Compression of fluorescence microscopy images based on the signal-to-noise estimation

Modern microscopic techniques like high-content screening (HCS), high-throughput screening, 4D imaging, and multispectral imaging may involve collection of thousands of images per experiment. Efficient image-compression techniques are indispensable to manage these vast amounts of data. This goal is frequently achieved using lossy compression algorithms such as JPEG and JPEG2000. However, these algorithms are optimized to preserve visual quality but not necessarily the integrity of the scientific data, which are often analyzed in an automated manner. Here, we propose three observer-independent compression algorithms, designed to preserve information contained in the images. These algorithms were constructed using signal-to-noise ratio (SNR) computed from a single image as a quality measure to establish which image components may be discarded. The compression efficiency was measured as a function of image brightness and SNR. The alterations introduced by compression in biological images were estimated using brightness histograms (earth's mover distance (EMD) algorithm) and textures (Haralick parameters). Furthermore, a microscope test pattern was used to assess the effect of compression on the effective resolution of microscope images.     

Adsorption of rhodium by modified mesoporous cellulose/silica sorbents: equilibrium,kinetic, and thermodynamic studies

A cellulose/silica hybrid was fabricated through the simultaneous deposition of silica and cellulose from their blends. The product was treated with ethylenediamine then carbon disulfide to functionalize amine and thio moieties to the hybrid surface to obtain R-N and R-NS, respectively. The new sorbents obtained were characterized by FT-IR, SEM, and BET. The data obtained indicated the functionalization of amine and thio moieties to the hybrid surface and the formation of thermally stable mesoporous particles with surface area of 319 and 63.5 m² for R-N and R-NS, respectively. Batch and column studies were carried out to verify the behavior of the two sorbents towards Rh(III) ions from their chloride solutions. The batch studies showed maximum uptake capacity values of 51 and 60 mg g^?1, where column studies showed 76.5 and 90 mg g^?1 for R-N, R-NS, respectively. The data obtained were interpreted to get the equilibrium, isotherm, kinetics, and thermodynamics adsorption parameters. The adsorption process is favorable and dominated by entropic changes, follow the pseudo-second order kinetics, and fitted well with Langmuir and Dubinin–Radushkevitch adsorption isotherms. The data obtained from batch and column studies indicates the applicability of the obtained cellulose/silica composites in retrieval of Rh(III) ions at higher efficiency.     

Onset sintering-coarsening-coalescence kinetics of calcite powders

An onset sintering-coarsening-coalescence (SCC) event based on a significant decrease of specific surface area relative to the dry pressed samples after isothermal firing in the 450–600 °C range in air was determined by N₂ adsorption–desorption hysteresis isotherm for submicron-sized calcite powders. The apparent activation energy for such a rapid SCC event was estimated as 57.5 ± 1.0 kJ/mol based on the time for 50% reduction of specific surface area without appreciable phase change of calcite. The minimum temperature to activate the SCC process, as of concern to industrial CaCO₃ applications and natural limestone formation, is 317 °C based on the extrapolation of steady specific surface area reduction rates to null.     

Surface treatment of sol-gel bioglass using dielectric barrier discharge plasma to enhance growth of hydroxyapatite

Surface treatment of sol-gel bioglass is required to increase its biomedical applications. In this study, a dielectric barrier discharge (DBD) plasma treatment in atmospheric pressure was performed on the surface of [SiO₂-CaO-P₂O₅-B₂O₃] sol-gel derived glass. The obtained bioglass was treated by plasma using discharge current 12mA with an exposure period for 30 min. The type of discharge can be characterized by measuring the discharge current and applied potential waveform and the power dissipation. Apatite formation on the surface of the DBD-treated and untreated samples after soaking in simulated body fluid (SBF) at 37 °C is characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), inductively coupled plasma (ICP-OES) and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS). We observed a marked increase in the amount of apatite deposited on the surface of the treated plasma samples than those of the untreated ones, indicating that DBD plasma treatment is an efficient method and capable of modifying the surface of glass beside effectively transforming it into highly bioactive materials.     

