High-resolution Plates Research Articles

Growth of Neogene Andes linked to changes in plate convergence using high-resolution kinematic models

The Andean cordillera was constructed during compressive tectonic events, whose causes and controls remain unclear. Exploring a possible link to plate convergence has been impeded by the coarse temporal resolution of existing plate kinematic models. Here we show that the Neogene evolution of the Andean margin is primarily related to changes in convergence as observed in new high-resolution plate reconstructions. Building on a compilation of plate finite rotations spanning the last 30 million years and using noise-mitigation techniques, we predict several short-term convergence changes that were unresolved in previous models. These changes are related to main tectono-magmatic events and require forces that are compatible with a range of geodynamic processes. These results allow to revise models of ongoing subduction orogeny at its type locality, emphasizing the role of upper plate deformation in the balance between kinematic energy associated with plate motion and gravitational potential energy stored in orogenic crustal roots.

Determination of the effect of germination on the folate content of the seeds of some legumes using HPTLC-mass spectrometry-multivariate image analysis

Legumes are the main sources of folates which are not synthesized in the human body. The five folate species: 5-methyl tetrahydrofolate, tetrahydrofolate, pteroyl glutamate, 5-formyl tetrahydrofolate and 10-formyl tetrahydrofolate were quantitatively determined in legumes seeds and sprouts by a newly developed and validated high performance thin layer chromatography method. High resolution plate imaging hyphenated to mass spectrometry was exploited for fingerprint analysis of tested samples. Results indicated that germination of all seeds resulted in a 2.5–4 fold increase in the content of total folates as well as the individual vitamers. The total amount of folate reached a maximum on the fifth day in the case of black-eyed peas (861 μg/100 g Fresh Weight), white beans (755 μg/100 g FW) and brown lentils (681 μg/100 g FW). 5-CH3-H4 folate was found to be the most dominating folate species reaching its maximum content in day 5 sprouts of black-eyed peas (490 μg/100 g FW).

Guided ultrasonic wavefield cross-correlation with a curved array for high-resolution plate inspection

Abstract We present in this work an ultrasonic imaging technique based on wavefield cross-correlation that has potential for high-resolution inspecting of plates and plate-like structures. A curved transmit/receive array setup is used for acquiring wide-aperture waveform data beneficial for applying the presented imaging condition. An additional dispersion analysis using waveform data received by a linear array allows one to reveal the excited guided wave modes and possibly determine the shear wave velocity as an input parameter in the 3D wavefield simulation. Using synthetic but realistic data generated by realistic 3D simulations, we demonstrate the invariance of the time reversal process and the capability of the presented imaging approach for ultrasonic testing based on Lamb waves. In addition to the ability to localise and size multiple defects simultaneously, this imaging approach does not require baseline data and involves only minimal waveform data pre-processing.

Global plate boundary evolution and kinematics since the late Paleozoic

Many aspects of deep-time Earth System models, including mantle convection, paleoclimatology, paleobiogeography and the deep Earth carbon cycle, require high-resolution plate motion models that include the evolution of the mosaic of plate boundaries through time. We present the first continuous late Paleozoic to present-day global plate model with evolving plate boundaries, building on and extending two previously published models for the late Paleozoic (410–250Ma) and Mesozoic-Cenozoic (230–0Ma). We ensure continuity during the 250–230Ma transition period between the two models, update the absolute reference frame of the Mesozoic-Cenozoic model and add a new Paleozoic reconstruction for the Baltica-derived Alexander Terrane, now accreted to western North America. This 410–0Ma open access model provides a framework for deep-time whole Earth modelling and acts as a base for future extensions and refinement.We analyse the model in terms of the number of plates, predicted plate size distribution, plate and continental root mean square (RMS) speeds, plate velocities and trench migration through time. Overall model trends share many similarities to those for recent times, which we use as a first order benchmark against which to compare the model and identify targets for future model refinement. Except for during the period ~260–160Ma, the number of plates (16–46) and ratio of “large” plates (≥107.5km2) to smaller plates (~2.7–6.6) are fairly similar to present-day values (46 and 6.6, respectively), with lower values occurring during late Paleozoic assembly and growth of Pangea. This temporal pattern may also reflect difficulties in reconstructing small, now subducted oceanic plates further back in time, as well as whether a supercontinent is assembling or breaking up. During the ~260–160Ma timeframe the model reaches a minima in the number of plates, in contrast to what we would expect during initial Pangea breakup and thus highlighting the need for refinement of the relative plate motion model. Continental and plate RMS speeds show an overall increase backwards through time from ~200 to 365Ma, reaching a peak at 365Ma of >14 and >16cm/yr, respectively, compared to ~3 and ~5cm/yr, respectively, at present-day. The median value of trench motion remains close to, yet above 0cm/yr for most of the model timeframe, with a dominance in positive values reflecting a prevalence of trench retreat over advance. Trench advance speeds are excessive during the 370–160Ma period, reaching more than four times that observed at present-day. Extended periods of trench advance and global continental and plate RMS speeds that far exceed present-day values warrant further investigation. Future work should test whether alternative absolute reference frames or relative motions would mitigate these high speeds, while still being consistent with geologic and geophysical observations, or alternatively focus on identifying potential driving mechanisms to account for such rapid motions.

