Spotty Patterns Research Articles

Relationship between hyperintensity on MRI-T1WI and hemorrhagic transformation after cerebral infarction and its influencing factors

This study aims to investigate the correlation between hyperintensity on Magnetic Resonance Imaging-T1 weighted imaging (MRI-T1WI) and post-infarction hemorrhagic transformation (HT) after cerebral infarction (CI) and analyze the influencing factors. This retrospective study comprised 115 patients diagnosed with cerebral infarction at our hospital. Their clinical data were collected, and they were then divided into a hyperintensity and a non-hyperintensity group based on their T1WI image characteristics. Comparative analysis was performed and the diagnostic value of T1WI hyperintensity for HT and influencing factors were assessed. Lesions in the 115 cerebral infarction patients were distributed as follows: 52 in the cerebral cortex, 37 in the basal ganglia, 14 in the cerebellum, 7 in the thalamus, and 5 in the subcortex. Hyperintensity on T1WI was observed in 4 cases before treatment, which increased to 27 cases after treatment, including 16 affecting the cerebral cortex. These hyperintense signals manifested as spotty, patchy or linear patterns along the gyri. In the basal ganglia, 10 cases exhibited spotty or patchy signals, surrounded by an annular hypointense shadow. Additionally, 3 cases involved the cerebellum, 1 the thalamus, and 1 the subcortex, all with spotty or patchy hyperintensities. HT occurred in 17 out of 115 patients (14.78%) one month after treatment. The diagnostic performance of T1WI hyperintensity for HT showed sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of 94.12%, 84.69%, 86.09%, 51.61% and 98.81%, respectively, with a Kappa value of 0.588. Multivariate logistic regression analysis revealed that age, atherosclerosis, and infarct size were significant risk factors for T1WI hyperintensity in cerebral infarction (p < 0.05). Hyperintensity on T1WI in cerebral infarction primarily correlates with HT and could be a valuable diagnostic marker for HT, with age, atherosclerosis and infarct size identified as potential influencing factors.

Versican contributes to ligament formation of knee joints.

Versican is a large proteoglycan in the extracellular matrix. During embryonic stages, it plays a crucial role in the development of cartilage, heart, and dermis. Previously, we reported that Prx1-Vcan conditional knockout mice, lacking Vcan expression in mesenchymal condensation areas of the limb bud, show the impaired joint formation and delayed cartilage development. Here, we investigated their phenotype in adults and found that they develop swelling of the knee joint. Histologically, their newborn joint exhibited impaired formation of both anterior and posterior cruciate ligaments. Immunostaining revealed a decrease in scleraxis-positive cells in both articular cartilage and ligament of Prx1-Vcan knee joint, spotty patterns of type I collagen, and the presence of type II collagen concomitant with the absence of versican expression. These results suggest that versican expression during the perinatal period is required for cruciate ligaments’ formation and that its depletion affects joint function in later ages.

CO Sensing Properties of Chemiresistive In₂O₃/SnO₂ Composite Nanoparticle Sensors.

In₂O₃/SnO₂ composite nanoparticles (NPs) were synthesized by a hydrothermal method. Fringes and spotty patterns were observed in high-resolution TEM images and corresponding selected area electron diffraction pattern, respectively, suggesting the nanoparticles were single crystals. X-ray diffraction results revealed that the In₂O₃/SnO₂ composite NP sensor consisted of three phases: In₂O₃, SnO₂ and In₂Sn₂O7-x (indium tin oxide: ITO). Energy-dispersive X-ray spectrum of the 9:1 In₂O₃/SnO₂ composite NPs showed the atomic ratio of In₂O₃ to SnO₂ was close to 9:1. The response of the chemiresistive sensor to CO was 9.2, which is within the highest 15% among the response values reported for the past 10 years. The ITO NP-based gas sensor is selective toward CO against other reducing gases such as toluene, acetone and benzene. The enhanced response of the 9:1 In₂O₃/SnO₂ composite NP sensor to CO compared to the pure In₂O₃ NP sensor can be explained mainly by the stronger resistance modulation at the In₂O₃/SnO₂ junctions.

