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Image Capture (image + capture)
Selected AbstractsThe application of structured-light illumination microscopy to hydrocarbon-bearing fluid inclusionsGEOFLUIDS (ELECTRONIC), Issue 2 2008N. J. F. BLAMEY Abstract Structured-light illumination (SLI)-based microscopy offers geologists a new perspective for screening of hydrocarbon-bearing (HCFI) and small aqueous fluid inclusion (AFI) assemblages. This optical-sectioning technique provides rapid, confocal-like imaging, using relatively simple and inexpensive instrumentation. The 3D fluorescent images of HCFI planes and large single HCFIs permit the visualization of the relationships between HCFI assemblages, examination of HCFI morphology, and volume estimates of the fluorescent components within HCFIs. By the use of normal white light illumination, SLI image capture, and varying acquisition time it is also possible to image AFI because of the random movements of vapour bubbles within the inclusions. This allows the near-simultaneous visualization of hydrocarbon and AFI which is of significant importance for the study of sedimentary basins and petroleum reservoirs. SLI is a unique and accessible 3D petrographic tool, with practical advantages over conventional epifluorescence and confocal laser scanning microscopy. [source] Quantifying the three main components of salinity tolerance in cerealsPLANT CELL & ENVIRONMENT, Issue 3 2009KARTHIKA RAJENDRAN ABSTRACT Salinity stress is a major factor inhibiting cereal yield throughout the world. Tolerance to salinity stress can be considered to contain three main components: Na+ exclusion, tolerance to Na+ in the tissues and osmotic tolerance. To date, most experimental work on salinity tolerance in cereals has focused on Na+ exclusion due in part to its ease of measurement. It has become apparent, however, that Na+ exclusion is not the sole mechanism for salinity tolerance in cereals, and research needs to expand to study osmotic tolerance and tissue tolerance. Here, we develop assays for high throughput quantification of Na+ exclusion, Na+ tissue tolerance and osmotic tolerance in 12 Triticum monococcum accessions, mainly using commercially available image capture and analysis equipment. We show that different lines use different combinations of the three tolerance mechanisms to increase their total salinity tolerance, with a positive correlation observed between a plant's total salinity tolerance and the sum of its proficiency in Na+ exclusion, osmotic tolerance and tissue tolerance. The assays developed in this study can be easily adapted for other cereals and used in high throughput, forward genetic experiments to elucidate the molecular basis of these components of salinity tolerance. [source] Status of Mammography after the Digital Mammography Imaging Screening Trial: Digital versus FilmTHE BREAST JOURNAL, Issue 2 2006D. David Dershaw MD Abstract: Well-publicized results of the recent Digital Mammography Imaging Screening Trial (DMIST) have again shown that there is no clear advantage in mammographic screening of the general population with digital versus film mammography. However, several subgroups,women less than 50 years old, pre- or perimenopausal, and denser breasts,did better with digital mammography than with film. Data also suggest that women with the opposite characteristics might do better with film mammography. This article reviews the data of the four studies comparing digital and film mammographic screening. In addition, it describes the technology involved in the two types of mammographic image capture, the advantages and disadvantages of each type of imaging, and the future possibilities opened by digital technique. Because less than one-tenth of mammography units in use in the United States are digital, the availability of this technology to women undergoing screening and to physicians referring patients to screening sites is very limited. The author suggests that the quality of mammography, rather than the technique used to capture the image, is more important in selecting a mammography facility. For those who have a facility that offers both digital and film mammography, consultation on which type of imaging might be better for an individual woman would be appropriate. Because digital mammography from different manufacturers is based on differing technologies and because data comparing the advantages or disadvantages of these differing types of equipment are not available, it is impossible to recommend which type of digital mammography equipment is best for those undergoing mammography with these types of units. [source] Unexpected roles for cryptochrome 2 and phototropin revealed by high-resolution analysis of blue light-mediated hypocotyl growth inhibitionTHE PLANT JOURNAL, Issue 5 2001Kevin M. Folta Summary Blue light (BL) rapidly and strongly inhibits hypocotyl elongation during the photomorphogenic response known as de-etiolation, the transformation of a dark-grown seedling into a pigmented, photoautotrophic organism. In Arabidopsis thaliana, high-resolution studies of hypocotyl growth accomplished by computer-assisted electronic image capture and analysis revealed that inhibition occurs in two genetically independent phases, the first beginning within 30 sec of illumination. The present work demonstrates that phototropin (nph1), the photoreceptor responsible for phototropism, is largely responsible for the initial, rapid inhibition. Signaling from phototropin during the curvature response is dependent upon interaction with NPH3, but the results presented here demonstrate that NPH3 is not necessary for phototropin-dependent growth inhibition. Activation of anion channels, which transiently depolarizes the plasma membrane within seconds of BL, is an early event in the cryptochrome signaling pathway leading to a phase of growth inhibition that replaces the transient phototropin-dependent phase after approximately 30 min of BL. Surprisingly, cry1 