The Lattice-Based Screen Set: A Square N -Color All-Orders Moiré-Free Screen Set.

Periodic clustered-dot screens are widely used for electrophotographic printers due to their print stability. However, moiré is a ubiquitous problem that arises in color printing due to the beating together of the clustered-dot, periodic halftone patterns that are used to represent different colorants. The traditional solution in the graphic arts and printing industry is to rotate identical square screens to angles that are maximally separated from each other. However, the effectiveness of this approach is limited when printing with more than four colorants, i.e., N -color printing, where N > 4 . Moreover, accurately achieving the angles that have maximum angular separation requires a very high-resolution plate writer, as is used in commercial offset printing. Commercially available high-end digital printers cannot achieve this resolution. In this paper, we propose a systematic way to design color screen sets for periodic, clustered-dot screens that offer more explicit control of the moiré properties of the resulting screens when used in color printing. We develop a principled approach for the moiré-free screen design that is called lattice-based screen design. The basic concept behind our approach is the creation of the screen set on a 2D lattice in the frequency domain, and then picking each fundamental frequency vector of the individual colorant planes in the created spectral lattice according to the desired properties. The lattice-based screen design offers more flexibility in designing N -color screen sets with different halftone geometries, and all of them are guaranteed to be all-orders moiré-free. We demonstrate the efficacy of our proposed method by introducing several new screen designs, and a comparison with published screen designs.

Analysis of phenolics in wine by high performance thin-layer chromatography with gradient elution and high resolution plate imaging

Health benefits of wine, especially with red wine, have been linked to the presence of a wide range of phenolic antioxidants. Thus, the aim of this study was to develop a simple, high performance thin layer chromatographic (HPTLC) method combined with high resolution digital plate images to visually compare multiple wine samples simultaneously on a single chromatographic plate and to quantify levels of gallic acid, caffeic acid, resveratrol and rutin, as representatives of the four different classes of phenolics found in wines. We also wanted to investigate the contribution of the investigated phenolic compounds to the total polyphenolic content (TPC) and total antioxidant capacity (TAC) of the wine samples.The average concentrations of caffeic acid, gallic acid, resveratrol, and rutin in the red wines were 2.15, 30.17, 0.59 and 2.47mg/L respectively with their concentration below limit of quantification in the white wine samples. The highest concentration of resveratrol and rutin is found in the Cabernet and Shiraz wine samples. The amounts of gallic acid are correlated with TPC (r=0.58). Italian wines have the highest correlation between TPC and TAC (r=0.99) although they do not contain detectable amounts of resveratrol, they contain significant amount of rutin. Therefore, antioxidant properties might be associated with the presence of flavanols in these wines.

Evaluation of high-performance thin-layer chromatography for the quantification of phenylpropanoids in commercialEchinaceaproducts

There is a large chemical variability between commercially available Echinacea for both research and consumption impacts on the quality and efficacy of these products. Globally, herbal industries are largely unregulated, leaving manufacturers responsible for quality control. Several recent efforts to improve regulation have created a need for rapid, accurate, and reliable assays suitable for a quality control setting. Thus, the aim of this study was to develop and validate a high-performance thin-layer chromatographic (HPTLC) method for the quantitative analysis of commercial Echinacea products. HPTLC and high-resolution plate imaging were used to separate and quantify the amounts of three phenylpropanoid compounds which were used then as markers in product quality assessment. The developed method was validated according to the current International Conference on Harmonization (ICH) guidelines in terms of accuracy, precision, linearity, specificity, limits of quantification and detection, and robustness a...