Predominance and homogeneity patterns of physiological FDG accumulation in thoracic and lumbar vertebrae: suspected mechanism of “bone pseudometastasis” on FDG-PET in Japanese patients with esophageal cancer

False-positive bone lesions (bone pseudometastases) have been often reported in patients with esophageal cancer (EsoC). This study aimed to evaluate the vertebral 2-deoxy-2-[18F] fluoro-D-glucose (FDG) accumulation pattern in patients with newly diagnosed esophageal cancers and other malignancies (OtherT) to elucidate the possible mechanism that causes bone pseudometastasis. FDG positron emission tomography/computed tomography performed for 90 patients with EsoC, and 112 patients with OtherT was retrospectively evaluated. The uptake pattern in the thoracic (Th) and lumbar (L) vertebrae was visually assessed regarding predominance (TL, Th ≒ L; Td, Th > L; Ld, L > Th), main intensity compared with the uptake in the blood pool (BP) (Grade 1 < BP, Grade 2 ≒ BP, or Grade 3 > BP), and homogeneity (homogeneous, heterogeneous, marginal, or spotty). The patterns between EsoC and OtherT and between Th and L were compared. TL, Td, and Ld patterns were observed in 51.1%, 48.9%, and 0% in EsoC and 79.7%, 20.3%, and 0% in OtherT. Though Grade 2 was most frequently observed in both groups, the ratio of Grade 3 in Th and Grade 1 in L was significantly higher in EsoC than in OtherT. Heterogeneous and spotty patterns were more frequently observed in L and in EsoC, and these were strongly associated with Td pattern. Td pattern was frequently seen, especially in EsoC, and was strongly associated with a heterogeneous or marginal pattern in the L. Heterogeneous marrow distribution with declined lumbar uptake is suspected as the mechanism of bone pseudometastasis.

Investigation of structural and magnetic properties of multiferroic La1-xYxFeO3 Perovskites, prepared by citrate auto-combustion technique

Abstract In this work, the structural and magnetic properties of multiferroic La 1 - x Y x FeO 3 perovskites, (x = 0.00, 0.05, 0.10, 0.15, 0.20, 0.25 and 0.30) synthesized through Sol-gel auto-combustion technique were investigated.The room temperature synchrotron X-ray diffraction (XRD) analysis revealed that the all the synthesized samples consisted of the polycrystalline orthorhombic structure perovskites (space group pnma), and tolerance factor confirmed the phase stability of the prepared perovskite system.The Williamson-Hall plots based on synchrotron XRD data were employed to estimate the average particle diameter and vary from 18.8 nm to 37.5 nm.For a deeper insight into the crystal structure, high-resolution transmission microscopy imaging (HRTEM) was performed.The estimated values of crystallite size from HRTEM and synchrotron XRD data were coincident.Many of crystallographic parameters and electron density measurements were calculated by Rietveld refinement of synchrotron XRD data. La 1 - x Y x FeO 3 perovskite crystals are canted antiferromagnets with a weak ferromagnetism at room temperature.Selected Area Electron Diffraction (SAED) patterns of the investigated samples exhibited spotty ring patterns, confirming the polycrystalline character.The magnetic properties were gotten through analyzing the magnetization versus temperature M(T) and M(H) hysteresis loop which characterized by a vibrating sample magnetometer (VSM). The orthoferrite La 1 - x Y x FeO 3 crystals are a promising candidate for optical device applications in broad temperature range and high power system.

Investigation of Structural and Magnetic Properties of Multiferroic La1-Xyxfeo3perovskites, Prepared by Citrate Auto-Combustion Technique

