Spatial Distribution Of Components Research Articles

The spatial distribution of components in Moringa oleifera (Lam) seed by matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI)

In this paper, 70 % methanol was used as solvent to extract the principal components from Moringa oleifera (Lam) seed with the ratio (w/v, 1:10) by ultrasonic-assisted extraction. The extract in Lam seed was detected by high resolution mass spectrometry and MS/MS spectra. The result suggests that there are three principal components including malic acid, d-trehalose and 4-(α-L-rhamnopyranosyloxy) benzyl glucosinolate in this extract. Based on this result, the spatial distribution of these components in Lam seed was visually obtained by matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). There is much malic acid in the center of endosperm in Lam kernel and little in the shell of Lam seed. d-trehalose is mainly distributed in the seed coat of Lam seed, and almost no d-trehalose is distributed in the kernel of Lam seed. 4-(α-L-rhamnopyranosyloxy) benzyl glucosinolate is distributed in the seed coat and endosperm of Lam seed. The relative content of this compound in the seed coat of Lam seed is much higher than that in the endosperm. The result further suggests that the different component in Lam seed is distributed in different part. This study can provide some valuable reference for efficient extracting active components from Lam.

Development and application of a social vulnerability index (SOVI) to landslide risk analysis in ribeira medium valley, Brazil

In the last decades, the frequency and intensity of natural disasters in Brazil has increased, resulting in substantial economic, environmental, and social damage. Knowing the specific vulnerabilities of populations exposed to risks reflects on their disaster preparedness, response, and recovery capacities. However, social vulnerability studies in Brazil are still incipient. This study developed a Social Vulnerability Index (SoVI) for the Ribeira Medium Valley to fill this gap. The region is highly susceptible to landslides, and is one of the most impoverished and underdeveloped regions of the state of São Paulo, with a predominantly rural population. The index was composed by selecting 30 variables from 373 census sectors. Principal Component Analysis (PCA) was used to extract seven principal components, accounting for 71.64% of the data variability. The obtained SoVI scores were mapped and subsequently applied in a risk analysis. The most vulnerable municipalities were identified, and each vulnerability component's spatial distribution was visualized. It was also noted that the areas most vulnerable to landslides are also the most socially vulnerable. The results of this study can steer the government towards actions aimed at reducing social vulnerability. They may also help in developing disaster risk mitigation strategies.

Data processing of three-dimensional vibrational spectroscopic chemical images for pharmaceutical applications

Vibrational spectroscopic chemical imaging is a powerful tool in the pharmaceutical industry to assess the spatial distribution of components within pharmaceutical samples. Recently, the combination of vibrational spectroscopic chemical mapping with serial sectioning has provided a means to visualise the three-dimensional (3D) structure of a tablet matrix. There are recognised knowledge gaps in current tablet manufacturing processes, particularly regarding the size, shape and distribution of components within the final drug product. The performance of pharmaceutical tablets is known to be primarily influenced by the physical and chemical properties of the formulation. Here, we describe the data processing methods required to extract quantitative domain size and spatial distribution statistics from 3D vibrational spectroscopic chemical images. This provides a means to quantitatively describe the microstructure of a tablet matrix and is a powerful tool to overcome knowledge gaps in current tablet manufacturing processes, optimising formulation development.

Uncovering the Promotion of CeO2 /CoS1.97 Heterostructure with Specific Spatial Architectures on Oxygen Evolution Reaction.

Structural engineering and compositional controlling are extensively applied in rationally designing and fabricating advanced freestanding electrocatalysts. The key relationship between the spatial distribution of components and enhanced electrocatalysis performance still needs further elaborate elucidation. Here, CeO2 substrate supported CoS1.97 (CeO2 -CoS1.97 ) and CoS1.97 with CeO2 surface decorated (CoS1.97 -CeO2 ) materials are constructed to comprehensively investigate the origin of spatial architectures for the oxygen evolution reaction (OER). CeO2 -CoS1.97 exhibits a low overpotential of 264mV at 10mAcm-2 due to the stable heterostructure and faster mass transfer. Meanwhile, CoS1.97 -CeO2 has a smaller Tafel slope of 49mVdec-1 through enhanced adsorption of OH- , fast electron transfer, and in situ formation of Co(IV)O2 species under the OER condition. Furthermore, operando spectroscopic characterizations combined with theoretical calculations demonstrate that spatial architectures play a distinguished role in modulating the electronic structure and promoting the reconstruction from sulfide to oxyhydroxide toward higher chemical valence. The findings highlight spatial architectures and surface reconstruction in designing advanced electrocatalytic materials.