Qualitative and quantitative high performance thin layer chromatography analysis of Calendula officinalis using high resolution plate imaging and artificial neural network data modelling

Calendula officinalis, commonly known Marigold, has been traditionally used for its anti-inflammatory effects. The aim of this study was to investigate the capacity of an artificial neural network (ANN) to analyse thin layer chromatography (TLC) chromatograms as fingerprint patterns for quantitative estimation of chlorogenic acid, caffeic acid and rutin in Calendula plant extracts.By applying samples with different weight ratios of marker compounds to the system, a database of chromatograms was constructed. A hundred and one signal intensities in each of the HPTLC chromatograms were correlated to the amounts of applied chlorogenic acid, caffeic acid, and rutin using an ANN.The developed ANN correlation was used to quantify the amounts of 3 marker compounds in calendula plant extracts. The minimum quantifiable level (MQL) of 610, 190 and 940ng and the limit of detection (LD) of 183, 57 and 282ng were established for chlorogenic, caffeic acid and rutin, respectively.A novel method for quality control of herbal products, based on HPTLC separation, high resolution digital plate imaging and ANN data analysis has been developed. The proposed method can be adopted for routine evaluation of the phytochemical variability in calendula extracts.

Development of a High-performance Optical System and Fluorescent Converters for High-resolution Neutron Imaging

Abstract Two novel devices for use in neutron imaging technique are introduced. The first one is a high-performance optical lens for video camera systems. The lens system has a magnification of 1:1 and an F value of 3. The optical resolution is less than 5 μm. The second device is a high-resolution fluorescent plate that converts neutrons into visible light. The fluorescent converter material consists of a mixture of 6 LiF and ZnS(Ag) fine powder, and the thickness of the converter is material is as little as 15 μm. The surface of the plate is coated with a 1 μm-thick gadolinium oxide layer. This layer is optically transparent and acts as an electron emitter for neutron detection. Our preliminary results show that the developed optical lens and fluorescent converter plates are very promising for high-resolution neutron imaging.

地球磁場の形と変動―平均地球磁場と古地磁気永年変化―

Paleomagnetism has been applied to tectonics studies on the basis of the geocentric axial dipole (GAD) field hypothesis. However, the applicability of the GAD hypothesis is still under investigation in the paleomagnetic community. It is directly connected to the precision of the tectonic movements derived from paleomagnetism, so that the the morphology of the geomagnetic field should draw wide attention among Earth scientists. The morphology of the long term geomagnetic features is often represented by the time-averaged field (TAF) and the paleosecular variation (PSV). They are extracted from the paleodirections of lavas erupted during the past 5 My.The recent TAF and PSV models indicate following; (1) the GAD hypothesis is not strictly accurate, (2) the geocentric axial quadupole (g02) field exists in the TAF and it cannot be neglected, and (3) the inclination anomaly calculated from the averaged paleomagnetic data consists also of the apparent effect of the PSV, which additionally cannot be ignored. These components should be paid close attentions to specially in the case of detailed tectonics such as highresolution plate motion. The inclination anomaly due to g02 in the TAF and the effect of the PSV would produce a mistake of the paleolatitude, which becomes totally up to several degrees.

Fabrication of large-area stamps, moulds, and conformable photomasks for soft lithography

Low-cost fabrication is essential to the successful introduction of organic electronics and reel-to-reel manufacturing processes. Here it is proposed that extending flexography into the micrometre-size resolution regime may provide an economical commercialization path for plastic devices. Flexography is a high-speed technique commonly used for printing onto very large-area flexible substrates. Although low resolution and poor registration are characteristics of today's flexographic process, it has many similarities with soft lithographic techniques. This work shows that large (12 in x 12 in), high-resolution printing plates appropriate for use on small tag and label flexographic presses can be prepared using simple and inexpensive flexographic-compatible processes. This paper illustrates the use of these plates for three representative soft lithographic processes: microcontact printing, replica moulding, and phase-shift lithography.

