Use of satellite-derived emissivity to detect coalfire-related surface temperature anomalies in Jharia coalfield,India

Among natural geo-hazards, spontaneous combustion of coal is unique in nature but common in most coal-producing countries. Coalfires can occur in coal seams and stockpiles of coal at ambient temperature in certain conditions, e.g. those concerning coal type, exposed area and moisture content. Once started, coalfires are difficult to extinguish and sometimes cannot be controlled. In addition to burning millions of tonnes of coal, the fires have enormous negative impacts on local and global environments. In the field of coalfire study, remote sensing is used as a powerful tool to detect and monitor coalfires. Nevertheless, most remote-sensing coalfire studies are based on a fixed emissivity (0.95 or 0.96) which is contrary to the real representation of the Earth's surface. In this research, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER)-derived emissivity was used to detect coalfire-related surface anomalies in an Indian coal mining region. Later, the temperature anomalies detected were validated with ground truth data. Additionally, the ASTER-derived emissivity value was used to extract surface temperatures from Landsat Enhanced Thematic Mapper Plus (ETM+) thermal infrared (TIR) data.     

Probing the interaction of benzo[a]pyrene adducts and metabolites with monoclonal antibodies using fluorescence line-narrowing spectroscopy

A new approach for studying antibody-antigen interactions of DNA adducts and metabolites of polycyclic aromatic hydrocarbons (PAHs) is demonstrated in which fluorescence line-narrowing spectroscopy (FLNS) is used. It is based on the fact that in an FLN spectrum the relative intensities of the line-narrowed bands (that correspond to the excited-state vibrations) are, in general, strongly dependent on the local environment of the fluorophore. Information on the nature of the interactions can be obtained by comparing the FLN spectra of the antigen-antibody complexes to the spectra of the antigen in different types of solvents (H-bonding, aprotic, and pi-electron-containing solvent molecules) recorded under the same conditions. The antigens used were the DNA adduct 7-(benzo[a]pyren-6-yl)guanine (BP-6-N7Gua) and the metabolite (+)-trans-anti-7,8,9,10-benzo[a]pyrenetetrol (BP-tetrol) of benzo[a]pyrene; two monoclonal antibodies (MAbs) have been developed to selectively bind these compounds. It is shown that, for BP-tetrol, H-bonding solvents have a pronounced effect on the FLN spectra. The presence of pi electrons in the solvent molecules results in relatively small but still significant changes in the spectra. When BP-tetrol is bound to its MAb, however, neither of these effects is observed; its spectrum is very similar to the one obtained with an aprotic solvent, methylcyclohexane. Therefore, we can conclude that this MAb has an internal binding site in which the interaction with BP-tetrol is of a hydrophobic character. For BP-6-N7Gua, however, there is a strong effect of the presence of pi electrons in the solvent molecules. The FLN spectrum of this antigen bound to its MAb is very similar to its spectrum in acetone, indicating that pi-pi interactions play an important role in the binding.     

Mechanism of the potassium catalysed gasification of carbon in CO2

The literature on the potassium catalysed gasification of carbon in CO₂ is critically reviewed with respect to the mechanism and the experimental ‘facts’ relevant to the mechanistic considerations. It is concluded that bulk intercalation compounds (C₈K, C₂₄K, etc.) are not present under gasification conditions; also other metallic K-species are not the major species during gasification. It is shown that the catalytic activity can be attributed to an oxygen transfer cycle with either reduction of carbon or decomposition of the oxygenated complexes as the rate determining step. In this catalytic cycle only oxidic potassium species are involved.     

Using zero configuration technology for IP addressing in optical networks

Host configuration in optical networks is usually done by hand. In this paper we propose to use zero configuration techniques, including self-assigned IP addresses and multicast DNS to do this automatically. The proposed technology is designed for small networks without central control, and can be applied to optical private networks as long as there is no router in between the end-hosts.     

