Edge Intensity Research Articles

An Image Steganography using Particle Swarm Optimization and Transform Domain

As information technology is growing tremendously, one of the major concern is information security. A technique called image steganography is used to provide better security and for safeguarding the information. In image steganography, a secret image is put into recipient image so that only the receiver and sender will be aware of the secret message. Here in this paper, a secure, optimized scheme called particle swarm optimization is used to select the pixel efficiently for embedding the secret image in to cover image. PSO(Particle Swarm Optimization) decides pixel using fitness function which is based on the cost function. Cost function calculates entropy, edge and pixels intensity to evaluate fitness. Also, a technique called discrete wavelet transform has been employed to achieve robustness and statistical undetectability. The main aim of the proposed paper is to make better security and to obtain efficient PSNR and MSE values

Overlapping community detection with least replicas in complex networks

In the context of network theory, overlapping community detection finds communities with certain nodes belonging to multiple communities. In recent decades, many such algorithms have been proposed but suffer from the following limitations: (1) high computational complexity, which limits the applicability of most algorithms in large-scale networks; (2) highly overlapped communities with too many overlapping nodes, which might cause communities to lack unique features because they share many nodes; (3) low steadiness, which means that the divisions found by selected algorithms might differ from time to time; and (4) unidentified nodes, which means a failure to classify every node into communities. To avoid such problems, we propose a novel algorithm in this paper for overlapping community detection with least replicas, i.e., OCDLR. More specifically, first, the algorithm defines the edge intensity to quantify the relationship between each pair of connected nodes, where a higher intensity means closer relationship. Second, the algorithm extracts edges with intensities above a given threshold as skeleton edges and specifies the nodes of skeleton edges as core nodes and others as margin nodes. Third, the process identifies all potential overlapping nodes from the core node set and optimally replicates them, ensuring that replicas remain as far apart as possible but still belong to the core node set. By applying the congregating strategy twice, the algorithm combines different groups of core nodes that are connected by skeleton edges as disjoint initial communities and attaches margin nodes to the nearest communities. The replicas of the same original node that belong to the same community are reassembled as one, and after such adjustments, the number of replicas are minimized, and overlapping communities with the least replicas can be acquired. Experimental results on real networks show the efficiency and accuracy of our method.

A Li K-edge XANES study of salts and minerals.

The first comprehensive Li K-edge XANES study of a varied suite of Li-bearing minerals is presented. Drastic changes in the bonding environment for lithium are demonstrated and this can be monitored using the position and intensity of the main Li K-absorption edge. The complex silicates confirm the assignment of the absorption edge to be a convolution of triply degenerate p-like states as previously proposed for simple lithium compounds. The Li K-edge position depends on the electronegativity of the element to which it is bound. The intensity of the first peak varies depending on the existence of a 2p electron and can be used to evaluate the degree of ionicity of the bond. The presence of a 2p electron results in a weak first-peak intensity. The maximum intensity of the absorption edge shifts to lower energy with increasing SiO2 content for the lithium aluminosilicate minerals. The bond length distortion of the lithium aluminosilicates decreases with increasing SiO2 content, thus increased distortion leads to an increase in edge energy which measures lithium's electron affinity.

Complexities of shrub encroachment: are shrubs important for the maintenance of diversity in Themeda-dominated assemblages on coastal headlands in eastern Australia?

