High-resolution Image Analysis Research Articles

Intelligent system for agricultural crops defective areas monitoring and visualization based on spectral analysis of satellite high-resolution images

The article deals with the aspects of designing and software implementation of an intelligent system for monitoring and visualizing defective areas of agricultural crops based on the spectral analysis of high-resolution satellite images. The structure of the designed intelligent system, modules and procedures used in its software implementation, as well as a UML-diagram of user interaction with the components of the software system are presented.

Enhanced Diagnosis of Pneumothorax with an Improved Real-Time Augmentation for Imbalanced Chest X-rays Data Based on DCNN.

Pneumothorax is a common pulmonary disease that can lead to dyspnea and can be life-threatening. X-ray examination is the main means to diagnose this disease. Computer-aided diagnosis of pneumothorax on chest X-ray, as a prerequisite for a timely cure, has been widely studied, but it is still not satisfactory to achieve highly accurate results. In this paper, an image classification algorithm based on the deep convolutional neural network (DCNN) is proposed for high-resolution medical image analysis of pneumothorax X-rays, which features a Network In Network (NIN) for cleaning the data, random histogram equalization data augmentation processing, and a DCNN. The experimental results indicate that the proposed method can effectively increase the correct diagnosis rate of pneumothorax, and the Area under Curve (AUC) of the test verified in the experiment is 0.9844 on ZJU-2 test data and 0.9906 on the ChestX-ray14, respectively. In addition, a large number of atmospheric pleura samples are visualized and analyzed based on the experimental results and in-depth learning characteristics of the algorithm. The analysis results verify the validity of feature extraction for the network. Combined with the results of these two aspects, the proposed X-ray image processing algorithm can effectively improve the classification accuracy of pneumothorax photographs.

Structural and Optical Properties of ZnSe Nanoparticles.

We successfully synthesized ZnSe nanoparticles (NPs) by using a hydrothermal method. Careful analyses of X-ray diffraction pattern and high-resolution transmission electron microscopy images showed that the synthesized ZnSe NPs with the size of ˜100 nm and sphere-like morphology crystallized in the zincblende/cubic structure (the F-43m space group). This was also confirmed based upon characteristic vibration modes recorded by using Raman scattering spectroscopy. The study on room-temperature absorption and photoluminescence (PL) spectra proved ZnSe NPs having high crystal quality with the band gap energy Eg≈2.63 eV at 300 K and excitonic emission peaked at ˜2.64 eV (469 nm). Particularly, as studying temperature-dependent PL spectra, we found the shift of the emission peak towards lower energies while the PL intensity decreased when temperature increased from 15 to 300 K. The PL spectral parameters were analyzed by using the Arrhenius and Varshni laws.

Multiscale Synchrotron-Based Imaging Analysis for the Transfer of PEGylated Gold Nanoparticles In Vivo.

High spatial resolution imaging analysis is urgently needed to explore the biodistribution, transfer and clearance profiles, and biological impact of nanoparticles in the body, which will be helpful to clarify the efficacy of nanomedicine in clinical applications. Herein, by combination with multiscale synchrotron-based imaging techniques, including X-ray fluorescence (XRF) spectrometry, Fourier transform infrared (FTIR) spectroscopy, and micro X-ray phase contrast computed tomography (micro-XPCT), we visually displayed the transfer patterns and site-specific distribution of PEGylated gold nanoparticles (PEG-GNPs) in the suborgans of the liver, spleen, and kidney after an intravenous injection in mice. A combination of XRF and FTIR imaging analysis showed that the PEG bands presented similar distribution patterns with Au in the intraorgans, suggesting the stability of PEGylation on GNPs. We show that the PEG-GNPs presented heterogeneous distribution in the hepatic lobules with a large amount around the portal vein zone and then a gradient decrease in the sinusoidal region and the CV zone; in the spleen, it gradually accumulated in the splenic red pulp over time; and in the kidney, it quickly transported via the bloodstream to the renal pyramids and renal pelvis, and parts of PEG-GNPs finally accumulated in the renal medulla and renal cortex. Multidimensional micro-XPCT images further show that the PEG-GNP transfer in the liver induced hepatic blood vessel dilatation while they transferred in the liver, providing evidence of GNP transport across the blood vessel endothelial barrier.