Multiscale imaging and transport modeling for fuel cell electrodes

Abstract

Infrared Microscopy as a Probe of Composition within a Model Biofuel Cell Electrode Prepared from Trametes versicolor Laccase

AbstractInfrared microscopy was applied in the study of laccase biofuel cell electrodes that demonstrated high current and power densities traceable to the use of a low equivalent weight (EW), short side chain (Aquivion) ionomer in the catalyst layer. The electrodes were prepared from a biocatalyst ink composed of orientation‐directing anthracene‐modified multi‐walled carbon nanotubes (An‐MWCNTs) in a dispersion of ionomer exchanged by hydrophobic cations. The ink was applied to an electronically conductive carbon felt support that was hot‐pressed to a Nafion‐NRE 212 (51 μm thickness) membrane, forming the framework for an air‐breathing biofuel cell cathode. Infrared microscopy sampling was performed with the use of a micro‐attenuated total reflection probe that enabled spectra to be recorded from ∼32 μm diameter circular spatial regions on the materials investigated. Sensitivity to deformation of the soft polymer membrane‐based materials was assessed through trial experiments on pure membrane samples before approaching the compositionally more complex biofuel cell electrodes. In studies of laccase cathodes, infrared spectral features of enzyme, buffer anions and surrounding An‐MWCNTs were identified. Heterogeneity in the spatial distribution of components and unexpected bands traceable to insoluble copper salts were detected. The results suggest directions for improving electrode activity and bring to light needs for advancing quantitative interpretations.

Distinctive Features of the Distributions of the Body Force Produced by a Plasma Actuator

Basing upon the assumption on the solenoidality of the field of the time-average body force produced by a surface dielectric barrier discharge analytical expressions for the spatial distributions of the components of this force are proposed. The calculations of the dischargegenerated near-surface jet are in good agreement with the experiment. The distinctive features of spatial distributions of the body force components calculated from the data of the velocity field measurements are physically explained.

Dynamic control of the location of nanoparticles in hybrid co-assemblies.

We herein demonstrated an approach to control the spatial distribution of components in hybrid microspheres. Hybrid core-shell structured microspheres (CSMs) prepared through co-assembly were used as starting materials, which are comprised of anthracene-ended hyperbranched poly(ether amine) (AN-hPEA) in the shell and crystallized anthracene containing polyhedral oligomer silsesquioxane (AN-POSS). Upon thermal annealing at a temperature higher than the melting point of AN-POSS, the diffusion of AN-POSS from the core to the shell of CSM leads to a transition of morphology from the core-shell structure to core-transition-shell to the more stable homogeneous morphology, which has been revealed by experimental results of TEM and DSC. The mechanism for the morphology transition of CSM induced by the diffusion of AN-POSS was disclosed by a dissipative particle dynamics (DPD) simulation. A mathematical model for the diffusion of POSS in the hybrid microsphere is established according to Fick's law of diffusion and can be used to quantify its distribution in CSM. Thus, the spatial distribution of POSS in the microsphere can be controlled dynamically by tuning the temperature and time of thermal annealing.