Shrub encroachment is an issue worldwide with consequences which may have both positive and negative outcomes for landscape and community health. Themeda-dominated communities on headlands are listed as endangered within New South Wales, Australia with shrub encroachment listed as threat. Coastal headlands are considered harsh environments and positive effects on species diversity patterns may occur due to variables that ameliorate these conditions or through indirect mechanisms. Shrubs are a natural component of coastal headlands in eastern Australian and tall shrub encroachment may have both positive and negative effects on non-shrub communities. I test whether tall shrubs may have a functional role that positively affects species diversity within and between plots and the distribution of species within Themeda-dominated communities on headlands. 352 2 × 2 m plots were placed on 46 headlands along a 530 km stretch of coastline on the North Coast Bioregion, New South Wales, Australia. Within plots vascular plant species were scored on cover and frequency. Species density, diversity, evenness, turnover and gamma diversity were calculated. Variables tested include cumulative tall shrub height from circular transects at 2, 4 and 8 m from plots, slope, aspect, altitude, ground layer height, distance to closest seaward edge and macropod grazing intensity. Rarefaction was performed on a subset of sites that had no shrubs and sites within shrubs within 8 m of plots. The relative interaction intensity (RII) was calculated for all taxa with more than one observation against plots without shrubs and plots with shrubs within 8 m radius. Analyses were performed using Canonical Correspondence Analysis (CCA) and Generalised Additive Modelling (GAM) on species frequency data. A total of 303 native taxa were recorded within plots. The most significant positive effects on species density, evenness and species accumulation included increasing proximity to, and density of tall shrubs. Tall shrubs may allow direct facilitation of less stress tolerant plants to colonise but may have an indirect interaction by reduction in the dominance of Themeda triandra. Other minor significant variables included distance from headland seaward edge, southern and western facing slopes, higher altitudes and a decrease in ground layer height. 178 (80%) of species were found to have a positive RII score associated with the presence of nearby taller shrubs. Tall shrubs may directly facilitate greater species diversity by ameliorating local conditions and indirectly facilitate by reducing the over-dominance of some taxa. In spite of the positive effect of shrubs on diversity eventually tall shrub encroachment may cause replacement of the Themeda-dominated communities with shrubland. Encroaching taller shrubs are therefore shown to be both of benefit to floristic species diversity at all scales within these Themeda-dominated communities on headlands in eastern Australia but also a potential threat. These results highlight the complex nature of community interactions requiring nuanced and potentially novel approaches to management.

Linking macrodetritivore distribution to desiccation resistance in small forest fragments embedded in agricultural landscapes in Europe

Most of the agricultural landscape in Europe, and elsewhere, consists of mosaics with scattered fragments of semi-natural habitat like small forest fragments. Mutual interactions between forest fragments and agricultural areas influence ecosystem processes such as nutrient cycling, a process strongly mediated by the macrodetritivore community, which is however, poorly studied. We investigated macrodetritivore distribution patterns at local and landscape-level and used a key functional trait (desiccation resistance) to gain mechanistic insights of the putative drivers. Macrodetritivores were sampled in forest edges-centres of 224 European forest fragments across 14 landscapes opposing in land use intensity. We used a multilevel analysis of variance to assess the relative contribution of different spatial scales in explaining activity-density and Shannon-diversity of woodlice and millipedes, together with a model-based analysis of the multivariate activity-density data testing the effect on species composition. Secondly, we tested if desiccation resistance of macrodetritivores varied across communities at different spatial scales using linear mixed effect models. Forest edge-centre and landscape use intensity determined activity-density and community composition of macrodetritivores in forest fragments, while fragment characteristics like size and continuity were relatively unimportant. Forest edges and higher intensity landscapes supported higher activity-density of macrodetritivores and determined species composition. Forest edges sustained woodlouse communities dominated by more drought tolerant species. Landscape use intensity and forest edges are main drivers in macrodetritivore distribution in forest fragments with desiccation resistance a good predictor of macrodetritivore distribution. Key functional traits can help us to predict changes in community structure in changing landscapes.

