quantum efficiency (DQE), that tracks this information criterion well without this knowledge. It is shown that for the investigated choice of sensing matrices, and in the absence of read-out noise, i.e. with only Poisson noise present, compressed sensing does not raise the amount of Fisher information in the recordings above that of Shannon sampling. Furthermore, enabled by the DQE's analytical tractability, the experimental designs are optimized by finding out the optimal fraction of on-pixels as a function of dose and read-out noise. Finally, we introduce a regularization and demonstrate, through simulations and experiment, that it yields reconstructions attaining minimum mean squared error at experimental settings predicted by the DQE as optimal.Comment: 18 pages, 13 figures. New Monte Carlo simulations in Figure 13 showing the behavior of the single-pixel camera under various magnitudes of read-out nois

Development of Low-Cost Inverted Microscope to Detect Early Growth of Mycobacterium tuberculosis in MODS Culture

The microscopic observation drug susceptibility (MODS) assay for rapid, low-cost detection of tuberculosis and multidrug resistant tuberculosis depends upon visualization of the characteristic cording colonies of Mycobacterium tuberculosis in liquid media. This has conventionally required an inverted light microscope in order to inspect the MODS culture plates from below. Few tuberculosis laboratories have this item and the capital cost of $5,000 for a high-end microscope could be a significant obstacle to MODS roll-out.We hypothesized that the precise definition provided by costly high-specification inverted light microscopes might not be necessary for pattern recognition.In this work we describe the development of a low-cost artesenal inverted microscope that can operate in both a standard or digital mode to effectively replace the expensive commercial inverted light microscope, and an integrated system that could permit a local and remote diagnosis of tuberculosis

Diseño y construcción de un equipo para la medición del scattering de luz producido por partículas dielécticas micrométricas en suspensión coloidal

Se diseñó y construyó un equipo para la medición del Scattering de luz angular de partículas dieléctricas micrométricas en suspensión coloidal. Como fuente de luz se utilizó un láser He-Ne de 632,8 nm y un láser de estado sólido de 532,0 nm y se estudió el efecto de la longitud de onda en la distribución angular de Scattering. Se utilizaron partículas comerciales monodispersas de poliestireno de 0,49 y 1,03 µm de diámetro nominal para obtener curvas de Scattering experimentales, estas fueron comparadas con curvas de Scattering teóricas para estimar el tamaño de partícula. Los resultados obtenidos muestran buena repetitividad y confiabilidad del equipo para la estimación de tamaño de partícula. Se utilizó un microscopio electrónico de transmisión para medir el tamaño de las partículas comerciales utilizadas.Tesi

DNA fingerprinting of closely related cultivars of sweet cherry

Simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers were evaluated in an effort to reliably DNA fingerprint sweet cherry (Prunus avium L.) cultivars and advanced selections from the breeding program at the Summerland Research and Development Center (Summerland, BC, Canada). SSR markers were found that differentiated the 35 cultivars and selections tested. However, groups of cultivars closely related to the parental cultivars, Lapins and Sweetheart, were differentiated by only a few SSR markers each. These last few markers were discovered by specifically screening within these small groups of cultivars and the resulting markers had lower discriminating power (Dj) statistics within the full set of 35 cultivars and selections. To further characterize the differences in one of these closely related groups, SNP markers were identified in the cultivar Sweetheart and an analysis was made of how these markers segregated into three of its open-pollinated progeny. Large blocks of the ‘Sweetheart’ genome (34%) did not contain informative SNP markers, which was consistent with its ancestry where the cultivar Van is both a parent and grandparent. The three progeny cultivars differed from ‘Sweetheart’ at 14%, 31%, and 29% of the 3011 SNP positions tested. These were located in blocks of linked haplotypes covering from 2.5 to 20 million bps each and were distinct for the three cultivars. The cultivar Staccato®, which required the most effort for SSR marker discrimination, also had the lowest number of SNP position differences from ‘Sweetheart’ (14%). These informative SNP markers were located in only five small regions of the sweet cherry genome, which also contained the discriminating SSR markers and provides an explanation for the difficulty of locating SSR markers for this cultivar. In addition to clearly differentiating these cultivars, this SNP analysis shows the level of variation expected within this closely related group. © 2018, American Society for Horticultural Science. All rights reserved