and cry2 were found to contribute equally and non-redundantly to anion-channel activation and to growth inhibition between 30 and 120 min of BL. Inspection of the inhibition kinetics displayed by nph1 and nph1cry1 mutants revealed that the cryptochrome phase of inhibition is delayed in seedlings lacking phototropin. This result indicates that BL-activation of phototropin influences cryptochrome signaling leading to growth inhibition. Mutations in the NPQ1 gene, which inhibit BL-induced stomatal opening, do not affect any aspect of the growth inhibition within the first 120 min examined here, and NPQ1 does not affect the activation of anion channels. [source] Digital image analysis of plus disease in retinopathy of prematurityACTA OPHTHALMOLOGICA, Issue 4 2009Tariq Aslam Abstract. An accurate assessment of retinopathy of prematurity (ROP) is essential in ensuring correct and timely treatment of this potentially blinding condition. Current modes of assessment are based upon clinical grading by expert examination of retinal changes. However, this may be subjective, unreliable and difficult and there has been significant interest in alternative means of measurement. These have been made possible through technological advancements in image capture and analysis as well as progress in clinical research, highlighting the specific importance of plus disease in ROP. Progress in these two fields has highlighted the potential for digital image analysis of plus disease to be used as an objective, reliable and valid measurement of ROP. The potential for clinical and scientific advancement through this method is argued and demonstrated in this article. Along with the potential benefits, there are significant challenges such as in image capture, segmentation, measurement of vessel width and tortuosity; these are also addressed. After discussing and explaining the challenges involved, the research articles addressing digital image analysis of ROP are critically reviewed. Benefits and limitations of the currently published techniques for digital ROP assessment are discussed with particular reference to the validity and reliability of outcome measures. Finally, the general limitations of current methods of analysis are discussed and more diverse potential areas of development are discussed. [source] Fred Hollows lecture: Digital screening for eye diseaseCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 3 2000Ij Constable ABSTRACT The purpose of this study was to explore progress, in the adaptation to community screening for blinding eye disease, of digital imaging devices and technology for storage and transmission. Available imaging systems were compared to gold standard clinical photography in terms of sensitivity and specificity for diagnosis of common blinding eye conditions. Since the use of expensive non-portable imaging devices is likely to be limited for widespread community screening purposes, a portable fundus camera (Nidek, Chiyoda-ku, Japan) and a prototype monocular digital indirect ophthalmoscope constructed at the Lions Eye Institute (LEI) were selected for comparative trials for the screening of optic disc cupping, glaucoma and clinical signs of diabetic retinopathy. Fifty-one eyes of 27 consecutive patients being assessed at the LEI clinic for glaucoma were dilated and photographed with a Zeiss retinal camera, and digital images were taken with the portable Nidek NM100 fundus camera (Carl Zeiss, Oberkochen, Germany) or with a prototype digital monocular indirect ophthalmoscope. Vertical cup : disc ratios (VCDR) were measured on the disc photographs by one ophthalmologist while three other clinicians were presented with compressed digital images in random order to estimate VCDR. Field trials were also carried out to demonstrate the practicality of compression, local storage and then transmission by mobile telephone ISDN lines and satellite, of optic discs and fundus images of patients with diabetes in either rural Western Australia or Surabaya, Indonesia. Kappa values of correlations of measurement of agreement between measured and estimated VCDR were 0.87, 0.45 and 0.84, respectively, for the three observers, corresponding to a specificity of 79,97% and a sensitivity of 70,95%. The portable Nidek fundus camera was also assessed for specificity and sensitivity in the diagnosis of diabetic retinopathy in comparison to standard Zeiss fundus camera photographs. Of 49 eyes in 25 consecutive patients attending the LEI clinic for assessment of diabetic retinopathy, three ophthalmologists assessed photographs and images in random order. When used for screening diabetic retinopathy, the digital images of the Nidek camera were graded as adequate quality in only 56% of eyes compared to 93% of the photographs. The kappa value of agreement in analysis of diabetic retinopathy was only 0.30. The prototype digital monocular indirect ophthalmoscope compared favourably with the Nidek camera. At 1:5 compression, images of size 36 kB transmitted from Surabaya to Perth took 29 s on the mobile telephone, while uncompressed images took 170 s. Images compressed 1:5 were transmitted in 60 s using the satellite telephone, while the uncompressed images took 240 s. Satellite transmission was more expensive but the lines were more stable than telephone connections from Indonesia. Digital imaging is becoming a powerful tool for ophthalmology in clinical records, teaching and research, and interoffice diagnostic opinions. It also has enormous potential for community screening for blinding eye diseases, such as glaucoma and diabetic retinopathy. Inexpensive portable imaging devices that are easy to use, and on which local health workers might be trained, must be developed and validated in terms of sensitivity and specificity of performance. The technology of image capture, image compression, transmission, data base storage and analysis is rapidly evolving and becoming less expensive. 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