Large Area Microcontact Printing Presses for Plastic Electronics

ABSTRACTLow cost fabrication is key to the successful introduction of organic electronics and roll to roll manufacturing processes. We propose here that extending flexography into the micron size resolution regime may provide an economical commercialization path for plastic devices. Flexography is a high-speed technique commonly used for printing onto very large area flexible substrates.[1] Although low resolution and poor registration are characteristics of today's flexographic process, it has many similarities with soft lithographic techniques. This work shows that large, (12”×12”) high-resolution printing plates appropriate for use on small tag and label flexographic presses can be prepared using simple and inexpensive flexographic compatible processes. We illustrate the use of these plates for three representative soft lithographic processes: microcontact printing, replica molding, and phase shift lithography.

Spectroscopic Portraiture

This paper describes a now widely forgotten tradition in the nineteenth century which - to borrow a simile used or implied by the actors themselves - may be described as 'spectroscopic portraiture'. Quite unlike the later obsession with numerical precision in wavelength measurement, and also in stark contrast to the contemporary vogue of photographic mapping which presumptuously claimed 'mechanical objectivity', that is avoidance of any human intervention in the recorded data, there was among some spectroscopists a much greater preoccupation with qualitative rather than quantitative aspects. The atlases of the solar spectrum by Cornu, Thollon, and Piazzi Smyth were supposed to convey the subjectively perceived Gestalt of the Fraunhofer lines, at the expense of precision. I shall argue that this was a systematic research programme addressed to a welldefined but small audience of specialists in the new subdiscipline of spectroscopy which was distinct from other practices such as spectrum analysis, which was directed mainly at chemists. Apart from this, the new tradition can also be identified by the dense net of cross-references in the publications of the various members, and by their critique of earlier work. This tradition of spectrum portraiture started with Kirchhoff's 1861-2 high-resolution chromolithographic plates of the solar spectrum, which were printed off a half-dozen different stones in order to render most faithfully the various line intensities. Focusing especially on the tension between representational goals and technical possibilities in the rapidly developing printing industry, I then trace the emerging tradition through its apogee to the close of the nineteenth century.

Computed radiography versus screen-film mammography in detection of simulated microcalcifications: A receiver operating characteristic study based on phantom images

The authors compare a 43-micron computed radiographic system with a mammographic screen-film system for detection of simulated microcalcifications in an observer-performance study. The task of detecting microcalcifications was simulated by imaging aluminum wire segments (200-500 microns in length; 100, 125, or 150 microns in diameter) that overlapped with tissue background structures produced by beef brisket. A total of 288 such simulations were generated and examined with both computed radiography and conventional screen-film mammography techniques. Computed radiography was performed with high-resolution plates, a 43-micron image reader, and a 43-micron laser film printer. Computed radiographic images were printed with simple contrast enhancement and compared with screen-film images in a receiver operating characteristic study in which experienced readers detected and scored the simulated microcalcifications. Observer performance was quantitated and compared by computing the area under the receiver operating characteristic curve. Although the resolution of the computed radiography system was better than that of commercial systems, it fell short of that of screen-film systems. For the 100-micron microcalcifications, the difference in the average area under the curve was not statistically significant, but it was significant for the larger simulated microcalcifications: the average area under the curve was 0.58 for computed radiography versus 0.76 for screen-film imaging for the 125-micron microcalcifications and 0.83 versus 1.00, respectively, for the 150-micron microcalcifications. Observer performance in the detection of small simulated microcalcifications (100-150 microns in diameter) is better with screen-film images than with high-resolution computed radiographic images.

Arops : The ASIAGO Red Objective-Prism Survey

AROPS is an objective-prism survey conducted at high galactic latitudes with the 67/92 cm (f=205 cm) Schmidt telescope of the Asiago Astrophysical Observatory (Italy). The basic technical data are: – TP4415 high resolution plates, 20×20 cm, treated in forming gas (H2+N2) and covering 24 deg2 on sky– 4° UBK7 objective prism, for a dispersion of 1490 Åmm−1 at NaI D– blue side cut-off at 4980 Å using a 2mm GG14 filter, for a recorded λ range 5000–7000 Å– untrailed spectra to record V ∼ 16.5 mag stars with 40 min exposures

