Theory for microwave thermal emission from a layer of cloud or rain

Microwave thermal emission from a layer of cloud or rain consisting of spherical particles has been investigated. Scattering effects are studied in great detail with both numerical and analytical approaches. In the absence of ground emission, it is found that scattering induces brightening for optically thin layers and vice versa for optically thick layers. As a function of observation angle brightening occurs near nadir while darkening occurs at large angles in the case of small optical thickness. For large optical thickness, darkening occurs at all angles because of backscattering effects. When the layer of cloud or rain is above an air layer and an ocean surface at a higher temperature, it is found that the darkening effect at large optical thickness is much more pronounced. The darkening effect is also larger for vertical polarizations because the ocean emits more vertically polarized components. The effect of thermal emission and molecular absorption by atmospheric gases is also taken into account. Results obtained from analytical formulas under single scatteirng assumptions are compared and illustrated.     

Application of Strong Fluctuation Random Medium Theory to Scattering from Vegetation-Like Half Space

A model for vegetation scatter is developed using the theory of electromagnetic wave propagation in random medium with strong permittivity fluctuations. In applying the strong fluctuation theory, the singularity of the dyadic Green's function is taken into account. Backscattering coefficients are computed using the distorted Born approximation and illustrated as a function of incidence angle, frequency and moisture content of the vegetation. The mixing formula of the de Loor [28] was used in estimating the permittivity of leaves. The correlation function of Fung and Fung [18], and Fung and Ulaby [19] is used for the random medium.     

High-affinity capture of proteins by diamond nanoparticles for mass spectrometric analysis

Carboxylated/oxidized diamond nanoparticles (nominal size 100 nm) exhibit exceptionally high affinity for proteins through both hydrophilic and hydrophobic forces. The affinity is so high that proteins in dilute solution can be easily captured by diamonds, simply separated by centrifugation, and directly analyzed by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS). No preseparation of the adsorbed molecules from diamonds is required for the mass spectrometric analysis. Compared to conventional MALDI-TOF-MS, an enhancement in detection sensitivity by more than 2 orders of magnitude is achieved for dilute solution containing cytochrome c, myoglobin, and albumin because of preconcentration of the probed molecules. The lowest concentration detectable is 100 pM for a 1-mL solution. Aside from the enhanced sensitivity, the overall performance of this technique does not show any sign of deterioration for highly contaminated protein solutions, and furthermore, no significant peak broadening and band shift were observed in the mass spectra. The promise of this new method for clinical proteomics research is demonstrated with an application to human blood serum.     

Plasma phospholipid metabolic profiling and biomarkers of type 2 diabetes mellitus based on high-performance liquid chromatography/electrospray mass spectrometry and multivariate statistical analysis

Liquid chromatography/mass spectrometry (LC/MS) followed by multivariate statistical analysis has been successfully applied to the plasma phospholipids metabolic profiling in type 2 diabetes mellitus (DM-2). Principal components analysis and partial least-squares discriminant analysis (PLS-DA) models were tested and compared in class separation between the DM2 and control. The application of an orthogonal signal correction filtered model highly improved the class distinction and predictive power of PLS-DA models. Additionally, unit variance scaling was also tested. With this methodology, it was possible not only to differentiate the DM2 from the control but also to discover and identify the potential biomarkers with LC/MS/MS. The proposed method shows that LC/MS combining with multivariate statistical analysis is a complement or an alternative to NMR for metabonomics applications.     

Fe2+/HClO氧化处理β-萘酚模拟废水的研究

以NaClO在酸性水溶液中生成的HClO代替Fenton试剂中的氧化剂H2O2,在Fe^2 的作用下对β—萘酚模拟废水进行处理,结果表明：使用HClO代替H2O2处理β—萘酚模拟废水能够取得更好的效果;废水pH、FeSO4和NaClO的投加量对降解效果有很大影响;光照可以促进β—萘酚的降解,60min后CODCr去除率可达60．8％,而同样条件下无光照时CODCr去除率仅为45．1％。     

Associations between diet and disease activity in ulcerative colitis patients using a novel method of data analysis

Background  

The relapsing nature and varying geographical prevalence of ulcerative colitis (UC) implicates environmental factors such as diet in its aetiology.     

Production, purification, and characterization of micrococcin GO5, a bacteriocin produced by Micrococcus sp. GO5 isolated from kimchi

Strain GO5, a bacteriocin-producing bacterium, was isolated from green onion kimchi and identified as Micrococcus sp. The bacteriocin, micrococcin GO5, displayed a broad spectrum of inhibitory activity against a variety of pathogenic and nonpathogenic microorganisms, as tested by the spot-on-lawn method; its activity spectrum was almost identical to that of nisin. Micrococcin GO5 was inactivated by trypsin (whereas nisin was not) and was completely stable at 100 degrees C for 30 min and in the pH range of 2.0 to 7.0. Micrococcin GO5 exhibited a typical mode of bactericidal activity against Micrococcus flavus ATCC 10240. It was purified to homogeneity through ammonium sulfate precipitation, ultrafiltration, and CM-Sepharose column chromatography. The molecular mass of micrococcin GO5 was estimated to be about 5.0 kDa by tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis and in situ activity assay with the indicator organism. The amino acid sequence of micrococcin GO5 lacks lanthionine and beta-methyllanthionine and is rich in hydrophobic amino acids and glycine, providing the basis for the high heat stability of this bacteriocin. The N-terminal amino acid sequence of micrococcin GO5 is Lys-Lys-Ser-Phe-Cys-Gln-Lys, and no homology to bacteriocins reported previously was observed in the amino acid composition or N-terminal amino acid sequence. Based on the physicochemical properties, small molecular size, and inhibition of Listeria monocytogenes, micrococcin GO5 has been placed with the class II bacteriocins, but its broad spectrum of activity differs from that of other bacteriocins in this class.     

Modal approach to scattering of electromagnetic waves by a conducting tape helix

Electromagnetic wave scattering by a tape helix of infinite extent is studied by using Floquet wave expansions for the guided modes and scattered fields. The solution reduces to earlier results as a special limiting case for normal incidence on a sheath helix. The current induced on an infinite helix computed by the presented technique bears close resemblance to the current induced on a long but finite helix as computed by Galerkin's method. The spatial frequency spectrum of the induced current is plotted to show the dominance of the spatial harmonics that are phase matched with the guided modes of the helix. Azimuthal patterns of the scattered field are included to illustrate that interference increases as the diameter of the helix is increased.     

Application of the radio-frequency interferometry method to a stratifield anisotropic medium

Interference patterns are calculated for a horizontal dipole laid on the surface of a stratified medium with both anisotropic permittivity and permeability tensors. The anisotropy in permitivity affectts the radiated fields in the endfire direction, and the anisotropy in permeability affects those in the broadside direction. The effects of anisotropy are illustrated for various cases.     

A Simple Relation between Active And Passive Microwave Remote Sensing Measurements of Earth Terrain

A simple approximate relation between backscattering coefficient and emissivity measurements is derived. The relation is applicable to active and passive microwave remote sensing of earth terrain where volume scattering plays a dominant role. From the relation, one can obtain a rough estimate of the backscattering coefficient from the emissivity and vice versa. Such estimation is useful in checking experimental measurements and also helps to ascertain the validity of theoretical models. It also safeguards against obtaining arbitrarily high values for both backscattering coefficients and emissivities.