Sampling rate in the dynamic speckle analysis

Dynamic laser speckle and its biological version (biospeckle laser) have been used in many areas of knowledge. Its noninvasive approach allows the application in advantage regarding those that need contact or damage the analyzed sample. However, one needs the sharp adjust of the image acquiring and processing. In this article, we show how the variation of sampling rate in a dynamic speckle analysis affects the value of dynamic speckle indexes concerning the absolute value of the differences index, the temporal speckle standard deviation index, and the temporal speckle mean index. We show that the dynamic speckle index value changes its maximum excursion with the variation of sampling rate, affected directly by the camera's time integration (time of exposure). We highlight the importance of knowing the frequency band of the analyzed phenomenon and its signal to choose the appropriate sampling rate, with the recommendation of using the lowest sampling rate possible¿without compromise the speckle grains¿to obtain an acceptable maximum excursion and an illumination level with a good signal-noise ratio. The results will help those who work with the phenomenon/technique to enhance their analysis tailoring the set up and yielding reliable results, since the optical method demands a rigorous bias of the image acquiring and processing

Performance of Nelore Cattle on \u3cem\u3ePanicum maximum\u3c/em\u3e Pastures in the Brazilian Cerrado

With the increased demand for meat products, associated with environmental concerns due to global climatic and land use changes, the need to efficiently use pasture and forage resources will increase (Boval and Dixon 2012). Efforts to breed and release new forage cultivars must incorporate these concerns, ensuring that introduced material is of high quality, especially under grazing (Euclides et al. 2008). In this study, we aimed to evaluate the average daily weight gain and stocking rate of Nelore beef cattle grazing new genotypes of Panicum maximum during the rainy season in the Brazilian Cerrado

XIPE: the X-ray Imaging Polarimetry Explorer

X-ray polarimetry, sometimes alone, and sometimes coupled to spectral and temporal variability measurements and to imaging, allows a wealth of physical phenomena in astrophysics to be studied. X-ray polarimetry investigates the acceleration process, for example, including those typical of magnetic reconnection in solar flares, but also emission in the strong magnetic fields of neutron stars and white dwarfs. It detects scattering in asymmetric structures such as accretion disks and columns, and in the so-called molecular torus and ionization cones. In addition, it allows fundamental physics in regimes of gravity and of magnetic field intensity not accessible to experiments on the Earth to be probed. Finally, models that describe fundamental interactions (e.g. quantum gravity and the extension of the Standard Model) can be tested. We describe in this paper the X-ray Imaging Polarimetry Explorer (XIPE), proposed in June 2012 to the first ESA call for a small mission with a launch in 2017 but not selected. XIPE is composed of two out of the three existing JET-X telescopes with two Gas Pixel Detectors (GPD) filled with a He-DME mixture at their focus and two additional GPDs filled with pressurized Ar-DME facing the sun. The Minimum Detectable Polarization is 14 % at 1 mCrab in 10E5 s (2-10 keV) and 0.6 % for an X10 class flare. The Half Energy Width, measured at PANTER X-ray test facility (MPE, Germany) with JET-X optics is 24 arcsec. XIPE takes advantage of a low-earth equatorial orbit with Malindi as down-link station and of a Mission Operation Center (MOC) at INPE (Brazil).Comment: 49 pages, 14 figures, 6 tables. Paper published in Experimental Astronomy http://link.springer.com/journal/1068

Evaluation of fluorescence in situ hybridisation (FISH) for the detection of fungi directly from blood cultures and cerebrospinal fluid from patients with suspected invasive mycoses

The aim of this study was to evaluate the diagnostic performance of in-house FISH (fluorescence in situ hybridisation) procedures for the direct identification of invasive fungal infections in blood cultures and cerebrospinal fluid (CSF) samples and to compare these FISH results with those obtained using traditional microbiological techniques and PCR targeting of the ITS1 region of the rRNA gene. In total, 112 CSF samples and 30 positive blood cultures were investigated by microscopic examination, culture, PCR-RFLP and FISH. The sensitivity of FISH for fungal infections in CSF proved to be slightly better than that of conventional microscopy (India ink) under the experimental conditions, detecting 48 (instead of 46) infections in 112 samples. The discriminatory powers of traditional microbiology, PCR-RFLP and FISH for fungal bloodstream infections were equivalent, with the detection of 14 fungal infections in 30 samples. However, the mean times to diagnosis after the detection of microbial growth by automated blood culture systems were 5 hours, 20 hours and 6 days for FISH, PCR-RFLP and traditional microbiology, respectively. The results demonstrate that FISH is a valuable tool for the identification of invasive mycoses that can be implemented in the diagnostic routine of hospital laboratories. © 2015 Da Silva et al