High-resolution plate reconstruction of the southern Mid-Atlantic Ridge

We use recently acquired magnetic and SeaBeam bathymetric data to examine the spreading rates and plate boundary geometry of the Mid-Atlantic Ridge 30°–36° S. Using a statistically rigorous estimation of rotation poles we develop a precise spreading history of the African—South American plate boundary. The total opening rate for 1–4.23 Myr (Plio-Pleistocene) is nearly constant at 32.3 ± 1 km Myr−1. The spreading rate apparently is faster in the Late Miocene (7.3-5.3 Myr), though this may reflect inaccuracies in the geomagnetic time scale. The rotation poles enable a plate boundary reconstruction with an accuracy of 2–3 km. The reconstructions also show that the plate boundary geometry underwent several changes since the late Miocene including the growth of one ridge segment from 40 to 105 km in length, and the reorientation of another ridge segment which has spread obliquely from 7 to 1 Myr. Pole calculations using both right- and left-stepping fracture zones show an offset of 1–2 km between the deepest, most linear part of a fracture zone trough and the former plate boundary location. The high-resolution plate kinematics suggests that the plate boundary, as a whole, evolves 2-dimensionally as prescribed by rigid plates. On a local scale, asymmetric accretion, asymmetric extension, small lateral ridge jumps (< 3 km), and intra-segment propagation result in minor plate boundary adjustments and deformation to the rigid plates.

Contact Microradiography of Dentine under Wet Conditions to Prevent Lesion Shrinkage

A considerable shrinkage of dentinal lesions is the result of desiccation of dentine sections during contact microradiography. We introduce a simple modification which allows the dentine to be wet during the microradiographic procedure. The volume stability of both sound and demineralized dentine sections microradiographed under wet conditions is compared to sections microradiographed while being exposed to the air. Under wet conditions no shrinkage could be detected of both sound and demineralized sections. Within 15 min exposure to the air, demineralized sections showed their lesion depth to be significantly reduced by 21%, resulting in an underestimation of the mineral loss of 44%. No shrinkage was observed in the air-dried sound dentine. Especially when high-resolution plates are used, which require an extended exposure time, microradiography of dentine sections under wet conditions is recommended. In longitudinal de- and remineralization studies, the use of water instead of impregnation with low-volatility liquids is to be preferred because of the possible effects of these liquids on the mineralization processes.

Laser patterning system for integrated optics and storage applications

A computer-controlled laser writing system for optical integrated circuits and data storage is described. The system is characterized by holographic (649F) and high-resolution plates. A minimum linewidth of 2.5 μm is obtained by controlling the system parameters. We show that this system can also be used for data storage applications

Direct digitization of optical images using a photostimulable phosphor system.

The authors describe a method for directly digitizing optical images with a photostimulable phosphor (PSP) system. A PSP plate is initially charged with an exposure to a uniform x-ray field, and is then exposed to an optical image which discharges the plate in relation to the amount of incident light. Two applications were investigated: a contact-print technique for digitizing film radiographs, and a projection technique for digitizing transparent objects such as histology slides. Spatial uniformity was found to be adequate, and linearity of optical density response was excellent from 0.0-2.9 o.d. after look-up table correction. Spatial frequency response was degraded with the optical technique relative to the x-ray imaging properties of the plates, but was restorable by Fourier filtering. Image noise following spatial enhancement was satisfactory at intermediate to high optical densities using a high-resolution PSP plate, but was somewhat degraded at low densities.

The small-scale clustering properties of dwarf galaxies

Two results on the small-scale clustering properties of dwarf galaxies are reported, which were identified in the vicinity of early-type Shapley-Ames galaxies on high-resolution photographic plates. The first result indicates that dwarf galaxies display the same trend of stronger clustering toward earlier morphological type on small scales as their giant counterparts on larger scales. It is suggested that early-type dwarfs can be used as dynamical probes of dark halos around early-type giant galaxies and as tracers of the dynamical evolution of such halos in dense environments. The second result pertains to the trend of increasing early-type dwarf frequency per early-type giant with environment richness previously established for rich groups. It is found that a minimum value of isolated early-type galaxies is approximately 0.25, as compared to a maximum of approximately 8 in rich environments like the Virgo Cluster.