In this work, we studied the structural and magnetic properties of multiferroic La1-xYxFeO3 perovskites, (x= 0.0, 0.05, 0.1, 0.15, 0.25 and 0.3) which synthesized through Sol-gel auto-combustion technique using a citric acid as a fuel. The room temperature synchrotron X-ray diffraction (XRD) analysis revealed that the all the synthesized samples consisted of the polycrystalline orthorhombic structure perovskites(space group pnma), and tolerance factor confirmed the phase stability of the prepared perovskite system.The Williamson-Hall plot based on synchrotron XRD data were employed to estimate the average particle diameter and varies from 18 nmto 27.8 nm.For a deeper insight of the crystal structure, high resolution transmission microscopy imaging (HRTEM) was performed. The estimated values of crystallite size from HRTEM and synchrotron XRD data were coincident. Many of crystallographic parameters and electron density measurements were calculated by Rietveld refinement of synchrotron XRD data. La1-xYxFeO3 perovskite crystalsarecanted antiferromagnets with a weak ferromagnetism in room temperature.The magnetic properties were gotten through analyzing the magnetization versus temperature M(T) and M(H) hysteresis loop which characterized by a vibrating sample magnetometer (VSM). The molecular structure showed the decrease of the tilting of the octahedra &lt;FeO6&gt; with increasing Y content trying to strengthen the ferromagnetic character. Selected Area Electron Diffraction (SAED) patterns of the investigated samples exhibited spotty ring patterns,confirming the polycrystalline character.The orthoferrite La1-xYxFeO3 crystalsare a promising candidate for optical device applications in broad temperature range and high power system.

Imaging Kayser-Fleischer Ring in Wilson Disease Using In Vivo Confocal Microscopy.

This study analyzes images of Kayser-Fleischer (K-F) rings in patients with Wilson disease (WD) using in vivo confocal microscopy (IVCM) and explores whether IVCM can be a useful clinical tool in facilitating the diagnosis and characterization of K-F rings. One hundred four eyes of 52 patients with WD and K-F rings (K-F group) and 52 normal eyes of 52 age- and gender-matched control subjects (control group) were enrolled in the study. Both K-F and control groups consisted of 29 male patients and 23 female patients. IVCM imaging was performed, and images of the peripheral Descemet membrane were analyzed. All patients in K-F group showed abnormal patterns in the peripheral Descemet membrane from IVCM images. These abnormalities can be generally divided into 3 types: patchy, stripy, and spotty patterns. Each patient may have a combination of these patterns, with patchy pattern being most prevalent (100%), whereas stripy and spotty patterns are present in 30% to 40% of the K-F rings. Notably, these patterns are not correlated with other systematic symptoms of WD. IVCM images can be used as an objective clinical diagnostic tool to facilitate the identification of K-F rings and the diagnosis of WD.

Soil Cover of the Svetloyarsk Irrigation System after 50 Years of Reclamation Practices

The state of irrigated soils of the Svetloyarsk irrigation system (Volgograd oblast) after 50 years or irrigation and ameliorative impacts has been assessed with the use of published and new field data, cadastral materials, and remote sensing materials. In the recent two decades, the area of regular irrigation and the volume of irrigation water have decreased, which has led to the lowering of the groundwater level to the depth of 5 m and more. The pattern of sown areas is characterized by a rise in the portion of winter cereals. Surface planing during the construction of the irrigation system led to a considerable transformation of the soil cover. On convex elements, solonetzic and other topsoil horizons were almost completely cut off. In many areas, they were replaced by a mixture of different horizons, including carbonaceous material. There are now significant areas of soils of different geneses with carbonates from the surface. Former solonchakous and slightly solonchakous soils are now at the stage of deep desalinization: soluble salts in them have been washed to the second meter, where slightly or moderately saline horizons with a predominance of sulfates have been formed. Irrigated areas on satellite images are specified by spotty patterns differing from those of natural solonetzic soil complexes because of the significant transformation of the soil cover during the construction and operation of irrigation system. The anthropogenically transformed soils can be mapped. Soil maps reflecting the modern state of the of soil cover of irrigated areas are given.

Optimal and stable random pattern formations

We develop a graph model to describe the vast range of patterns observed in biological structures. For any given number of spotty patterns, a finite number of structures (optimal graphs) is precisely described. The construction of the optimal graphs is based on the minimization of the diffusion dissipation energy. The notion of geometrical stability of structures is introduced. It is demonstrated that the hexagonal array is stable and the square array is not. This explains the reason why the hexagonal array appears more frequently in practice than the square one.