Shrinking Tonlé Sap and the recent intensification of sand mining in the Cambodian Mekong River.

This paper investigates the impacts of extensive riverbed mining in the Lower Mekong on the water level, extent and volume of the Tonlé Sap Lake, the largest freshwater lake in Southeast Asia. Our results indicate that the lake's volume has decreased from 1980 to 2018 (p-value=0.016), with water levels at Phnom Penh Port and Phnom Penh Bassac showing decreasing trends since 1980 (p-values <0.0001). However, discharge at Phnom Penh Bassac (1960-2002) presented an insignificant trend (p-value=0.147), indicating that riverbed incision due to extensive sand mining in Phnom Penh has affected the Mekong's water levels more than basin-scale climatic factors. Similarly, the modulation of a limited portion of water by upstream dams is unlikely to have caused dramatic inundation variation along the Lower Mekong River around Tonlé Sap. A hysteretic relationship between water levels at Prek Kdam and Tonlé Sap indicates that Tonlé Sap's water level is largely controlled by Tonlé Sap River and the Mekong, and declining water levels at Prek Kdam due to extensive sand mining in Phnom Penh is directly related to the shrinking of the lake. Although there are three main inflows into Tonlé Sap (from the Mekong, local tributaries and direct precipitation), the Mekong's contribution is the largest; tributary discharge and rainfall did not display any significant trend over the investigated period as well. Additionally, the analysis of high-resolution images revealed a recent intensification of riverbed mining, with Phnom Penh being a mining hotspot in the Lower Mekong. Considering its economic and ecological importance, the shrinking of Tonlé Sap would have grave repercussions for the region. Since sand demand is unlikely to weaken in the foreseeable future, these new insights can potentially help inform regulatory frameworks in ensuring sustainable sand extraction rates.

Colocalization for super-resolution microscopy via optimal transport.

Super-resolution fluorescence microscopy is a widely used technique in cell biology. Stimulated emission depletion (STED) microscopy enables the recording of multiple-color images with subdiffraction resolution. The enhanced resolution leads to new challenges regarding colocalization analysis of macromolecule distributions. We demonstrate that well-established methods for the analysis of colocalization in diffraction-limited datasets and for coordinate-stochastic nanoscopy are not equally well suited for the analysis of high-resolution STED images. We propose optimal transport colocalization, which measures the minimal transporting cost below a given spatial scale to match two protein intensity distributions. Its validity on simulated data as well as on dual-color STED recordings of yeast and mammalian cells is demonstrated. We also extend the optimal transport colocalization methodology to coordinate-stochastic nanoscopy.

Assessment of Environmental Changes of Valley of the Undytkan River in Impact Zone of the Elginsky Coal Complex and the Railway Track “Ulak- Elga” with Use of Ground and Remote Methods

Environmental monitoring studies are of primary importance to assess the characteristics of anthropogenic changes in the environment on the territory of the Elginsky coking coal deposit, which is one of the largest resource potential of the Republic of Sakha (Yakutia). Due to the inaccessibility and territorial remoteness of the field, remote research methods are a valuable tool for environmental monitoring. The article shows the experience of using the satellite image analysis method for assessing anthropogenic impact and spatial detection of changes in the components of the natural environment in conjunction with field study. On the territory of the Elginsky deposit there is a complex of production, infrastructure and linear structures: coal mine, processing plant, hydraulic structures, shift camp, power transmission lines, roads and railways, as well as a railroad bridge under construction. Technical structures interact with the components of the natural environment and modify them, forming geotechnical (geotechnical) systems. Two geotechnical systems were considered in the article: (a) ‘Elginsky coal mining complex - natural environment’ and (b) ‘River – Bridge’ on the Undytkan River, formed as a result of interaction of the valley of the Undytkan River and a complex of linear road structures of railway track “Ulak – Elga”. And the analysis of high-resolution satellite images, as well as data from expeditionary ground-based studies, made it possible to establish that the formation and functioning of the transport geotechnical system led to a change in a number of components of the natural environment — mesorelief, hydrological parameters of surface waters, inhibition of vegetation cover, and changes in soils associated with increased water level, as well as with icing processes.

Human microsporidian pathogen Encephalitozoon intestinalis impinges on enterocyte membrane trafficking and signaling.