改进IHS-Curvelet变换融合可见光与红外图像抗晕光方法

In order to solve the problem of driver halation caused by the abuse of high beam lights at night, the anti-halation method of visible and infrared image fusion was proposed based on improved Curvelet transform in IHS color space. The method could effectively express the two-dimensional detail information of the image by improving the Curvelet transform, and improved the image clarity. The proposed fusion strategy of self-adjusting low-frequency coefficient weights could remove the halation information and avoid its participation in the fusion process. The color information in the original image was preserved by combining with the IHS transform to avoid color distortion. Subjective and objective analysis of the experiment results show that the method can eliminate the halation more completely. Compared with IHS-wavelet fusion, standard deviation, average gradient, edge intensity and entropy of the fusion image increase by 47.15%, 53.10%, 52.46% and 4.45%, respectively, its contrast and clarity are significantly enhanced, the details are also more abundant, and the visual effect of the human eye is better. The method is helpful for the driver to observe the road condition ahead, make judgment in advance, eliminate safe hidden trouble and improve the safety of night driving.

Machine Vision Based Image Processing Techniques for Surface Finish and Defect Inspection in a Grinding Process

Inspection of surface finish and defects in a machined surface is critically important for ensuring the functional requirements in high precision applications. This paper presents simple image processing techniques for surface finish and defect inspection of grinding surface. Canny edge detection and histogram analysis were applied for understanding the effect of surface finish on pixel intensity distribution & edge detection using a machine vision system for a mild steel rectangular specimens. The gray scale intensity distribution on the image is observed using pixel level values. Canny Edge detection algorithm is implemented and the results are compared visually to observe the edge detection under various grinding surface conditions. An experimental analysis is presented as a base for further research work on object surface classification under varying surface grinding conditions.

A FUZZY EDGE BASED MULTIFOCUS FUSION

A New method of fusion is presented to find each object present in the image. The proposed algorithm used USAN (univalue segment assimilating nucleus) technique to fuse the high and low intensity edges. The effective way of multi focus fusion is based on the fuzzy edge detection using modified fuzzy membership function. However, the proposed method computes the edge intensity region in an optimal way by using particle swarm optimization (PSO). We conduct experiments on several images and compare with different state of art methods. The effectiveness of the proposed approach outperforms than other methods in each case of performance measures.

Reduced-reference quality assessment of DIBR-synthesized images based on multi-scale edge intensity similarity

Depth-image-based-rendering (DIBR) plays an important role in view synthesis for free-viewpoint videos. The warping process in DIBR causes geometric displacement, which distributes intensively around edges, and the subsequent rendering process results in the impairment of edges. Traditional 2D image quality metrics are limited in the quality evaluation of DIBR-synthesized images. In this paper, we present a reduced-reference quality metric for DIBR-synthesized images by only extracting several feature values, namely multi-scale Edge Intensity Similarity (EIS). The original and synthesized images are first downsampled to generate images with different resolutions. Then an edge detection process is conducted on each scale and the edge intensity is calculated. The similarity of the edge intensity between each downsampled original image and the corresponding synthesized image is computed. Finally, the average similarity is calculated as the quality score of the DIBR-synthesized image. Experiments conducted on IRCCyN/IVC DIBR image and video databases demonstrate that the proposed method overall outperforms traditional 2D and existing DIBR-targeted quality metrics.

Basin Edge Effect on Seismic Ground Response: A Parametric Study for Duzce Basin Case, Turkey

In this study, edge effect on the spatial variation of surface ground motion was evaluated by conducting one (1D) and two-dimensional (2D) dynamic analyses on the numerical model of Duzce basin. Duzce is a province in northwestern Turkey and was hit by a devastating earthquake in November 1999. In order to estimate the seismic behavior of Duzce basin, 1D and 2D dynamic response analyses were carried out on its numerical model by using the seismic bedrock motion data derived from the deconvolution analysis of the N–S component of 1999 Duzce earthquake accelerogram. In addition, a series of different accelerograms and slope values were utilized to investigate the possible effects of change in strong ground motion intensity level and edge geometry on the dynamic response of soil layers over inclined bedrock. The finite element model for the edge section of the flat sedimentary basin was set up by using the 2D shear wave velocity profile, geotechnical and geological site conditions in Duzce. The variation of 2D/1D spectral acceleration ratios and aggravation factors with distance from basin edge was obtained for different period values. The results indicate that the aggravation factors reached their maximum values at a specific zone near basin edge and they generally converged to 1 regardless of the bedrock inclination or period values with increasing distance from the edge section. The highest aggravation factor values were calculated as 2.0–2.5 for the period interval of $$T=$$ 0.2–0.6 s. A relationship was proposed between the aggravation factor and basin edge geometry.