Abstract 3963: New software for imaging mass spectrometry data

Abstract Imaging mass spectrometry (IMS) is a molecular imaging technique for various molecules such as compounds, metabolites and proteins to visualize spatial distribution of these components in a tissue sample. In recent years, the measurement of the spatial distribution of components using IMS technique is being carried out intensively in many fields including pathology and drug discovery. Although the importance of IMS has been recognized widely, there are not so many efficient software programs to handle these kinds of data because of the difficulty in treating huge amount of spectra data from many spots, which sometimes amounts to tens of thousands. In this presentation we introduce new software we developed and report its performance. In order to correspond to various purposes, the software was made to consist of four programs as shown below. They achieve quick, automatic, and comprehensive analyses of the important peaks for the first time in the world. To detect important peaks of bio-molecules in each spectrum from mass spectrometry, we first developed a high-speed program for peak picking using a common peak method for IMS data, named IMS Convolution (IMSC). Once some regions of interests (ROI) such as cancer, interstitial and normal regions in a tissue sample are specified through graphical interface program, common peaks in each ROI are automatically detected by IMS convolution. Users can modify a definition of a threshold of common peaks easily, and the IMSC software picks up revised common peaks very quickly. Furthermore, we developed three more programs, named Spatial Peak Detectors (SPeaD) -1, 2 and 3, which use peak picking results by the IMSC. SPeaD-1 is for detecting a small set of peaks and it can discriminate two or more ROIs based on a method from machine learning theory. SPeaD-2 is for detecting cell specific peaks without ROI information. Cancer specific small molecules can be detected when cancer cells are distributed individually in normal tissue. SPeaD-3 is for detecting region specific peaks without ROI information. SPeaD-3 picks up all peaks of the same mass expressed in a clustered region defined by sets of adjacent spots. In evaluating the performance of the software, we used quasi-samples for IMSC and SPeaD-1 and cancer tissue samples for SPeaD-3. IMSC detects all the peaks beyond the noise level. Computation time is within 10 minutes for the data of ANALYZE format file size about 2.5GB with 62,500 (= 250 x 250) spots and with the range of m/z 650-1500. A workstation used for the analysis is equipped with Xeon E5504 CPU (2.0GHz) and 3GB memory. For SPeaD programs, computation time depends on the number of spots and m/z range but falls within about 30 minutes. Furthermore, we analyzed IMS data for hepatic micrometastasis of human colon cancer xenografts in superimmunodeficient NOG mice. Some specific bio-molecules of hepatic micrometastasis were detected quickly and automatically. Further details are given in the presentation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3963. doi:1538-7445.AM2012-3963

Dynamics of codeposition of metals inside porous electrode operating in direct-flow mode

Using an extended dynamic model of liquid flow-through porous electrode (PE), the effect of kinetics of deposition of individual components and conditions of potentiostatic electrolysis on the dynamics and final parameters (the cathodic deposit weight, the ratio between the amounts of components, and the spatial distribution of components) of codeposition of two metals M1 and M2 is studied. An equipotential PE operating in the direct-flow mode in the absence of anodic dissolution of electronegative component M2 is considered. The effects of concentration, exchange currents, a difference between the equilibrium potentials M1 and M2, a prescribed voltage on PE, and solution flow velocity and direction are analyzed. It is shown that, for this version of codeposition of metals, the rates of M1 and M2 deposition averaged over the PE width are constant in time. However, this does not mean that their local deposition rates are constant. The general tendency is that the metal deposition rate on the rear part of PE decreases with the time, whereas the deposition rate on the frontal zone of PE, which is closer to the anode, increases. As a result, the final profiles for M1 and M2, which are calculated for equal deposition times taking into account and ignoring the redistribution of current during the deposition, differ essentially.

A Method of 3D Model Retrieval by the Spatial Distributions of Components

3D shape analysis is a key problem for 3D model retrieval.In this paper,a shape signature describing the spatial distributions of 3D model's components is proposed.The primary motivation of the approach is to emphasize the object's structural attributes due to human vision theories.Firstly,a model is decomposed into several meaningful components,each of which is represented by a sub-mesh,then the component's mass center and percentage of the surface area are combined to form a component feature,and finally a set of component features satisfing the specified conditions are used as the shape signature ofa 3D model.Based the signature,an approach of 3D model retrieval is presented.It performs well despite the presence of different resolutions and connectivity,and is fast when measuring shape similarity.Experimental results demonstrate the ability of the proposed signature to retrieval 3D modes.

Spatial Variability of Fine Particle Mass, Components, and Source Contributions during the Regional Air Pollution Study in St. Louis

Community time-series epidemiology typically uses either 24-hour integrated particulate matter (PM) concentrations averaged across several monitors in a city or data obtained at a central monitoring site to relate PM concentrations to human health effects. If the day-to-day variations in 24-hour integrated concentrations differ substantially across an urban area (i.e., daily measurements at monitors at different locations are not highly correlated), then there is a significant potential for exposure misclassification in community time-series epidemiology. If the annual average concentration differs across an urban area, then there is a potential for exposure misclassification in epidemiologic studies that use annual averages (or multi-year averages) as an index of exposure across different cities. The spatial variability in PM2.5 (particulate matter < or = 2.5 microm in aerodynamic diameter), its elemental components, and the contributions from each source category at 10 monitoring sites in St. Louis, Missouri were characterized using the ambient PM2.5 compositional data set of the Regional Air Pollution Study (RAPS) based on the Regional Air Monitoring System (RAMS) conducted between 1975 and 1977. Positive matrix factorization (PMF) was applied to each ambient PM2.5 compositional data set to estimate the contributions from the source categories. The spatial distributions of components and source contributions to PM2.5 at the 10 sites were characterized using Pearson correlation coefficients and coefficients of divergence. Sulfur and PM2.5 are highly correlated elements between all of the site pairs Although the secondary sulfate is the most highly correlated and shows the smallest spatial variability, there is a factor of 1.7 difference in secondary sulfate contributions between the highest and lowest site on average. Motor vehicles represent the next most highly correlated source component. However, there is a factor of 3.6 difference in motor vehicle contributions between the highest and lowest sites. The contributions from point source categories are much more variable. For example, the contributions from incinerators show a difference of a factor of 12.5 between the sites with the lowest and highest contributions. This study demonstrates that the spatial distributions of elemental components of PM2.5 and contributions from source categories can be highly heterogeneous within a given airshed and thus, there is the potential for exposure misclassification when a limited number of ambient PM monitors are used to represent population-average ambient exposures.