Microsporidia are a large phylum of obligate intracellular parasites. Approximately a dozen species of microsporidia infect humans, where they are responsible for a variety of diseases and occasionally death, especially in immunocompromised individuals. To better understand the impact of microsporidia on human cells, we infected human colonic Caco2 cells with Encephalitozoon intestinalis, and showed that these enterocyte cultures can be used to recapitulate the life cycle of the parasite, including the spread of infection with infective spores. Using transmission electron microscopy, we describe this lifecycle and demonstrate nuclear, mitochondrial and microvillar alterations by this pathogen. We also analyzed the transcriptome of infected cells to reveal host cell signaling alterations upon infection. These high-resolution imaging and transcriptional profiling analysis shed light on the impact of the microsporidial infection on its primary human target cell type.This article has an associated First Person interview with the first authors of the paper.

Insights into the pathogenesis of cerebral fusiform aneurysms: high-resolution MRI and computational analysis

BackgroundIntracranial fusiform aneurysms are complex and poorly characterized vascular lesions. High-resolution magnetic resonance imaging (HR-MRI) and computational morphological analysis may be used to characterize cerebral fusiform aneurysms.ObjectiveTo use advanced imaging...

Microstructural evolution in self-catalyzed GaAs nanowires during in-situ TEM study

The microstructural evolutions in self-catalyzed GaAs nanowires (NWs) were investigated by using in situ heating transmission electron microscopy (TEM). The morphological changes of the self-catalyst metal gallium (Ga) droplet, the GaAs NWs, and the atomic behavior at the interface between the self-catalyst metal gallium and GaAs NWs were carefully studied by analysis of high-resolution TEM images. The microstructural change of the Ga-droplet/GaAs-NWs started at a low temperature of ∼200 °C. Formation and destruction of atomic layers were observed at the Ga/GaAs interface and slow depletion of the Ga droplet was detected in the temperature range investigated. Above 300 °C, the evolution process dramatically changed with time: The Ga droplet depleted rapidly and fast growth of zinc-blende (ZB) GaAs structures were observed in the droplet. The Ga droplet was completely removed with time and temperature. When the temperature reached ∼600 °C, the decomposition of GaAs was detected. This process began in the wurtzite (WZ) structure and propagated to the ZB structure. The morphological and atomistic behaviors in self-catalyzed GaAs NWs were demonstrated based on thermodynamic considerations, in addition to the effect of the incident electron beam in TEM. Finally, GaAs decomposition was demonstrated in terms of congruent vaporization.

Magnetic nanoparticles: An indicator of health risks related to anthropogenic airborne particulate matter.

Due to their small dimensions, airborne particles are able to penetrate through inhalation into many human organs, from the lungs to the cardiovascular system and the brain, which can threaten our health. This work establishes a novel approach of collecting quantitative data regarding the fraction, the composition and the size distribution of combustion-emitted particulate matter through the magnetic characterization and analysis of samples received by common air pollution monitoring. To this end, SQUID magnetometry measurements were carried out for samples from urban and suburban areas in Thessaloniki, the second largest city of Greece, taking into consideration the seasonal and weekly variation of airborne particles levels as determined by occurring traffic and meteorological conditions. The level of estimated magnetically-responding atmospheric particulate matter was at least 0.5 % wt. of the collected samples, mostly being present in the form of ultrafine particles with nuclei sizes of approximately 14nm and their aggregates. The estimated quantities of magnetic particulate matter show maximum values during autumn months (0.8 % wt.) when increased commuting takes place, appearing higher in the city center by up to 50% than those in suburban areas. In combination with high-resolution transmission electron imaging and elemental analysis, it was found that Fe3O4 and similar ferrites, some of them attached to heavy metals (Co, Cr), are the dominant magnetic contributors arising from anthropogenic high-temperature processes, e.g. due to traffic emissions. Importantly, nasal cytologic samples collected from residents of both central and suburban areas showed same pattern in what concerns magnetic behavior, thus verifying the critical role of nanosized magnetic particles in the assessment of air pollution threats. Despite the inherent statistical limitations of our study, such findings also indicate the potential transmission of infectious pathogens by means of pollution-derived nanoparticles into the respiratory system of the human body.