Predictive Factors of Retear in Patients With Repaired Rotator Cuff Tear on Shoulder MRI

This study aimed to find independent prognostic factors related to retear of the rotator cuff tendon in patients with repaired full-thickness supraspinatus tendon tear by evaluation of pre- and postoperative MR images. Shoulder MR images were retrospectively analyzed for 83 patients who had undergone arthroscopic or open rotator cuff repair with acromioplasty for full-thickness supraspinatus tendon tear from April 2014 to March 2015. On preoperative MR images, the type of rotator cuff tear, extent of retraction of torn tendon, anteroposterior (AP) dimension of torn tendon, signal intensity of tear edge, degree of fat infiltration in supraspinatus and infraspinatus muscles, and acromiohumeral interval (AHI) were assessed. Postoperative cuff integrity seen on MR images was classified into five categories according to the Sugaya classification system, and patients were categorized into retear or intact groups. Factors assessed on preoperative MR images were compared between the two groups. The overall retear rate was 57.8%. Significant differences were observed between the retear and intact groups in terms of the mean values of the extent of tendon retraction (20.4 vs 11.7 mm), AP dimension of the tear (16.1 vs 11.4 mm), AHI (6.8 vs 8.7 mm), and degree of fat infiltration of the supraspinatus and infraspinatus muscles (for the supraspinatus muscle, 3, 30, and 15 patients in the retear group vs 5, 27, and three patients in the intact group had Goutallier grade 1, grade 2, and grades 3 and 4 infiltration, respectively; for the infraspinatus muscle, 27, 12, and 9 patients in the retear group vs 29, 5, and one patient in the intact group had Goutallier grade 1, grade 2, and grades 3 and 4 infiltration, respectively). Multivariable analysis revealed that AHI and degree of tendon retraction were independent predictive factors affecting retear of rotator cuff after repair. The retear rate of repaired rotator cuff tendon was about 57.8%. Independent prognostic factors of retear were degree of tendon retraction and AHI on preoperative MR images.

A novel ultra-thin-walled ZnO microtube cavity supporting multiple optical modes for bluish-violet photoluminescence, low-threshold ultraviolet lasing and microfluidic photodegradation

ZnO optical microcavities have shown great promise as a potential core component material/structure for ultraviolet lasers, light-emitting diodes and photonic sensors because of their outstanding optoelectronic properties. Here, we report a novel ultra-thin-walled ZnO (UTW-ZnO) microtube cavity with a wall thickness of ~750 nm, supporting multiple types of optical modes, including in-tube Fabry–Perot modes, in-wall Fabry–Perot modes and wave-guided whispering gallery modes (WG-WGMs). The free-exciton recombination rate and exciton–exciton collisions are promoted in the cavity. The intensities of near-band edge (ultravoilet (UV) light) and X-band (blue light) emission are therefore increased at least one order of magnitude in the temperature range of 0–500 °C. Meanwhile, the temperature-sensitive multicolor luminescence of the UTW-ZnO microtubes in the visible band from near-white to bluish-violet is demonstrated for the first time. Low-threshold UV lasing is also achieved in the UTW-ZnO microtube by WG-WGMs, where the excitation threshold is down to 5.50 μW. Furthermore, light harvesting in the microtube cavity is beneficial to boosting the ZnO catalytic performance for photodegradation of organic dyes. The UTW-ZnO microtube exhibits compatibility to microfluidic channels for recyclable on-chip degradation. The present work provides new opportunities to design novel tubular wide-bandgap semiconductor devices for a variety of optoelectronic applications in micro/nanophotonics.