Superb microvascular imaging technology for ultrasound examinations: Initial experiences for hepatic tumors

PurposeTo explore whether superb microvascular imaging (SMI) technology could be helpful for the evaluation of hepatic tumors. Materials and methodsOur institutional review board approved this study, and informed consent was obtained from all of the patients. Twenty-three patients with 29 hepatic tumors were enrolled in our study. The tumors consisted of hemangiomas (n=15), focal nodular hyperplasias (FNHs) (n=7), and hepatocellular carcinomas (n=7). All lesions were pathologically (n=2) or radiologically (n=27) confirmed. The mean tumor diameter was 1.9cm (range, 0.9cm to 5.0cm). Using SMI technology, all lesions were scanned and categorized into subgroups according to the flow pattern on the SMI. ResultsThe hemangiomas exhibited nodular rim patterns (33%) and spotty dot-like patterns (20%), and both of these findings were very specific for the diagnosis of hemangioma. The FNHs exhibited spoke-wheel patterns (43%) and radiating vessel patterns (29%) that were very specific findings for the diagnosis of FNH. The other tumors did not exhibit any specific patterns on SMI. ConclusionEvaluations of the inner vascularities of hepatic tumors with the SMI technique were feasible, and the SMI features were significantly different between the different types of hepatic tumors. These differences could aid the diagnoses of hepatic tumors with US.

Abstract P1-02-01: Evaluation of second-generation photoacoustic mammography in detecting the breast cancer vasculature and hypoxic status; a preliminary study

Abstract Background: Functional imaging of tumor vasculature and oxygenation status is essential for monitoring the therapeutic response to the manipulation of abnormal vasculature. Moreover, it could be also applicable for the detection and risk assessment of breast lesion with borderline malignancy since hypoxia and angiogenesis is known to be associated with the malignant potential of precursor lesion of solid tumor. Photoacoustic mammography (PAM) is a novel optical imaging technology that can visualize the hemoglobin distribution and its oxygen saturation (SO2) noninvasively. We have previously reported a promising clinical result of a prototype model of PAM (Canon Inc., Tokyo, Japan) in breast cancer patients. However, the improvement of spatial resolution and the identification of signal origin are still big challenges when considering its application for clinical settings. Materials and methods: We developed the second-generation model of PAM (PAM-02). This instrument has achieved the improved spatial resolution (1.3mm) and enhanced detectability by carrying a high-sensitive detector. Moreover, it is equipped with B-mode ultrasound, which enables us to identify the tumor location in PAM images more precisely. The distribution of hemoglobin within breast tissue carrying solid tumor was evaluated by using PAM-02 under the approval of the ethics committee in Kyoto University Hospital, Japan. Contralateral breast without tumor was also evaluated as a control if possible. Calculated SO2 from photoacoustic (PA) signals were illustrated by using color scale. Results: Seventeen breast lesions from 15 patients were analyzed including 4 ductal carcinoma in situ (DCIS), 12 invasive ductal carcinoma (IDC) and one usual ductal hyperplasia. Tumor locations were successfully identified in 14 out of 17 lesions (82.3%) by B-mode ultrasound imaging. The location of 3 lesions undetectable by B-mode ultrasound imaging could be identified by comparing with corresponding MRI images. B-mode ultrasound imaging made it easy to distinguish intra-tumoral PA signals from peri-tumoral PA signals. Intra-tumoral PA signals were detectable in 68.7% of malignant lesions (11 out of 16 lesions). Peri-tumoral PA signals, which were suggested to be from feeding vessels, were detectable in 81.3% of malignant lesion (13 out of 16 lesions). In the case of benign UDH, PA signals were not detected in either intra- or peri-tumoral region. Intra-tumoral SO2 was estimated to be lower than peri-tumoral SO2 in malignant lesion. While peri-tumoral PA signals were often described as continuous vasculature, intra-tumoral PA signals often showed the spotty patterns. In addition, PA signal density was relatively higher in DCIS compared with IDC. These findings was supposed to reflect the decreased hemoglobin perfusion within solid structure of breast cancer. The minimum detectable lesion was DCIS with a diameter of 8mm. Conclusion: Improved spatial resolution and combination with B-mode ultrasound imaging facilitate the region-specific evaluation of PAM imaging. PAM-02 was supposed to be feasible for evaluating the hypoxic status within small breast tumor and its microenvironment. Citation Format: Masahiro Kawashima, Iku Yamaga, Masae Torii, Mariko Tokiwa, Fakhrejahani Elham, Masako Kataoka, Shotaro Kanao, Masahiro Takada, Yasufumi Asao, Tsuyoshi Shiina, Masakazu Toi. Evaluation of second-generation photoacoustic mammography in detecting the breast cancer vasculature and hypoxic status; a preliminary study [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P1-02-01.