Westward drift in secular variation of the main geomagnetic field inferred from IGRF

Westward drift is apparent not only in the Main Geomagnetic field (MG-field) but also in its Secular Variation (SV-field). The eighth generation of International Geomagnetic Reference Field (IGRF) is used in this paper to study westward drift in the SV-field. The magnetic potential of the SV-field shows a simple spatial distribution and steady variation tendency. An average westward drift rate (0.43 degree/year) is obtained from the SV potential for 1900–2005, which is much greater than the slow westward drift of the MG-field itself (about 0.15 degree/year) for the same period. Magnetic components Y and Z of the SV-field show complicated patterns, from which the average rates of westward drift are roughly estimated as 0.39 degree/year and 0.43 degree/year, respectively. The spatial distribution of component X shows much more complicated pattern with many small-scale vertices, especially for the period 1940–1960, giving a larger drift rate (0.51 degree/year). The unusual behaviors of the high-degree Gauss coefficients in IGRF 1945, 1950 and 1955 slightly affect the spatial pattern of the potential, although they greatly distort the distribution of components X, Y and Z.

The Sandwich Injection Moulding Technology—Effects and Limiting Quantities for the Spatial Distribution of the Components

The factors influencing the spatial distribution of the core component can be divided into geometric, material and process parameters. The distribution of the components is substantially determined by the viscosities of both components, the viscosity ratio of the core and skin melt, the length of the simultaneous phase and the speed of the flow front. In order to describe the layer thickness formation and the melt flow instabilities new models are introduced. They are based on empirically determined interrelations of individual limiting quantities and allow the description of the essential effects of the melt flow during the mould filling process.

Spatial Distribution of Chemical Components in Aerosol Particles as Determined from Secondary Electron Yield Measurements: Implications for Mechanisms of Multicomponent Aerosol Crystallization

Secondary electron yield measurements were used to determine the distribution of chemical components in multicomponent aerosol particles formed by crystallization from aqueous solution droplets. Yield measurements were made by measuring the charge acquired by a beam of particles as they passed through an electron beam (100–600 eV energy) inside a high-vacuum apparatus. Yields were sufficiently different for certain compounds that measurements made on two-component particles could be used to obtain information on the spatial distribution of components. Variations in chemical composition as a function of depth beneath the particle surface were ascertained from the energy dependence of the measured yields, since the electron penetration depth, and therefore the probe depth, increases with electron energy. The results for mixed NaCl–NH4Cl particles indicate that the distribution of components within these particles is relatively homogeneous, while measurements made on mixed NaCl–NaNO3particles are indicative of particles having a heterogeneous core–shell morphology. Results for mixed Na2SO4–(NH4)2SO4particles are ambiguous, probably because of the complexity of the phase diagram of this system. It appears that the mechanism by which aerosol particles crystallize, and therefore the resulting distribution of chemical components within particles, is strongly dependent on particle composition and environmental variables.

Application to groundwater modelling of the Roermond area, The Netherlands

Abstract The method of regional hydrological systems analysis is illustrated by groundwater flow systems modelling of the Roermond area (240 km2) in the south-east of the Netherlands. The systems analysis is divided into two main phases; (1) identification of infiltration and exfiltration system components and (2) identification of the total system configuration and operation. Remotely-sensed data and a geographical information system proved to be valuable tools for the delineation and quantification of the hydrological system components. Based on the known spatial distribution of components the system configuration and operation is estimated, thus serving as a reference for subsequent modelling of regional hydrological flow systems.