Edge connection based Canny edge detection algorithm

Double threshold method of traditional Canny operator detects the edge rely on the information of gradient magnitude, which has a lower edge connectivity and incomplete image information. Aiming at this problem, we proposed an edge detection algorithm based edge connection--the Hough Transform based Canny (HT-Canny) edge detection algorithm. HT-Canny algorithm guided by high threshold image, which obtains edge direction through calculating edge endpoint gradient and connects the edge by using the Hough Transform instead of traditional double threshold method. It avoids the limitation of traditional Canny algorithm, which must set the double threshold manually and protect the low intensity edge especially. The experimental results show that HT-Canny algorithm has stronger edge connectivity and can distinguish edge points and non-edge points effectively, which not only retain the advantages of the traditional Canny algorithm but also make the detection result more complete and comprehensive.

Plain and contrast-enhanced chest computed tomography scan findings of pulmonary cryptococcosis in immunocompetent patients.

Pulmonary cryptococcosis is most commonly reported in immunocompromised patients, whereas immunocompetent hosts are rarely affected and may be asymptomatic, resulting in reduced diagnostic performance of computed tomography (CT) imaging. Thus, the aim of the present study was to review the plain and contrast-enhanced chest CT scan findings of primary pulmonary cryptococcosis in immunocompetent patients, with the aim of improving the diagnosis of this type of pulmonary disease. In the present study, a total of 27 immunocompetent patients of clinically confirmed pulmonary cryptococcosis were analyzed retrospectively. Of the 27 patients, 14 patients underwent plain and contrast-enhanced chest CT scans, while 13 patients only underwent plain chest CT scanning. The clinical and imaging characteristics, including the location, shape, size, number, edge and attenuation or intensity of each lesion, in unenhanced and contrast-enhanced CT scans were reviewed. The results indicated that the most common CT finding was pulmonary nodules (40.74%), with multiple nodules (25.93%) being more common compared with solitary nodules (14.81%). The majority of the nodules were poorly defined and inhomogeneous with observed air-bubble sign. Other findings included consolidation (25.93%), ground-glass opacities (GGO; 22.22%) and a mass (11.11%). The halo, air bronchogram and cavity signs were observed more frequently (22.22, 18.52 and 14.81%, respectively). The pulmonary lesions presented a predominant distribution in the lower lung lobes and peripheral area in 55.55 and 74.07% of the cases, respectively. On the contrast-enhanced CT images, the majority of nodules presented ring enhancement with the mean maximal enhancement value of 20.92±5.67 Hu, and masses demonstrated inhomogeneous enhancement with a mean maximal enhancement value of 35.61±8.32 Hu. In conclusion, familiarity with the CT findings and occupational environment exposure history will assist in earlier and easier diagnosis of pulmonary cryptococcosis in immunocompetent patients.

Clinical application of enhanced retinal vasculature visualization using hemoglobin absorbance

PurposeTo develop a digital filter for better visualization of retinal blood vessels and verify its clinical usefulnessMethodsFour‐hundred 24‐bit color fundus images were analyzed and properties of red, green, and blue channels were extracted. Then, using hemoglobin absorption coefficients, the relevant weights for gray‐scale conversion that emphasizes retinal vessels were calculated. To evaluate images, edges were detected via convolutional 2D Laplacian kernel from the processed images, and the number of edges, number of effective edges, and sum of intensities of edges were evaluated. The values of weights for red, green, and blue channels were calculated to be ‐0.0572, 0.7335, and 2.2079, respectively. The number of edges, effective edges, and sum of intensities of edges were all found to be significantly higher in the images processed with the new filter (P < 10‐16). To evaluate the clinical usefulness of the digital filter, 2 individual observers graded 100 photographs from subjects with diabetes mellitus before and after application of newly developed digital filter. Grading was compared with FA findings.ResultsCorrespondence of diabetic retinopathy grading from 2 independent observers were 0.36 and 0.29 before application of digital filter and 0.61 and 0.65 after application of digital filter(kappa value, respectively). Correspondence of presence of diabetic retinopathy from 2 independent observers were 0.69 and 0.69 before application of digital filter and 0.86 and 0.84 after application of digital filter(kappa value, respectively).ConclusionsThe hemoglobin absorbance reinforced the edges of retinal blood vessels, verifying that the new RGB filter can enhance the visualization of retinal vasculature and increase the accuracy of diagnosis.