PERFORMANCE OF AIR INDUCTION SPRAY NOZZLE MODELS UNDER DIFFERENT OPERATING CONDITIONS

ABSTRACT For the successful application of phytosanitary products, it is essential to understand the spraying process well. The present work aims to evaluate the spectrum and speed of the droplets produced by different spray nozzle models with air induction, working under different operating conditions. The experiment was conducted using an entirely randomized design with five repetitions in a 3 × 3 × 3 factor scheme that incorporates three nozzle models (ADIA, AIXR, and GA), three nominal flows (0.76, 1.14, and 1.51 L min−1), and three operating pressures (200, 300, and 400 kPa). The spectrum and speed of the droplets were determined directly using a real-time droplet analyzer based on high-resolution image analysis. The spray nozzle model interfered with the results. The ADIA promoted Dv0.5 (VMD) higher than AIXR and GA, reaching differences of up to 90%. The increase in pressure promoted a reduction in the droplet size; however, there was no well-defined behavior for the relationship between the flow rate and droplet size. The ADIA and AIXR gave rise to greater uniformity of the droplets in most of the evaluated conditions. The increase in pressure promoted an increase in the speed of the droplets. However, the effect of the nozzle model on this parameter was dependent on the flow.

Statistical analysis of the crack sensitivity of fiber networks

Fracturing two-dimensional random fiber networks of different densities (porosities) were statistically analyzed using both high-resolution finite element models and image analysis algorithms. Under small strains, the finite element fracture models revealed that networks with high relative densities were able to localize evolving fractures to small cracks while surprisingly larger cracks were required to localize fractures in networks of lower density. Further, it is indicated that the pore size distribution in fiber networks is rather diverse and can be captured using two mixed Gamma distributions; one part describing the background size distribution containing the vast majority of pores, and a second part describing the size distribution of larger pores and open regions. The second part covers less than 5% of the total network area but seems to be of paramount importance for the network’s global fracture behavior. It seems as a fiber network’s crack sensitivity is related to the average pore size in the second part of the mixed Gamma distribution. The analysis is remarkably consistent with reported experiments.

Assessing the performance of the multi-morphological profiles in urban land cover mapping using pixel based classifiers and very high resolution satellite imagery

Improved spatial and spectral resolution from recent sensor advancements provides opportunities for detailed and enhanced accuracies in the classification of heterogeneous urban landscapes. However, to date, such classifications have remained a challenge for most pixel based techniques. Whereas object based techniques have proved effective in classifying heterogeneous urban landscapes, by providing an effective framework for analysis of high spatial resolution images, challenges such as under and over-segmentation and non-robust statistical estimation impede their optimum performance in the often complex urban landscapes. Therefore, it is imperative that an effective classification approach is identified for effective utilisation of both spatio-spectral characteristics of image objects. Morphological techniques, especially multi-morphological profiles (MMP), provide an effective framework for the analysis of both spectral and spatial information from very high-resolution satellite imagery by performing image analysis based on features such as geometric, texture and contrast. In this study, using Support Vector Machine (SVM) and Maximum Likelihood (ML) classification algorithms, we compare the classification accuracies based on MMP as feature vector against those without MMP as a feature vector. Results from this study indicate that the use of MMP as a feature vector produced significantly higher classification accuracies of 84.8% and 82.2%, compared to 75.77% and 77.6% without MMP as a feature vector for SVM and ML, respectively. The study concludes that MMP can be used as a feature vector to increase the classification accuracy of a heterogeneous urban land use land cover.

Early Miocene (Burdigalian) marine rocky shores in the French Jura Massif: a palaeoecological and palaeoenvironmental analysis