Composition dependent structure and elasticity of lithium silicate glasses: Effect of ZrO2 additive and the combination of alkali silicate glasses

The elasticity and structure of lithium silicate glasses Li₂O·3SiO₂, Li₂O·2SiO₂, and Li₂O·2SiO₂·0.135ZrO₂ were studied at ambient conditions, using both Raman and Brillouin spectroscopies. The conventional nucleating agent, i.e., Zr⁴⁺ caused a more polymerized silicate network, amorphous phase separation before crystallization, and a significant drop in shear, Young's and bulk moduli, though Raman spectra have revealed that the partial substitution of Zr for Si occurred chiefly in the less polymerized Q² species. The compiled data of alkali silicate glasses M₂O–SiO₂ (M = Li, Na, K) showed that each glass displays different M₂O concentrations for getting minimum bulk modulus due to difference in field strength of cations, depolymerization of silicate network, and coordination number of cations. The specific M₂O concentrations for such minima increase with increasing cation size. Different composition dependences of elastic moduli for the glasses having same constituents can be ascribed to different mechanisms for compression and shear deformation.     

Morphological differentiation of seven parthenogenetic Artemia (Crustacea: Branchiopoda) populations from China,with special emphasis on ploidy degrees

Parthenogenetic Artemia from seven Chinese locations with different elevations and various ploidies are characterized by phenotypic and morphometric analyses. Our findings show that the studied populations exhibit dissimilar patterns of ovisac. Four phenotypic patterns of furca are qualified and one of them is shared among di‐, tetra‐ and pentaploid Artemia. Results of discriminant analysis based on morphometric data reveal that tetra‐ and pentaploid populations are grouped together, but the Aqqikkol Lake population is clearly differentiated. Previous hypothesis/conclusion that polyploid Artemia are larger than diploids is only partly supported by the present results, which show that pentaploid and tetraploid populations are larger than the mostly diploid populations in terms of the total length, but the body size of the Aibi Lake triploids has not significant difference with the sympatric diploids and the mostly diploid Aqqikkol population that inhabit in very high altitude has the largest body size among all parthenogenetic populations. The founding confirms that body size of Artemia is following with Bergmann's rule. Microsc. Res. Tech. 79:258–266, 2016. © 2016 Wiley Periodicals, Inc.     

Effects of Drying Strategies and Microfibrillated Cellulose Fiber Content on the Properties of Foam-Formed Paper

A novel methodology was used to create a highly porous foam-formed paper that is bonded with highly refined cellulose fiber. In this process, cellulose pulp suspension at various consistencies (0.5, 1.0, 1.5, and 2%) was dispersed in water, followed by foam formation under high shear forces in the presence of a surfactant. Various drying methods were used to achieve foam formation. These included freeze-drying (FD), vacuum-dewatered air-drying (VAD), and dewatered freeze-drying (VFD). Increasing the pulp's consistency and changing the drying techniques from freeze-drying to air-drying resulted in a more compact morphological structure and increased density of foam-formed paper samples. Densification of foam-formed samples was measured using a Dynamic Mechanical Analysis (DMA) machine and a sample with densification at lowest strain value was obtained by a 10 wt% addition of microfibrillated cellulose fiber (MFC). At 10 wt% MFC addition, denser foam-formed paper samples with enhanced microstructure were obtained. Air filtration efficiency and acoustic properties of foam-formed paper were also characterized and optimized by the addition of MFC.     

Hydrothermal and entropy generation specifications of a hybrid ferronanofluid in microchannel heat sink embedded in CPUs

The objective of this numerical work is to evaluate the first law and second law performances of a hybrid nanofluid flowing through a liquid-cooled microchannel heatsink.The water-based hybrid nanofluid includes the Fe_3O_4 and carbon nanotubes(CNTs) nanoparticles.The heatsink includes a microchannel configuration for the flow field to gain heat from a processor placed on the bottom of the heatsink.The effects of Fe_3O_4 concentration(φFe_3O_4),CNT concentration(φ_(CNT)) and Reynolds number(Re) on the convective heat transfer coefficient,CPU surface temperature,thermal resistance,pumping power,as well as the rate of entropy generation due to the heat transfer and fluid friction is examined.The results indicated higher values of convective heat transfer coefficient,pumping power,and frictional entropy generation rate for higher values of Re,φFe_3O_4 and φ_(CNT).By increasing Re,φFe_3O_4 and φ_(CNT),the CPU surface temperature and the thermal resistance decrease,and the temperature distribution at the CPU surface became more uniform.To achieve the maximum performance of the studied heatsink,applying the hybrid nanofluid with low φFe_3O_4 and φ_(CNT) was suggested,while the minimum entropy generation was achieved with the application of nanofluid with high φFe_3O_4 and φ_(CNT).