Image quality enhancement method for on-orbit remote sensing cameras using invariable modulation transfer function.

Remote sensing cameras in the visible/near infrared range are essential tools in Earth-observation, deep-space exploration, and celestial navigation. Their imaging performance, i.e. image quality here, directly determines the target-observation performance of a spacecraft, and even the successful completion of a space mission. Unfortunately, the camera itself, such as a optical system, a image sensor, and a electronic system, limits the on-orbit imaging performance. Here, we demonstrate an on-orbit high-resolution imaging method based on the invariable modulation transfer function (IMTF) of cameras. The IMTF, which is stable and invariable to the changing of ground targets, atmosphere, and environment on orbit or on the ground, depending on the camera itself, is extracted using a pixel optical focal-plane (PFP). The PFP produces multiple spatial frequency targets, which are used to calculate the IMTF at different frequencies. The resulting IMTF in combination with a constrained least-squares filter compensates for the IMTF, which represents the removal of the imaging effects limited by the camera itself. This method is experimentally confirmed. Experiments on an on-orbit panchromatic camera indicate that the proposed method increases 6.5 times of the average gradient, 3.3 times of the edge intensity, and 1.56 times of the MTF value compared to the case when IMTF is not used. This opens a door to push the limitation of a camera itself, enabling high-resolution on-orbit optical imaging.

Robust Real-Time Gradient-based Eye Detection and Tracking Using Transform Domain and PSO-Based Feature Selection

Despite numerous research on eye detection and tracking, this field of study remains challenging due to the individuality of eyes, occlusion, and variability in scale, location, and light conditions. This paper combines a techniques of feature extraction and a feature selection method to achieve a significant increase in eye recognition. Subspace methods may improve detection efficiency and accuracy of eye centers detection using dimensionality reduction. In this study, HoG descriptor is used to lay the ground for BPSO based feature selection. Histogram of Oriented Gradient (HoG) features are used for efficient extraction of pose, translation and illumination invariant features. HoG descriptors uses the fact that local object appearance and shape within an image can be described by the distribution of intensity gradients or edge directions. The method upholds invariance to geometric and photometric transformations. The performance of presented method is evaluated using several benchmark datasets, namely, BioID and RS-DMV. Experimental results obtained by applying the proposed algorithm on BioID dataset show that the proposed system outperforms other eye recognition systems. A significant increase in the recognition rate is achieved when using the combination of HoG descriptor, BPSO, and SVM for feature extraction, feature selection and training phase respectively. The Recognition rate for BioID dataset was 99.6% and the detection time was 15.24 msec for every single frame.

Quantifying Pelvic Periprosthetic Bone Remodeling Using Dual-Energy X-Ray Absorptiometry Region-Free Analysis

The gold standard tool for measuring periprosthetic bone mineral density (BMD) is dual-energy X-ray absorptiometry (DXA). However, resolution of the method is limited due to the aggregation of pixel data into large regions of interest for clinical and statistical analysis. We have previously validated a region-free analysis method (DXA-RFA) for quantitating BMD change at the pixel level around femoral prostheses. Here, we applied the DXA-RFA method to the pelvis, and quantitated its precision in this setting using repeated DXA scans taken on the same day after repositioning in 29 patients after total hip arthroplasty. Scans were semiautomatically segmented using edge detection, intensity thresholding, and morphologic operations, and elastically registered to a common template generated through generalized Procrustes analysis. Pixel-wise BMD precision between repeated scans was expressed as a coefficient of variation %. Longitudinal BMD change was assessed in an independent group of 24 patients followed up for 260 wk. DXA-RFA spatial resolution of 0.31 mm2 provided approximately 12,500 data points per scan. The median data-point precision was 17.8% (interquartile range 14.3%–22.7%). The anatomic distribution of the precision errors showed poorer precision at the bone borders and superior precision to the obturator foramen. Evaluation of longitudinal BMD showed focal BMD change at 260 wk of −26.8% adjacent to the prosthesis-bone interface (1% of bone map area). In contrast, BMD change of +39.0% was observed at the outer aspect of the ischium (3% of bone map area). Pelvic DXA-RFA is less precise than conventional DXA analysis. However, it is sensitive for detecting local BMD change events in groups of patients, and provides a novel tool for quantitating local bone mass after joint replacement. Using this method, we were able to resolve BMD change over small areas adjacent to the implant-bone interface and in the ischial region over 260 wk after total hip arthroplasty.