Fossil bioerosion traces at a new site of Les Bez (Jura Department) and those already known from Verrieres-de-Joux (Doubs Department) in the central French Jura record an ancient Miocene cliffed shoreline cut into Lower Cretaceous limestones. Both localities are at about 900 m above the present sea level. Caulostrepsis, Gastrochaenolites and Circolites are the ichnogenera identified at Les Bez, whereas only Gastrochaenolites is present at Verrieres-de-Joux. This ichnoassociation identifies the Entobia ichnofacies, which corresponds to the upper infralittoral marine environment, biologically associated with the biocenosis of photophilic algae. By means of digital analysis of high-resolution field images, the percentage of the surface affected by the erosive activity of polychaete worms, bivalves and echinoids has been calculated. This information permits a better evaluation of their biological activity, thus complementing the data on the number of specimens per surface area. The cliff preserved at Les Bez was more affected, showing Gastrochaenolites with diameters smaller than those at Verrieres. The Circolites–Caulostrepsis association is well developed at Les Bez, where polychaete borings are located within echinoid bowl-shaped pits with particular patterns, suggesting an ecological relationship between involved organisms. Moreover, the distribution of the borings along this outcrop is not uniform and digital analysis at three sections (A, B and C) suggests a lower and an upper zone developed on the outcrop under slightly different environmental conditions within the upper infralittoral. The exceptional preservation of the Les Bez fossil cliff-site demands protection in order to ensure its future existence and accessibility.

The Kasei Valles, Mars: a unified record of episodic channel flows and ancient ocean levels

There is widespread evidence across Mars of past flows in major channel systems as well as more than one palaeo ocean level. However, evidence for the timing of channel flows and ocean levels is based on geographically diverse sources with a limited number of dates, making reconstructions of palaeo flows and ocean levels patchy. Here, based on high-resolution topography, image analysis and crater statistics, we have dated 35 different surfaces in Kasei Valles, that are predominantly found within erosional units enabling us to reconstruct a fascinating timeline of episodic flooding events (ranging from 3.7 to 3.6 Ga to ca. 2.0 Ga) interacting with changing ocean/base levels. The temporal correlation of the different surfaces indicates five periods of channel flows driving the evolution of Kasei Valles, in conjunction with the development of (at least) two ocean levels. Furthermore, our results imply that such ocean rose in elevation (ca. 1000 m) between ca. 3.6 Ga and 3.2 Ga and soon afterwards disappeared, thereby indicating a complex ancient Martian hydrosphere capable of supporting a vast ocean, with an active hydrological cycle stretching into the Amazonian.

Multiscale Analysis of Extracellular Matrix Remodeling in the Failing Heart.

Cardiac ECM (extracellular matrix) comprises a dynamic molecular network providing structural support to heart tissue function. Understanding the impact of ECM remodeling on cardiac cells during heart failure (HF) is essential to prevent adverse ventricular remodeling and restore organ functionality in affected patients. We aimed to (1) identify consistent modifications to cardiac ECM structure and mechanics that contribute to HF and (2) determine the underlying molecular mechanisms. We first performed decellularization of human and murine ECM (decellularized ECM) and then analyzed the pathological changes occurring in decellularized ECM during HF by atomic force microscopy, 2-photon microscopy, high-resolution 3-dimensional image analysis, and computational fluid dynamics simulation. We then performed molecular and functional assays in patient-derived cardiac fibroblasts based on YAP (yes-associated protein)-transcriptional enhanced associate domain (TEAD) mechanosensing activity and collagen contraction assays. The analysis of HF decellularized ECM resulting from ischemic or dilated cardiomyopathy, as well as from mouse infarcted tissue, identified a common pattern of modifications in their 3-dimensional topography. As compared with healthy heart, HF ECM exhibited aligned, flat, and compact fiber bundles, with reduced elasticity and organizational complexity. At the molecular level, RNA sequencing of HF cardiac fibroblasts highlighted the overrepresentation of dysregulated genes involved in ECM organization, or being connected to TGFβ1 (transforming growth factor β1), interleukin-1, TNF-α, and BDNF signaling pathways. Functional tests performed on HF cardiac fibroblasts pointed at mechanosensor YAP as a key player in ECM remodeling in the diseased heart via transcriptional activation of focal adhesion assembly. Finally, in vitro experiments clarified pathological cardiac ECM prevents cell homing, thus providing further hints to identify a possible window of action for cell therapy in cardiac diseases. Our multiparametric approach has highlighted repercussions of ECM remodeling on cell homing, cardiac fibroblast activation, and focal adhesion protein expression via hyperactivated YAP signaling during HF.