Formation of intercalate-like structures by heat treatment of K2CO3-carbon in an inert atmosphere

Treatment of K₂CO₃-activated carbon and K₂CO₃-coal in a nitrogen flow at 1100 K results in the formation of metallic potassium. X-ray analysis revealed that the heat-treated samples have structures similar to those of potassium-graphite intercalation compounds. Potassium acts probably as a graphitizing agent. By heat treatment of K₂CO₃-graphite under the same conditions metallic potassium was not formed and neither could intercalation structures be detected by X-ray analysis.     

Multiscale characterization of pathological bone tissue

Bone is a complex natural material with a complex hierarchical multiscale organization, crucial to perform its functions. Ultrastructural analysis of bone is crucial for our understanding of cell to cell communication, the healthy or pathological composition of bone tissue, and its three-dimensional (3D) organization. A variety of techniques has been used to analyze bone tissue. This article describes a combined approach of optical, scanning electron, and transmission electron microscopy for the ultrastructural analysis of bone from the nanoscale to the macroscale, as illustrated by two pathological bone tissues. By following a top-down approach to investigate the multiscale organization of pathological bones, quantitative estimates were made in terms of calcium content, nearest neighbor distances of osteocytes, canaliculi diameter, ordering, and D-spacing of the collagen fibrils, and the orientation of intrafibrillar minerals which enable us to observe the fine structural details. We identify and discuss a series of two-dimensional (2D) and 3D imaging techniques that can be used to characterize bone tissue. By doing so we demonstrate that, while 2D imaging techniques provide comparable information from pathological bone tissues, significantly different structural details are observed upon analyzing the pathological bone tissues in 3D. Finally, particular attention is paid to sample preparation for and quantitative processing of data from electron microscopic analysis.     

Grip to the Colon by Means of Macroscopic Adhesion-Controlled Friction

Manipulating friction without applying high normal forces is important for an intestine inspection and intervention device in order to eliminate the risk of tissue damage. One possible solution is to generate friction by means of adhesive forces. The adhesive forces should be high to offer sufficient grip without needing high normal forces. The generated friction is then called adhesion-controlled and depends on the size of the area in contact. Adhesion-controlled friction is well known to be dominant at microscopic and molecular levels. According to this paper, adhesion-controlled friction can be applicable on the macroscopic scale as well and, more specifically, within a range of forces in which friction is usually considered to be load-controlled. The intestine inspection and intervention device manipulates the friction with the colonic wall by means of mucoadhesive films. In this way, grip with high static friction is achieved without the need to apply high normal forces and friction is altered by changing the size of the area of the mucoadhesive film. Friction theories on different scales are revisited and considered in order to understand the dominant phenomena and the principles associated with this macroscopic adhesion-controlled friction.     

System calibration and statistical image reconstruction for ultra-high resolution stationary pinhole SPECT

For multipinhole single-photon emission computed tomography (SPECT), iterative reconstruction algorithms are preferred over analytical methods, because of the often complex multipinhole geometries and the ability of iterative algorithms to compensate for effects like spatially variant sensitivity and resolution. Ideally, such compensation methods are based on accurate knowledge of the position-dependent point spread functions (PSFs) specifying the response of the detectors to a point source at every position in the instrument. This paper describes a method for model-based generation of complete PSF lookup tables from a limited number of point-source measurements for stationary SPECT systems and its application to a submillimeter resolution stationary small-animal SPECT system containing 75 pinholes (U-SPECT-I). The method is based on the generalization over the entire object to be reconstructed, of a small number of properties of point-source responses which are obtained at a limited number of measurement positions. The full shape of measured point-source responses can almost be preserved in newly created PSF tables. We show that these PSFs can be used to obtain high-resolution SPECT reconstructions: the reconstructed resolutions judged by rod visibility in a micro-Derenzo phantom are 0.45 mm with 0.6-mm pinholes and below 0.35 mm with 0.3-mm pinholes. In addition, we show that different approximations, such as truncating the PSF kernel, with significant reduction of reconstruction time, can still lead to acceptable reconstructions.