Urban or rural areas: which types of surrounding land use induce stronger edge effects on the functional traits of tropical forests plants?

AbstractQuestionsWhich types of land use adjacent to Atlantic Tropical Forests induce the strongest edge effects in terms of the functional responses of arboreal and understorey plants? Which functional traits respond to stress imposed by each land‐use type in the two forest layers?LocationFull‐protection conservation areas in the metropolitan region of Recife, Pernambuco State, Brazil.MethodsWe calculated the proportions of species and individuals of woody plants in terms of their functional traits (seed size, maximum height, dispersal syndrome and regeneration strategy) along the edge and in the interior of tropical Atlantic Forest remnants exposed to different degrees of adjacent urbanization along their borders (urban, suburban and rural) by establishing 120 sampling points (60 plots considering the arboreal components and 60 subplots considering woody understorey plants).The degree of urbanization adjacent to the edges of the remnant forests were determined by mapping the sites based on satellite images. The intensities of the edge effects on functional composition, and the differences in the functional traits were assessed using multivariate analysis.ResultsFunctional composition along the edges and within the forest interiors of remnants with the highest densities of urban areas around them demonstrated the greatest variability of both the arboreal and understorey components. The arboreal component of the forest sites adjacent to rural areas (intense agricultural activities) tended to demonstrate intermediate intensity edge effects. Species showing shade intolerance, with smaller maximum heights, producing small seeds and with abiotic dispersion were present in high proportions in forests bordering heavily urbanized areas. Biotic dispersal predominated in the arboreal component of the rural remnant.ConclusionsFrom a functional point of view, the forest with the most highly urbanized border is more impacted by edge effects than forests bordering on suburban or rural areas. Nonetheless, in an urban–rural gradient, intense agricultural activity was observed to create intermediate pressure in terms of the intensities of its edge effects. These edge effects differentially impact the functional traits of the arboreal and understorey components, influencing different traits, depending on the type of border.

Oxide ion diffusion mechanism related to Co and Fe ions in (Ba0.5Sr0.5)(Co0.8Fe0.2)O3−δ using in-situ X–ray absorption spectroscopy

The time changes of the white line and pre–edge intensities of Co and Fe K–edge in (Ba0.5Sr0.5)(Co0.8Fe0.2)O3−δ (BSCF) were observed to estimate the oxide ion diffusion related to Co and Fe ions by using in−situ X–ray absorption spectroscopy (XAS) during oxidation. The 20μm self–standing BSCF film was prepared for in−situ XAS measurements. The time changes of absorption were fitted to the exponential decay function with two terms. The longer relaxation time (τ), related to the oxide ion diffusion during the oxidation of BSCF, is dependent on temperature. The oxide ion diffusion coefficients (D) were calculated from the τ s estimated by in−situ XAS. The values of the activation energy (Ea) for D related to Co K–edge white line, Co pre–edge, and Fe pre–edge were 1.8–2.0eV. The value of Ea for D related to Fe K–edge white line, however, was higher than other absorption values at approximately 2.3eV. We discussed the oxide ion diffusion mechanism related to Co and Fe ions in BSCF using in−situ XAS.