Ecological feedbacks. Termite mounds can increase the robustness of dryland ecosystems to climatic change.

Self-organized spatial vegetation patterning is widespread and has been described using models of scale-dependent feedback between plants and water on homogeneous substrates. As rainfall decreases, these models yield a characteristic sequence of patterns with increasingly sparse vegetation, followed by sudden collapse to desert. Thus, the final, spot-like pattern may provide early warning for such catastrophic shifts. In many arid ecosystems, however, termite nests impart substrate heterogeneity by altering soil properties, thereby enhancing plant growth. We show that termite-induced heterogeneity interacts with scale-dependent feedbacks to produce vegetation patterns at different spatial grains. Although the coarse-grained patterning resembles that created by scale-dependent feedback alone, it does not indicate imminent desertification. Rather, mound-field landscapes are more robust to aridity, suggesting that termites may help stabilize ecosystems under global change.

Termites can stabilize tropical grasslands

Ecological Feedbacks Spotty vegetation patterns in tropical savannas and grasslands can be a warning sign of imminent desertification. However, Bonachela et al. find that termites can also produce spotty patterns. Their theoretical study, confirmed by field data from Kenya, shows that patterns produced by termite mounds are not harbingers of desertification. Indeed, the presence of termites buffers these ecosystems against climate change. Science , this issue p. [651][1] [1]: /lookup/doi/10.1126/science.1261487

Propagating Figured Wood in Black Walnut

Figured black walnut lumber is a specialty wood product that commands a high price for manufacturing fine furniture and interior paneling. Two common figured grain patterns occur in walnut; they are known as “fiddle-back” or “curly” grain, depending on the number of horizontal lines visible in the grain of the finished wood. The occurrence of figured walnut in nature is rare and unpredictable. Trees that have consistent figured patterns throughout the log are of exceptional value. Conversely, trees with partial or spotty figured patterns are considered defective and are reduced in value. Conventional breeding of seedlings, or cloning figured trees by grafting, are possible methods to propagate figured wood in walnut. The value of such material, however, will depend on figure being expressed predictably. For breeding to succeed, the trait of interest must be genetic and heritable. For clonal propagation to be effective, the trait must be reproduced true-to-type. In this study, we evaluate the grain pattern of both grafted and seedling walnut from several highly figured wild selections. Logs from grafted trees of three clones propagated in the 1970s in Kansas were evaluated. Only one log from one clone showed some figure in its lumber. Ten-year-old seedlings from the figured walnut clone “Lamb” were grown and cut in Indiana and evaluated for figured grain, and none showed any sign of figured grain developing. Our conclusion is that figured grain in black walnut does not propagate true-to-type through grafting or by growing open-pollinated seed. Although evidence of some genetic control of figure was found, environmental and other factors appear to play a greater role.

Stripes disrupt odour attractiveness to biting horseflies: Battle between ammonia, CO2, and colour pattern for dominance in the sensory systems of host-seeking tabanids