Analysis of a Wide Range of Commercial Exterior Wood Coatings

This study was focused on measuring the properties of twenty-three commercially available coatings formulated for exterior wood applications. The coatings were characterized by measuring their surface tension, solid content, viscosity, pH, and glass transition temperatures (Tg). Additionally, the wetting properties of coating droplets on wood substrates were measured. The contact angle of solvent-based and water-based coatings were characterized on untreated southern yellow pine wood samples using high-resolution image analysis and the Young–Laplace solution. An innovative image processing technique for determining the average diameter of coating droplets on wood was developed, and an iterative method to calculate the average contact angle using the Young–Laplace solution was applied. The water-resistance of the coated wood samples was evaluated during one week of water immersion tests. In general, solvent-based coatings had significantly lower contact angles and water uptake than water-based coatings. Water-based paint samples had the largest average contact angle (81°), and solvent-based transparent penetrating stains had the smallest contact angle (13.9°). A strong correlation was observed between the coating water uptake and their surface tension and solid content.

High-resolution characterization of male ornamentation and re-evaluation of sex linkage in guppies.

Coloration plays a key role in the ecology of many species, influencing how an organism interacts with its environment, other species and conspecifics. Guppies are sexually dimorphic, with males displaying sexually selected coloration resulting from female preference. Previous work has suggested that much of guppy colour pattern variation is Y-linked. However, it remains unclear how many individual colour patterns are Y-linked in natural populations as much of the previous work has focused on phenotypes either not found in the wild, or aggregate measures such as total colour area. Moreover, ornaments have traditionally been identified and delineated by hand, and computational methods now make it possible to extract pixels and identify ornaments with automated methods, reducing the potential for human bias. Here we developed a pipeline for semi-automated ornament identification and high-resolution image analysis of male guppy colour patterns and applied it to a multigenerational pedigree. Our results show that loci controlling the presence or the absence of individual male ornaments in our population are not predominantly Y-linked. However, we find that ornaments of similar colour are not independent of each other, and modifier loci that affect whole animal coloration appear to be at least partially Y-linked. Considering these results, Y-linkage of individual ornaments may not be important in driving colour changes in natural populations of guppies, or in expansions of the non-recombining Y region, while Y-linked modifier loci that affect aggregate traits may well play an important role.

In situhigh-temperature X-ray diffraction study of Sc-doped titanium oxide nanocrystallites

Titanium dioxide is an inexpensive wide-gap highly ionic semiconductor with striking photocatalytic capabilities in several heterogeneous photoredox reactions. A small crystal size is desirable to maximize the surface area, since photocatalytic reactions occur at the surface of a photocatalyst. Presented here are the synthesis and microstructural characterization of 4 at.% Sc-doped TiO2(4SDT) prepared by water-based co-precipitation. The crystal structure of 4SDT was examined viain situhigh-temperature powder X-ray diffraction experiments from 25 to 1200°C. Rietveld analysis revealed single-phase anatase up to 875°C, while at 900°C the anatase-to-rutile phase transformation occurred and at higher temperatures additional reflections of Sc-rich phases (Sc2TiO5from 975°C and Ti3Sc4O12or Sc2O3at 1200°C) were observed. Debye function analysis (DFA) was applied to model the total scattering pattern directly in reciprocal space, allowing the reconstruction of Ti vacancies. Both Rietveld and DFA methods were applied to estimate the nanocrystallite size and shape with consistent growth in crystallite size with temperature: an ellipsoid shape with equatorial ∼4.7 nm / axial (001) ∼6.9 nm at 25°C to equatorial ∼27.9 nm / axial (001) ∼39.6 nm at 900°C refined by Rietveld analysis,versusa cylinder shape withDa,b= 4.3 nm and size dispersion σab= 1.5 nm,Lc= 4.9 nm and σc= 2.3 nm at 25°C toDa,b= 21.4 nm, σab= 8.3 nm,Lc= 23.9 and σc= 10.9 nm at 900°C estimated by DFA. The microstructural changes obtained by Rietveld and DFA methods were supported by high-resolution transmission electron microscopy image analysis, as well as by the less direct nitrogen sorption techniques that provide information on the size of non-agglomerated and dense particles. The Ti site-occupancy factor showed a linear increase from 0.6–0.8 at 25°C to unity at 900°C for anatase, and from ∼0.7 at 900°C to unity at 1200°C for rutile, via Rietveld analysis and DFA.