As with mosquitoes, female tabanid flies search for mammalian hosts by visual and olfactory cues, because they require a blood meal before being able to produce and lay eggs. Polarotactic tabanid flies find striped or spotted patterns with intensity and/or polarisation modulation visually less attractive than homogeneous white, brown or black targets. Thus, this reduced optical attractiveness to tabanids can be one of the functions of striped or spotty coat patterns in ungulates. Ungulates emit CO2 via their breath, while ammonia originates from their decaying urine. As host-seeking female tabanids are strongly attracted to CO2 and ammonia, the question arises whether the poor visual attractiveness of stripes and spots to tabanids is or is not overcome by olfactory attractiveness. To answer this question we performed two field experiments in which the attractiveness to tabanid flies of homogeneous white, black and black-and-white striped three-dimensional targets (spheres and cylinders) and horse models provided with CO2 and ammonia was studied. Since tabanids are positively polarotactic, i.e. attracted to strongly and linearly polarised light, we measured the reflection–polarisation patterns of the test surfaces and demonstrated that these patterns were practically the same as those of real horses and zebras. We show here that striped targets are significantly less attractive to host-seeking female tabanids than homogeneous white or black targets, even when they emit tabanid-luring CO2 and ammonia. Although CO2 and ammonia increased the number of attracted tabanids, these chemicals did not overcome the weak visual attractiveness of stripes to host-seeking female tabanids. This result demonstrates the visual protection of striped coat patterns against attacks from blood-sucking dipterans, such as horseflies, known to transmit lethal diseases to ungulates.

Growth and stuctural characterization of InGaN layers with controlled In content prepared by plasma-assisted molecular beam epitaxy

InGaN layers with controlled In composition up to 30at.% are grown on c-plane sapphire substrates by plasma-assisted molecular beam epitaxy. By considering the growth rate differences in GaN and InN caused by different vapor pressure and sticking coefficient, factors of the Ga and In source fluxes for the targeted In composition are determined. By applying the factors, InGaN layers with the almost same In compositions are grown. Before the growth the substrates were nitrided by rf-nitrogen plasma, which resulted in the formation of epitaxial AlN layer. The growth of thin GaN on this AlN surface shows strong streaky reflection high energy electron diffraction pattern with a specular spot, however, InGaN layers on the GaN layer show spotty patterns. Surface morphology of the InGaN layers shows island-like granules and the granule-like morphology is getting clear as the In composition and roughness are increased, too. The InGaN layers with In composition up to 30at.% do not show formation of InN and only InGaN peaks are detected from the X-ray diffraction. Crystal quality of the InGaN layer with In composition of 15at.% is worse than that of 30at.%-In layer as addressed by larger broadening of X-ray rocking curves.

Spottier Targets Are Less Attractive to Tabanid Flies: On the Tabanid-Repellency of Spotty Fur Patterns

During blood-sucking, female members of the family Tabanidae transmit pathogens of serious diseases and annoy their host animals so strongly that they cannot graze, thus the health of the hosts is drastically reduced. Consequently, a tabanid-resistant coat with appropriate brightness, colour and pattern is advantageous for the host. Spotty coats are widespread among mammals, especially in cattle (Bos primigenius). In field experiments we studied the influence of the size and number of spots on the attractiveness of test surfaces to tabanids that are attracted to linearly polarized light. We measured the reflection-polarization characteristics of living cattle, spotty cattle coats and the used test surfaces. We show here that the smaller and the more numerous the spots, the less attractive the target (host) is to tabanids. We demonstrate that the attractiveness of spotty patterns to tabanids is also reduced if the target exhibits spottiness only in the angle of polarization pattern, while being homogeneous grey with a constant high degree of polarization. Tabanid flies respond strongly to linearly polarized light, and we show that bright and dark parts of cattle coats reflect light with different degrees and angles of polarization that in combination with dark spots on a bright coat surface disrupt the attractiveness to tabanids. This could be one of the possible evolutionary benefits that explains why spotty coat patterns are so widespread in mammals, especially in ungulates, many species of which are tabanid hosts.

Plasma-Assisted Molecular Beam Epitaxy of InXGa1-XN Films on C-plane Sapphire Substrates

We report plasma-assisted molecular beam epitaxy of <TEX>$In_XGa_{1-X}N$</TEX> films on c-plane sapphire substrates. Prior to the growth of <TEX>$In_XGa_{1-X}N$</TEX> films, GaN film was grown on the nitride c-plane sapphire substrate by two-dimensional (2D) growth mode. For the growth of GaN, Ga flux of <TEX>$3.7{\times}10^{-8}$</TEX> torr as a beam equivalent pressure (BEP) and a plasma power of 150 W with a nitrogen flow rate of 0.76 sccm were fixed. The growth of 2D GaN growth was confirmed by <TEX>$in-situ$</TEX> reflection high-energy electron diffraction (RHEED) by observing a streaky RHEED pattern with a strong specular spot. InN films showed lower growth rates even with the same growth conditions (same growth temperature, same plasma condition, and same BEP value of III element) than those of GaN films. It was observed that the growth rate of GaN is 1.7 times higher than that of InN, which is probably caused by the higher vapor pressure of In. For the growth of <TEX>$In_xGa_{1-x}N$</TEX> films with different In compositions, total III-element flux (Ga plus In BEPs) was set to <TEX>$3.7{\times}10^{-8}$</TEX> torr, which was the BEP value for the 2D growth of GaN. The In compositions of the <TEX>$In_xGa_{1-x}N$</TEX> films were determined to be 28, 41, 45, and 53% based on the peak position of (0002) reflection in x-ray <TEX>${\theta}-2{\theta}$</TEX> measurements. The growth of <TEX>$In_xGa_{1-x}N$</TEX> films did not show a streaky RHEED pattern but showed spotty patterns with weak streaky lines. This means that the net sticking coefficients of In and Ga, considered based on the growth rates of GaN and InN, are not the only factor governing the growth mode; another factor such as migration velocity should be considered. The sample with an In composition of 41% showed the lowest full width at half maximum value of 0.20 degree from the x-ray (0002) omega rocking curve measurements and the lowest root mean square roughness value of 0.71 nm.

Structural and Spectroscopic Investigation of Ceria Nanofibers Fabricated by Electrospinning Process

We fabricated ceria (<TEX>$CeO_2$</TEX>) nanofibers by applying a mixed solution of polyvinylpyrrolidone (PVP) and various concentrations of cerium nitrate hydrate (<TEX>$Ce(NO_3)_3$</TEX>) ranging from 15.0 to 26.0 wt % by the electrospinning process. Ceria nanofibers were obtained after calcining PVP/<TEX>$Ce(NO_3)_3$</TEX> nanofiber composites at 873 and 1173 K. The SEM images indicated that the diameters of <TEX>$CeO_2$</TEX> nanofibers calcined at 873 and 1173 K were smaller than those of nanofibers obtained at RT. As the amount of cerium increased, the diameter of <TEX>$CeO_2$</TEX> nanofibers increased. XRD analysis revealed that the ceria nanofibers were in cubic form. TEM results revealed that the ceria nanofibers were formed by the interconnection of Ce oxide nanoparticles. The ceria nanofibers obtained at low concentrations of Ce (CeL) showed spotty ring patterns indicated that the ceria nanofibers were polycrystalline structure. And the ceria nanofibers obtained at high concentration of Ce (CeH) showed fcc (001) diffraction pattern. XPS study indicated that the oxidation of Ce shifted from <TEX>$Ce^{3+}$</TEX> to <TEX>$Ce^{4+}$</TEX> as the calcination temperature increased.

Letter by Korosoglou et al Regarding Article, “Association Between High-Sensitivity C-Reactive Protein and Coronary Plaque Subtypes Assessed by 64-Slice Coronary Computed Tomography Angiography in an Asymptomatic Population”

HomeCirculation: Cardiovascular ImagingVol. 4, No. 5Letter by Korosoglou et al Regarding Article, “Association Between High-Sensitivity C-Reactive Protein and Coronary Plaque Subtypes Assessed by 64-Slice Coronary Computed Tomography Angiography in an Asymptomatic Population” Free AccessLetterPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessLetterPDF/EPUBLetter by Korosoglou et al Regarding Article, “Association Between High-Sensitivity C-Reactive Protein and Coronary Plaque Subtypes Assessed by 64-Slice Coronary Computed Tomography Angiography in an Asymptomatic Population” Grigorios Korosoglou, Evangelos Giannitsis and Hugo A. Katus Grigorios KorosoglouGrigorios Korosoglou University of Heidelberg Department of Cardiology Heidelberg, Germany (Korosoglou, Giannitsis, Katus) Search for more papers by this author , Evangelos GiannitsisEvangelos Giannitsis University of Heidelberg Department of Cardiology Heidelberg, Germany (Korosoglou, Giannitsis, Katus) Search for more papers by this author and Hugo A. KatusHugo A. Katus University of Heidelberg Department of Cardiology Heidelberg, Germany (Korosoglou, Giannitsis, Katus) Search for more papers by this author Originally published1 Sep 2011https://doi.org/10.1161/CIRCIMAGING.111.967257Circulation: Cardiovascular Imaging. 2011;4:e26To the Editor:We read with interest the study of Rubin and colleagues,1 who investigated the association between high-sensitivity C-reactive protein (hs-CRP) with the composition and extent of atherosclerotic coronary plaque, based on coronary computed tomography angiography (CCTA). The study cohort consisted of 1004 asymptomatic subjects who underwent 64-slice CCTA as part of a health screening evaluation. Overall, 211 (21%) patients showed coronary artery disease (CAD), yielding mixed, calcified and noncalcified plaques (10%, 9%, and 8%, respectively), which resulted in lumen narrowing of ≥50% in 51 (5%) and in nonobstructive CAD in 160 (16%) cases. Hs-CRP values were arbitrarily separated to low-normal, intermediate, and high. Weak associations were observed between hs-CRP with the presence of any plaque and mixed plaque. No associations were found for either noncalcified or calcified plaque. After adjustment for clinical and laboratory data the association between the presence of plaque (all subtypes) and hs-CRP yielded borderline statistical significance (odds ratio, 1.35; 95% confidence interval, 0.91 to 2.0) for intermediate hs-CRP and of 1.63 (95% confidence interval, 1.09 to 2.44) for high hs-CRP).This report underlines the importance of biochemical markers for patient risk stratification and the potential of noninvasive cardiac imaging to shed light into the underlying pathophysiology of coronary atherosclerosis. However, several issues should be taken into account with this report before interpreting the acquired results. First of all, the patients studied were asymptomatic and self-referred, so that the study results cannot be extrapolated to a routine clinical out patient setting of patients with suspected CAD. Furthermore, the classification of atherosclerotic plaque was performed categorically, and no quantification analysis of the total noncalcified plaque burden was assessed, which is actually possible using contemporary software algorithms.2 Furthermore, the presence of both spotty calcification patterns and vascular remodeling, which have been indicated as markers of plaque vulnerability, were not considered. Particularly, the visual estimation of the calcified plaque area, which guided plaque categorization, may be completely misleading due to blooming effects surrounding coronary calcification, which may result in substantial overestimation of the calcified area. Furthermore, visually guided estimation of calcified plaque content will be strongly dependent on the projection selected for visual analysis. In addition, although native scans seem to have been performed according to the Methods section, results on quantitative calcium scoring and its association with hs-CRP are not reported.From a pathophysiologic point of view, hs-CRP represents a marker of systemic low-grade inflammation. Although this marker was previously reported as a potential predictor of cardiovascular disease, its value for the individual clinical risk profiling was limited in recent studies.3–4 Studying atherosclerotic plaque in patients who underwent clinically indicated CCTA for suspected CAD, we recently demonstrated a close association between plaque composition and high-sensitive troponin T elevation (hs-TnT),2 whereas an independent association with hs-CRP could not be established. In the same line Laufer et al5 recently reported on a strong association between hs-TnT with disease severity and CT plaque burden in a cohort of 646 patients with suspected CAD, whereas again, an association with hs-CRP was not observed. In contrast to hs-CRP, troponins are cardiospecific biomarkers, which are released into the circulation with cardiomyocyte injury. Their role in the diagnostic classification and risk stratification of patients with acute coronary syndromes is clearly established, and recent studies indicate that hs-TnT is also an independent predictor of cardiovascular mortality in patients with stable CAD.6 Together, with our findings and those of Laufer et al, this may implicate that chronic clinically silent plaque microrupture and embolization rather than systemic inflammation may be the right key to comprehend the underlying pathophysiology in stable CAD and possibly predict future plaque rupture and clinical manifestation of acute coronary syndromes.Grigorios Korosoglou, MDEvangelos Giannitsis, MDHugo A. Katus, MD University of Heidelberg Department of Cardiology Heidelberg, GermanyDisclosuresNone.